Lynch syndrome associated with two MLH1 promoter variants and allelic imbalance of MLH1 expression.

Science.gov (United States)

Hesson, Luke B; Packham, Deborah; Kwok, Chau-To; Nunez, Andrea C; Ng, Benedict; Schmidt, Christa; Fields, Michael; Wong, Jason W H; Sloane, Mathew A; Ward, Robyn L

2015-06-01

Lynch syndrome is a hereditary cancer syndrome caused by a constitutional mutation in one of the mismatch repair genes. The implementation of predictive testing and targeted preventative surveillance is hindered by the frequent finding of sequence variants of uncertain significance in these genes. We aimed to determine the pathogenicity of previously reported variants (c.-28A>G and c.-7C>T) within the MLH1 5'untranslated region (UTR) in two individuals from unrelated suspected Lynch syndrome families. We investigated whether these variants were associated with other pathogenic alterations using targeted high-throughput sequencing of the MLH1 locus. We also determined their relationship to gene expression and epigenetic alterations at the promoter. Sequencing revealed that the c.-28A>G and c.-7C>T variants were the only potentially pathogenic alterations within the MLH1 gene. In both individuals, the levels of transcription from the variant allele were reduced to 50% compared with the wild-type allele. Partial loss of expression occurred in the absence of constitutional epigenetic alterations within the MLH1 promoter. We propose that these variants may be pathogenic due to constitutional partial loss of MLH1 expression, and that this may be associated with intermediate penetrance of a Lynch syndrome phenotype. Our findings provide further evidence of the potential importance of noncoding variants in the MLH1 5'UTR in the pathogenesis of Lynch syndrome. © 2015 The Authors. **Human Mutation published by Wiley Periodicals, Inc.

Association of low-activity MAOA allelic variants with violent crime in incarcerated offenders.

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Stetler, Dean A; Davis, Chad; Leavitt, Kathryn; Schriger, Ilana; Benson, Katie; Bhakta, Samir; Wang, Lam Chee; Oben, Cynthia; Watters, Matthew; Haghnegahdar, Tara; Bortolato, Marco

2014-11-01

The main enzyme for serotonin degradation, monoamine oxidase (MAO) A, has recently emerged as a key biological factor in the predisposition to impulsive aggression. Male carriers of low-activity variants of the main functional polymorphism of the MAOA gene (MAOA-uVNTR) have been shown to exhibit a greater proclivity to engage in violent acts. Thus, we hypothesized that low-activity MAOA-uVNTR alleles may be associated with a higher risk for criminal violence among male offenders. To test this possibility, we analyzed the MAOA-uVNTR variants of violent (n = 49) and non-violent (n = 40) male Caucasian and African-American convicts in a correctional facility. All participants were also tested with the Childhood Trauma Questionnaire (CTQ), Barratt Impulsivity Scale (BIS-11) and Buss-Perry Aggression Questionnaire (BPAQ) to assess their levels of childhood trauma exposure, impulsivity and aggression, respectively. Our results revealed a robust (P crime. This association was replicated in the group of Caucasian violent offenders (P crime charges were not associated with CTQ, BIS-11 and BPAQ scores, carriers of low-activity alleles exhibited a mild, yet significant (P genetic determinant for criminal violence. Further studies are required to confirm these results in larger samples of inmates and evaluate potential interactions between MAOA alleles and environmental vulnerability factors. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Val66Met brain-derived neurotrophic factor gene variant interacts with early pain exposure to predict cortisol dysregulation in 7-year-old children born very preterm: Implications for cognition.

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Chau, C M Y; Cepeda, I L; Devlin, A M; Weinberg, J; Grunau, R E

2017-02-07

Early stress in the form of repetitive neonatal pain, in infants born very preterm, is associated with long-term dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and with poorer cognitive performance. Brain-derived neurotrophic factor (BDNF) which is important in synaptic plasticity and cognitive functions is reduced by stress. Therefore the BDNF Val66Met variant, which affects secretion of BDNF, may interact with early exposure to pain-related stress in children born very preterm, to differentially affect HPA regulation that in turn may be associated with altered cognitive performance. The aims of this study were to investigate whether in children born very preterm, the BDNF Val66Met variant modulates the association between neonatal pain-related stress and cortisol levels at age 7years, and if cortisol levels were related to cognitive function. Furthermore, we examined whether these relationships were sex-specific. Using a longitudinal cohort design, N=90 children born very preterm (24-32weeks gestation) were followed from birth to age 7years. Cortisol was assayed from hair as an index of cumulative stress and from saliva to measure reactivity to a cognitive challenge. BDNF Val66Met variant was genotyped at 7years using real-time polymerase chain reaction (PCR). Using generalized linear modeling, in boys with the Met allele, greater neonatal pain-related stress (adjusted for clinical risk factors) predicted lower hair cortisol (p=0.006) and higher reactivity salivary cortisol (p=0.002). In both boys and girls with the Met allele, higher salivary cortisol reactivity was correlated with lower IQ (r=-0.60; p=0.001) and poorer visual-motor integration (r=-0.48; p=0.008). Our findings show associations between lower BDNF availability (presence of the Met allele) and vulnerability to neonatal pain/stress in boys, but not girls. This exploratory study suggests new directions for research into possible mechanisms underlying how neonatal pain/stress is

Association between butyrylcholinesterase K variant and mild cognitive impairment in the Thai community-dwelling patients.

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Pongthanaracht, Natsalil; Yanarojana, Somchai; Pinthong, Darawan; Unchern, Supeenun; Thithapandha, Amnuay; Assantachai, Prasert; Supavilai, Porntip

2017-01-01

To study the association of the butyrylcholinesterase K variant (BChE-K) and the plasma BChE activity with mild cognitive impairment (MCI) in Thai community-dwelling patients. One hundred patients diagnosed with MCI and 100 control subjects were recruited from the community-dwelling setting in Bangkok, Thailand. The genotype and allele distributions of the BChE-K were determined by polymerase chain reaction and subsequent DNA sequencing. The BChE activity was measured in plasma according to the Ellman's method. The BChE-K allele frequencies in the Thai community-dwelling patients were in accordance with other ethnics. The BChE-K allele frequency in the control subjects (12%) was higher than that of MCI patients (5.5%), suggesting a protective role of BChE-K for MCI in the Thai community-dwelling patients. The BChE-K homozygotes were significantly associated with lower BChE activity. Our results suggested that the BChE-K may be implicated as a protective factor for MCI in the Thai community-dwelling patients, although a further study with a large sample size is warranted to confirm this.

A NOS1 variant implicated in cognitive performance influences evoked neural responses during a high density EEG study of early visual perception.

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O'Donoghue, Therese; Morris, Derek W; Fahey, Ciara; Da Costa, Andreia; Foxe, John J; Hoerold, Doreen; Tropea, Daniela; Gill, Michael; Corvin, Aiden; Donohoe, Gary

2012-05-01

The nitric oxide synthasase-1 gene (NOS1) has been implicated in mental disorders including schizophrenia and variation in cognition. The NOS1 variant rs6490121 identified in a genome wide association study of schizophrenia has recently been associated with variation in general intelligence and working memory in both patients and healthy participants. Whether this variant is also associated with variation in early sensory processing remains unclear. We investigated differences in the P1 visual evoked potential in a high density EEG study of 54 healthy participants. Given both NOS1's association with cognition and recent evidence that cognitive performance and P1 response are correlated, we investigated whether NOS1's effect on P1 response was independent of its effects on cognition using CANTAB's spatial working memory (SWM) task. We found that carriers of the previously identified risk "G" allele showed significantly lower P1 responses than non-carriers. We also found that while P1 response and SWM performance were correlated, NOS1 continued to explain a significant proportion of variation in P1 response even when its effects on cognition were accounted for. The schizophrenia implicated NOS1 variants rs6490121 influences visual sensory processing as measured by the P1 response, either as part of the gene's pleiotropic effects on multiple aspects of brain function, or because of a primary influence on sensory processing that mediates the effects already seen in higher cognitive processes. Copyright © 2011 Wiley-Liss, Inc.

Apolipoprotein e4 allele and cognitive decline in elderly men

NARCIS (Netherlands)

Feskens, E.J.M.; Havekes, L.M.; Kalmijn, S.; Knijff, P. de; Launer, L.J.; Kromhout, D.

1994-01-01

Objectives - To determine whether polymorphism of apolipoprotein E - notably, the e4 allele - predicts cognitive deterioration in the general population. Design - Population based cohort investigated in 1990 and in 1993. Setting - Zutphen, the Netherlands. Subjects - Representative cohort of 538

Association between allelic variants of the human glucocorticoid receptor gene and autoimmune diseases: A systematic review and meta-analysis.

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Herrera, Cristian; Marcos, Miguel; Carbonell, Cristina; Mirón-Canelo, José Antonio; Espinosa, Gerard; Cervera, Ricard; Chamorro, Antonio-Javier

2018-05-01

The human glucocorticoid receptor gene (NR3C1) is considered to play a role in the differences and sensitivities of the glucocorticoid response in individuals with autoimmune diseases. The objective of this study was to examine by means of a systematic review previous findings regarding allelic variants of NR3C1 in relation to the risk of developing systemic autoimmune diseases. Studies that analysed the genotype distribution of NR3C1 allelic variants among patients with systemic autoimmune diseases were retrieved. A meta-analysis was conducted with a random effects model. Odds ratios (ORs) and their confidence intervals (CIs) were calculated. In addition, sub-analysis by ethnicity, sensitivity analysis and tests for heterogeneity of the results were performed. Eleven studies met the inclusion criteria for meta-analysis. We found no evidence that the analysed NR3C1 polymorphisms, rs6198, rs56149945, and rs6189/rs6190, modulate the risk of developing a systemic autoimmune disease. Nonetheless, a protective role for the minor allele of rs41423247 was found among Caucasians (OR=0.78; 95% CI: 0.65, 0.92; P=0.004). A subgroup analysis according to underlying diseases revealed no significant association either for Behçet's disease or rheumatoid arthritis, while correlations between NR3C1 polymorphisms and disease activity or response to glucocorticoids could not be evaluated due to insufficient data. There is no clear evidence that the analysed NR3C1 allelic variants confer a risk for developing systemic autoimmune diseases although the minor G allele of rs41423247 may be protective among Caucasians. Copyright © 2018 Elsevier B.V. All rights reserved.

Allelic variants of melanocortin 3 receptor gene (MC3R) and weight loss in obesity

DEFF Research Database (Denmark)

L. Santos, José; De la Cruz, Rolando; Holst, Claus

2011-01-01

receptor gene (MC3R) have been associated with childhood obesity, higher BMI Z-score and elevated body fat percentage compared to non-carriers. The aim of this study is to assess the association in adults between allelic variants of MC3R with weight loss induced by energy-restricted diets.......The melanocortin system plays an important role in energy homeostasis. Mice genetically deficient in the melanocortin-3 receptor gene have a normal body weight with increased body fat, mild hypophagia compared to wild-type mice. In humans, Thr6Lys and Val81Ile variants of the melanocortin-3...

Haplotype block structure study of the CFTR gene. Most variants are associated with the M470 allele in several European populations.

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Pompei, Fiorenza; Ciminelli, Bianca Maria; Bombieri, Cristina; Ciccacci, Cinzia; Koudova, Monika; Giorgi, Silvia; Belpinati, Francesca; Begnini, Angela; Cerny, Milos; Des Georges, Marie; Claustres, Mireille; Ferec, Claude; Macek, Milan; Modiano, Guido; Pignatti, Pier Franco

2006-01-01

An average of about 1700 CFTR (cystic fibrosis transmembrane conductance regulator) alleles from normal individuals from different European populations were extensively screened for DNA sequence variation. A total of 80 variants were observed: 61 coding SNSs (results already published), 13 noncoding SNSs, three STRs, two short deletions, and one nucleotide insertion. Eight DNA variants were classified as non-CF causing due to their high frequency of occurrence. Through this survey the CFTR has become the most exhaustively studied gene for its coding sequence variability and, though to a lesser extent, for its noncoding sequence variability as well. Interestingly, most variation was associated with the M470 allele, while the V470 allele showed an 'extended haplotype homozygosity' (EHH). These findings make us suggest a role for selection acting either on the M470V itself or through an hitchhiking mechanism involving a second site. The possible ancient origin of the V allele in an 'out of Africa' time frame is discussed.

Allele Workbench: transcriptome pipeline and interactive graphics for allele-specific expression.

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Carol A Soderlund

Full Text Available Sequencing the transcriptome can answer various questions such as determining the transcripts expressed in a given species for a specific tissue or condition, evaluating differential expression, discovering variants, and evaluating allele-specific expression. Differential expression evaluates the expression differences between different strains, tissues, and conditions. Allele-specific expression evaluates expression differences between parental alleles. Both differential expression and allele-specific expression have been studied for heterosis (hybrid vigor, where the hybrid has improved performance over the parents for one or more traits. The Allele Workbench software was developed for a heterosis study that evaluated allele-specific expression for a mouse F1 hybrid using libraries from multiple tissues with biological replicates. This software has been made into a distributable package, which includes a pipeline, a Java interface to build the database, and a Java interface for query and display of the results. The required input is a reference genome, annotation file, and one or more RNA-Seq libraries with optional replicates. It evaluates allelic imbalance at the SNP and transcript level and flags transcripts with significant opposite directional allele-specific expression. The Java interface allows the user to view data from libraries, replicates, genes, transcripts, exons, and variants, including queries on allele imbalance for selected libraries. To determine the impact of allele-specific SNPs on protein folding, variants are annotated with their effect (e.g., missense, and the parental protein sequences may be exported for protein folding analysis. The Allele Workbench processing results in transcript files and read counts that can be used as input to the previously published Transcriptome Computational Workbench, which has a new algorithm for determining a trimmed set of gene ontology terms. The software with demo files is available

Investigating the relationship between FMR1 allele length and cognitive ability in children: a subtle effect of the normal allele range on the normal ability range?

Science.gov (United States)

Loat, C S; Craig, G; Plomin, R; Craig, I W

2006-09-01

The FMR1 gene contains a trinucleotide repeat tract which can expand from a normal size of around 30 repeats to over 200 repeats, causing mental retardation (Fragile X Syndrome). Evidence suggests that premutation males (55-200 repeats) are susceptible to a late-onset tremor/ataxia syndrome and females to premature ovarian failure, and that intermediate alleles ( approximately 41-55 repeats) and premutations may be in excess in samples with special educational needs. We explored the relationship between FMR1 allele length and cognitive ability in 621 low ability and control children assessed at 4 and 7 years, as well as 122 students with high IQ. The low and high ability and control samples showed no between-group differences in incidence of longer alleles. In males there was a significant negative correlation between allele length and non-verbal ability at 4 years (p = 0.048), academic achievement in maths (p = 0.003) and English (p = 0.011) at 7 years, and IQ in the high ability group (p = 0.018). There was a significant negative correlation between allele length and a standardised score for IQ and general cognitive ability at age 7 in the entire male sample (p = 0.002). This suggests that, within the normal spectrum of allele length, increased repeat numbers may have a limiting influence on cognitive performance.

Dyslexia risk variant rs600753 is linked with dyslexia-specific differential allelic expression of DYX1C1

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Bent Müller

2018-02-01

Full Text Available Abstract An increasing number of genetic variants involved in dyslexia development were discovered during the last years, yet little is known about the molecular functional mechanisms of these SNPs. In this study we investigated whether dyslexia candidate SNPs have a direct, disease-specific effect on local expression levels of the assumed target gene by using a differential allelic expression assay. In total, 12 SNPs previously associated with dyslexia and related phenotypes were suitable for analysis. Transcripts corresponding to four SNPs were sufficiently expressed in 28 cell lines originating from controls and a family affected by dyslexia. We observed a significant effect of rs600753 on expression levels of DYX1C1 in forward and reverse sequencing approaches. The expression level of the rs600753 risk allele was increased in the respective seven cell lines from members of the dyslexia family which might be due to a disturbed transcription factor binding sites. When considering our results in the context of neuroanatomical dyslexia-specific findings, we speculate that this mechanism may be part of the pathomechanisms underlying the dyslexia-specific brain phenotype. Our results suggest that allele-specific DYX1C1 expression levels depend on genetic variants of rs600753 and contribute to dyslexia. However, these results are preliminary and need replication.

The cognitive impact of the ANK3 risk variant for bipolar disorder: initial evidence of selectivity to signal detection during sustained attention.

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Gaia Ruberto

Full Text Available BACKGROUND: Abnormalities in cognition have been reported in patients with Bipolar Disorder (BD and their first degree relatives, suggesting that susceptibility genes for BD may impact on cognitive processes. Recent genome-wide genetic studies have reported a strong association with BD in a single nucleotide polymorphism (SNP (rs10994336 within ANK3, which codes for Ankyrin 3. This protein is involved in facilitating the propagation of action potentials by regulating the assembly of sodium gated ion channels. Since ANK3 influences the efficiency of transmission of neuronal impulses, allelic variation in this gene may have widespread cognitive effects. Preclinical data suggest that this may principally apply to sequential signal detection, a core process of sustained attention. METHODOLOGY/PRINCIPAL FINDINGS: One hundred and eighty-nine individuals of white British descent were genotyped for the ANK3 rs10994336 polymorphism and received diagnostic interviews and comprehensive neurocognitive assessment of their general intellectual ability, memory, decision making, response inhibition and sustained attention. Participants comprised euthymic BD patients (n = 47, their unaffected first-degree relatives (n = 75 and healthy controls (n = 67. The risk allele T was associated with reduced sensitivity in target detection (p = 0.0004 and increased errors of commission (p = 0.0018 during sustained attention regardless of diagnosis. We found no effect of the ANK3 genotype on general intellectual ability, memory, decision making and response inhibition. CONCLUSIONS/SIGNIFICANCE: Our results suggest that allelic variation in ANK3 impacts cognitive processes associated with signal detection and this mechanism may relate to risk for BD. However, our results require independent replication and confirmation that ANK3 (rs10994336 is a direct functional variant.

Multimer Formation Explains Allelic Suppression of PRDM9 Recombination Hotspots.

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Baker, Christopher L; Petkova, Pavlina; Walker, Michael; Flachs, Petr; Mihola, Ondrej; Trachtulec, Zdenek; Petkov, Petko M; Paigen, Kenneth

2015-09-01

Genetic recombination during meiosis functions to increase genetic diversity, promotes elimination of deleterious alleles, and helps assure proper segregation of chromatids. Mammalian recombination events are concentrated at specialized sites, termed hotspots, whose locations are determined by PRDM9, a zinc finger DNA-binding histone methyltransferase. Prdm9 is highly polymorphic with most alleles activating their own set of hotspots. In populations exhibiting high frequencies of heterozygosity, questions remain about the influences different alleles have in heterozygous individuals where the two variant forms of PRDM9 typically do not activate equivalent populations of hotspots. We now find that, in addition to activating its own hotspots, the presence of one Prdm9 allele can modify the activity of hotspots activated by the other allele. PRDM9 function is also dosage sensitive; Prdm9+/- heterozygous null mice have reduced numbers and less active hotspots and increased numbers of aberrant germ cells. In mice carrying two Prdm9 alleles, there is allelic competition; the stronger Prdm9 allele can partially or entirely suppress chromatin modification and recombination at hotspots of the weaker allele. In cell cultures, PRDM9 protein variants form functional heteromeric complexes which can bind hotspots sequences. When a heteromeric complex binds at a hotspot of one PRDM9 variant, the other PRDM9 variant, which would otherwise not bind, can still methylate hotspot nucleosomes. We propose that in heterozygous individuals the underlying molecular mechanism of allelic suppression results from formation of PRDM9 heteromers, where the DNA binding activity of one protein variant dominantly directs recombination initiation towards its own hotspots, effectively titrating down recombination by the other protein variant. In natural populations with many heterozygous individuals, allelic competition will influence the recombination landscape.

Allelic diversity of the Plasmodium falciparum erythrocyte membrane protein 1 entails variant-specific red cell surface epitopes.

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Inès Vigan-Womas

Full Text Available The clonally variant Plasmodium falciparum PfEMP1 adhesin is a virulence factor and a prime target of humoral immunity. It is encoded by a repertoire of functionally differentiated var genes, which display architectural diversity and allelic polymorphism. Their serological relationship is key to understanding the evolutionary constraints on this gene family and rational vaccine design. Here, we investigated the Palo Alto/VarO and IT4/R29 and 3D7/PF13_003 parasites lines. VarO and R29 form rosettes with uninfected erythrocytes, a phenotype associated with severe malaria. They express an allelic Cys2/group A NTS-DBL1α(1 PfEMP1 domain implicated in rosetting, whose 3D7 ortholog is encoded by PF13_0003. Using these three recombinant NTS-DBL1α(1 domains, we elicited antibodies in mice that were used to develop monovariant cultures by panning selection. The 3D7/PF13_0003 parasites formed rosettes, revealing a correlation between sequence identity and virulence phenotype. The antibodies cross-reacted with the allelic domains in ELISA but only minimally with the Cys4/group B/C PFL1955w NTS-DBL1α. By contrast, they were variant-specific in surface seroreactivity of the monovariant-infected red cells by FACS analysis and in rosette-disruption assays. Thus, while ELISA can differentiate serogroups, surface reactivity assays define the more restrictive serotypes. Irrespective of cumulated exposure to infection, antibodies acquired by humans living in a malaria-endemic area also displayed a variant-specific surface reactivity. Although seroprevalence exceeded 90% for each rosetting line, the kinetics of acquisition of surface-reactive antibodies differed in the younger age groups. These data indicate that humans acquire an antibody repertoire to non-overlapping serotypes within a serogroup, consistent with an antibody-driven diversification pressure at the population level. In addition, the data provide important information for vaccine design, as

Rarity of the Alzheimer Disease–Protective APP A673T Variant in the United States

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Wang, Li-San; Naj, Adam C.; Graham, Robert R.; Crane, Paul K.; Kunkle, Brian W.; Cruchaga, Carlos; Gonzalez Murcia, Josue D.; Cannon-Albright, Lisa; Baldwin, Clinton T.; Zetterberg, Henrik; Blennow, Kaj; Kukull, Walter A.; Faber, Kelley M.; Schupf, Nicole; Norton, Maria C.; Tschanz, JoAnn T.; Munger, Ronald G.; Corcoran, Christopher D.; Rogaeva, Ekaterina; Lin, Chiao-Feng; Dombroski, Beth A.; Cantwell, Laura B.; Partch, Amanda; Valladares, Otto; Hakonarson, Hakon; St George-Hyslop, Peter; Green, Robert C.; Goate, Alison M.; Foroud, Tatiana M.; Carney, Regina M.; Larson, Eric B.; Behrens, Timothy W.; Kauwe, John S. K.; Haines, Jonathan L.; Farrer, Lindsay A.; Pericak-Vance, Margaret A.; Mayeux, Richard; Schellenberg, Gerard D.

2015-01-01

IMPORTANCE Recently, a rare variant in the amyloid precursor protein gene (APP) was described in a population from Iceland. This variant, in which alanine is replaced by threonine at position 673 (A673T), appears to protect against late-onset Alzheimer disease (AD). We evaluated the frequency of this variant in AD cases and cognitively normal controls to determine whether this variant will significantly contribute to risk assessment in individuals in the United States. OBJECTIVE To determine the frequency of the APP A673T variant in a large group of elderly cognitively normal controls and AD cases from the United States and in 2 case-control cohorts from Sweden. DESIGN, SETTING, AND PARTICIPANTS Case-control association analysis of variant APP A673T in US and Swedish white individuals comparing AD cases with cognitively intact elderly controls. Participants were ascertained at multiple university-associated medical centers and clinics across the United States and Sweden by study-specific sampling methods. They were from case-control studies, community-based prospective cohort studies, and studies that ascertained multiplex families from multiple sources. MAIN OUTCOMES AND MEASURES Genotypes for the APP A673T variant were determined using the Infinium HumanExome V1 Beadchip (Illumina, Inc) and by TaqMan genotyping (Life Technologies). RESULTS The A673T variant genotypes were evaluated in 8943 US AD cases, 10 480 US cognitively normal controls, 862 Swedish AD cases, and 707 Swedish cognitively normal controls. We identified 3 US individuals heterozygous for A673T, including 1 AD case (age at onset, 89 years) and 2 controls (age at last examination, 82 and 77 years). The remaining US samples were homozygous for the alanine (A673) allele. In the Swedish samples, 3 controls were heterozygous for A673T and all AD cases were homozygous for the A673 allele. We also genotyped a US family previously reported to harbor the A673T variant and found a mother-daughter pair, both

Variant mannose-binding lectin alleles are not associated with susceptibility to or outcome of invasive pneumococcal infection in randomly included patients

DEFF Research Database (Denmark)

Kronborg, Gitte; Weis, Nina; Madsen, Hans O

2002-01-01

for pneumococcal infections. To assess the influence of MBL genotypes on the course and outcome of invasive pneumococcal disease, clinical data for 141 adult patients were collected prospectively and their genotypes were determined. All patients included had positive blood cultures for Streptococcus pneumoniae....... The distribution of variant MBL alleles related to low MBL serum concentrations was similar among the patients and healthy individuals, and MBL genotype was not associated with infection outcome. Thus, in a random adult population with invasive pneumococcal infection, MBL does not seem to play a role......Invasive pneumococcal disease is a serious infection that primarily affects very young children and elderly or immunocompromised individuals but also affects previously healthy people. Variant mannose-binding lectin (MBL) alleles are associated with recurrent infections and may be a risk factor...

Cytotoxic T lymphocyte-Associated Antigen +49G Variant Confers Risk for Anti-CCP- and Rheumatoid Factor-Positive Type of Rheumatoid Arthritis Only in Combination with CT60∗G Allele

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Bernadett Farago

2010-01-01

Full Text Available Controversial observations have been published on the association of the cytotoxic T lymphocyte associated antigen gene's variants with rheumatoid arthritis (RA. After genotyping 428 patients and 230 matched controls, the prevalence of the CT60∗G allele was more frequent in RF- and/or anti-CCP-seropositive RApatients, compared to the healthy controls (P<.001. Regression analysis revealed that the CT60∗G allele is a possible predisposing factor for RA in these subgroups. No accumulation of the +49∗G allele was found among patients, and this variant was not found to correlate with RA. Assaying the possible genotype variations, the +49∗G-CT60∗G allelic combination was accumulated in seropositive RA-subtypes, and was associated with the risk of RA (OR=1.73, P=.001 for the whole RA-population. Although the +49∗G allele did not mean a predisposition to RA alone, in combination with CT60∗G it, also conferred risk, suggesting that the +49A/G variant is associated with the risk of RA only in certain haplotypes.

Common genetic variants associated with thyroid function may be risk alleles for Hashimoto's disease and Graves' disease.

Science.gov (United States)

Campbell, Purdey; Brix, Thomas H; Wilson, Scott G; Ward, Lynley C; Hui, Jennie; Beilby, John P; Hegedüs, Laszlo; Walsh, John P

2015-02-14

Recent studies have identified common genetic variants associated with TSH, free T4 and thyroid peroxidase antibodies, but it is unclear whether these differ between patients with Hashimoto's disease and Graves' disease. To examine whether 11 common genetic variants differ between Graves' disease and Hashimoto's disease. We genotyped 11 common variants in a discovery cohort of 203 Australian patients with autoimmune thyroid disease (AITD). Two variants with significant or suggestive associations were analysed in a replication cohort of 384 Danish patients. For rs753760 (PDE10A), the minor allele frequency in Graves' disease and Hashimoto's disease was 0·38 vs. 0·23, respectively, (P = 6·42 × 10 -4 ) in the discovery cohort, 0·29 vs. 0·24 (P = 0·147) in the replication cohort and 0·32 vs. 0·24 in combined analysis (P = 0·0021; all analyses adjusted for sex). In healthy controls from Busselton, the frequency was 0·29, significantly different from Hashimoto's disease but not Graves' disease. For rs4889009 (MAF gene region), the frequency of the minor G-allele in Graves' disease and Hashimoto's disease was 0·48 vs. 0·36 (P = 0·0156) in the discovery cohort, 0·48 vs. 0·34 (P = 1·83 × 10 -4 ) in the replication cohort and 0·48 vs. 0·35 in the combined analysis (P = 7·53 × 10 -6 ); in controls, the frequency was 0·38, significantly different from Graves' disease but not Hashimoto's disease. After further adjustment for smoking, associations with rs4889009 remained significant, whereas those with rs753760 were not. Common variants in PDE10A and MAF gene regions may influence whether patients with AITD develop Graves' disease or Hashimoto's disease. © 2015 John Wiley & Sons Ltd.

Influence of kynurenine 3-monooxygenase (KMO) gene polymorphism on cognitive function in schizophrenia.

Science.gov (United States)

Wonodi, Ikwunga; McMahon, Robert P; Krishna, Nithin; Mitchell, Braxton D; Liu, Judy; Glassman, Matthew; Hong, L Elliot; Gold, James M

2014-12-01

Cognitive deficits compromise quality of life and productivity for individuals with schizophrenia and have no effective treatments. Preclinical data point to the kynurenine pathway of tryptophan metabolism as a potential target for pro-cognitive drug development. We have previously demonstrated association of a kynurenine 3-monooxygenase (KMO) gene variant with reduced KMO gene expression in postmortem schizophrenia cortex, and neurocognitive endophenotypic deficits in a clinical sample. KMO encodes kynurenine 3-monooxygenase (KMO), the rate-limiting microglial enzyme of cortical kynurenine metabolism. Aberration of the KMO gene might be the proximal cause of impaired cortical kynurenine metabolism observed in schizophrenia. However, the relationship between KMO variation and cognitive function in schizophrenia is unknown. This study examined the effects of the KMO rs2275163C>T C (risk) allele on cognitive function in schizophrenia. We examined the association of KMO polymorphisms with general neuropsychological performance and P50 gating in a sample of 150 schizophrenia and 95 healthy controls. Consistent with our original report, the KMO rs2275163C>T C (risk) allele was associated with deficits in general neuropsychological performance, and this effect was more marked in schizophrenia compared with controls. Additionally, the C (Arg452) allele of the missense rs1053230C>T variant (KMO Arg452Cys) showed a trend effect on cognitive function. Neither variant affected P50 gating. These data suggest that KMO variation influences a range of cognitive domains known to predict functional outcome. Extensive molecular characterization of this gene would elucidate its role in cognitive function with implications for vertical integration with basic discovery. Copyright © 2014 Elsevier B.V. All rights reserved.

Cytochrome P450 2D6 variants in a Caucasian population: Allele frequencies and phenotypic consequences

Energy Technology Data Exchange (ETDEWEB)

Sachse, C.; Brockmoeller, J.; Bauer, S.; Roots, I. [Humboldt Univ., Berlin (Germany)

1997-02-01

Cytochrome P450 2D6 (CYP2D6) metabolizes many important drugs. CYP2D6 activity ranges from complete deficiency to ultrafast metabolism, depending on at least 16 different known alleles. Their frequencies were determined in 589 unrelated German volunteers and correlated with enzyme activity measured by phenotyping with dextromethorphan or debrisoquine. For genotyping, nested PCR-RFLP tests from a PCR amplificate of the entire CYP2D6 gene were developed. The frequency of the CYP2D6*1 allele coding for extensive metabolizer (EM) phenotype was .364. The alleles coding for slightly (CYP2D6*2) or moderately (*9 and *10) reduced activity (intermediate metabolizer phenotype [IM]) showed frequencies of .324, .018, and .015, respectively. By use of novel PCR tests for discrimination, CYP2D6 gene duplication alleles were found with frequencies of.005 (*1 x 2), .013 (* 2 x 2), and .001 (*4 x 2). Frequencies of alleles with complete deficiency (poor metabolizer phenotype [PM]) were .207 (*4), .020 (*3 and *5), .009 (*6), and .001 (*7, *15, and *16). The defective CYP2D6 alleles *8, *11, *12, *13, and *14 were not found. All 41 PMs (7.0%) in this sample were explained by five mutations detected by four PCR-RFLP tests, which may suffice, together with the gene duplication test, for clinical prediction of CYP2D6 capacity. Three novel variants of known CYP2D6 alleles were discovered: *1C (T{sub 1957}C), *2B (additional C{sub 2558}T), and *4E (additional C{sub 2938}T). Analysis of variance showed significant differences in enzymatic activity measured by the dextromethorphan metabolic ratio (MR) between carriers of EN/PM (mean MR = .006) and IM/PM (mean MR = .014) alleles and between carriers of one (mean MR = .009) and two (mean MR = .003) functional alleles. The results of this study provide a solid basis for prediction of CYP2D6 capacity, as required in drug research and routine drug treatment. 35 refs., 4 figs., 5 tabs.

Influence of kynurenine 3-monooxygenase (KMO) gene polymorphism on cognitive function in schizophrenia✰,✰✰

Science.gov (United States)

Wonodi, Ikwunga; McMahon, Robert P.; Krishna, Nithin; Mitchell, Braxton D.; Liu, Judy; Glassman, Matthew; Hong, L. Elliot; Gold, James M.

2015-01-01

Background Cognitive deficits compromise quality of life and productivity for individuals with schizophrenia and have no effective treatments. Preclinical data point to the kynurenine pathway of tryptophan metabolism as a potential target for pro-cognitive drug development. We have previously demonstrated association of a kynurenine 3-monooxygenase (KMO) gene variant with reduced KMO gene expression in postmortem schizophrenia cortex, and neurocognitive endophenotypic deficits in a clinical sample. KMO encodes kynurenine 3-monooxygenase (KMO), the rate-limiting microglial enzyme of cortical kynurenine metabolism. Aberration of the KMO gene might be the proximal cause of impaired cortical kynurenine metabolism observed in schizophrenia. However, the relationship between KMO variation and cognitive function in schizophrenia is unknown. This study examined the effects of the KMO rs2275163C>T C (risk) allele on cognitive function in schizophrenia. Methods We examined the association of KMO polymorphisms with general neuropsychological performance and P50 gating in a sample of 150 schizophrenia and 95 healthy controls. Results Consistent with our original report, the KMO rs2275163C>T C (risk) allele was associated with deficits in general neuropsychological performance, and this effect was more marked in schizophrenia compared with controls. Additionally, the C (Arg452) allele of the missense rs1053230C>T variant (KMO Arg452Cys) showed a trend effect on cognitive function. Neither variant affected P50 gating. Conclusions These data suggest that KMO variation influences a range of cognitive domains known to predict functional outcome. Extensive molecular characterization of this gene would elucidate its role in cognitive function with implications for vertical integration with basic discovery. PMID:25464917

Allele-dependent differences in quorum-sensing dynamics result in variant expression of virulence genes in Staphylococcus aureus.

Science.gov (United States)

Geisinger, Edward; Chen, John; Novick, Richard P

2012-06-01

Agr is an autoinducing, quorum-sensing system that functions in many Gram-positive species and is best characterized in the pathogen Staphylococcus aureus, in which it is a global regulator of virulence gene expression. Allelic variations in the agr genes have resulted in the emergence of four quorum-sensing specificity groups in S. aureus, which correlate with different strain pathotypes. The basis for these predilections is unclear but is hypothesized to involve the phenomenon of quorum-sensing interference between strains of different agr groups, which may drive S. aureus strain isolation and divergence. Whether properties intrinsic to each agr allele directly influence virulence phenotypes within S. aureus is unknown. In this study, we examined group-specific differences in agr autoinduction and virulence gene regulation by utilizing congenic strains, each harboring a unique S. aureus agr allele, enabling a dissection of agr locus-dependent versus genotype-dependent effects on quorum-sensing dynamics and virulence factor production. Employing a reporter fusion to the principal agr promoter, P3, we observed allele-dependent differences in the timing and magnitude of agr activation. These differences were mediated by polymorphisms within the agrBDCA genes and translated to significant variations in the expression of a key transcriptional regulator, Rot, and of several important exoproteins and surface factors involved in pathogenesis. This work uncovers the contribution of divergent quorum-sensing alleles to variant expression of virulence determinants within a bacterial species.

Genetic Variants in KLOTHO Associate With Cognitive Function in the Oldest Old Group

DEFF Research Database (Denmark)

Mengel-From, Jonas; Sørensen, Mette; Nygaard, Marianne

2016-01-01

, for example, growth factor signaling. In the present study, 19 tagging gene variants in KL were studied in relation to 2 measures of cognitive function, a 5-item cognitive composite score and the Mini Mental State Examination, in 1,480 Danes 92-100 years of age. We found that heterozygotes for the previously......Decline in cognitive abilities is a major concern in aging individuals. A potential important factor for functioning of the central nervous system in late-life stages is the KLOTHO (KL) gene. KL is expressed in various organs including the brain and is involved in multiple biological processes...... reported KL-VS had poorer cognitive function than noncarriers. Two other variants positioned in the 5' end of the gene, rs398655 and rs562020, were associated with better cognitive function independently of KL-VS, and the common haplotype AG was associated with poorer cognition, consistently across two...

RHD alleles in the Tunisian population

Science.gov (United States)

Ouchari, Mouna; Jemni-Yaacoub, Saloua; Chakroun, Taher; Abdelkefi, Saida; Houissa, Batoul; Hmida, Slama

2013-01-01

Background: A comprehensive survey of RHD alleles in Tunisia population was lacking. The aim of this study was to use a multiplex RHD typing assay for simultaneous detection of partial D especially with RHD/RHCE deoxyribonucleic acid (DNA) sequence exchange mechanism and some weak D alleles. Materials and Methods: Six RHD specific primer sets were designed to amplify RHD exons 3, 4, 5, 6, 7 and 9. DNA from 2000 blood donors (1777 D+ and 223 D-) from several regions was selected for RHD genotyping using a PCR multiplex assay. Further molecular investigations were done to characterize the RHD variants that were identified by the PCR multiplex assay. Results: In the 1777 D+ samples, only 10 individuals showed the absence of amplification of exons 4 and 5 that were subsequently identified by PCR-SSP as weak D type 4 variants. No hybrid allele was detected. In the 223 D-, RHD amplification of some exons was observed only in 5 samples: 4 individuals expressed only RHD exon 9, and one subject lacking exons 4 and 5. These samples were then screened by PCR-SSPs on d(C) ces and weak D type 4, respectively. Conclusion: The weak D type 4 appears to be the most common D variant allele. We have not found any partial D variant. Findings also indicated that RHD gene deletion is the most prevalent cause of the D- phenotype in the Tunisian population. PMID:24014941

Common variants of the genes encoding erythropoietin and its receptor modulate cognitive performance in schizophrenia

DEFF Research Database (Denmark)

Kästner, Anne; Grube, Sabrina; El-Kordi, Ahmed

2012-01-01

-term memory readouts, with one particular combination of genotypes superior to all others (p 800), these associations were confirmed. A matching preclinical study with mice demonstrated cognitive processing speed and memory enhanced upon transgenic......Erythropoietin (EPO) improves cognitive performance in clinical studies and rodent experiments. We hypothesized that an intrinsic role of EPO for cognition exists, with particular relevance in situations of cognitive decline, which is reflected by associations of EPO and EPO receptor (EPOR......) genotypes with cognitive functions. To prove this hypothesis, schizophrenic patients (N > 1000) were genotyped for 5' upstream-located gene variants, EPO SNP rs1617640 (T/G) and EPORSTR(GA)(n). Associations of these variants were obtained for cognitive processing speed, fine motor skills and short...

Complex analysis of urate transporters SLC2A9, SLC22A12 and functional characterization of non-synonymous allelic variants of GLUT9 in the Czech population: no evidence of effect on hyperuricemia and gout.

Science.gov (United States)

Hurba, Olha; Mancikova, Andrea; Krylov, Vladimir; Pavlikova, Marketa; Pavelka, Karel; Stibůrková, Blanka

2014-01-01

Using European descent Czech populations, we performed a study of SLC2A9 and SLC22A12 genes previously identified as being associated with serum uric acid concentrations and gout. This is the first study of the impact of non-synonymous allelic variants on the function of GLUT9 except for patients suffering from renal hypouricemia type 2. The cohort consisted of 250 individuals (150 controls, 54 nonspecific hyperuricemics and 46 primary gout and/or hyperuricemia subjects). We analyzed 13 exons of SLC2A9 (GLUT9 variant 1 and GLUT9 variant 2) and 10 exons of SLC22A12 by PCR amplification and sequenced directly. Allelic variants were prepared and their urate uptake and subcellular localization were studied by Xenopus oocytes expression system. The functional studies were analyzed using the non-parametric Wilcoxon and Kruskall-Wallis tests; the association study used the Fisher exact test and linear regression approach. We identified a total of 52 sequence variants (12 unpublished). Eight non-synonymous allelic variants were found only in SLC2A9: rs6820230, rs2276961, rs144196049, rs112404957, rs73225891, rs16890979, rs3733591 and rs2280205. None of these variants showed any significant difference in the expression of GLUT9 and in urate transport. In the association study, eight variants showed a possible association with hyperuricemia. However, seven of these were in introns and the one exon located variant, rs7932775, did not show a statistically significant association with serum uric acid concentration. Our results did not confirm any effect of SLC22A12 and SLC2A9 variants on serum uric acid concentration. Our complex approach using association analysis together with functional and immunohistochemical characterization of non-synonymous allelic variants did not show any influence on expression, subcellular localization and urate uptake of GLUT9.

Association of breast cancer risk with genetic variants showing differential allelic expression: Identification of a novel breast cancer susceptibility locus at 4q21

NARCIS (Netherlands)

Y. Hamdi (Yosr); Soucy, P. (Penny); Adoue, V. (Véronique); K. Michailidou (Kyriaki); S. Canisius (Sander); Lemaçon, A. (Audrey); A. Droit (Arnaud); I.L. Andrulis (Irene); H. Anton-Culver (Hoda); Arndt, V. (Volker); Baynes, C. (Caroline); C. Blomqvist (Carl); N.V. Bogdanova (Natalia); S.E. Bojesen (Stig); M.K. Bolla (Manjeet K.); B. Bonnani (Bernardo); A.-L. Borresen-Dale (Anne-Lise); J.S. Brand (Judith S.); H. Brauch (Hiltrud); Brenner, H. (Hermann); A. Broeks (Annegien); B. Burwinkel (Barbara); J. Chang-Claude (Jenny); Couch, F.J. (Fergus J.); A. Cox (Angela); S.S. Cross (Simon); K. Czene (Kamila); H. Darabi (Hatef); J. Dennis (Joe); P. Devilee (Peter); T. Dörk (Thilo); I. dos Santos Silva (Isabel); M. Eriksson (Mats); P.A. Fasching (Peter); J.D. Figueroa (Jonine); H. Flyger (Henrik); M. García-Closas (Montserrat); Giles, G.G. (Graham G.); M.S. Goldberg (Mark); A. González-Neira (Anna); G. Grenaker Alnæs (Grethe); P. Guénel (Pascal); L. Haeberle (Lothar); C.A. Haiman (Christopher); U. Hamann (Ute); Hallberg, E. (Emily); M.J. Hooning (Maartje); J.L. Hopper (John); A. Jakubowska (Anna); M. Jones (Michael); M. Kabisch (Maria); V. Kataja (Vesa); Lambrechts, D. (Diether); L. Le Marchand (Loic); A. Lindblom (Annika); J. Lubinski (Jan); A. Mannermaa (Arto); M. Maranian (Melanie); S. Margolin (Sara); Marme, F. (Frederik); R.L. Milne (Roger); S.L. Neuhausen (Susan); H. Nevanlinna (Heli); P. Neven (Patrick); C. Olswold (Curtis); J. Peto (Julian); Plaseska-Karanfilska, D. (Dijana); K. Pykäs (Katri); P. Radice (Paolo); A. Rudolph (Anja); E.J. Sawyer (Elinor); M.K. Schmidt (Marjanka); X.-O. Shu (Xiao-Ou); M.C. Southey (Melissa); A.J. Swerdlow (Anthony ); R.A.E.M. Tollenaar (Rob); I.P. Tomlinson (Ian); D. Torres (Diana); T. Truong (Thérèse); C. Vachon (Celine); A.M.W. van den Ouweland (Ans); Q. Wang (Qin); R. Winqvist (Robert); W. Zheng (Wei); J. Benítez (Javier); G. Chenevix-Trench (Georgia); A.M. Dunning (Alison); P.D.P. Pharoah (Paul); Kristensen, V. (Vessela); P. Hall (Per); D.F. Easton (Douglas); T. Pastinen (Tomi); S. Nord (Silje); J. Simard (Jacques)

2016-01-01

textabstractThere are significant inter-individual differences in the levels of gene expression. Through modulation of gene expression, cis-acting variants represent an important source of phenotypic variation. Consequently, cis-regulatory SNPs associated with differential allelic expression are

Immunogenicity of Recombinant Proteins Consisting of Plasmodium vivax Circumsporozoite Protein Allelic Variant-Derived Epitopes Fused with Salmonella enterica Serovar Typhimurium Flagellin

Science.gov (United States)

Leal, Monica Teixeira Andrade; Camacho, Ariane Guglielmi Ariza; Teixeira, Laís Helena; Bargieri, Daniel Youssef; Soares, Irene Silva; Tararam, Cibele Aparecida

2013-01-01

A Plasmodium falciparum circumsporozoite protein (CSP)-based recombinant fusion vaccine is the first malaria vaccine to reach phase III clinical trials. Resistance to infection correlated with the production of antibodies to the immunodominant central repeat region of the CSP. In contrast to P. falciparum, vaccine development against the CSP of Plasmodium vivax malaria is far behind. Based on this gap in our knowledge, we generated a recombinant chimeric protein containing the immunodominant central repeat regions of the P. vivax CSP fused to Salmonella enterica serovar Typhimurium-derived flagellin (FliC) to activate the innate immune system. The recombinant proteins that were generated contained repeat regions derived from each of the 3 different allelic variants of the P. vivax CSP or a fusion of regions derived from each of the 3 allelic forms. Mice were subcutaneously immunized with the fusion proteins alone or in combination with the Toll-like receptor 3 (TLR-3) agonist poly(I·C), and the anti-CSP serum IgG response was measured. Immunization with a mixture of the 3 recombinant proteins, each containing immunodominant epitopes derived from a single allelic variant, rather than a single recombinant protein carrying a fusion of regions derived from each of 3 allelic forms elicited a stronger immune response. This response was independent of TLR-4 but required TLR-5/MyD88 activation. Antibody titers significantly increased when poly(I·C) was used as an adjuvant with a mixture of the 3 recombinant proteins. These recombinant fusion proteins are novel candidates for the development of an effective malaria vaccine against P. vivax. PMID:23863502

Association of breast cancer risk with genetic variants showing differential allelic expression: Identification of a novel breast cancer susceptibility locus at 4q21

Science.gov (United States)

Adoue, Véronique; Michailidou, Kyriaki; Canisius, Sander; Lemaçon, Audrey; Droit, Arnaud; Andrulis, Irene L; Anton-Culver, Hoda; Arndt, Volker; Baynes, Caroline; Blomqvist, Carl; Bogdanova, Natalia V.; Bojesen, Stig E.; Bolla, Manjeet K.; Bonanni, Bernardo; Borresen-Dale, Anne-Lise; Brand, Judith S.; Brauch, Hiltrud; Brenner, Hermann; Broeks, Annegien; Burwinkel, Barbara; Chang-Claude, Jenny; Couch, Fergus J.; Cox, Angela; Cross, Simon S.; Czene, Kamila; Darabi, Hatef; Dennis, Joe; Devilee, Peter; Dörk, Thilo; Dos-Santos-Silva, Isabel; Eriksson, Mikael; Fasching, Peter A.; Figueroa, Jonine; Flyger, Henrik; García-Closas, Montserrat; Giles, Graham G.; Goldberg, Mark S.; González-Neira, Anna; Grenaker-Alnæs, Grethe; Guénel, Pascal; Haeberle, Lothar; Haiman, Christopher A.; Hamann, Ute; Hallberg, Emily; Hooning, Maartje J.; Hopper, John L.; Jakubowska, Anna; Jones, Michael; Kabisch, Maria; Kataja, Vesa; Lambrechts, Diether; Marchand, Loic Le; Lindblom, Annika; Lubinski, Jan; Mannermaa, Arto; Maranian, Mel; Margolin, Sara; Marme, Frederik; Milne, Roger L.; Neuhausen, Susan L.; Nevanlinna, Heli; Neven, Patrick; Olswold, Curtis; Peto, Julian; Plaseska-Karanfilska, Dijana; Pylkäs, Katri; Radice, Paolo; Rudolph, Anja; Sawyer, Elinor J.; Schmidt, Marjanka K.; Shu, Xiao-Ou; Southey, Melissa C.; Swerdlow, Anthony; Tollenaar, Rob A.E.M.; Tomlinson, Ian; Torres, Diana; Truong, Thérèse; Vachon, Celine; Van Den Ouweland, Ans M. W.; Wang, Qin; Winqvist, Robert; Investigators, kConFab/AOCS; Zheng, Wei; Benitez, Javier; Chenevix-Trench, Georgia; Dunning, Alison M.; Pharoah, Paul D. P.; Kristensen, Vessela; Hall, Per; Easton, Douglas F.; Pastinen, Tomi; Nord, Silje; Simard, Jacques

2016-01-01

There are significant inter-individual differences in the levels of gene expression. Through modulation of gene expression, cis-acting variants represent an important source of phenotypic variation. Consequently, cis-regulatory SNPs associated with differential allelic expression are functional candidates for further investigation as disease-causing variants. To investigate whether common variants associated with differential allelic expression were involved in breast cancer susceptibility, a list of genes was established on the basis of their involvement in cancer related pathways and/or mechanisms. Thereafter, using data from a genome-wide map of allelic expression associated SNPs, 313 genetic variants were selected and their association with breast cancer risk was then evaluated in 46,451 breast cancer cases and 42,599 controls of European ancestry ascertained from 41 studies participating in the Breast Cancer Association Consortium. The associations were evaluated with overall breast cancer risk and with estrogen receptor negative and positive disease. One novel breast cancer susceptibility locus on 4q21 (rs11099601) was identified (OR = 1.05, P = 5.6x10-6). rs11099601 lies in a 135 kb linkage disequilibrium block containing several genes, including, HELQ, encoding the protein HEL308 a DNA dependant ATPase and DNA Helicase involved in DNA repair, MRPS18C encoding the Mitochondrial Ribosomal Protein S18C and FAM175A (ABRAXAS), encoding a BRCA1 BRCT domain-interacting protein involved in DNA damage response and double-strand break (DSB) repair. Expression QTL analysis in breast cancer tissue showed rs11099601 to be associated with HELQ (P = 8.28x10-14), MRPS18C (P = 1.94x10-27) and FAM175A (P = 3.83x10-3), explaining about 20%, 14% and 1%, respectively of the variance inexpression of these genes in breast carcinomas. PMID:27792995

Association of breast cancer risk with genetic variants showing differential allelic expression: Identification of a novel breast cancer susceptibility locus at 4q21.

Science.gov (United States)

Hamdi, Yosr; Soucy, Penny; Adoue, Véronique; Michailidou, Kyriaki; Canisius, Sander; Lemaçon, Audrey; Droit, Arnaud; Andrulis, Irene L; Anton-Culver, Hoda; Arndt, Volker; Baynes, Caroline; Blomqvist, Carl; Bogdanova, Natalia V; Bojesen, Stig E; Bolla, Manjeet K; Bonanni, Bernardo; Borresen-Dale, Anne-Lise; Brand, Judith S; Brauch, Hiltrud; Brenner, Hermann; Broeks, Annegien; Burwinkel, Barbara; Chang-Claude, Jenny; Couch, Fergus J; Cox, Angela; Cross, Simon S; Czene, Kamila; Darabi, Hatef; Dennis, Joe; Devilee, Peter; Dörk, Thilo; Dos-Santos-Silva, Isabel; Eriksson, Mikael; Fasching, Peter A; Figueroa, Jonine; Flyger, Henrik; García-Closas, Montserrat; Giles, Graham G; Goldberg, Mark S; González-Neira, Anna; Grenaker-Alnæs, Grethe; Guénel, Pascal; Haeberle, Lothar; Haiman, Christopher A; Hamann, Ute; Hallberg, Emily; Hooning, Maartje J; Hopper, John L; Jakubowska, Anna; Jones, Michael; Kabisch, Maria; Kataja, Vesa; Lambrechts, Diether; Le Marchand, Loic; Lindblom, Annika; Lubinski, Jan; Mannermaa, Arto; Maranian, Mel; Margolin, Sara; Marme, Frederik; Milne, Roger L; Neuhausen, Susan L; Nevanlinna, Heli; Neven, Patrick; Olswold, Curtis; Peto, Julian; Plaseska-Karanfilska, Dijana; Pylkäs, Katri; Radice, Paolo; Rudolph, Anja; Sawyer, Elinor J; Schmidt, Marjanka K; Shu, Xiao-Ou; Southey, Melissa C; Swerdlow, Anthony; Tollenaar, Rob A E M; Tomlinson, Ian; Torres, Diana; Truong, Thérèse; Vachon, Celine; Van Den Ouweland, Ans M W; Wang, Qin; Winqvist, Robert; Zheng, Wei; Benitez, Javier; Chenevix-Trench, Georgia; Dunning, Alison M; Pharoah, Paul D P; Kristensen, Vessela; Hall, Per; Easton, Douglas F; Pastinen, Tomi; Nord, Silje; Simard, Jacques

2016-12-06

There are significant inter-individual differences in the levels of gene expression. Through modulation of gene expression, cis-acting variants represent an important source of phenotypic variation. Consequently, cis-regulatory SNPs associated with differential allelic expression are functional candidates for further investigation as disease-causing variants. To investigate whether common variants associated with differential allelic expression were involved in breast cancer susceptibility, a list of genes was established on the basis of their involvement in cancer related pathways and/or mechanisms. Thereafter, using data from a genome-wide map of allelic expression associated SNPs, 313 genetic variants were selected and their association with breast cancer risk was then evaluated in 46,451 breast cancer cases and 42,599 controls of European ancestry ascertained from 41 studies participating in the Breast Cancer Association Consortium. The associations were evaluated with overall breast cancer risk and with estrogen receptor negative and positive disease. One novel breast cancer susceptibility locus on 4q21 (rs11099601) was identified (OR = 1.05, P = 5.6x10-6). rs11099601 lies in a 135 kb linkage disequilibrium block containing several genes, including, HELQ, encoding the protein HEL308 a DNA dependant ATPase and DNA Helicase involved in DNA repair, MRPS18C encoding the Mitochondrial Ribosomal Protein S18C and FAM175A (ABRAXAS), encoding a BRCA1 BRCT domain-interacting protein involved in DNA damage response and double-strand break (DSB) repair. Expression QTL analysis in breast cancer tissue showed rs11099601 to be associated with HELQ (P = 8.28x10-14), MRPS18C (P = 1.94x10-27) and FAM175A (P = 3.83x10-3), explaining about 20%, 14% and 1%, respectively of the variance inexpression of these genes in breast carcinomas.

Influence of cytochrome 2C19 allelic variants on on-treatment platelet reactivity evaluated by five different platelet function tests.

Science.gov (United States)

Gremmel, Thomas; Kopp, Christoph W; Moertl, Deddo; Seidinger, Daniela; Koppensteiner, Renate; Panzer, Simon; Mannhalter, Christine; Steiner, Sabine

2012-05-01

The antiplatelet effect of clopidogrel has been linked to cytochrome P450 2C19 (CYP2C19) carrier status. The presence of loss of function and gain of function variants were found to have a gene-dose effect on clopidogrel metabolism. However, genotyping is only one aspect of predicting response to clopidogrel and several platelet function tests are available to measure platelet response. Patients and methods We studied the influence of CYP2C19 allelic variants on on-treatment platelet reactivity as assessed by light transmission aggregometry (LTA), the VerifyNow P2Y12 assay, the VASP assay, multiple electrode aggregometry (MEA), and the Impact-R in 288 patients after stenting for cardiovascular disease. Allelic variants of CYP2C19 were determined with the Infiniti® CYP450 2C19+ assay and categorized into four metabolizer states (ultrarapid, extensive, intermediate, poor). Platelet reactivity increased linearly from ultrarapid to poor metabolizers using the VerifyNow P2Y12 assay (P = 0.04), the VASP assay (P = 0.02) and the Impact-R (P = 0.04). The proportion of patients with high on-treatment residual platelet reactivity (HRPR) identified by LTA, the VerifyNow P2Y12 assay and the VASP assay increased when the metabolizer status decreased, while no such relationship could be identified for results of MEA and Impact-R. The presence of loss of function variants (*2/*2, *2-8*/wt, *2/*17) was an independent predictor of HRPR in LTA and the VASP assay while it did not reach statistical significance in the VerifyNow P2Y12 assay, MEA, and the Impact-R. Depending on the type of platelet function test differences in the association of on-treatment platelet reactivity with CYP2C19 carrier status are observed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Influence of APOE and RNF219 on Behavioral and Cognitive Features of Female Patients Affected by Mild Cognitive Impairment or Alzheimer’s Disease

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Alessandra Mosca

2018-04-01

Full Text Available The risk for Alzheimer’s disease (AD is associated with the presence of the 4 allele of Apolipoprotein E (APOE gene and, recently, with a novel genetic variant of the RNF219 gene. This study aimed at evaluating interactions between APOE-4 and RNF219/G variants in the modulation of behavioral and cognitive features of two cohorts of patients suffering from mild cognitive impairment (MCI or AD. We enrolled a total of 173 female MCI or AD patients (83 MCI; 90 AD. Subjects were screened with a comprehensive set of neuropsychological evaluations and genotyped for the APOE and RNF219 polymorphic variants. Analysis of covariance was performed to assess the main and interaction effects of APOE and RNF219 genotypes on the cognitive and behavioral scores. The analysis revealed that the simultaneous presence of APOE-4 and RNF219/G variants results in significant effects on specific neuropsychiatric scores in MCI and AD patients. In MCI patients, RNF219 and APOE variants worked together to impact the levels of anxiety negatively. Similarly, in AD patients, the RNF219 variants were found to be associated with increased anxiety levels. Our data indicate a novel synergistic activity APOE and RNF219 in the modulation of behavioral traits of female MCI and AD patients.

Complex analysis of urate transporters SLC2A9, SLC22A12 and functional characterization of non-synonymous allelic variants of GLUT9 in the Czech population: no evidence of effect on hyperuricemia and gout.

Directory of Open Access Journals (Sweden)

Olha Hurba

Full Text Available OBJECTIVE: Using European descent Czech populations, we performed a study of SLC2A9 and SLC22A12 genes previously identified as being associated with serum uric acid concentrations and gout. This is the first study of the impact of non-synonymous allelic variants on the function of GLUT9 except for patients suffering from renal hypouricemia type 2. METHODS: The cohort consisted of 250 individuals (150 controls, 54 nonspecific hyperuricemics and 46 primary gout and/or hyperuricemia subjects. We analyzed 13 exons of SLC2A9 (GLUT9 variant 1 and GLUT9 variant 2 and 10 exons of SLC22A12 by PCR amplification and sequenced directly. Allelic variants were prepared and their urate uptake and subcellular localization were studied by Xenopus oocytes expression system. The functional studies were analyzed using the non-parametric Wilcoxon and Kruskall-Wallis tests; the association study used the Fisher exact test and linear regression approach. RESULTS: We identified a total of 52 sequence variants (12 unpublished. Eight non-synonymous allelic variants were found only in SLC2A9: rs6820230, rs2276961, rs144196049, rs112404957, rs73225891, rs16890979, rs3733591 and rs2280205. None of these variants showed any significant difference in the expression of GLUT9 and in urate transport. In the association study, eight variants showed a possible association with hyperuricemia. However, seven of these were in introns and the one exon located variant, rs7932775, did not show a statistically significant association with serum uric acid concentration. CONCLUSION: Our results did not confirm any effect of SLC22A12 and SLC2A9 variants on serum uric acid concentration. Our complex approach using association analysis together with functional and immunohistochemical characterization of non-synonymous allelic variants did not show any influence on expression, subcellular localization and urate uptake of GLUT9.

Allelic variant in the anti-Müllerian hormone gene leads to autosomal and temperature-dependent sex reversal in a selected Nile tilapia line.

Directory of Open Access Journals (Sweden)

Stephan Wessels

Full Text Available Owing to the demand for sustainable sex-control protocols in aquaculture, research in tilapia sex determination is gaining momentum. The mutual influence of environmental and genetic factors hampers disentangling the complex sex determination mechanism in Nile tilapia (Oreochromis niloticus. Previous linkage analyses have demonstrated quantitative trait loci for the phenotypic sex on linkage groups 1, 3, and 23. Quantitative trait loci for temperature-dependent sex reversal similarly reside on linkage group 23. The anti-Müllerian hormone gene (amh, located in this genomic region, is important for sexual fate in higher vertebrates, and shows sexually dimorphic expression in Nile tilapia. Therefore this study aimed at detecting allelic variants and marker-sex associations in the amh gene. Sequencing identified six allelic variants. A significant effect on the phenotypic sex for SNP ss831884014 (p<0.0017 was found by stepwise logistic regression. The remaining variants were not significantly associated. Functional annotation of SNP ss831884014 revealed a non-synonymous amino acid substitution in the amh protein. Consequently, a fluorescence resonance energy transfer (FRET based genotyping assay was developed and validated with a representative sample of fish. A logistic linear model confirmed a highly significant effect of the treatment and genotype on the phenotypic sex, but not for the interaction term (treatment: p<0.0001; genotype: p<0.0025. An additive genetic model proved a linear allele substitution effect of 12% in individuals from controls and groups treated at high temperature, respectively. Moreover, the effect of the genotype on the male proportion was significantly higher in groups treated at high temperature, giving 31% more males on average of the three genotypes. In addition, the groups treated at high temperature showed a positive dominance deviation (+11.4% males. In summary, marker-assisted selection for amh variant ss831884014

Preferential Allele Expression Analysis Identifies Shared Germline and Somatic Driver Genes in Advanced Ovarian Cancer

Science.gov (United States)

Halabi, Najeeb M.; Martinez, Alejandra; Al-Farsi, Halema; Mery, Eliane; Puydenus, Laurence; Pujol, Pascal; Khalak, Hanif G.; McLurcan, Cameron; Ferron, Gwenael; Querleu, Denis; Al-Azwani, Iman; Al-Dous, Eman; Mohamoud, Yasmin A.; Malek, Joel A.; Rafii, Arash

2016-01-01

Identifying genes where a variant allele is preferentially expressed in tumors could lead to a better understanding of cancer biology and optimization of targeted therapy. However, tumor sample heterogeneity complicates standard approaches for detecting preferential allele expression. We therefore developed a novel approach combining genome and transcriptome sequencing data from the same sample that corrects for sample heterogeneity and identifies significant preferentially expressed alleles. We applied this analysis to epithelial ovarian cancer samples consisting of matched primary ovary and peritoneum and lymph node metastasis. We find that preferentially expressed variant alleles include germline and somatic variants, are shared at a relatively high frequency between patients, and are in gene networks known to be involved in cancer processes. Analysis at a patient level identifies patient-specific preferentially expressed alleles in genes that are targets for known drugs. Analysis at a site level identifies patterns of site specific preferential allele expression with similar pathways being impacted in the primary and metastasis sites. We conclude that genes with preferentially expressed variant alleles can act as cancer drivers and that targeting those genes could lead to new therapeutic strategies. PMID:26735499

The human pregnane X receptor: genomic structure and identification and functional characterization of natural allelic variants.

Science.gov (United States)

Zhang, J; Kuehl, P; Green, E D; Touchman, J W; Watkins, P B; Daly, A; Hall, S D; Maurel, P; Relling, M; Brimer, C; Yasuda, K; Wrighton, S A; Hancock, M; Kim, R B; Strom, S; Thummel, K; Russell, C G; Hudson, J R; Schuetz, E G; Boguski, M S

2001-10-01

The pregnane X receptor (PXR)/steroid and xenobiotic receptor (SXR) transcriptionally activates cytochrome P4503A4 (CYP3A4) when ligand activated by endobiotics and xenobiotics. We cloned the human PXR gene and analysed the sequence in DNAs of individuals whose CYP3A phenotype was known. The PXR gene spans 35 kb, contains nine exons, and mapped to chromosome 13q11-13. Thirty-eight single nucleotide polymorphisms (SNPs) were identified including six SNPs in the coding region. Three of the coding SNPs are non-synonymous creating new PXR alleles [PXR*2, P27S (79C to T); PXR*3, G36R (106G to A); and PXR*4, R122Q (4321G to A)]. The frequency of PXR*2 was 0.20 in African Americans and was never found in Caucasians. Hepatic expression of CYP3A4 protein was not significantly different between African Americans homozygous for PXR*1 compared to those with one PXR*2 allele. PXR*4 was a rare variant found in only one Caucasian person. Homology modelling suggested that R122Q, (PXR*4) is a direct DNA contact site variation in the third alpha-helix in the DNA binding domain. Compared with PXR*1, and variants PXR*2 and PXR*3, only the variant PXR*4 protein had significantly decreased affinity for the PXR binding sequence in electromobility shift assays and attenuated ligand activation of the CYP3A4 reporter plasmids in transient transfection assays. However, the person heterozygous for PXR*4 is normal for CYP3A4 metabolism phenotype. The relevance of each of the 38 PXR SNPs identified in DNA of individuals whose CYP3A basal and rifampin-inducible CYP3A4 expression was determined in vivo and/or in vitro was demonstrated by univariate statistical analysis. Because ligand activation of PXR and upregulation of a system of drug detoxification genes are major determinants of drug interactions, it will now be useful to extend this work to determine the association of these common PXR SNPs to human variation in induction of other drug detoxification gene targets.

Vaccine Containing the Three Allelic Variants of the Plasmodium vivax Circumsporozoite Antigen Induces Protection in Mice after Challenge with a Transgenic Rodent Malaria Parasite

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Alba Marina Gimenez

2017-10-01

Full Text Available Plasmodium vivax is the most common species that cause malaria outside of the African continent. The development of an efficacious vaccine would contribute greatly to control malaria. Recently, using bacterial and adenoviral recombinant proteins based on the P. vivax circumsporozoite protein (CSP, we demonstrated the possibility of eliciting strong antibody-mediated immune responses to each of the three allelic forms of P. vivax CSP (PvCSP. In the present study, recombinant proteins representing the PvCSP alleles (VK210, VK247, and P. vivax-like, as well as a hybrid polypeptide, named PvCSP-All epitopes, were generated. This hybrid containing the conserved C-terminal of the PvCSP and the three variant repeat domains in tandem were successfully produced in the yeast Pichia pastoris. After purification and biochemical characterization, they were used for the experimental immunization of C57BL/6 mice in a vaccine formulation containing the adjuvant Poly(I:C. Immunization with a recombinant protein expressing all three different allelic forms in fusion elicited high IgG antibody titers reacting with all three different allelic variants of PvCSP. The antibodies targeted both the C-terminal and repeat domains of PvCSP and recognized the native protein on the surface of P. vivax sporozoites. More importantly, mice that received the vaccine formulation were protected after challenge with chimeric Plasmodium berghei sporozoites expressing CSP repeats of P. vivax sporozoites (Pb/PvVK210. Our results suggest that it is possible to elicit protective immunity against one of the most common PvCSP alleles using soluble recombinant proteins expressed by P. pastoris. These recombinant proteins are promising candidates for clinical trials aiming to develop a multiallele vaccine against P. vivax malaria.

Determination of allele frequencies in nine short tandem repeat loci ...

African Journals Online (AJOL)

SERVER

2008-04-17

Apr 17, 2008 ... the normal cellular process of replication of DNA molecules. ... probability of a certain genetic variant (alleles) occuring in ... have preservatives that hinder spoilage and are easily packaged .... Allele distribution at Nine STR.

Efficacy of DNA double-strand breaks repair in breast cancer is decreased in carriers of the variant allele of the UBC9 gene c.73G>A polymorphism

International Nuclear Information System (INIS)

Synowiec, Ewelina; Krupa, Renata; Morawiec, Zbigniew; Wasylecka, Maja; Dziki, Lukasz; Morawiec, Jan; Blasiak, Janusz; Wozniak, Katarzyna

2010-01-01

UBC9 (E2) SUMO conjugating enzyme plays an important role in the maintenance of genome stability and integrity. In the present work we examined the association between the c.73G>A (Val25Met) polymorphism of the UBC9 gene (rs11553473) and efficacy of DNA double-strand breaks (DSBs) repair (DRE) in breast cancer patients. We determined the level of endogenous (basal) and exogenous (induced by γ-irradiation) DSBs and efficacy of their repair in peripheral blood lymphocytes of 57 breast cancer patients and 70 healthy individuals. DNA damage and repair were studied by neutral comet assay. Genotypes were determined in DNA from peripheral blood lymphocytes by allele-specific PCR (ASO-PCR). We also correlated genotypes with the clinical characteristics of breast cancer patients. We observed a strong association between breast cancer occurrence and the variant allele carried genotypes in patients with elevated level of basal as well as induced DNA damage (OR 6.74, 95% CI 2.27-20.0 and OR 5.33, 95% CI 1.81-15.7, respectively). We also found statistically significant (p A polymorphism of the UBC9 gene in breast cancer patients. Carriers of variant allele have decreased DNA DRE as compared to wild type genotype carriers. We did not find any association with the UBC9 gene polymorphism and estrogen and progesterone receptor status. The variant allele of the UBC9 gene polymorphism was strongly inversely related to HER negative breast cancer patients (OR 0.03, 95% CI 0.00-0.23). Our results suggest that the c.73G>A polymorphism of the UBC9 gene may affect DNA DSBs repair efficacy in breast cancer patients.

A detailed clinical and molecular survey of subjects with nonsyndromic USH2A retinopathy reveals an allelic hierarchy of disease-causing variants

Science.gov (United States)

Lenassi, Eva; Vincent, Ajoy; Li, Zheng; Saihan, Zubin; Coffey, Alison J; Steele-Stallard, Heather B; Moore, Anthony T; Steel, Karen P; Luxon, Linda M; Héon, Elise; Bitner-Glindzicz, Maria; Webster, Andrew R

2015-01-01

Defects in USH2A cause both isolated retinal disease and Usher syndrome (ie, retinal disease and deafness). To gain insights into isolated/nonsyndromic USH2A retinopathy, we screened USH2A in 186 probands with recessive retinal disease and no hearing complaint in childhood (discovery cohort) and in 84 probands with recessive retinal disease (replication cohort). Detailed phenotyping, including retinal imaging and audiological assessment, was performed in individuals with two likely disease-causing USH2A variants. Further genetic testing, including screening for a deep-intronic disease-causing variant and large deletions/duplications, was performed in those with one likely disease-causing change. Overall, 23 of 186 probands (discovery cohort) were found to harbour two likely disease-causing variants in USH2A. Some of these variants were predominantly associated with nonsyndromic retinal degeneration (‘retinal disease-specific'); these included the common c.2276 G>T, p.(Cys759Phe) mutation and five additional variants: c.2802 T>G, p.(Cys934Trp); c.10073 G>A, p.(Cys3358Tyr); c.11156 G>A, p.(Arg3719His); c.12295-3 T>A; and c.12575 G>A, p.(Arg4192His). An allelic hierarchy was observed in the discovery cohort and confirmed in the replication cohort. In nonsyndromic USH2A disease, retinopathy was consistent with retinitis pigmentosa and the audiological phenotype was variable. USH2A retinopathy is a common cause of nonsyndromic recessive retinal degeneration and has a different mutational spectrum to that observed in Usher syndrome. The following model is proposed: the presence of at least one ‘retinal disease-specific' USH2A allele in a patient with USH2A-related disease results in the preservation of normal hearing. Careful genotype–phenotype studies such as this will become increasingly important, especially now that high-throughput sequencing is widely used in the clinical setting. PMID:25649381

Electrophoretic variants of blood proteins in japanese, 5

International Nuclear Information System (INIS)

Fujita, Mikio; Satoh, Chiyoko; Asakawa, Jun-ichi; Nagahata, Yuko; Tanaka, Yoshiko; Hazama, Ryuji; Goriki, Kazuaki.

1985-08-01

The plasma ceruloplasmin (CP) of 22,367 children of atomic bomb survivors in Hiroshima and Nagasaki was examined for variants by electrophoresis. The sample was composed of 14,964 unrelated children and 7,403 siblings of the unrelated persons. A total of seven types of electrophoretic variants were detected; four migrating anodally and three cathodally to the normal B band. We have reported two of these variants, CP A sub(NG1) and CP C sub(NG1), previously but the other five, CP A sub(NG2), CP A sub(HR1), CP A sub(HR2), CP C sub(HR1), and CP C sub(HR2), are newly identified. The allelic frequency of CP*CNG1 was 0.00916, so that the variant is considered to be a polymorphic allele. Homozygosity for the CP*CNG1 allele was detected in five individuals. This is the first report of a homozygous phenotype for a CP variant in a Japanese population. Family study of the new five variants all demonstrated patterns of codominant inheritance. (author)

Mutation intolerant genes and targets of FMRP are enriched for nonsynonymous alleles in schizophrenia.

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Leonenko, Ganna; Richards, Alexander L; Walters, James T; Pocklington, Andrew; Chambert, Kimberly; Al Eissa, Mariam M; Sharp, Sally I; O'Brien, Niamh L; Curtis, David; Bass, Nicholas J; McQuillin, Andrew; Hultman, Christina; Moran, Jennifer L; McCarroll, Steven A; Sklar, Pamela; Neale, Benjamin M; Holmans, Peter A; Owen, Michael J; Sullivan, Patrick F; O'Donovan, Michael C

2017-10-01

Risk of schizophrenia is conferred by alleles occurring across the full spectrum of frequencies from common SNPs of weak effect through to ultra rare alleles, some of which may be moderately to highly penetrant. Previous studies have suggested that some of the risk of schizophrenia is attributable to uncommon alleles represented on Illumina exome arrays. Here, we present the largest study of exomic variation in schizophrenia to date, using samples from the United Kingdom and Sweden (10,011 schizophrenia cases and 13,791 controls). Single variants, genes, and gene sets were analyzed for association with schizophrenia. No single variant or gene reached genome-wide significance. Among candidate gene sets, we found significant enrichment for rare alleles (minor allele frequency [MAF] schizophrenia by excluding a role for uncommon exomic variants (0.01 ≤ MAF ≥ 0.001) that confer a relatively large effect (odds ratio [OR] > 4). We also show risk alleles within this frequency range exist, but confer smaller effects and should be identified by larger studies. © 2017 Wiley Periodicals, Inc.

Advantage of using allele-specific copy numbers when testing for association in regions with common copy number variants.

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Gaëlle Marenne

Full Text Available Copy number variants (CNV can be called from SNP-arrays; however, few studies have attempted to combine both CNV and SNP calls to test for association with complex diseases. Even when SNPs are located within CNVs, two separate association analyses are necessary, to compare the distribution of bi-allelic genotypes in cases and controls (referred to as SNP-only strategy and the number of copies of a region (referred to as CNV-only strategy. However, when disease susceptibility is actually associated with allele specific copy-number states, the two strategies may not yield comparable results, raising a series of questions about the optimal analytical approach. We performed simulations of the performance of association testing under different scenarios that varied genotype frequencies and inheritance models. We show that the SNP-only strategy lacks power under most scenarios when the SNP is located within a CNV; frequently it is excluded from analysis as it does not pass quality control metrics either because of an increased rate of missing calls or a departure from fitness for Hardy-Weinberg proportion. The CNV-only strategy also lacks power because the association testing depends on the allele which copy number varies. The combined strategy performs well in most of the scenarios. Hence, we advocate the use of this combined strategy when testing for association with SNPs located within CNVs.

Fine-mapping the HOXB region detects common variants tagging a rare coding allele: evidence for synthetic association in prostate cancer.

Directory of Open Access Journals (Sweden)

Edward J Saunders

2014-02-01

Full Text Available The HOXB13 gene has been implicated in prostate cancer (PrCa susceptibility. We performed a high resolution fine-mapping analysis to comprehensively evaluate the association between common genetic variation across the HOXB genetic locus at 17q21 and PrCa risk. This involved genotyping 700 SNPs using a custom Illumina iSelect array (iCOGS followed by imputation of 3195 SNPs in 20,440 PrCa cases and 21,469 controls in The PRACTICAL consortium. We identified a cluster of highly correlated common variants situated within or closely upstream of HOXB13 that were significantly associated with PrCa risk, described by rs117576373 (OR 1.30, P = 2.62×10(-14. Additional genotyping, conditional regression and haplotype analyses indicated that the newly identified common variants tag a rare, partially correlated coding variant in the HOXB13 gene (G84E, rs138213197, which has been identified recently as a moderate penetrance PrCa susceptibility allele. The potential for GWAS associations detected through common SNPs to be driven by rare causal variants with higher relative risks has long been proposed; however, to our knowledge this is the first experimental evidence for this phenomenon of synthetic association contributing to cancer susceptibility.

Allele variants of HLA II genes DRB1 and DQB1 regarding risk for type 1 diabetes mellitus in population of Bashkortostan

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Shamilevna Avzaletdinova

2012-09-01

Full Text Available Aims. To estimate significance of HLA II DRB1 and DRB2 allele variants for development of type 1 diabetes mellitus (T1DM in Bashkortostanpopulation (ethnical Russians, Tatar, Bashkir. Materials and methods. We analyzed DNA of 323 patients with T1DM and 683 healthy controls. DNA was derived from venous bloodsamples by phenol-chloroform extraction. DRB1 and DQB1 gene typing was performed by PCR method. Amplification products wereidentified with electrophoresis on a 1% agarose gel. Statistica for Windows v6.0 and MS Excel 98 software were applied for statisticalprocessing of acquired data. Results. Common markers of high risk for T1DM were found to be DRB1*04, DRB1*17, genotype DRB1*04/*17. On the contrary,lower risk was associated with DRB1*15 allele. In ethnical Russians lower risk of T1DM is also determined by DRB1*11 allele andDRB1*01 in Tatars. Predisposition by DQB1-alleles in Russians and Bashkir realizes only within DRB1*04/*17 genotype. However,in Tatar subpopulation DQB1*0302 is an independent risk marker of T1DM development. Conclusion. Common low risk markers for all three ethnic groups are DQB1*0301, DQB1*0602-08 alleles. Their presence negates riskof disease in all studied subpopulations even within DRB1*04/*17-genotype.

Efficacy of DNA double-strand breaks repair in breast cancer is decreased in carriers of the variant allele of the UBC9 gene c.73G>A polymorphism

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Synowiec, Ewelina [Department of Molecular Genetics, University of Lodz, Lodz (Poland); Krupa, Renata [Laboratory of DNA Repair, Department of Molecular Genetics, University of Lodz, Banacha 12/16, Lodz (Poland); Morawiec, Zbigniew; Wasylecka, Maja [Department of Surgical Oncology, N. Copernicus Hospital, Lodz (Poland); Dziki, Lukasz; Morawiec, Jan [Department of General and Colorectal Surgery, Medical University of Lodz, Lodz (Poland); Blasiak, Janusz [Department of Molecular Genetics, University of Lodz, Lodz (Poland); Wozniak, Katarzyna, E-mail: wozniak@biol.uni.lodz.pl [Laboratory of DNA Repair, Department of Molecular Genetics, University of Lodz, Banacha 12/16, Lodz (Poland)

2010-12-10

UBC9 (E2) SUMO conjugating enzyme plays an important role in the maintenance of genome stability and integrity. In the present work we examined the association between the c.73G>A (Val25Met) polymorphism of the UBC9 gene (rs11553473) and efficacy of DNA double-strand breaks (DSBs) repair (DRE) in breast cancer patients. We determined the level of endogenous (basal) and exogenous (induced by {gamma}-irradiation) DSBs and efficacy of their repair in peripheral blood lymphocytes of 57 breast cancer patients and 70 healthy individuals. DNA damage and repair were studied by neutral comet assay. Genotypes were determined in DNA from peripheral blood lymphocytes by allele-specific PCR (ASO-PCR). We also correlated genotypes with the clinical characteristics of breast cancer patients. We observed a strong association between breast cancer occurrence and the variant allele carried genotypes in patients with elevated level of basal as well as induced DNA damage (OR 6.74, 95% CI 2.27-20.0 and OR 5.33, 95% CI 1.81-15.7, respectively). We also found statistically significant (p < 0.05) difference in DRE related to the c.73G>A polymorphism of the UBC9 gene in breast cancer patients. Carriers of variant allele have decreased DNA DRE as compared to wild type genotype carriers. We did not find any association with the UBC9 gene polymorphism and estrogen and progesterone receptor status. The variant allele of the UBC9 gene polymorphism was strongly inversely related to HER negative breast cancer patients (OR 0.03, 95% CI 0.00-0.23). Our results suggest that the c.73G>A polymorphism of the UBC9 gene may affect DNA DSBs repair efficacy in breast cancer patients.

QuASAR-MPRA: accurate allele-specific analysis for massively parallel reporter assays.

Science.gov (United States)

Kalita, Cynthia A; Moyerbrailean, Gregory A; Brown, Christopher; Wen, Xiaoquan; Luca, Francesca; Pique-Regi, Roger

2018-03-01

The majority of the human genome is composed of non-coding regions containing regulatory elements such as enhancers, which are crucial for controlling gene expression. Many variants associated with complex traits are in these regions, and may disrupt gene regulatory sequences. Consequently, it is important to not only identify true enhancers but also to test if a variant within an enhancer affects gene regulation. Recently, allele-specific analysis in high-throughput reporter assays, such as massively parallel reporter assays (MPRAs), have been used to functionally validate non-coding variants. However, we are still missing high-quality and robust data analysis tools for these datasets. We have further developed our method for allele-specific analysis QuASAR (quantitative allele-specific analysis of reads) to analyze allele-specific signals in barcoded read counts data from MPRA. Using this approach, we can take into account the uncertainty on the original plasmid proportions, over-dispersion, and sequencing errors. The provided allelic skew estimate and its standard error also simplifies meta-analysis of replicate experiments. Additionally, we show that a beta-binomial distribution better models the variability present in the allelic imbalance of these synthetic reporters and results in a test that is statistically well calibrated under the null. Applying this approach to the MPRA data, we found 602 SNPs with significant (false discovery rate 10%) allele-specific regulatory function in LCLs. We also show that we can combine MPRA with QuASAR estimates to validate existing experimental and computational annotations of regulatory variants. Our study shows that with appropriate data analysis tools, we can improve the power to detect allelic effects in high-throughput reporter assays. http://github.com/piquelab/QuASAR/tree/master/mpra. fluca@wayne.edu or rpique@wayne.edu. Supplementary data are available online at Bioinformatics. © The Author (2017). Published by

Impaired cognitive flexibility during sleep deprivation among carriers of the Brain Derived Neurotrophic Factor (BDNF) Val66Met allele.

Science.gov (United States)

Grant, Leilah K; Cain, Sean W; Chang, Anne-Marie; Saxena, Richa; Czeisler, Charles A; Anderson, Clare

2018-02-15

Accumulating evidence points to a genetic contribution to explain inter-individual vulnerability to sleep deprivation. A functional polymorphism in the BDNF gene, which causes a valine (Val) to methionine (Met) amino acid substitution at Codon 66, has been associated with cognitive impairment, particularly in populations with impaired frontal functioning. We hypothesised that sleep deprivation, which affects frontal function, may lead to cognitive dysfunction in Met allele carriers. To examine this, we investigated, in different BDNF genotypes, the effects of sleep deprivation on cognitive flexibility, as measured by response inhibition using the Stroop Color Naming Task. Thirty healthy, adults of European ancestry, including 12 heterozygous Met allele carriers and 18 Val/Val homozygotes, underwent 30-h of extended wakefulness under constant routine conditions. A computerised Stroop task was administered every 2h. Error rate and reaction times increased with time awake for all individuals. Participants with the Val/Met genotype made more errors on incongruent trials after 20h awake. While Val/Met participants also took significantly longer to respond when inhibiting a prepotent response irrespective of time awake, this was particularly evident during the biological night. Our study shows that carriers of the BDNF Met allele are more vulnerable to the impact of prolonged wakefulness and the biological night on a critical component of executive function, as measured by response inhibition on the Stroop task. Copyright © 2017 Elsevier B.V. All rights reserved.

Stress-related methylation of the catechol-O-methyltransferase Val 158 allele predicts human prefrontal cognition and activity.

Science.gov (United States)

Ursini, Gianluca; Bollati, Valentina; Fazio, Leonardo; Porcelli, Annamaria; Iacovelli, Luisa; Catalani, Assia; Sinibaldi, Lorenzo; Gelao, Barbara; Romano, Raffaella; Rampino, Antonio; Taurisano, Paolo; Mancini, Marina; Di Giorgio, Annabella; Popolizio, Teresa; Baccarelli, Andrea; De Blasi, Antonio; Blasi, Giuseppe; Bertolino, Alessandro

2011-05-04

DNA methylation at CpG dinucleotides is associated with gene silencing, stress, and memory. The catechol-O-methyltransferase (COMT) Val(158) allele in rs4680 is associated with differential enzyme activity, stress responsivity, and prefrontal activity during working memory (WM), and it creates a CpG dinucleotide. We report that methylation of the Val(158) allele measured from peripheral blood mononuclear cells (PBMCs) of Val/Val humans is associated negatively with lifetime stress and positively with WM performance; it interacts with stress to modulate prefrontal activity during WM, such that greater stress and lower methylation are related to reduced cortical efficiency; and it is inversely related to mRNA expression and protein levels, potentially explaining the in vivo effects. Finally, methylation of COMT in prefrontal cortex and that in PBMCs of rats are correlated. The relationship of methylation of the COMT Val(158) allele with stress, gene expression, WM performance, and related brain activity suggests that stress-related methylation is associated with silencing of the gene, which partially compensates the physiological role of the high-activity Val allele in prefrontal cognition and activity. Moreover, these results demonstrate how stress-related DNA methylation of specific functional alleles impacts directly on human brain physiology beyond sequence variation.

Widespread signatures of positive selection in common risk alleles associated to autism spectrum disorder.

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Renato Polimanti

2017-02-01

Full Text Available The human brain is the outcome of innumerable evolutionary processes; the systems genetics of psychiatric disorders could bear their signatures. On this basis, we analyzed five psychiatric disorders, attention deficit hyperactivity disorder, autism spectrum disorder (ASD, bipolar disorder, major depressive disorder, and schizophrenia (SCZ, using GWAS summary statistics from the Psychiatric Genomics Consortium. Machine learning-derived scores were used to investigate two natural-selection scenarios: complete selection (loci where a selected allele reached fixation and incomplete selection (loci where a selected allele has not yet reached fixation. ASD GWAS results positively correlated with incomplete-selection (p = 3.53*10-4. Variants with ASD GWAS p<0.1 were shown to have a 19%-increased probability to be in the top-5% for incomplete-selection score (OR = 1.19, 95%CI = 1.11-1.8, p = 9.56*10-7. Investigating the effect directions of minor alleles, we observed an enrichment for positive associations in SNPs with ASD GWAS p<0.1 and top-5% incomplete-selection score (permutation p<10-4. Considering the set of these ASD-positive-associated variants, we observed gene-expression enrichments for brain and pituitary tissues (p = 2.3*10-5 and p = 3*10-5, respectively and 53 gene ontology (GO enrichments, such as nervous system development (GO:0007399, p = 7.57*10-12, synapse organization (GO:0050808, p = 8.29*10-7, and axon guidance (GO:0007411, p = 1.81*10-7. Previous genetic studies demonstrated that ASD positively correlates with childhood intelligence, college completion, and years of schooling. Accordingly, we hypothesize that certain ASD risk alleles were under positive selection during human evolution due to their involvement in neurogenesis and cognitive ability.

Deleterious alleles in the human genome are on average younger than neutral alleles of the same frequency

NARCIS (Netherlands)

Kiezun, Adam; Pulit, Sara L.; Francioli, Laurent C.; van Dijk, Freerk; Swertz, Morris; Boomsma, Dorret I.; van Duijn, Cornelia M.; Slagboom, P. Eline; van Ommen, G. J. B.; Wijmenga, Cisca; de Bakker, Paul I. W.; Sunyaev, Shamil R.

Large-scale population sequencing studies provide a complete picture of human genetic variation within the studied populations. A key challenge is to identify, among the myriad alleles, those variants that have an effect on molecular function, phenotypes, and reproductive fitness. Most non-neutral

Neuropsychological effects of the CSMD1 genome-wide associated schizophrenia risk variant rs10503253.

LENUS (Irish Health Repository)

Donohoe, G

2013-03-01

The single-nucleotide polymorphism (SNP) rs10503253, located within the CUB and Sushi multiple domains-1 (CSMD1) gene on 8p23.2, was recently identified as genome-wide significant for schizophrenia (SZ), but is of unknown function. We investigated the neurocognitive effects of this CSMD1 variant in vivo in patients and healthy participants using behavioral and imaging measures of brain structure and function. We compared carriers and non-carriers of the risk \\'A\\' allele on measures of neuropsychological performance typically impaired in SZ (general cognitive ability, episodic and working memory and attentional control) in independent samples of Irish patients (n = 387) and controls (n = 171) and German patients (205) and controls (n = 533). Across these groups, the risk \\'A\\' allele at CSMD1 was associated with deleterious effects across a number of neurocognitive phenotypes. Specifically, the risk allele was associated with poorer performance on neuropsychological measures of general cognitive ability and memory function but not attentional control. These effects, while significant, were subtle, and varied between samples. Consistent with previous evidence suggesting that CSMD1 may be involved in brain mechanisms related to memory and learning, these data appear to reflect the deleterious effects of the identified \\'A\\' risk allele on neurocognitive function, possibly as part of the mechanism by which CSMD1 is associated with SZ risk.

ZNF804A variants confer risk for heroin addiction and affect decision making and gray matter volume in heroin abusers.

Science.gov (United States)

Sun, Yan; Zhao, Li-Yan; Wang, Gui-Bin; Yue, Wei-Hua; He, Yong; Shu, Ni; Lin, Qi-Xiang; Wang, Fan; Li, Jia-Li; Chen, Na; Wang, Hui-Min; Kosten, Thomas R; Feng, Jia-Jia; Wang, Jun; Tang, Yu-De; Liu, Shu-Xue; Deng, Gui-Fa; Diao, Gan-Huan; Tan, Yun-Long; Han, Hong-Bin; Lin, Lu; Shi, Jie

2016-05-01

Drug addiction shares common neurobiological pathways and risk genes with other psychiatric diseases, including psychosis. One of the commonly identified risk genes associated with broad psychosis has been ZNF804A. We sought to test whether psychosis risk variants in ZNF804A increase the risk of heroin addiction by modulating neurocognitive performance and gray matter volume (GMV) in heroin addiction. Using case-control genetic analysis, we compared the distribution of ZNF804A variants (genotype and haplotype) in 1035 heroin abusers and 2887 healthy subjects. We also compared neurocognitive performance (impulsivity, global cognitive ability and decision-making ability) in 224 subjects and GMV in 154 subjects based on the ZNF804A variants. We found significant differences in the distribution of ZNF804A intronic variants (rs1344706 and rs7597593) allele and haplotype frequencies between the heroin and control groups. Decision-making impairment was worse in heroin abusers who carried the ZNF804A risk allele and haplotype. Subjects who carried more risk alleles and haplotypes of ZNF804A had greater GMV in the bilateral insular cortex, right temporal cortex and superior parietal cortex. The interaction between heroin addiction and ZNF804A variants affected GMV in the left sensorimotor cortex. Our findings revealed several ZNF804A variants that were significantly associated with the risk of heroin addiction, and these variants affected decision making and GMV in heroin abusers compared with controls. The precise neural mechanisms that underlie these associations are unknown, which requires future investigations of the effects of ZNF804A on both dopamine neurotransmission and the relative increases in the volume of various brain areas. © 2015 Society for the Study of Addiction.

Common genetic variants associated with cognitive performance identified using the proxy-phenotype method

NARCIS (Netherlands)

C.A. Rietveld (Niels); T. Esko (Tõnu); G. Davies (Gail); T.H. Pers (Tune); P. Turley (Patrick); B. Benyamin (Beben); C.F. Chabris (Christopher F.); V. Emilsson (Valur); A.D. Johnson (Andrew); J.J. Lee (James J.); C. de Leeuw (Christiaan); R.E. Marioni (Riccardo); S.E. Medland (Sarah Elizabeth); M. Miller (Mike); O. Rostapshova (Olga); S.J. van der Lee (Sven); A.A.E. Vinkhuyzen (Anna A.); N. Amin (Najaf); D. Conley (Dalton); J. Derringer; C.M. van Duijn (Cornelia); R.S.N. Fehrmann (Rudolf); L. Franke (Lude); E.L. Glaeser (Edward L.); N.K. Hansell (Narelle); C. Hayward (Caroline); W.G. Iacono (William); C.A. Ibrahim-Verbaas (Carla); V.W.V. Jaddoe (Vincent); J. Karjalainen (Juha); D. Laibson (David); P. Lichtenstein (Paul); D.C. Liewald (David C.); P.K. Magnusson (Patrik); N.G. Martin (Nicholas); M. McGue (Matt); G. Mcmahon (George); N.L. Pedersen (Nancy); S. Pinker (Steven); D.J. Porteous (David J.); D. Posthuma (Danielle); F. Rivadeneira Ramirez (Fernando); B.H. Smithk (Blair H.); J.M. Starr (John); H.W. Tiemeier (Henning); N.J. Timpsonm (Nicholas J.); M. Trzaskowskin (Maciej); A.G. Uitterlinden (André); F.C. Verhulst (Frank); M.E. Ward (Mary); M.J. Wright (Margaret); G.D. Smith; I.J. Deary (Ian J.); M. Johannesson (Magnus); R. Plomin (Robert); P.M. Visscher (Peter); D.J. Benjamin (Daniel J.); D. Cesarini (David); Ph.D. Koellinger (Philipp)

2014-01-01

textabstractWe identify common genetic variants associated with cognitive performance using a two-stage approach, which we call the proxyphenotype method. First, we conduct a genome-wide association study of educational attainment in a large sample (n = 106,736), which produces a set of 69

Assessment of Cognitive Function in Breast Cancer and Lymphoma Patients Receiving Chemotherapy | Division of Cancer Prevention

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Cognitive impairments in cancer patients represent an important clinical problem. Studies to date estimating prevalence of difficulties in memory, executive function, and attention deficits have been limited by small sample sizes and many have lacked healthy control groups. More information is needed on promising biomarkers and allelic variants that may help to determine the

Late-onset Alzheimer's risk variants in memory decline, incident mild cognitive impairment, and Alzheimer's disease.

Science.gov (United States)

Carrasquillo, Minerva M; Crook, Julia E; Pedraza, Otto; Thomas, Colleen S; Pankratz, V Shane; Allen, Mariet; Nguyen, Thuy; Malphrus, Kimberly G; Ma, Li; Bisceglio, Gina D; Roberts, Rosebud O; Lucas, John A; Smith, Glenn E; Ivnik, Robert J; Machulda, Mary M; Graff-Radford, Neill R; Petersen, Ronald C; Younkin, Steven G; Ertekin-Taner, Nilüfer

2015-01-01

We tested association of nine late-onset Alzheimer's disease (LOAD) risk variants from genome-wide association studies (GWAS) with memory and progression to mild cognitive impairment (MCI) or LOAD (MCI/LOAD) in older Caucasians, cognitively normal at baseline and longitudinally evaluated at Mayo Clinic Rochester and Jacksonville (n>2000). Each variant was tested both individually and collectively using a weighted risk score. APOE-e4 associated with worse baseline memory and increased decline with highly significant overall effect on memory. CLU-rs11136000-G associated with worse baseline memory and incident MCI/LOAD. MS4A6A-rs610932-C associated with increased incident MCI/LOAD and suggestively with lower baseline memory. ABCA7-rs3764650-C and EPHA1-rs11767557-A associated with increased rates of memory decline in subjects with a final diagnosis of MCI/LOAD. PICALM-rs3851179-G had an unexpected protective effect on incident MCI/LOAD. Only APOE-inclusive risk scores associated with worse memory and incident MCI/LOAD. The collective influence of the nine top LOAD GWAS variants on memory decline and progression to MCI/LOAD appears limited. Discovery of biologically functional variants at these loci may uncover stronger effects on memory and incident disease. Copyright © 2015 Elsevier Inc. All rights reserved.

Genomic constitution of an H-2:Tla variant leukemia.

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Shen, F W; Chaganti, R S; Doucette, L A; Litman, G W; Steinmetz, M; Hood, L; Boyse, E A

1984-10-01

A TL+ leukemia of a (B6 X A)F1 hybrid mouse (H-2b/H-2a) was previously subjected to immunoselection against H-2a by passage in (B6 X A.SW)F1 mice (H-2b/H-2s). A variant leukemia line was obtained that serologically lacked not only the H-2a phenotype but also the TL phenotype determined by the linked cis Tlaa allele of strain A. The H-2b phenotype and the TL phenotype of the Tlab allele of the B6 strain, which is expressed only by leukemia cells, were retained by the variant. Southern blotting with an H-2 cDNA probe that identifies restriction fragment polymorphisms distinguishing alleles of the H-2 and Tla regions of the B6 and A strains indicates that both the H-2a and Tlaa alleles are missing from the genome of this H-2a:Tlaa negative variant. Since the variant has two apparently unaltered chromosomes 17, where the H-2:Tla complex is situated, and since the intensity of bands in Southern blotting is suggestive of H-2b homozygosity, it is considered that loss of the H-2a:Tlaa haplotype by the variant was accompanied by duplication of the H-2b:Tlab haplotype. The implied change from heterozygosity to homozygosity that the variant has undergone with respect to H-2:Tla was not paralleled by a similar change at the three other loci tested, since the variant retained heterozygosity for Pep-3 (chromosome 1), Gpi-1 (chromosome 7), and Es-1 (chromosome 8).

Relation of the Allelic Variants of Multidrug Resistance Gene to Agranulocytosis Associated With Clozapine.

Science.gov (United States)

Anıl Yağcioğlu, A Elif; Yoca, Gökhan; Ayhan, Yavuz; Karaca, R Özgür; Çevik, Lokman; Müderrisoğlu, Ahmet; Göktaş, Mustafa T; Eni, Nurhayat; Yazıcı, M Kâzım; Bozkurt, Atilla; Babaoğlu, Melih O

2016-06-01

Clozapine use is associated with leukopenia and more rarely agranulocytosis, which may be lethal. The drug and its metabolites are proposed to interact with the multidrug resistance transporter (ABCB1/MDR1) gene product, P-glycoprotein (P-gp). Among various P-glycoprotein genetic polymorphisms, nucleotide changes in exons 26 (C3435T), 21 (G2677T), and 12 (C1236T) have been implicated for changes in pharmacokinetics and pharmacodynamics of many substrate drugs. In this study, we aimed to investigate the association between these specific ABCB1 polymorphisms and clozapine-associated agranulocytosis (CAA). Ten patients with a history of CAA and 91 control patients without a history of CAA, despite 10 years of continuous clozapine use, were included. Patient recruitment and blood sample collection were conducted at the Hacettepe University Faculty of Medicine, Department of Psychiatry, in collaboration with the members of the Schizophrenia and Other Psychotic Disorders Section of the Psychiatric Association of Turkey, working in various psychiatry clinics. After DNA extraction from peripheral blood lymphocytes, genotyping was performed using polymerase chain reaction and endonuclease digestion. Patients with CAA had shorter duration of clozapine use but did not show any significant difference in other clinical, sociodemographic characteristics and in genotypic or allelic distributions of ABCB1 variants and haplotypes compared with control patients. Among the 10 patients with CAA, none carried the ABCB1 all-variant haplotype (TT-TT-TT), whereas the frequency of this haplotype was approximately 12% among the controls. Larger sample size studies and thorough genetic analyses may reveal both genetic risk and protective factors for this serious adverse event.

Variant alleles of the CYP1B1 gene are associated with colorectal cancer susceptibility

International Nuclear Information System (INIS)

Trubicka, Joanna; Byrski, Tomasz; Gronwald, Jacek; Złowocka, Elżbieta; Kładny, Józef; Banaszkiewicz, Zbigniew; Wiśniowski, Rafał; Kowalska, Elżbieta; Lubinski, Jan; Scott, Rodney J; Grabowska-Kłujszo, Ewa; Suchy, Janina; Masojć, Bartłomiej; Serrano-Fernandez, Pablo; Kurzawski, Grzegorz; Cybulski, Cezary; Górski, Bohdan; Huzarski, Tomasz

2010-01-01

CYP1B1 is a P450 enzyme which is involved in the activation of pro-carcinogens to carcinogens as well as sex hormone metabolism. Because differences in the activity of the enzyme have been correlated with variant alleles of single nucleotide polymorphisms (SNPs), it represents an attractive candidate gene for studies into colorectal cancer susceptibility. We genotyped 597 cancer patients and 597controls for three CYP1B1 SNPs, which have previously been shown to be associated with altered enzymatic activity. Using the three SNPs, eight different haplotypes were constructed. The haplotype frequencies were estimated in cases and controls and then compared. The odds ratio for each tumour type, associated with each haplotype was estimated, with reference to the most common haplotype observed in the controls. The three SNPs rs10012, rs1056827 and rs1056836 alone did not provide any significant evidence of association with colorectal cancer risk. Haplotypes of rs1056827 and rs10012 or rs1056827 and rs1056836 revealed an association with colorectal cancer which was significantly stronger in the homozygous carriers. One haplotype was under represented in the colorectal cancer patient group compared to the control population suggesting a protective effect. Genetic variants within the CYP1B1 that are associated with altered function appear to influence susceptibility to a colorectal cancer in Poland. Three haplotypes were associated with altered cancer risk; one conferred protection and two were associated with an increased risk of disease. These observations should be confirmed in other populations

Variant alleles of the CYP1B1 gene are associated with colorectal cancer susceptibility

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Trubicka Joanna

2010-08-01

Full Text Available Abstract Background CYP1B1 is a P450 enzyme which is involved in the activation of pro-carcinogens to carcinogens as well as sex hormone metabolism. Because differences in the activity of the enzyme have been correlated with variant alleles of single nucleotide polymorphisms (SNPs, it represents an attractive candidate gene for studies into colorectal cancer susceptibility. Methods We genotyped 597 cancer patients and 597controls for three CYP1B1 SNPs, which have previously been shown to be associated with altered enzymatic activity. Using the three SNPs, eight different haplotypes were constructed. The haplotype frequencies were estimated in cases and controls and then compared. The odds ratio for each tumour type, associated with each haplotype was estimated, with reference to the most common haplotype observed in the controls. Results The three SNPs rs10012, rs1056827 and rs1056836 alone did not provide any significant evidence of association with colorectal cancer risk. Haplotypes of rs1056827 and rs10012 or rs1056827 and rs1056836 revealed an association with colorectal cancer which was significantly stronger in the homozygous carriers. One haplotype was under represented in the colorectal cancer patient group compared to the control population suggesting a protective effect. Conclusion Genetic variants within the CYP1B1 that are associated with altered function appear to influence susceptibility to a colorectal cancer in Poland. Three haplotypes were associated with altered cancer risk; one conferred protection and two were associated with an increased risk of disease. These observations should be confirmed in other populations.

Early effect of ApoE-epsilon 4 allele on cognitive results in a group of highly performing subjects: the EVA study. Etude sur le Vieillissement Artériel.

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Berr, C; Dufouil, C; Brousseau, T; Richard, F; Amouyel, P; Marceteau, E; Alpérovitch, A

1996-10-25

We examined the association between apolipoprotein E (ApoE) epsilon 4 allele and cognitive performances in a population sample of 1174 high functioning volunteers aged 59-71 years. The neuropsychological battery included the Mini Mental State Examination (MMSE) and nine tests assessing visual attention, verbal memory, visual processing, logical reasoning, psychomotor rapidity, visual memory, auditory attention and verbal fluency. The ratio of genotypes with zero, one or two epsilon 4 alleles was 70.6%, 21.4% and 1.9%, respectively. The epsilon 4 allele was significantly associated with lower scores for visual attention, psychomotor rapidity and MMSE. In the best performer subgroup (MMSE score above 25, n = 1028), all relationships persisted. Our findings demonstrate that the ApoE-epsilon 4 allele is early associated with low normal cognitive performances in areas which are not specifically affected at the subclinical onset of dementia.

Evaluation of the role of SNCA variants in survival without neurological disease.

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Michael G Heckman

Full Text Available A variety of definitions of successful aging have been proposed, many of which relate to longevity, freedom from disease and disability, or preservation of high physical and cognitive function. Many behavioral, biomedical, and psychological factors have been linked with these various measures of successful aging, however genetic predictors are less understood. Parkinson's disease (PD is an age-related neurodegenerative disorder, and variants in the α-synuclein gene (SNCA affect susceptibility to PD. This exploratory study examined whether SNCA variants may also promote successful aging as defined by survival without neurological disease.We utilized 769 controls without neurological disease (Mean age: 79 years, Range: 33-99 years and examined the frequency of 20 different SNCA variants across age groups using logistic regression models. We also included 426 PD cases to assess the effect of these variants on PD risk.There was a significant decline in the proportion of carriers of the minor allele of rs10014396 as age increased (P = 0.021, from 30% in controls younger than 60 to 14% in controls 90 years of age or older. Findings were similar for rs3775439, where the proportion of carriers of the minor allele declined from 32% in controls less than 60 years old to 19% in those 90 or older (P = 0.025. A number of SNCA variants, not including rs10014396 or rs3775439, were significantly associated with susceptibility to PD.In addition to its documented roles in PD and α-synucleinopathies, our results suggest that SNCA has a role in survival free of neurological disease. Acknowledging that our findings would not have withstood correction for multiple testing, validation in an independent series of aged neurologically normal controls is needed.

Investigation of Genetic Variants Associated with Alzheimer Disease in Parkinson Disease Cognition.

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Barrett, Matthew J; Koeppel, Alexander F; Flanigan, Joseph L; Turner, Stephen D; Worrall, Bradford B

2016-01-01

Meta-analysis of genome-wide association studies have implicated multiple single nucleotide polymorphisms (SNPs) and associated genes with Alzheimer disease. The role of these SNPs in cognitive impairment in Parkinson disease (PD) remains incompletely evaluated. The objective of this study was to test alleles associated with risk of Alzheimer disease for association with cognitive impairment in Parkinson disease (PD). Two datasets with PD subjects accessed through the NIH database of Genotypes and Phenotypes contained both single nucleotide polymorphism (SNP) arrays and mini-mental state exam (MMSE) scores. Genetic data underwent rigorous quality control and we selected SNPs for genes associated with AD other than APOE. We constructed logistic regression and ordinal regression models, adjusted for sex, age at MMSE, and duration of PD, to assess the association between selected SNPs and MMSE score. In one dataset, PICALM rs3851179 was associated with cognitive impairment (MMSE  70 years old (OR = 2.3; adjusted p-value = 0.017; n = 250) but not in PD subjects ≤ 70 years old. Our finding suggests that PICALM rs3851179 could contribute to cognitive impairment in older patients with PD. It is important that future studies consider the interaction of age and genetic risk factors in the development of cognitive impairment in PD.

Severe hypertriglyceridemia in a patient heterozygous for a lipoprotein lipase gene allele with two novel missense variants.

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Kassner, Ursula; Salewsky, Bastian; Wühle-Demuth, Marion; Szijarto, Istvan Andras; Grenkowitz, Thomas; Binner, Priska; März, Winfried; Steinhagen-Thiessen, Elisabeth; Demuth, Ilja

2015-09-01

Rare monogenic hyperchylomicronemia is caused by loss-of-function mutations in genes involved in the catabolism of triglyceride-rich lipoproteins, including the lipoprotein lipase gene, LPL. Clinical hallmarks of this condition are eruptive xanthomas, recurrent pancreatitis and abdominal pain. Patients with LPL deficiency and severe or recurrent pancreatitis are eligible for the first gene therapy treatment approved by the European Union. Therefore the precise molecular diagnosis of familial hyperchylomicronemia may affect treatment decisions. We present a 57-year-old male patient with excessive hypertriglyceridemia despite intensive lipid-lowering therapy. Abdominal sonography showed signs of chronic pancreatitis. Direct DNA sequencing and cloning revealed two novel missense variants, c.1302A>T and c.1306G>A, in exon 8 of the LPL gene coexisting on the same allele. The variants result in the amino-acid exchanges p.(Lys434Asn) and p.(Gly436Arg). They are located in the carboxy-terminal domain of lipoprotein lipase that interacts with the glycosylphosphatidylinositol-anchored HDL-binding protein (GPIHBP1) and are likely of functional relevance. No further relevant mutations were found by direct sequencing of the genes for APOA5, APOC2, LMF1 and GPIHBP1. We conclude that heterozygosity for damaging mutations of LPL may be sufficient to produce severe hypertriglyceridemia and that chylomicronemia may be transmitted in a dominant manner, at least in some families.

Frequency of a FAS ligand gene variant associated with inherited feline autoimmune lymphoproliferative syndrome in British shorthair cats in New Zealand.

Science.gov (United States)

Aberdein, D; Munday, J S; Dittmer, K E; Heathcott, R W; Lyons, L A

2017-11-01

AIMS To determine the frequency of the FAS-ligand gene (FASLG) variant associated with feline autoimmune lymphoproliferative syndrome (FALPS) and the proportion of carriers of the variant in three British shorthair (BSH) breeding catteries in New Zealand. METHODS Buccal swabs were collected from all cats in two BSH breeding catteries from the South Island and one from the North Island of New Zealand. DNA was extracted and was tested for the presence of the FASLG variant using PCR. Cats with the FASLG variant were identified and the frequency of the FASLG variant allele calculated. Pedigree analysis was performed and inbreeding coefficients were calculated for cats with the FASLG variant. RESULTS Of 32 BSH cats successfully tested for the presence of the FASLG variant, one kitten (3%) was homozygous (FALPS-affected), and seven (22%) cats were heterozygous (carriers) for the FASLG variant allele, and 24 (75%) cats were homozygous for the wild type allele. The overall frequency of the FASLG variant allele in these 32 cats was 0.14. Cats carrying the FASLG variant were from all three breeding catteries sampled, including two catteries that had not previously reported cases of FALPS. Pedigree analysis revealed common ancestry of FALPS-affected and carrier cats within six generations, as well as frequent inbreeding, with inbreeding coefficients >0.12 for five cats with the FASLG variant. CONCLUSIONS AND CLINICAL RELEVANCE There was a high frequency of the FASLG variant allele (0.14) in this small sample of BSH cats, with 22% of healthy cats identified as carriers of the FASLG variant. For an inherited disease, lethal at a young age, in a small population in which inbreeding is common, these results are significant. To prevent future cases of disease and stop further spread of the FASLG variant allele within the BSH population in New Zealand, it is recommended that all BSH and BSH-cross cats be tested for the presence of the FASLG variant before mating. Cats identified as

Genetic dissection of the Drosophila melanogaster female head transcriptome reveals widespread allelic heterogeneity.

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King, Elizabeth G; Sanderson, Brian J; McNeil, Casey L; Long, Anthony D; Macdonald, Stuart J

2014-05-01

Modern genetic mapping is plagued by the "missing heritability" problem, which refers to the discordance between the estimated heritabilities of quantitative traits and the variance accounted for by mapped causative variants. One major potential explanation for the missing heritability is allelic heterogeneity, in which there are multiple causative variants at each causative gene with only a fraction having been identified. The majority of genome-wide association studies (GWAS) implicitly assume that a single SNP can explain all the variance for a causative locus. However, if allelic heterogeneity is prevalent, a substantial amount of genetic variance will remain unexplained. In this paper, we take a haplotype-based mapping approach and quantify the number of alleles segregating at each locus using a large set of 7922 eQTL contributing to regulatory variation in the Drosophila melanogaster female head. Not only does this study provide a comprehensive eQTL map for a major community genetic resource, the Drosophila Synthetic Population Resource, but it also provides a direct test of the allelic heterogeneity hypothesis. We find that 95% of cis-eQTLs and 78% of trans-eQTLs are due to multiple alleles, demonstrating that allelic heterogeneity is widespread in Drosophila eQTL. Allelic heterogeneity likely contributes significantly to the missing heritability problem common in GWAS studies.

The NOS1 variant rs6490121 is associated with variation in prefrontal function and grey matter density in healthy individuals.

LENUS (Irish Health Repository)

Rose, Emma J

2012-03-01

A common polymorphism within the nitric oxide sythanse-1 (NOS1) gene (rs6490121), initially identified as risk variant for schizophrenia, has been associated with variation in working memory and IQ. Here we investigated how this variation might be mediated at the level of brain structure and function. In healthy individuals (N=157), voxel based morphometry was used to compare grey matter (GM) volume between homozygous and heterozygous carriers of the \\'G\\' allele (i.e. the allele associated with impaired cognition and schizophrenia risk) and homozygous carriers of the non-risk \\'A\\' allele. Functional brain imaging data were also acquired from 48 participants during performance of a spatial working memory (SWM) task, and analysed to determine any effect of NOS1 risk status. An a priori region-of-interest analysis identified a significant reduction in ventromedial prefrontal GM volume in \\'G\\' allele carriers. Risk carriers also exhibited altered patterns of activation in the prefrontal cortex, caudate, and superior parietal lobe, which were characteristic of abnormal increases in activation in frontoparietal working memory networks and a failure to disengage regions of the default mode network. These functional changes suggest a NOS1-mediated processing inefficiency, which may contribute to cognitive dysfunction in schizophrenia. While the mechanisms by which NOS1 may influence brain structure and\\/or function have not yet been well delineated, these data provide further evidence for a role of NOS1 in risk for schizophrenia via an impact upon cognitive function.

A functional MiR-124 binding-site polymorphism in IQGAP1 affects human cognitive performance.

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Lixin Yang

Full Text Available As a product of the unique evolution of the human brain, human cognitive performance is largely a collection of heritable traits. Rather surprisingly, to date there have been no reported cases to highlight genes that underwent adaptive evolution in humans and which carry polymorphisms that have a marked effect on cognitive performance. IQ motif containing GTPase activating protein 1 (IQGAP1, a scaffold protein, affects learning and memory in a dose-dependent manner. Its expression is regulated by miR-124 through the binding sites in the 3'UTR, where a SNP (rs1042538 exists in the core-binding motif. Here we showed that this SNP can influence the miR-target interaction both in vitro and in vivo. Individuals carrying the derived T alleles have higher IQGAP1 expression in the brain as compared to the ancestral A allele carriers. We observed a significant and male-specific association between rs1042538 and tactile performances in two independent cohorts. Males with the derived allele displayed higher tactual performances as compared to those with the ancestral allele. Furthermore, we found a highly diverged allele-frequency distribution of rs1042538 among world human populations, likely caused by natural selection and/or recent population expansion. These results suggest that current human populations still carry sequence variations that affect cognitive performances and that these genetic variants may likely have been subject to comparatively recent natural selection.

TaGW2-6A allelic variation contributes to grain size possibly by regulating the expression of cytokinins and starch-related genes in wheat.

Science.gov (United States)

Geng, Juan; Li, Liqun; Lv, Qian; Zhao, Yi; Liu, Yan; Zhang, Li; Li, Xuejun

2017-12-01

Functional allelic variants of TaGW2 - 6A produce large grains, possibly via changes in endosperm cells and dry matter by regulating the expression of cytokinins and starch-related genes via the ubiquitin-proteasome system. In wheat, TaGW2-6A coding region allelic variants are closely related to the grain width and weight, but how this region affects grain development has not been fully elucidated; thus, we explored its influence on grain development based mainly on histological and grain filling analyses. We found that the insertion type (NIL31) TaGW2-6A allelic variants exhibited increases in cell numbers and cell size, thereby resulting in a larger (wider) grain size with an accelerated grain milk filling rate, and increases in grain width and weight. We also found that cytokinin (CK) synthesis genes and key starch biosynthesis enzyme AGPase genes were significantly upregulated in the TaGW2-6A allelic variants, while CK degradation genes and starch biosynthesis-negative regulators were downregulated in the TaGW2-6A allelic variants, which was consistent with the changes in cells and grain filling. Thus, we speculate that TaGW2-6A allelic variants are linked with CK signaling, but they also influence the accumulation of starch by regulating the expression of related genes via the ubiquitin-proteasome system to control the grain size and grain weight.

ALEA: a toolbox for allele-specific epigenomics analysis.

Science.gov (United States)

Younesy, Hamid; Möller, Torsten; Heravi-Moussavi, Alireza; Cheng, Jeffrey B; Costello, Joseph F; Lorincz, Matthew C; Karimi, Mohammad M; Jones, Steven J M

2014-04-15

The assessment of expression and epigenomic status using sequencing based methods provides an unprecedented opportunity to identify and correlate allelic differences with epigenomic status. We present ALEA, a computational toolbox for allele-specific epigenomics analysis, which incorporates allelic variation data within existing resources, allowing for the identification of significant associations between epigenetic modifications and specific allelic variants in human and mouse cells. ALEA provides a customizable pipeline of command line tools for allele-specific analysis of next-generation sequencing data (ChIP-seq, RNA-seq, etc.) that takes the raw sequencing data and produces separate allelic tracks ready to be viewed on genome browsers. The pipeline has been validated using human and hybrid mouse ChIP-seq and RNA-seq data. The package, test data and usage instructions are available online at http://www.bcgsc.ca/platform/bioinfo/software/alea CONTACT: : mkarimi1@interchange.ubc.ca or sjones@bcgsc.ca Supplementary information: Supplementary data are available at Bioinformatics online. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

A putative Alzheimer's disease risk allele in PCK1 influences brain atrophy in multiple sclerosis.

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Zongqi Xia

2010-11-01

Full Text Available Brain atrophy and cognitive dysfunction are neurodegenerative features of Multiple Sclerosis (MS. We used a candidate gene approach to address whether genetic variants implicated in susceptibility to late onset Alzheimer's Disease (AD influence brain volume and cognition in MS patients.MS subjects were genotyped for five single nucleotide polymorphisms (snps associated with susceptibility to AD: PICALM, CR1, CLU, PCK1, and ZNF224. We assessed brain volume using Brain Parenchymal Fraction (BPF measurements obtained from Magnetic Resonance Imaging (MRI data and cognitive function using the Symbol Digit Modalities Test (SDMT. Genotypes were correlated with cross-sectional BPF and SDMT scores using linear regression after adjusting for sex, age at symptom onset, and disease duration. 722 MS patients with a mean (±SD age at enrollment of 41 (±10 years were followed for 44 (±28 months. The AD risk-associated allele of a non-synonymous SNP in the PCK1 locus (rs8192708G is associated with a smaller average brain volume (P=0.0047 at the baseline MRI, but it does not impact our baseline estimate of cognition. PCK1 is additionally associated with higher baseline T2-hyperintense lesion volume (P=0.0088. Finally, we provide technical validation of our observation in a subset of 641 subjects that have more than one MRI study, demonstrating the same association between PCK1 and smaller average brain volume (P=0.0089 at the last MRI visit.Our study provides suggestive evidence for greater brain atrophy in MS patients bearing the PCK1 allele associated with AD-susceptibility, yielding new insights into potentially shared neurodegenerative process between MS and late onset AD.

Geographical gradient of the eIF4E alleles conferring resistance to potyviruses in pea (Pisum) germplasm.

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Konečná, Eva; Šafářová, Dana; Navrátil, Milan; Hanáček, Pavel; Coyne, Clarice; Flavell, Andrew; Vishnyakova, Margarita; Ambrose, Mike; Redden, Robert; Smýkal, Petr

2014-01-01

The eukaryotic translation initiation factor 4E was shown to be involved in resistance against several potyviruses in plants, including pea. We combined our knowledge of pea germplasm diversity with that of the eIF4E gene to identify novel genetic diversity. Germplasm of 2803 pea accessions was screened for eIF4E intron 3 length polymorphism, resulting in the detection of four eIF4E(A-B-C-S) variants, whose distribution was geographically structured. The eIF4E(A) variant conferring resistance to the P1 PSbMV pathotype was found in 53 accessions (1.9%), of which 15 were landraces from India, Afghanistan, Nepal, and 7 were from Ethiopia. A newly discovered variant, eIF4E(B), was present in 328 accessions (11.7%) from Ethiopia (29%), Afghanistan (23%), India (20%), Israel (25%) and China (39%). The eIF4E(C) variant was detected in 91 accessions (3.2% of total) from India (20%), Afghanistan (33%), the Iberian Peninsula (22%) and the Balkans (9.3%). The eIF4E(S) variant for susceptibility predominated as the wild type. Sequencing of 73 samples, identified 34 alleles at the whole gene, 26 at cDNA and 19 protein variants, respectively. Fifteen alleles were virologically tested and 9 alleles (eIF4E(A-1-2-3-4-5-6-7), eIF4E(B-1), eIF4E(C-2)) conferred resistance to the P1 PSbMV pathotype. This work identified novel eIF4E alleles within geographically structured pea germplasm and indicated their independent evolution from the susceptible eIF4E(S1) allele. Despite high variation present in wild Pisum accessions, none of them possessed resistance alleles, supporting a hypothesis of distinct mode of evolution of resistance in wild as opposed to crop species. The Highlands of Central Asia, the northern regions of the Indian subcontinent, Eastern Africa and China were identified as important centers of pea diversity that correspond with the diversity of the pathogen. The series of alleles identified in this study provides the basis to study the co-evolution of potyviruses and the

A new detection method for the K variant of butyrylcholinesterase based on PCR primer introduced restriction analysis (PCR-PIRA).

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Shibuta, K; Abe, M; Suzuki, T

1994-01-01

The K variant of human butyrylcholinesterase is caused by a G/A transition in the butyrylcholinesterase gene, which neither creates nor destroys any restriction site. In an attempt to detect the K variant both simply and rapidly, we developed a two step method of "PCR primer introduced restriction analysis" (PCR-PIRA). The first step was used to introduce a new Fun4HI site into the normal allele for a screening test, while the second step was performed to create a new MaeIII site on the variant allele for a specific test. This method thus enabled us to distinguish clearly the K variant from the normal allele, and also showed that the frequency of the K variant allele is 0.164 in the Japanese population. Images PMID:7966197

Detecting rare variants in case-parents association studies.

Directory of Open Access Journals (Sweden)

Kuang-Fu Cheng

Full Text Available Despite the success of genome-wide association studies (GWASs in detecting common variants (minor allele frequency ≥0.05 many suggested that rare variants also contribute to the genetic architecture of diseases. Recently, researchers demonstrated that rare variants can show a strong stratification which may not be corrected by using existing methods. In this paper, we focus on a case-parents study and consider methods for testing group-wise association between multiple rare (and common variants in a gene region and a disease. All tests depend on the numbers of transmitted mutant alleles from parents to their diseased children across variants and hence they are robust to the effect of population stratification. We use extensive simulation studies to compare the performance of four competing tests: the largest single-variant transmission disequilibrium test (TDT, multivariable test, combined TDT, and a likelihood ratio test based on a random-effects model. We find that the likelihood ratio test is most powerful in a wide range of settings and there is no negative impact to its power performance when common variants are also included in the analysis. If deleterious and protective variants are simultaneously analyzed, the likelihood ratio test was generally insensitive to the effect directionality, unless the effects are extremely inconsistent in one direction.

Cystic fibrosis transmembrane conductance regulator (CFTR allelic variants relate to shifts in faecal microbiota of cystic fibrosis patients.

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Serena Schippa

Full Text Available INTRODUCTION: In this study we investigated the effects of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR gene variants on the composition of faecal microbiota, in patients affected by Cystic Fibrosis (CF. CFTR mutations (F508del is the most common lead to a decreased secretion of chloride/water, and to mucus sticky secretions, in pancreas, respiratory and gastrointestinal tracts. Intestinal manifestations are underestimated in CF, leading to ileum meconium at birth, or small bowel bacterial overgrowth in adult age. METHODS: Thirty-six CF patients, fasting and under no-antibiotic treatment, were CFTR genotyped on both alleles. Faecal samples were subjected to molecular microbial profiling through Temporal Temperature Gradient Electrophoresis and species-specific PCR. Ecological parameters and multivariate algorithms were employed to find out if CFTR variants could be related to the microbiota structure. RESULTS: Patients were classified by two different criteria: 1 presence/absence of F508del mutation; 2 disease severity in heterozygous and homozygous F508del patients. We found that homozygous-F508del and severe CF patients exhibited an enhanced dysbiotic faecal microbiota composition, even within the CF cohort itself, with higher biodiversity and evenness. We also found, by species-specific PCR, that potentially harmful species (Escherichia coli and Eubacterium biforme were abundant in homozygous-F508del and severe CF patients, while beneficial species (Faecalibacterium prausnitzii, Bifidobacterium spp., and Eubacterium limosum were reduced. CONCLUSIONS: This is the first report that establishes a link among CFTR variants and shifts in faecal microbiota, opening the way to studies that perceive CF as a 'systemic disease', linking the lung and the gut in a joined axis.

Cystic fibrosis transmembrane conductance regulator (CFTR) allelic variants relate to shifts in faecal microbiota of cystic fibrosis patients.

Science.gov (United States)

Schippa, Serena; Iebba, Valerio; Santangelo, Floriana; Gagliardi, Antonella; De Biase, Riccardo Valerio; Stamato, Antonella; Bertasi, Serenella; Lucarelli, Marco; Conte, Maria Pia; Quattrucci, Serena

2013-01-01

In this study we investigated the effects of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene variants on the composition of faecal microbiota, in patients affected by Cystic Fibrosis (CF). CFTR mutations (F508del is the most common) lead to a decreased secretion of chloride/water, and to mucus sticky secretions, in pancreas, respiratory and gastrointestinal tracts. Intestinal manifestations are underestimated in CF, leading to ileum meconium at birth, or small bowel bacterial overgrowth in adult age. Thirty-six CF patients, fasting and under no-antibiotic treatment, were CFTR genotyped on both alleles. Faecal samples were subjected to molecular microbial profiling through Temporal Temperature Gradient Electrophoresis and species-specific PCR. Ecological parameters and multivariate algorithms were employed to find out if CFTR variants could be related to the microbiota structure. Patients were classified by two different criteria: 1) presence/absence of F508del mutation; 2) disease severity in heterozygous and homozygous F508del patients. We found that homozygous-F508del and severe CF patients exhibited an enhanced dysbiotic faecal microbiota composition, even within the CF cohort itself, with higher biodiversity and evenness. We also found, by species-specific PCR, that potentially harmful species (Escherichia coli and Eubacterium biforme) were abundant in homozygous-F508del and severe CF patients, while beneficial species (Faecalibacterium prausnitzii, Bifidobacterium spp., and Eubacterium limosum) were reduced. This is the first report that establishes a link among CFTR variants and shifts in faecal microbiota, opening the way to studies that perceive CF as a 'systemic disease', linking the lung and the gut in a joined axis.

Candidate Cancer Allele cDNA Collection | Office of Cancer Genomics

Science.gov (United States)

CTD2 researchers at the Broad Institute/DFCI have developed a collection of plasmids including mutant alleles found in sequencing studies of cancer. It includes somatic variants found in lung adenocarcinoma and across other cancer types. The clones enable researchers to characterize the function of the cancer variants in a high throughput experiments. These plasmids are collectively called the “Broad Target Accelerator Plasmid Collections”.

Clinical Utility of Short Social Cognitive Tests in Early Differentiation of Behavioral Variant Frontotemporal Dementia from Alzheimer’s Disease

DEFF Research Database (Denmark)

Buhl, Christian; Stokholm, Jette; Gade, Anders

2013-01-01

Traditional cognitive tests used in clinical practice may not be sensitive enough for the early differentiation of behavioral variant frontotemporal dementia (bvFTD) from Alzheimer's disease (AD). A growing body of literature has shown that deficits in various aspects of social cognition can be f...

Poisson Approximation-Based Score Test for Detecting Association of Rare Variants.

Science.gov (United States)

Fang, Hongyan; Zhang, Hong; Yang, Yaning

2016-07-01

Genome-wide association study (GWAS) has achieved great success in identifying genetic variants, but the nature of GWAS has determined its inherent limitations. Under the common disease rare variants (CDRV) hypothesis, the traditional association analysis methods commonly used in GWAS for common variants do not have enough power for detecting rare variants with a limited sample size. As a solution to this problem, pooling rare variants by their functions provides an efficient way for identifying susceptible genes. Rare variant typically have low frequencies of minor alleles, and the distribution of the total number of minor alleles of the rare variants can be approximated by a Poisson distribution. Based on this fact, we propose a new test method, the Poisson Approximation-based Score Test (PAST), for association analysis of rare variants. Two testing methods, namely, ePAST and mPAST, are proposed based on different strategies of pooling rare variants. Simulation results and application to the CRESCENDO cohort data show that our methods are more powerful than the existing methods. © 2016 John Wiley & Sons Ltd/University College London.

Genetic dissection of the Drosophila melanogaster female head transcriptome reveals widespread allelic heterogeneity.

Directory of Open Access Journals (Sweden)

Elizabeth G King

2014-05-01

Full Text Available Modern genetic mapping is plagued by the "missing heritability" problem, which refers to the discordance between the estimated heritabilities of quantitative traits and the variance accounted for by mapped causative variants. One major potential explanation for the missing heritability is allelic heterogeneity, in which there are multiple causative variants at each causative gene with only a fraction having been identified. The majority of genome-wide association studies (GWAS implicitly assume that a single SNP can explain all the variance for a causative locus. However, if allelic heterogeneity is prevalent, a substantial amount of genetic variance will remain unexplained. In this paper, we take a haplotype-based mapping approach and quantify the number of alleles segregating at each locus using a large set of 7922 eQTL contributing to regulatory variation in the Drosophila melanogaster female head. Not only does this study provide a comprehensive eQTL map for a major community genetic resource, the Drosophila Synthetic Population Resource, but it also provides a direct test of the allelic heterogeneity hypothesis. We find that 95% of cis-eQTLs and 78% of trans-eQTLs are due to multiple alleles, demonstrating that allelic heterogeneity is widespread in Drosophila eQTL. Allelic heterogeneity likely contributes significantly to the missing heritability problem common in GWAS studies.

Rare and low-frequency coding variants alter human adult height

DEFF Research Database (Denmark)

Marouli, Eirini; Graff, Mariaelisa; Medina-Gomez, Carolina

2017-01-01

to 2 centimetres per allele (such as those in IHH, STC2, AR and CRISPLD2), greater than ten times the average effect of common variants. In functional follow-up studies, rare height-increasing alleles of STC2 (giving an increase of 1-2 centimetres per allele) compromised proteolytic inhibition of PAPP...

Allelic variants of OsSUB1A cause differential expression of transcription factor genes in response to submergence in rice.

Science.gov (United States)

Sharma, Niharika; Dang, Trang Minh; Singh, Namrata; Ruzicic, Slobodan; Mueller-Roeber, Bernd; Baumann, Ute; Heuer, Sigrid

2018-01-08

Flooding during seasonal monsoons affects millions of hectares of rice-cultivated areas across Asia. Submerged rice plants die within a week due to lack of oxygen, light and excessive elongation growth to escape the water. Submergence tolerance was first reported in an aus-type rice landrace, FR13A, and the ethylene-responsive transcription factor (TF) gene SUB1A-1 was identified as the major tolerance gene. Intolerant rice varieties generally lack the SUB1A gene but some intermediate tolerant varieties, such as IR64, carry the allelic variant SUB1A-2. Differential effects of the two alleles have so far not been addressed. As a first step, we have therefore quantified and compared the expression of nearly 2500 rice TF genes between IR64 and its derived tolerant near isogenic line IR64-Sub1, which carries the SUB1A-1 allele. Gene expression was studied in internodes, where the main difference in expression between the two alleles was previously shown. Nineteen and twenty-six TF genes were identified that responded to submergence in IR64 and IR64-Sub1, respectively. Only one gene was found to be submergence-responsive in both, suggesting different regulatory pathways under submergence in the two genotypes. These differentially expressed genes (DEGs) mainly included MYB, NAC, TIFY and Zn-finger TFs, and most genes were downregulated upon submergence. In IR64, but not in IR64-Sub1, SUB1B and SUB1C, which are also present in the Sub1 locus, were identified as submergence responsive. Four TFs were not submergence responsive but exhibited constitutive, genotype-specific differential expression. Most of the identified submergence responsive DEGs are associated with regulatory hormonal pathways, i.e. gibberellins (GA), abscisic acid (ABA), and jasmonic acid (JA), apart from ethylene. An in-silico promoter analysis of the two genotypes revealed the presence of allele-specific single nucleotide polymorphisms, giving rise to ABRE, DRE/CRT, CARE and Site II cis-elements, which

Association of breast cancer risk in BRCA1 and BRCA2 mutation carriers with genetic variants showing differential allelic expression: identification of a modifier of breast cancer risk at locus 11q22.3

NARCIS (Netherlands)

Y. Hamdi (Yosr); Soucy, P. (Penny); Kuchenbaeker, K.B. (Karoline B.); Pastinen, T. (Tomi); A. Droit (Arnaud); Lemaçon, A. (Audrey); J.W. Adlard (Julian); K. Aittomäki (Kristiina); I.L. Andrulis (Irene); A. Arason (Adalgeir); N. Arnold (Norbert); B.K. Arun (Banu); J. Azzollini; A.L. Bane (Anita L.); Barjhoux, L. (Laure); D. Barrowdale (Daniel); J. Benítez (Javier); P. Berthet (Pascaline); M.J. Blok (Marinus); K.A. Bobolis (Kristie A.); V. Bonadona (Valérie); B. Bonnani (Bernardo); Bradbury, A.R. (Angela R.); C. Brewer (Carole); B. Buecher (Bruno); Buys, S.S. (Saundra S.); M.A. Caligo (Maria); Chiquette, J. (Jocelyne); W. Chung (Wendy); K.B.M. Claes (Kathleen B.M.); Daly, M.B. (Mary B.); F. Damiola (Francesca); R. Davidson (Rosemarie); M. de La Hoya (Miguel); K. De Leeneer (Kim); O. Díez (Orland); Y.C. Ding (Yuan); R. Dolcetti (Riccardo); S.M. Domchek (Susan); C.M. Dorfling (Cecilia); D. Eccles (Diana); R. Eeles (Ros); Z. Einbeigi (Zakaria); B. Ejlertsen (Bent); EMBRACE; C. Engel (Christoph); Gareth Evans, D.; L. Feliubadaló (L.); L. Foretova (Lenka); F. Fostira (Florentia); Foulkes, W.D. (William D.); G. Fountzilas (George); E. Friedman (Eitan); D. Frost (Debra); P. Ganschow (Pamela); P.A. Ganz (Patricia A.); J. Garber (Judy); S.A. Gayther (Simon); GEMO Study Collaborators; A-M. Gerdes (Anne-Marie); G. Glendon (Gord); A.K. Godwin (Andrew K.); D. Goldgar (David); M.H. Greene (Mark H.); J. Gronwald (Jacek); E. Hahnen (Eric); U. Hamann (Ute); T.V.O. Hansen (Thomas); S. Hart (Stewart); J. Hays (John); HEBON; F.B.L. Hogervorst (Frans); P.J. Hulick (Peter); E.N. Imyanitov (Evgeny); C. Isaacs (Claudine); L. Izatt (Louise); A. Jakubowska (Anna); M. James (Margaret); R. Janavicius (Ramunas); U.B. Jensen; E.M. John (Esther); V. Joseph (Vijai); Just, W. (Walter); Kaczmarek, K. (Katarzyna); Karlan, B.Y. (Beth Y.); KConFab Investigators; C.M. Kets; J. Kirk (Judy); Kriege, M. (Mieke); Y. Laitman (Yael); Laurent, M. (Maïté); C. Lazaro (Conxi); Leslie, G. (Goska); K.J. Lester (Kathryn); F. Lesueur (Fabienne); A. Liljegren (Annelie); N. Loman (Niklas); J.T. Loud (Jennifer); S. Manoukian (Siranoush); Mariani, M. (Milena); S. Mazoyer (Sylvie); L. McGuffog (Lesley); E.J. Meijers-Heijboer (Hanne); A. Meindl (Alfons); A. Miller (Austin); M. Montagna (Marco); A.-M. Mulligan (Anna-Marie); K.L. Nathanson (Katherine); S.L. Neuhausen (Susan); H. Nevanlinna (Heli); R.L. Nussbaum (Robert L.); Olah, E. (Edith); O.I. Olopade (Olufunmilayo I.); K.-R. Ong (Kai-Ren); J.C. Oosterwijk (Jan); A. Osorio (Ana); L. Papi (Laura); S.K. Park (Sue K.); Pedersen, I.S. (Inge Sokilde); B. Peissel (Bernard); P.P. Segura (Pedro Perez); P. Peterlongo (Paolo); C. Phelan (Catherine); P. Radice (Paolo); J. Rantala (Johanna); Rappaport-Fuerhauser, C. (Christine); G. Rennert (Gad); A.L. Richardson (Andrea); M. Robson (Mark); G.C. Rodriguez (Gustavo); M.A. Rookus (Matti); R.K. Schmutzler (Rita); N. Sevenet (Nicolas); Shah, P.D. (Payal D.); C.F. Singer (Christian); Slavin, T.P. (Thomas P.); Snape, K. (Katie); J. Sokolowska (Johanna); Sønderstrup, I.M.H. (Ida Marie Heeholm); M.C. Southey (Melissa); A.B. Spurdle (Amanda); Stadler, Z. (Zsofia); D. Stoppa-Lyonnet (Dominique); G. Sukiennicki (Grzegorz); C. Sutter (Christian); Tan, Y. (Yen); M.-K. Tea; P.J. Teixeira; A. Teulé (A.); S.-H. Teo (Soo-Hwang); M.B. Terry (Mary Beth); M. Thomassen (Mads); L. Tihomirova (Laima); M. Tischkowitz (Marc); S. Tognazzo (Silvia); A.E. Toland (Amanda); N. Tung (Nadine); A.M.W. van den Ouweland (Ans); R.B. van der Luijt (Rob); K. van Engelen (Klaartje); E.J. van Rensburg (Elizabeth); R. Varon-Mateeva (Raymonda); B. Wapenschmidt (Barbara); J.T. Wijnen (Juul); R. Rebbeck (Timothy); G. Chenevix-Trench (Georgia); K. Offit (Kenneth); Couch, F.J. (Fergus J.); S. Nord (Silje); D.F. Easton (Douglas F.); A.C. Antoniou (Antonis C.); Simard, J. (Jacques)

2016-01-01

textabstractPurpose: Cis-acting regulatory SNPs resulting in differential allelic expression (DAE) may, in part, explain the underlying phenotypic variation associated with many complex diseases. To investigate whether common variants associated with DAE were involved in breast cancer susceptibility

Evidence of an association between the Arg72 allele of the peptide YY and increased risk of type 2 diabetes

DEFF Research Database (Denmark)

Torekov, Signe S; Larsen, Lesli H; Glümer, Charlotte

2005-01-01

We tested the hypothesis that variants in the gene encoding the prepropeptide YY (PYY) associate with type 2 diabetes and/or obesity. Mutation analyses of DNA from 84 patients with obesity and familial type 2 diabetes identified two polymorphisms, IVS3 + 68C>T and Arg72Thr, and one rare variant......, +151C>A of PYY. The common allele of the Arg72Thr variant associated with type 2 diabetes with an allele frequency of the Arg allele of 0.667 (95% CI 0.658-0.677) among 4,639 glucose-tolerant subjects and 0.692 (0.674-0.710) among 1,326 patients with type 2 diabetes (P = 0.005, odds ratio 1.19 [95% CI...... tolerance test (OGTT) (P = 0.03), an increased area under the curve for the post-OGTT plasma glucose level (P = 0.03), and a lower insulinogenic index (P = 0.01). In conclusion, the common Arg allele of the PYY Arg72Thr variant modestly associates with type 2 diabetes and with type 2 diabetes...

Association of breast cancer risk in BRCA1 and BRCA2 mutation carriers with genetic variants showing differential allelic expression : identification of a modifier of breast cancer risk at locus 11q22.3

NARCIS (Netherlands)

Hamdi, Yosr; Soucy, Penny; Kuchenbaeker, Karoline B; Pastinen, Tomi; Droit, Arnaud; Lemaçon, Audrey; Adlard, Julian; Aittomäki, Kristiina; Andrulis, Irene L; Arason, Adalgeir; Arnold, Norbert; Arun, Banu K; Azzollini, Jacopo; Bane, Anita; Barjhoux, Laure; Barrowdale, Daniel; Benitez, Javier; Berthet, Pascaline; Blok, Marinus J; Bobolis, Kristie; Bonadona, Valérie; Bonanni, Bernardo; Bradbury, Angela R; Brewer, Carole; Buecher, Bruno; Buys, Saundra S; Caligo, Maria A; Chiquette, Jocelyne; Chung, Wendy K; Claes, Kathleen B M; Daly, Mary B; Damiola, Francesca; Davidson, Rosemarie; De la Hoya, Miguel; De Leeneer, Kim; Diez, Orland; Ding, Yuan Chun; Dolcetti, Riccardo; Domchek, Susan M; Dorfling, Cecilia M; Eccles, Diana; Eeles, Ros; Einbeigi, Zakaria; Ejlertsen, Bent; Engel, Christoph; Gareth Evans, D; Feliubadalo, Lidia; Foretova, Lenka; Fostira, Florentia; Foulkes, William D; Fountzilas, George; Friedman, Eitan; Frost, Debra; Ganschow, Pamela; Ganz, Patricia A; Garber, Judy; Gayther, Simon A; Gerdes, Anne-Marie; Glendon, Gord; Godwin, Andrew K; Goldgar, David E; Greene, Mark H; Gronwald, Jacek; Hahnen, Eric; Hamann, Ute; Hansen, Thomas V O; Hart, Steven; Hays, John L; Hogervorst, Frans B L; Hulick, Peter J; Imyanitov, Evgeny N; Isaacs, Claudine; Izatt, Louise; Jakubowska, Anna; James, Paul; Janavicius, Ramunas; Jensen, Uffe Birk; John, Esther M; Joseph, Vijai; Just, Walter; Kaczmarek, Katarzyna; Karlan, Beth Y; Kets, Carolien M; Kirk, Judy; Kriege, Mieke; Laitman, Yael; Laurent, Maïté; Lazaro, Conxi; Leslie, Goska; Lester, Jenny; Lesueur, Fabienne; Liljegren, Annelie; Loman, Niklas; Loud, Jennifer T; Manoukian, Siranoush; Mariani, Milena; Mazoyer, Sylvie; McGuffog, Lesley; Meijers-Heijboer, Hanne E J; Meindl, Alfons; Miller, Austin; Montagna, Marco; Mulligan, Anna Marie; Nathanson, Katherine L; Neuhausen, Susan L; Nevanlinna, Heli; Nussbaum, Robert L; Olah, Edith; Olopade, Olufunmilayo I; Ong, Kai-Ren; Oosterwijk, Jan C; Osorio, Ana; Papi, Laura; Park, Sue Kyung; Pedersen, Inge Sokilde; Peissel, Bernard; Segura, Pedro Perez; Peterlongo, Paolo; Phelan, Catherine M; Radice, Paolo; Rantala, Johanna; Rappaport-Fuerhauser, Christine; Rennert, Gad; Richardson, Andrea; Robson, Mark; Rodriguez, Gustavo C; Rookus, Matti A; Schmutzler, Rita Katharina; Sevenet, Nicolas; Shah, Payal D; Singer, Christian F; Slavin, Thomas P; Snape, Katie; Sokolowska, Johanna; Sønderstrup, Ida Marie Heeholm; Southey, Melissa; Spurdle, Amanda B; Stadler, Zsofia; Stoppa-Lyonnet, Dominique; Sukiennicki, Grzegorz; Sutter, Christian; Tan, Yen; Tea, Muy-Kheng; Teixeira, Manuel R; Teulé, Alex; Teo, Soo-Hwang; Terry, Mary Beth; Thomassen, Mads; Tihomirova, Laima; Tischkowitz, Marc; Tognazzo, Silvia; Toland, Amanda Ewart; Tung, Nadine; van den Ouweland, Ans M W; van der Luijt, Rob B; van Engelen, Klaartje; van Rensburg, Elizabeth J; Varon-Mateeva, Raymonda; Wappenschmidt, Barbara; Wijnen, Juul T; Rebbeck, Timothy; Chenevix-Trench, Georgia; Offit, Kenneth; Couch, Fergus J; Nord, Silje; Easton, Douglas F; Antoniou, Antonis C; Simard, Jacques

PURPOSE: Cis-acting regulatory SNPs resulting in differential allelic expression (DAE) may, in part, explain the underlying phenotypic variation associated with many complex diseases. To investigate whether common variants associated with DAE were involved in breast cancer susceptibility among BRCA1

A risk allele for nicotine dependence in CHRNA5 is a protective allele for cocaine dependence.

Science.gov (United States)

Grucza, Richard A; Wang, Jen C; Stitzel, Jerry A; Hinrichs, Anthony L; Saccone, Scott F; Saccone, Nancy L; Bucholz, Kathleen K; Cloninger, C Robert; Neuman, Rosalind J; Budde, John P; Fox, Louis; Bertelsen, Sarah; Kramer, John; Hesselbrock, Victor; Tischfield, Jay; Nurnberger, John I; Almasy, Laura; Porjesz, Bernice; Kuperman, Samuel; Schuckit, Marc A; Edenberg, Howard J; Rice, John P; Goate, Alison M; Bierut, Laura J

2008-12-01

A nonsynonymous coding polymorphism, rs16969968, of the CHRNA5 gene that encodes the alpha-5 subunit of the nicotinic acetylcholine receptor (nAChR) has been found to be associated with nicotine dependence. The goal of this study was to examine the association of this variant with cocaine dependence. Genetic association analysis was performed in two independent samples of unrelated case and control subjects: 1) 504 European Americans participating in the Family Study on Cocaine Dependence (FSCD) and 2) 814 European Americans participating in the Collaborative Study on the Genetics of Alcoholism (COGA). In the FSCD, there was a significant association between the CHRNA5 variant and cocaine dependence (odds ratio = .67 per allele, p = .0045, assuming an additive genetic model), but in the reverse direction compared with that previously observed for nicotine dependence. In multivariate analyses that controlled for the effects of nicotine dependence, both the protective effect for cocaine dependence and the previously documented risk effect for nicotine dependence were statistically significant. The protective effect for cocaine dependence was replicated in the COGA sample. In COGA, effect sizes for habitual smoking, a proxy phenotype for nicotine dependence, were consistent with those observed in FSCD. The minor (A) allele of rs16969968, relative to the major G allele, appears to be both a risk factor for nicotine dependence and a protective factor for cocaine dependence. The biological plausibility of such a bidirectional association stems from the involvement of nAChRs with both excitatory and inhibitory modulation of dopamine-mediated reward pathways.

Allelic Dropout in the ENG Gene, Affecting the Results of Genetic Testing in Hereditary Hemorrhagic Telangiectasia

DEFF Research Database (Denmark)

Tørring, Pernille M; Kjeldsen, A.D.; Ousager, L.B.

2012-01-01

Background: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal-dominant vascular disorder with three disease-causing genes identified to date: ENG, ACVRL1, and SMAD4. We report an HHT patient with allelic dropout that on routine sequence analysis for a known mutation in the family (c.817......-3T>G in ENG) initially seemed to be homozygous for the mutation. Aim: To explore the possibility of allelic dropout causing a false result in this patient. Methods: Mutation analysis of additional family members was performed and haplotype analysis carried out. New primers were designed to reveal...... the presence of a possible sequence variant, which could explain the presumed allelic dropout. Results: Allelic dropout caused by a six-nucleotide duplication close to the standard reverse primer was the assumed cause of a false homozygous diagnosis. Conclusion: Sequence variants outside of the primer regions...

Pleiotropic Associations of Allelic Variants in a 2q22 Region with Risks of Major Human Diseases and Mortality.

Directory of Open Access Journals (Sweden)

Alexander M Kulminski

2016-11-01

Full Text Available Gaining insights into genetic predisposition to age-related diseases and lifespan is a challenging task complicated by the elusive role of evolution in these phenotypes. To gain more insights, we combined methods of genome-wide and candidate-gene studies. Genome-wide scan in the Atherosclerosis Risk in Communities (ARIC Study (N = 9,573 was used to pre-select promising loci. Candidate-gene methods were used to comprehensively analyze associations of novel uncommon variants in Caucasians (minor allele frequency~2.5% located in band 2q22.3 with risks of coronary heart disease (CHD, heart failure (HF, stroke, diabetes, cancer, neurodegenerative diseases (ND, and mortality in the ARIC study, the Framingham Heart Study (N = 4,434, and the Health and Retirement Study (N = 9,676. We leveraged the analyses of pleiotropy, age-related heterogeneity, and causal inferences. Meta-analysis of the results from these comprehensive analyses shows that the minor allele increases risks of death by about 50% (p = 4.6×10-9, CHD by 35% (p = 8.9×10-6, HF by 55% (p = 9.7×10-5, stroke by 25% (p = 4.0×10-2, and ND by 100% (p = 1.3×10-3. This allele also significantly influences each of two diseases, diabetes and cancer, in antagonistic fashion in different populations. Combined significance of the pleiotropic effects was p = 6.6×10-21. Causal mediation analyses show that endophenotypes explained only small fractions of these effects. This locus harbors an evolutionary conserved gene-desert region with non-coding intergenic sequences likely involved in regulation of protein-coding flanking genes ZEB2 and ACVR2A. This region is intensively studied for mutations causing severe developmental/genetic disorders. Our analyses indicate a promising target region for interventions aimed to reduce risks of many major human diseases and mortality.

Genetic variants and cognitive aging: destiny or a nudge?

Science.gov (United States)

Raz, Naftali; Lustig, Cindy

2014-06-01

One would be hard-pressed to find a human trait that is not heritable at least to some extent, and genetics have played an important role in behavioral science for more than half a century. With the advent of high-throughput molecular methods and the increasing availability of genomic analyses, genetics have acquired a firm foothold in public discourse. However, although the proliferation of genetic association studies and ever-expanding library of single-nucleotide polymorphisms have generated some fascinating results, they have thus far fallen short of delivering the anticipated dramatic breakthroughs. In this collection of eight articles, we present a spectrum of efforts aimed at finding more nuanced and meaningful ways of integrating genomic findings into the study of cognitive aging. The articles present examples of Mendelian randomization in the service of investigating difficult-to-manipulate biochemical properties of human participants. Furthermore, in an important step forward, they acknowledge the interactive effects of genes and physiological risk factors on age-related difference and change in cognitive performance, as well as the possibility of modifying the negative effect of genetic variants by lifestyle changes. PsycINFO Database Record (c) 2014 APA, all rights reserved.

A de novo mosaic mutation in SPAST with two novel alternative alleles and chromosomal copy number variant in a boy with spastic paraplegia and autism spectrum disorder.

Science.gov (United States)

Matthews, A M; Tarailo-Graovac, M; Price, E M; Blydt-Hansen, I; Ghani, A; Drögemöller, B I; Robinson, W P; Ross, C J; Wasserman, W W; Siden, H; van Karnebeek, C D

2017-10-01

Here we report a 12 year old male with an extreme presentation of spastic paraplegia along with autism and dysmorphisms. Whole exome sequencing identified a predicted pathogenic pair of missense variants in SPAST at the same chromosomal location, each with a different alternative allele, while a chromosome microarray identified a 1.73 Mb paternally inherited copy gain of 1q21.1q21.2 resulting in a blended phenotype of both Spastic paraplegia 4 and 1q21.1 microduplication syndrome. We believe that the extreme phenotype observed is likely caused by the presence of cells which contain only mutant SPAST, but that the viability of the patient is possible due mosaicism of mutant alleles observed in different proportions across tissues. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

The 5-HTTLPR variant in the serotonin transporter gene modifies degeneration of brain regions important for emotion in behavioral variant frontotemporal dementia

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Jennifer S. Yokoyama

2015-01-01

Full Text Available The serotonin transporter length polymorphism (5-HTTLPR short allele (5-HTTLPR-s has been associated with differential susceptibility for anxiety and depression in multiple psychiatric disorders. 5-HTTLPR-s modifies the serotonergic systems that support emotion and behavioral regulation by reducing gene expression, which slows the reuptake of serotonin, and is associated with distinct morphological and functional effects. Serotonergic systems are also shown to be dysfunctional in behavioral variant frontotemporal dementia (bvFTD, a disease characterized by marked socioemotional dysfunction. However, studies of 5-HTTLPR-s effects in bvFTD have been inconsistent. Our objective was to investigate the patterns of gray matter volume by 5-HTTLPR-s genotype in both healthy older controls and bvFTD patients. We performed voxel-based morphometry of 179 cognitively normal older adults and 24 bvFTD cases to determine brain changes associated with dose (0/1/2 of 5-HTTLPR-s allele. 5-HTTLPR-s frequency did not differ between controls and bvFTD. We found a significant interaction effect whereby carrying more 5-HTTLPR-s alleles in bvFTD was associated with smaller volume in left inferior frontal gyrus (T = 4.86, PFWE = 0.03 and larger volume in right temporal lobe (T = 5.01, PFWE = 0.01. These results suggest that the 5-HTTLPR-s allele differentially influences brain morphology in bvFTD. We propose that patients with bvFTD and 5-HTTLPR-s have altered volumes in regions that support socioemotional behavior, which may be a developmental or disease-related compensation for altered serotonergic activity.

A Deletion Variant of the α2b-Adrenoceptor Modulates the Stress-Induced Shift from "Cognitive" to "Habit" Memory.

Science.gov (United States)

Wirz, Lisa; Wacker, Jan; Felten, Andrea; Reuter, Martin; Schwabe, Lars

2017-02-22

Stress induces a shift from hippocampus-based "cognitive" toward dorsal striatum-based "habitual" learning and memory. This shift is thought to have important implications for stress-related psychopathologies, including post-traumatic stress disorder (PTSD). However, there is large individual variability in the stress-induced bias toward habit memory, and the factors underlying this variability are completely unknown. Here we hypothesized that a functional deletion variant of the gene encoding the α2b-adrenoceptor ( ADRA2B ), which has been linked to emotional memory processes and increased PTSD risk, modulates the stress-induced shift from cognitive toward habit memory. In two independent experimental studies, healthy humans were genotyped for the ADRA2B deletion variant. After a stress or control manipulation, participants completed a dual-solution learning task while electroencephalographic (Study I) or fMRI measurements (Study II) were taken. Carriers compared with noncarriers of the ADRA2B deletion variant exhibited a significantly reduced bias toward habit memory after stress. fMRI results indicated that, whereas noncarriers of the ADRA2B deletion variant showed increased functional connectivity between amygdala and putamen after stress, this increase in connectivity was absent in carriers of the deletion variant, who instead showed overall enhanced connectivity between amygdala and entorhinal cortex. Our results indicate that a common genetic variation of the noradrenergic system modulates the impact of stress on the balance between cognitive and habitual memory systems, most likely via altered amygdala orchestration of these systems. SIGNIFICANCE STATEMENT Stressful events have a powerful effect on human learning and memory. Specifically, accumulating evidence suggests that stress favors more rigid dorsal striatum-dependent habit memory, at the expense of flexible hippocampus-dependent cognitive memory. Although this shift may have important implications

TREM2 Variants in Alzheimer's Disease

Science.gov (United States)

Guerreiro, Rita; Wojtas, Aleksandra; Bras, Jose; Carrasquillo, Minerva; Rogaeva, Ekaterina; Majounie, Elisa; Cruchaga, Carlos; Sassi, Celeste; Kauwe, John S.K.; Younkin, Steven; Hazrati, Lilinaz; Collinge, John; Pocock, Jennifer; Lashley, Tammaryn; Williams, Julie; Lambert, Jean-Charles; Amouyel, Philippe; Goate, Alison; Rademakers, Rosa; Morgan, Kevin; Powell, John; St. George-Hyslop, Peter; Singleton, Andrew; Hardy, John

2013-01-01

BACKGROUND Homozygous loss-of-function mutations in TREM2, encoding the triggering receptor expressed on myeloid cells 2 protein, have previously been associated with an autosomal recessive form of early-onset dementia. METHODS We used genome, exome, and Sanger sequencing to analyze the genetic variability in TREM2 in a series of 1092 patients with Alzheimer's disease and 1107 controls (the discovery set). We then performed a meta-analysis on imputed data for the TREM2 variant rs75932628 (predicted to cause a R47H substitution) from three genomewide association studies of Alzheimer's disease and tested for the association of the variant with disease. We genotyped the R47H variant in an additional 1887 cases and 4061 controls. We then assayed the expression of TREM2 across different regions of the human brain and identified genes that are differentially expressed in a mouse model of Alzheimer's disease and in control mice. RESULTS We found significantly more variants in exon 2 of TREM2 in patients with Alzheimer's disease than in controls in the discovery set (P = 0.02). There were 22 variant alleles in 1092 patients with Alzheimer's disease and 5 variant alleles in 1107 controls (P<0.001). The most commonly associated variant, rs75932628 (encoding R47H), showed highly significant association with Alzheimer's disease (P<0.001). Meta-analysis of rs75932628 genotypes imputed from genomewide association studies confirmed this association (P = 0.002), as did direct genotyping of an additional series of 1887 patients with Alzheimer's disease and 4061 controls (P<0.001). Trem2 expression differed between control mice and a mouse model of Alzheimer's disease. CONCLUSIONS Heterozygous rare variants in TREM2 are associated with a significant increase in the risk of Alzheimer's disease. (Funded by Alzheimer's Research UK and others.) PMID:23150934

Bi-allelic Alterations in AEBP1 Lead to Defective Collagen Assembly and Connective Tissue Structure Resulting in a Variant of Ehlers-Danlos Syndrome.

Science.gov (United States)

Blackburn, Patrick R; Xu, Zhi; Tumelty, Kathleen E; Zhao, Rose W; Monis, William J; Harris, Kimberly G; Gass, Jennifer M; Cousin, Margot A; Boczek, Nicole J; Mitkov, Mario V; Cappel, Mark A; Francomano, Clair A; Parisi, Joseph E; Klee, Eric W; Faqeih, Eissa; Alkuraya, Fowzan S; Layne, Matthew D; McDonnell, Nazli B; Atwal, Paldeep S

2018-04-05

AEBP1 encodes the aortic carboxypeptidase-like protein (ACLP) that associates with collagens in the extracellular matrix (ECM) and has several roles in development, tissue repair, and fibrosis. ACLP is expressed in bone, the vasculature, and dermal tissues and is involved in fibroblast proliferation and mesenchymal stem cell differentiation into collagen-producing cells. Aebp1 -/- mice have abnormal, delayed wound repair correlating with defects in fibroblast proliferation. In this study, we describe four individuals from three unrelated families that presented with a unique constellation of clinical findings including joint laxity, redundant and hyperextensible skin, poor wound healing with abnormal scarring, osteoporosis, and other features reminiscent of Ehlers-Danlos syndrome (EDS). Analysis of skin biopsies revealed decreased dermal collagen with abnormal collagen fibrils that were ragged in appearance. Exome sequencing revealed compound heterozygous variants in AEBP1 (c.1470delC [p.Asn490_Met495delins(40)] and c.1743C>A [p.Cys581 ∗ ]) in the first individual, a homozygous variant (c.1320_1326del [p.Arg440Serfs ∗ 3]) in the second individual, and a homozygous splice site variant (c.1630+1G>A) in two siblings from the third family. We show that ACLP enhances collagen polymerization and binds to several fibrillar collagens via its discoidin domain. These studies support the conclusion that bi-allelic pathogenic variants in AEBP1 are the cause of this autosomal-recessive EDS subtype. Copyright © 2018 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

The Use of Non-Variant Sites to Improve the Clinical Assessment of Whole-Genome Sequence Data.

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Alberto Ferrarini

Full Text Available Genetic testing, which is now a routine part of clinical practice and disease management protocols, is often based on the assessment of small panels of variants or genes. On the other hand, continuous improvements in the speed and per-base costs of sequencing have now made whole exome sequencing (WES and whole genome sequencing (WGS viable strategies for targeted or complete genetic analysis, respectively. Standard WGS/WES data analytical workflows generally rely on calling of sequence variants respect to the reference genome sequence. However, the reference genome sequence contains a large number of sites represented by rare alleles, by known pathogenic alleles and by alleles strongly associated to disease by GWAS. It's thus critical, for clinical applications of WGS and WES, to interpret whether non-variant sites are homozygous for the reference allele or if the corresponding genotype cannot be reliably called. Here we show that an alternative analytical approach based on the analysis of both variant and non-variant sites from WGS data allows to genotype more than 92% of sites corresponding to known SNPs compared to 6% genotyped by standard variant analysis. These include homozygous reference sites of clinical interest, thus leading to a broad and comprehensive characterization of variation necessary to an accurate evaluation of disease risk. Altogether, our findings indicate that characterization of both variant and non-variant clinically informative sites in the genome is necessary to allow an accurate clinical assessment of a personal genome. Finally, we propose a highly efficient extended VCF (eVCF file format which allows to store genotype calls for sites of clinical interest while remaining compatible with current variant interpretation software.

Frequency of the Hemochromatosis Gene (HFE Variants in a Jordanian Arab Population and in Diabetics from the Same Region

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Asem Alkhateeb

2009-01-01

Full Text Available Hereditary HFE-linked hemochromatosis is a frequent recessive disorder among individuals of northern European ancestry. The clinical characteristic of this disease is the gradual accumulation of iron in internal organs, which ultimately may lead to organ damage and death. Three allelic variants of HFE gene have been correlated with hereditary hemochromatosis: C282Y is significantly associated with hereditary hemochromatosis in populations of Celtic origin, H63D and S65C are associated with milder form of iron overload. In this study we performed mutation analysis to identify allele frequency of the three variants of HFE gene in Jordanian Arab population, to assess deviations of these frequencies from those detected elsewhere, and to determine if there is an increased frequency of these variants in a diabetic population (Type 2 diabetes from the same area. DNA was extracted from blood samples of 440 individuals attending King Abdullah University Hospital for ambulatory services. We used polymerase chain reaction (PCR to amplify exons 2 and 4 of the HFE gene then restriction fragment length polymorphism (RFLP method to detect the variants. There were neither homozygous nor heterozygous for C282Y variant. For the H63D variant, 0.68% were homozygous and 21.1% were heterozygous. For the S65C variant, there were no homozygous and 0.23% were heterozygous. Allelic frequencies were, 0%, 11.25%, and 0.11% for C282Y, H63D, and S65C, respectively. Our samples were subdivided into two categories of type 2 diabetic (89 cases and controls (blood donors, 204 cases and compared with regard to the H63D variant. Both groups did not have homozygous H63D variant. H63D heterozygous in diabetics were 23.60% and in blood donor controls 22.55%. Allelic frequency of the mutant H63D allele was 11.80% in diabetics and 11.27% for the blood donor controls. This is the first study to show the frequency of the three hemochromatosis gene variants in Jordan with the interesting

New insights into the history of the C-14010 lactase persistence variant in Eastern and Southern Africa

OpenAIRE

Macholdt, Enrico; Slatkin, Montgomery; Pakendorf, Brigitte; Stoneking, Mark

2014-01-01

Lactase persistence (LP), the ability to digest lactose into adulthood, is strongly associated with the cultural traits of pastoralism and milk-drinking among human populations, and several different genetic variants are known that confer LP. Recent studies of LP variants in Southern African populations, with a focus on Khoisan-speaking groups, found high frequencies of an LP variant (the C-14010 allele) that also occurs in Eastern Africa, and concluded that the C-14010 allele was brought to ...

Neural effects of the CSMD1 genome-wide associated schizophrenia risk variant rs10503253.

LENUS (Irish Health Repository)

Rose, Emma J

2013-09-01

The single nucleotide polymorphism rs10503253 within the CUB and Sushi multiple domains-1 (CSMD1) gene on 8p23.2 has been identified as genome-wide significant for schizophrenia (SZ). This gene is of unknown function but has been implicated in multiple neurodevelopmental disorders that impact upon cognition, leading us to hypothesize that an effect on brain structure and function underlying cognitive processes may be part of the mechanism by which CMSD1 increases illness risk. To test this hypothesis, we investigated this CSMD1 variant in vivo in healthy participants in a magnetic resonance imaging (MRI) study comprised of both fMRI of spatial working memory (N = 50) and a voxel-based morphometry investigation of grey and white matter (WM) volume (N = 150). Analyses of these data indicated that the risk "A" allele was associated with comparatively reduced cortical activations in BA18, that is, middle occipital gyrus and cuneus; posterior brain regions that support maintenance processes during performance of a spatial working memory task. Conversely, there was an absence of significant structural differences in brain volume (i.e., grey or WM). In accordance with previous evidence, these data suggest that CSMD1 may mediate brain function related to cognitive processes (i.e., executive function); with the relatively deleterious effects of the identified "A" risk allele on brain activity possibly constituting part of the mechanism by which CSMD1 increases schizophrenia risk.

Genetic variants associated with altered plasma levels of C-reactive protein are not associated with late-life cognitive ability in four Scottish samples.

Science.gov (United States)

Marioni, Riccardo E; Deary, Ian J; Murray, Gordon D; Lowe, Gordon D O; Rafnsson, Snorri B; Strachan, Mark W J; Luciano, Michelle; Houlihan, Lorna M; Gow, Alan J; Harris, Sarah E; Stewart, Marlene C; Rumley, Ann; Fowkes, F Gerry R; Price, Jackie F

2010-01-01

It is unknown whether the relationship between raised inflammatory biomarker levels and late-life cognitive ability is causal. We explored this issue by testing the association between genetic regulators of plasma C-reactive protein (CRP) and cognition. Data were analysed from four cohorts based in central Scotland (Total N = 4,782). Associations were tested between variants in the CRP gene and both plasma CRP levels and a battery of neuropsychological tests, including a vocabulary-based estimate of peak prior cognitive ability and a general (summary) cognitive factor score, or 'g'. CRP levels were associated with a number of variants in the CRP gene (SNPs), including rs1205, rs1130864, rs1800947, and rs1417938 (P range 4.2e-06 to 0.041). Higher CRP levels were also associated with vocabulary-adjusted cognitive ability, used here to estimate lifetime cognitive change (P range 1.7e-04 to 0.038). After correction for multiple testing and adjustment for age and sex, no statistically significant associations were found between the SNPs and cognition. CRP is unlikely to be a causal determinant of late-life cognitive ability.

Rare and low-frequency coding variants alter human adult height

NARCIS (Netherlands)

Marouli, Eirini; Graff, Mariaelisa; Medina-Gomez, Carolina; Lo, Ken Sin; Wood, Andrew R.; Kjaer, Troels R.; Fine, Rebecca S.; Lu, Yingchang; Schurmann, Claudia; Highland, Heather M.; Rüeger, Sina; Thorleifsson, Gudmar; Justice, Anne E.; Lamparter, David; Stirrups, Kathleen E.; Turcot, Valérie; Young, Kristin L.; Winkler, Thomas W.; Esko, Tõnu; Karaderi, Tugce; Locke, Adam E.; Masca, Nicholas G. D.; Ng, Maggie C. Y.; Mudgal, Poorva; Rivas, Manuel A.; Vedantam, Sailaja; Mahajan, Anubha; Guo, Xiuqing; Abecasis, Goncalo; Aben, Katja K.; Adair, Linda S.; Alam, Dewan S.; Albrecht, Eva; Allin, Kristine H.; Allison, Matthew; Amouyel, Philippe; Appel, Emil V.; Arveiler, Dominique; Asselbergs, Folkert W.; Auer, Paul L.; Balkau, Beverley; Banas, Bernhard; Bang, Lia E.; Benn, Marianne; Bergmann, Sven; Bielak, Lawrence F.; Blüher, Matthias; Boeing, Heiner; Boerwinkle, Eric; Böger, Carsten A.; Bonnycastle, Lori L.; Bork-Jensen, Jette; Bots, Michiel L.; Bottinger, Erwin P.; Bowden, Donald W.; Brandslund, Ivan; Breen, Gerome; Brilliant, Murray H.; Broer, Linda; Burt, Amber A.; Butterworth, Adam S.; Carey, David J.; Caulfield, Mark J.; Chambers, John C.; Chasman, Daniel I.; Chen, Yii-Der Ida; Chowdhury, Rajiv; Christensen, Cramer; Chu, Audrey Y.; Cocca, Massimiliano; Collins, Francis S.; Cook, James P.; Corley, Janie; Galbany, Jordi Corominas; Cox, Amanda J.; Cuellar-Partida, Gabriel; Danesh, John; Davies, Gail; de Bakker, Paul I. W.; de Borst, Gert J.; de Denus, Simon; de Groot, Mark C. H.; de Mutsert, Renée; Deary, Ian J.; Dedoussis, George; Demerath, Ellen W.; den Hollander, Anneke I.; Dennis, Joe G.; Di Angelantonio, Emanuele; Drenos, Fotios; Du, Mengmeng; Dunning, Alison M.; Easton, Douglas F.; Ebeling, Tapani; Edwards, Todd L.; Ellinor, Patrick T.; Elliott, Paul; Evangelou, Evangelos; Farmaki, Aliki-Eleni; Faul, Jessica D.; Feitosa, Mary F.; Feng, Shuang; Ferrannini, Ele; Ferrario, Marco M.; Ferrieres, Jean; Florez, Jose C.; Ford, Ian; Fornage, Myriam; Franks, Paul W.; Frikke-Schmidt, Ruth; Galesloot, Tessel E.; Gan, Wei; Gandin, Ilaria; Gasparini, Paolo; Giedraitis, Vilmantas; Giri, Ayush; Girotto, Giorgia; Gordon, Scott D.; Gordon-Larsen, Penny; Gorski, Mathias; Grarup, Niels; Grove, Megan L.; Gudnason, Vilmundur; Gustafsson, Stefan; Hansen, Torben; Harris, Kathleen Mullan; Harris, Tamara B.; Hattersley, Andrew T.; Hayward, Caroline; He, Liang; Heid, Iris M.; Heikkilä, Kauko; Helgeland, Øyvind; Hernesniemi, Jussi; Hewitt, Alex W.; Hocking, Lynne J.; Hollensted, Mette; Holmen, Oddgeir L.; Hovingh, G. Kees; Howson, Joanna M. M.; Hoyng, Carel B.; Huang, Paul L.; Hveem, Kristian; Ikram, M. Arfan; Ingelsson, Erik; Jackson, Anne U.; Jansson, Jan-Håkan; Jarvik, Gail P.; Jensen, Gorm B.; Jhun, Min A.; Jia, Yucheng; Jiang, Xuejuan; Johansson, Stefan; Jørgensen, Marit E.; Jørgensen, Torben; Jousilahti, Pekka; Jukema, J. Wouter; Kahali, Bratati; Kahn, René S.; Kähönen, Mika; Kamstrup, Pia R.; Kanoni, Stavroula; Kaprio, Jaakko; Karaleftheri, Maria; Kardia, Sharon L. R.; Karpe, Fredrik; Kee, Frank; Keeman, Renske; Kiemeney, Lambertus A.; Kitajima, Hidetoshi; Kluivers, Kirsten B.; Kocher, Thomas; Komulainen, Pirjo; Kontto, Jukka; Kooner, Jaspal S.; Kooperberg, Charles; Kovacs, Peter; Kriebel, Jennifer; Kuivaniemi, Helena; Küry, Sébastien; Kuusisto, Johanna; La Bianca, Martina; Laakso, Markku; Lakka, Timo A.; Lange, Ethan M.; Lange, Leslie A.; Langefeld, Carl D.; Langenberg, Claudia; Larson, Eric B.; Lee, I.-Te; Lehtimäki, Terho; Lewis, Cora E.; Li, Huaixing; Li, Jin; Li-Gao, Ruifang; Lin, Honghuang; Lin, Li-An; Lin, Xu; Lind, Lars; Lindström, Jaana; Linneberg, Allan; Liu, Yeheng; Liu, Yongmei; Lophatananon, Artitaya; Luan, Jian'an; Lubitz, Steven A.; Lyytikäinen, Leo-Pekka; Mackey, David A.; Madden, Pamela A. F.; Manning, Alisa K.; Männistö, Satu; Marenne, Gaëlle; Marten, Jonathan; Martin, Nicholas G.; Mazul, Angela L.; Meidtner, Karina; Metspalu, Andres; Mitchell, Paul; Mohlke, Karen L.; Mook-Kanamori, Dennis O.; Morgan, Anna; Morris, Andrew D.; Morris, Andrew P.; Müller-Nurasyid, Martina; Munroe, Patricia B.; Nalls, Mike A.; Nauck, Matthias; Nelson, Christopher P.; Neville, Matt; Nielsen, Sune F.; Nikus, Kjell; Njølstad, Pål R.; Nordestgaard, Børge G.; Ntalla, Ioanna; O'Connel, Jeffrey R.; Oksa, Heikki; Loohuis, Loes M. Olde; Ophoff, Roel A.; Owen, Katharine R.; Packard, Chris J.; Padmanabhan, Sandosh; Palmer, Colin N. A.; Pasterkamp, Gerard; Patel, Aniruddh P.; Pattie, Alison; Pedersen, Oluf; Peissig, Peggy L.; Peloso, Gina M.; Pennell, Craig E.; Perola, Markus; Perry, James A.; Perry, John R. B.; Person, Thomas N.; Pirie, Ailith; Polasek, Ozren; Posthuma, Danielle; Raitakari, Olli T.; Rasheed, Asif; Rauramaa, Rainer; Reilly, Dermot F.; Reiner, Alex P.; Renström, Frida; Ridker, Paul M.; Rioux, John D.; Robertson, Neil; Robino, Antonietta; Rolandsson, Olov; Rudan, Igor; Ruth, Katherine S.; Saleheen, Danish; Salomaa, Veikko; Samani, Nilesh J.; Sandow, Kevin; Sapkota, Yadav; Sattar, Naveed; Schmidt, Marjanka K.; Schreiner, Pamela J.; Schulze, Matthias B.; Scott, Robert A.; Segura-Lepe, Marcelo P.; Shah, Svati; Sim, Xueling; Sivapalaratnam, Suthesh; Small, Kerrin S.; Smith, Albert Vernon; Smith, Jennifer A.; Southam, Lorraine; Spector, Timothy D.; Speliotes, Elizabeth K.; Starr, John M.; Steinthorsdottir, Valgerdur; Stringham, Heather M.; Stumvoll, Michael; Surendran, Praveen; 't Hart, Leen M.; Tansey, Katherine E.; Tardif, Jean-Claude; Taylor, Kent D.; Teumer, Alexander; Thompson, Deborah J.; Thorsteinsdottir, Unnur; Thuesen, Betina H.; Tönjes, Anke; Tromp, Gerard; Trompet, Stella; Tsafantakis, Emmanouil; Tuomilehto, Jaakko; Tybjaerg-Hansen, Anne; Tyrer, Jonathan P.; Uher, Rudolf; Uitterlinden, André G.; Ulivi, Sheila; van der Laan, Sander W.; van der Leij, Andries R.; van Duijn, Cornelia M.; van Schoor, Natasja M.; van Setten, Jessica; Varbo, Anette; Varga, Tibor V.; Varma, Rohit; Edwards, Digna R. Velez; Vermeulen, Sita H.; Vestergaard, Henrik; Vitart, Veronique; Vogt, Thomas F.; Vozzi, Diego; Walker, Mark; Wang, Feijie; Wang, Carol A.; Wang, Shuai; Wang, Yiqin; Wareham, Nicholas J.; Warren, Helen R.; Wessel, Jennifer; Willems, Sara M.; Wilson, James G.; Witte, Daniel R.; Woods, Michael O.; Wu, Ying; Yaghootkar, Hanieh; Yao, Jie; Yao, Pang; Yerges-Armstrong, Laura M.; Young, Robin; Zeggini, Eleftheria; Zhan, Xiaowei; Zhang, Weihua; Zhao, Jing Hua; Zhao, Wei; Zheng, He; Zhou, Wei; Rotter, Jerome I.; Boehnke, Michael; Kathiresan, Sekar; McCarthy, Mark I.; Willer, Cristen J.; Stefansson, Kari; Borecki, Ingrid B.; Liu, Dajiang J.; North, Kari E.; Heard-Costa, Nancy L.; Pers, Tune H.; Lindgren, Cecilia M.; Oxvig, Claus; Kutalik, Zoltán; Rivadeneira, Fernando; Loos, Ruth J. F.; Frayling, Timothy M.; Hirschhorn, Joel N.; Deloukas, Panos; Lettre, Guillaume

2017-01-01

Height is a highly heritable, classic polygenic trait with approximately 700 common associated variants identified through genome-wide association studies so far. Here, we report 83 height-associated coding variants with lower minor-allele frequencies (in the range of 0.1-4.8%) and effects of up to

Frequency of the allelic variant c.1150T > C in exon 10 of the fibroblast growth factor receptor 3 (FGFR3 gene is not increased in patients with pathogenic mutations and related chondrodysplasia phenotypes

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Thatiane Yoshie Kanazawa

2014-12-01

Full Text Available Mutations in the FGFR3 gene cause the phenotypic spectrum of FGFR3 chondrodysplasias ranging from lethal forms to the milder phenotype seen in hypochondroplasia (Hch. The p.N540K mutation in the FGFR3 gene occurs in ~70% of individuals with Hch, and nearly 30% of individuals with the Hch phenotype have no mutations in the FGFR3, which suggests genetic heterogeneity. The identification of a severe case of Hch associated with the typical mutation c.1620C > A and the occurrence of a c.1150T > C change that resulted in a p.F384L in exon 10, together with the suspicion that this second change could be a modulator of the phenotype, prompted us to investigate this hypothesis in a cohort of patients. An analysis of 48 patients with FGFR3 chondrodysplasia phenotypes and 330 healthy (control individuals revealed no significant difference in the frequency of the C allele at the c.1150 position (p = 0.34. One patient carrying the combination `pathogenic mutation plus the allelic variant c.1150T > C' had a typical achondroplasia (Ach phenotype. In addition, three other patients with atypical phenotypes showed no association with the allelic variant. Together, these results do not support the hypothesis of a modulatory role for the c.1150T > C change in the FGFR3 gene.

Selected vitamin D metabolic gene variants and risk for autism spectrum disorder in the CHARGE Study.

Science.gov (United States)

Schmidt, Rebecca J; Hansen, Robin L; Hartiala, Jaana; Allayee, Hooman; Sconberg, Jaime L; Schmidt, Linda C; Volk, Heather E; Tassone, Flora

2015-08-01

Vitamin D is essential for proper neurodevelopment and cognitive and behavioral function. We examined associations between autism spectrum disorder (ASD) and common, functional polymorphisms in vitamin D pathways. Children aged 24-60 months enrolled from 2003 to 2009 in the population-based CHARGE case-control study were evaluated clinically and confirmed to have ASD (n=474) or typical development (TD, n=281). Maternal, paternal, and child DNA samples for 384 (81%) families of children with ASD and 234 (83%) families of TD children were genotyped for: TaqI, BsmI, FokI, and Cdx2 in the vitamin D receptor (VDR) gene, and CYP27B1 rs4646536, GC rs4588, and CYP2R1 rs10741657. Case-control logistic regression, family-based log-linear, and hybrid log-linear analyses were conducted to produce risk estimates and 95% confidence intervals (CI) for each allelic variant. Paternal VDR TaqI homozygous variant genotype was significantly associated with ASD in case-control analysis (odds ratio [OR] [CI]: 6.3 [1.9-20.7]) and there was a trend towards increased risk associated with VDR BsmI (OR [CI]: 4.7 [1.6-13.4]). Log-linear triad analyses detected parental imprinting, with greater effects of paternally-derived VDR alleles. Child GC AA-genotype/A-allele was associated with ASD in log-linear and ETDT analyses. A significant association between decreased ASD risk and child CYP2R1 AA-genotype was found in hybrid log-linear analysis. There were limitations of low statistical power for less common alleles due to missing paternal genotypes. This study provides preliminary evidence that paternal and child vitamin D metabolism could play a role in the etiology of ASD; further research in larger study populations is warranted. Copyright © 2015. Published by Elsevier Ireland Ltd.

Study on the IFNL4 gene ss469415590 variant in Ukrainian population

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Kucherenko A. M.

2014-09-01

Full Text Available Aim. To determine genotype and allele disribution for the IFNL4 gene ss469415590 and examine it for linkage with the IL28B gene rs12979860 in Ukrainian population. Methods. The studied group consisted of 100 unrelated donors of Eastern European origin representing the population of Ukraine. Genotyping for the IFNL4 gene ss469415590 was performed using the amplification-refractory mutation system PCR. Genotyping for the IL28B gene rs12979860 was performed by the PCR-based restriction fragment length polymorphism assay. Results. Genotype frequencies for both studied variants showed no significant deviation from those expected according to Hardy-Weinberg equilibrium. Allelic distribution for ss469415590 was: TT – 0.665, G – 0.335. Allelic frequencies of rs12979860 were: C – 0.655, T – 0.345. The results of likelihood ratio test indicated a linkage disequilibrium between the studied variants (p > 0.0001, the major alleles ss469415590 TT and rs12979860 C were in phase. The genetic structure of Ukrainian population in terms of two studied polymorphic variants is similar to the European population presented in the «1000 genomes» project. Conclusions. Considering a tight linkage revealed in Ukrainian population between the ss469415590 variant and rs12979860, a crucial genetic marker of chronic hepatitis C treatment efficiency, this polymorphism might be a promising target for further investigation as a pharmacogenetic marker.

Cardiovascular Pharmacogenomics and Cognitive Function in Patients with Schizophrenia.

Science.gov (United States)

Ward, Kristen M; Kraal, A Zarina; Flowers, Stephanie A; Ellingrod, Vicki L

2017-09-01

The authors sought to examine the impact of multiple risk alleles for cognitive dysfunction and cardiovascular disease risk on cognitive function and to determine if these relationships varied by cognitive reserve (CR) or concomitant medication use in patients with schizophrenia. They conducted a cross-sectional study in ambulatory mental health centers. A total of 122 adults with a schizophrenia spectrum diagnosis who were maintained on a stable antipsychotic regimen for at least 6 months before study enrollment were included. Patients were divided into three CR groups based on years of formal education: no high school completion or equivalent (low-education group [18 patients]), completion of high school or equivalent (moderate-education group [36 patients], or any degree of post-high school education (high-education group [68 patients]). The following pharmacogenomic variants were genotyped for each patient: AGT M268T (rs699), ACE insertion/deletion (or ACE I/D, rs1799752), and APOE ε2, ε3, and ε4 (rs429358 and rs7412). Risk allele carrier status (identified per gene as AGT M268 T carriers, ACE D carriers, and APOE ε4 carriers) was not significantly different among CR groups. The Brief Assessment of Cognition in Schizophrenia (BACS) scale was used to assess cognitive function. The mean ± SD patient age was 43.9 ± 11.6 years. Cardiovascular risk factors such as hypertension and hyperlipidemia diagnoses, and use of antihypertensive and lipid-lowering agents, did not significantly differ among CR groups. Mixed modeling revealed that risk allele carrier status was significantly associated with lower verbal memory scores for ACE D and APOE ε4 carriers, but AGT T carrier status was significantly associated with higher verbal memory scores (p=0.0188, p=0.0055, and p=0.0058, respectively). These results were only significant in the low-education group. In addition, medication-gene interactions were not significant predictors of BACS scores. ACE D and APOE ε4

A population-specific uncommon variant in GRIN3A associated with schizophrenia.

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Takata, Atsushi; Iwayama, Yoshimi; Fukuo, Yasuhisa; Ikeda, Masashi; Okochi, Tomo; Maekawa, Motoko; Toyota, Tomoko; Yamada, Kazuo; Hattori, Eiji; Ohnishi, Tetsuo; Toyoshima, Manabu; Ujike, Hiroshi; Inada, Toshiya; Kunugi, Hiroshi; Ozaki, Norio; Nanko, Shinichiro; Nakamura, Kazuhiko; Mori, Norio; Kanba, Shigenobu; Iwata, Nakao; Kato, Tadafumi; Yoshikawa, Takeo

2013-03-15

Genome-wide association studies have successfully identified several common variants showing robust association with schizophrenia. However, individually, these variants only produce a weak effect. To identify genetic variants with larger effect sizes, increasing attention is now being paid to uncommon and rare variants. From the 1000 Genomes Project data, we selected 47 candidate single nucleotide variants (SNVs), which were: 1) uncommon (minor allele frequency way to discover risk variants with larger effects. Copyright © 2013 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Allele-Specific Alternative mRNA processing (ASARP) | Informatics Technology for Cancer Research (ITCR)

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A software pipeline for prediction of allele-specific alternative RNA processing events using single RNA-seq data. The current version focuses on prediction of alternative splicing and alternative polyadenylation modulated by genetic variants.

Association of fat mass and obesity-associated gene variant with lifestyle factors and body fat in Indian Children

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Lavanya S Parthasarthy

2017-01-01

Full Text Available Context: Common intronic variants of the fat mass and obesity-associated (FTO gene have been associated with obesity-related traits in humans. Aims: (1 The aim of this study is to study the distribution of FTO gene variants across different body mass index (BMI categories and (2 to explore the association between FTO gene variants and lifestyle factors in obese and normal weight Indian children. Subjects and Methods: Fifty-six children (26 boys, mean age 10.3 ± 2.2 years were studied. Height, weight, and waist and hip circumference were measured. Physical activity (questionnaire and food intake (food frequency questionnaire were assessed. Body fat percentage (%BF was measured by dual-energy X-ray absorptiometry. FTO allelic variants at rs9939609 site were detected by SYBR Green Amplification Refractory Mutation System real-time polymerase chain reaction using allele-specific primers. Generalized linear model was used to investigate the simultaneous influence of genetic and lifestyle factors on %BF. Results: Mean height, weight, and BMI of normal and obese children were 130.6 ± 7.1 versus 143.2 ± 15.6, 24.0 ± 5.2 versus 53.1 ± 15.8, and 13.9 ± 2.1 versus 25.3 ± 3.2, respectively. The frequency of AA allele was 57% among obese children and 35% in normal weight children. Children with the AA allele who were obese had least physical activity, whereas children with AT allele and obesity had the highest intake of calories when compared to children who had AT allele and were normal. %BF was positively associated with AA alleles and junk food intake and negatively with healthy food intake and moderate physical activity. Conclusions: Healthy lifestyle with high physical activity and diet low in calories and fat may help in modifying the risk imposed by FTO variants in children.

Deceased-Donor Apolipoprotein L1 Renal-Risk Variants Have Minimal Effects on Liver Transplant Outcomes.

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Casey R Dorr

Full Text Available Apolipoprotein L1 gene (APOL1 G1 and G2 renal-risk variants, common in populations with recent African ancestry, are strongly associated with non-diabetic nephropathy, end-stage kidney disease, and shorter allograft survival in deceased-donor kidneys (autosomal recessive inheritance. Circulating APOL1 protein is synthesized primarily in the liver and hydrodynamic gene delivery of APOL1 G1 and G2 risk variants has caused hepatic necrosis in a murine model.To evaluate the impact of these variants in liver transplantation, this multicenter study investigated the association of APOL1 G1 and G2 alleles in deceased African American liver donors with allograft survival. Transplant recipients were followed for liver allograft survival using data from the Scientific Registry of Transplant Recipients.Of the 639 liver donors evaluated, 247 had no APOL1 risk allele, 300 had 1 risk allele, and 92 had 2 risk alleles. Graft failure assessed at 15 days, 6 months, 1 year and total was not significantly associated with donor APOL1 genotype (p-values = 0.25, 0.19, 0.67 and 0.89, respectively.In contrast to kidney transplantation, deceased-donor APOL1 G1 and G2 risk variants do not significantly impact outcomes in liver transplantation.

Distribution of HIV-1 resistance-conferring polymorphic alleles SDF ...

Indian Academy of Sciences (India)

Polymorphic allelic variants of chemokine receptors CCR2 and CCR5, as well as of stromal-derived factor-1 SDF-1, the ligand for the chemokine receptor CXCR4, are known to have protective effects against HIV-1 infection and to be involved with delay in disease progression. We have studied the DNA polymorphisms at ...

Frequency of CCR5Δ32 allele in healthy Bosniak population.

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Grażyna Adler

2014-08-01

Full Text Available Recent evidence has demonstrated the role of CCR5Δ32 in a variety of human diseases: from infectious and inflammatory diseases to cancer. Several studies have confirmed that genetic variants in chemokine receptor CCR5 gene are correlated with susceptibility and resistance to HIV infection. A 32-nucleotide deletion within the CCR5 reading frame is associated with decreased susceptibility to HIV acquisition and a slower progression to AIDS. Mean frequency of CCR5Δ32 allele in Europe is approximately 10%. The highest allele frequency is observed among Nordic populations (about 12% and lower in the regions of Southeast Mediterranean (about 5%. Although the frequency of CCR5Δ32 was determined in numerous European populations, there is a lack of studies on this variant in the Bosnia and Hercegovina population. Therefore, the aim of our study was to assess the frequency of CCR5Δ32 allele in the cohort of Bosniaks and compare the results with European reports. CCR5Δ32 was detected by sequence-specific PCR in a sample of 100 healthy subjects from Bosnia and Herzegovina (DNA collected 2011-2013.  Mean age of the cohort being 58.8 (±10.7 years, with 82% of women. We identified 17 heterozygotes and one mutant homozygote in study group, with mean ∆32 allele frequency of 9.5%. CCR5∆32 allele frequency among Bosniaks is comparable to that found in Caucasian populations and follows the pattern of the north-southern gradient observed for Europe. Further studies on larger cohorts with adequate female-to-male ratio are necessary. 

Predominance of N-acetyl transferase 2 slow acetylator alleles in ...

African Journals Online (AJOL)

Student

The human N-acetyltransferase II (NAT2) gene may vary between individuals resulting in variability in the incidence of adverse drug reactions. We set out in this adhoc analysis to determine the distribution of allele frequencies of NAT2 gene variants among children less than ten years treated with artemisinin-based.

Glucose impairment and ghrelin gene variants are associated to cognitive dysfunction.

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Mora, M; Mansego, M L; Serra-Prat, M; Palomera, E; Boquet, X; Chaves, J F; Puig-Domingo, M

2014-04-01

Cognitive state and brain volume have been related to body mass index, abdominal fat, waist-hip ratio, components of metabolic syndrome (MS) and ghrelin. Genetic variations within the ghrelin gene have been recently associated to MS. The aim of our study was to investigate cognitive state by Mini-Mental State Examination (MMSE) in relation to MS components (ATP-III criteria) and ghrelin gene polymorphisms in dwelling individuals aged ≥70. 280 subjects (137 men/143 women, age 77.03 ± 5.92) from the Mataró Ageing Study were included. Individuals were phenotypically characterized by anthropometric variables, lipids, glucose, blood pressure and MMSE. SNPs -501AC (rs26802), -994CT (rs26312), -604GA (rs27647), M72L (rs696217) and L90G (rs4684677) of the ghrelin gene were studied. Genotypes were determined by polymerase chain reaction and SNapshot minisequencing. 22.1 % had MMSE Ghrelin SNPs were associated to MMSE: M72L C/A genotype showed lower score than C/C (p = 0.032, after adjusting for confounders 0.049); L90G A/T genotype showed lower score than A/A (p = 0.054, after adjusting 0.005). MMSE Ghrelin gene variant influence cognitive function in old dwelling individuals participating in the Mataró Ageing Study.

Somatic cancer variant curation and harmonization through consensus minimum variant level data

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Deborah I. Ritter

2016-11-01

Full Text Available Abstract Background To truly achieve personalized medicine in oncology, it is critical to catalog and curate cancer sequence variants for their clinical relevance. The Somatic Working Group (WG of the Clinical Genome Resource (ClinGen, in cooperation with ClinVar and multiple cancer variant curation stakeholders, has developed a consensus set of minimal variant level data (MVLD. MVLD is a framework of standardized data elements to curate cancer variants for clinical utility. With implementation of MVLD standards, and in a working partnership with ClinVar, we aim to streamline the somatic variant curation efforts in the community and reduce redundancy and time burden for the interpretation of cancer variants in clinical practice. Methods We developed MVLD through a consensus approach by i reviewing clinical actionability interpretations from institutions participating in the WG, ii conducting extensive literature search of clinical somatic interpretation schemas, and iii survey of cancer variant web portals. A forthcoming guideline on cancer variant interpretation, from the Association of Molecular Pathology (AMP, can be incorporated into MVLD. Results Along with harmonizing standardized terminology for allele interpretive and descriptive fields that are collected by many databases, the MVLD includes unique fields for cancer variants such as Biomarker Class, Therapeutic Context and Effect. In addition, MVLD includes recommendations for controlled semantics and ontologies. The Somatic WG is collaborating with ClinVar to evaluate MVLD use for somatic variant submissions. ClinVar is an open and centralized repository where sequencing laboratories can report summary-level variant data with clinical significance, and ClinVar accepts cancer variant data. Conclusions We expect the use of the MVLD to streamline clinical interpretation of cancer variants, enhance interoperability among multiple redundant curation efforts, and increase submission of

Association of COMT and PRODH gene variants with intelligence quotient (IQ) and executive functions in 22q11.2DS subjects.

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Carmel, Miri; Zarchi, Omer; Michaelovsky, Elena; Frisch, Amos; Patya, Miriam; Green, Tamar; Gothelf, Doron; Weizman, Abraham

2014-09-01

The 22q11.2 deletion syndrome (22q11.2DS) carries the highest genetic risk factor for the development of schizophrenia. We investigated the association of genetic variants in two schizophrenia candidate genes with executive function (EF) and IQ in 22q11.2DS individuals. Ninety two individuals with 22q11.2 deletion were studied for the genetic association between COMT and PRODH variants and EF and IQ. Subjects were divided into children (under 12 years old), adolescents (between 12 and 18 years old) and adults (older than 18 years), and genotyped for the COMT Val158Met (rs4680) and PRODH Arg185Trp (rs4819756) polymorphisms. The participants underwent psychiatric evaluation and EF assessment. Our main finding is a significant influence of the COMT Val158Met polymorphism on both IQ and EF performance. Specifically, 22q11.2DS subjects with Met allele displayed higher IQ scores in all age groups compared to Val carriers, reaching significance in both adolescents and adults. The Met allele carriers performed better than Val carriers in EF tasks, being statistically significant in the adult group. PRODH Arg185Trp variant did not affect IQ or EF in our 22q11.2DS cohort. In conclusion, functional COMT variant, but not PRODH, affects IQ and EF in 22q11.2DS subjects during neurodevelopment with a maximal effect at adulthood. Future studies should monitor the cognitive performance of the same individuals from childhood to old age. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assessment of allelic diversity in intron-containing Mal d 1 genes and their association to apple allergenicity

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Bolhaar Suzanne THP

2008-11-01

Full Text Available Abstract Background Mal d 1 is a major apple allergen causing food allergic symptoms of the oral allergy syndrome (OAS in birch-pollen sensitised patients. The Mal d 1 gene family is known to have at least 7 intron-containing and 11 intronless members that have been mapped in clusters on three linkage groups. In this study, the allelic diversity of the seven intron-containing Mal d 1 genes was assessed among a set of apple cultivars by sequencing or indirectly through pedigree genotyping. Protein variant constitutions were subsequently compared with Skin Prick Test (SPT responses to study the association of deduced protein variants with allergenicity in a set of 14 cultivars. Results From the seven intron-containing Mal d 1 genes investigated, Mal d 1.01 and Mal d 1.02 were highly conserved, as nine out of ten cultivars coded for the same protein variant, while only one cultivar coded for a second variant. Mal d 1.04, Mal d 1.05 and Mal d 1.06 A, B and C were more variable, coding for three to six different protein variants. Comparison of Mal d 1 allelic composition between the high-allergenic cultivar Golden Delicious and the low-allergenic cultivars Santana and Priscilla, which are linked in pedigree, showed an association between the protein variants coded by the Mal d 1.04 and -1.06A genes (both located on linkage group 16 with allergenicity. This association was confirmed in 10 other cultivars. In addition, Mal d 1.06A allele dosage effects associated with the degree of allergenicity based on prick to prick testing. Conversely, no associations were observed for the protein variants coded by the Mal d 1.01 (on linkage group 13, -1.02, -1.06B, -1.06C genes (all on linkage group 16, nor by the Mal d 1.05 gene (on linkage group 6. Conclusion Protein variant compositions of Mal d 1.04 and -1.06A and, in case of Mal d 1.06A, allele doses are associated with the differences in allergenicity among fourteen apple cultivars. This information

Comparison of Direct Sequencing, Real-Time PCR-High Resolution Melt (PCR-HRM) and PCR-Restriction Fragment Length Polymorphism (PCR-RFLP) Analysis for Genotyping of Common Thiopurine Intolerant Variant Alleles NUDT15 c.415C>T and TPMT c.719A>G (TPMT*3C).

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Fong, Wai-Ying; Ho, Chi-Chun; Poon, Wing-Tat

2017-05-12

Thiopurine intolerance and treatment-related toxicity, such as fatal myelosuppression, is related to non-function genetic variants encoding thiopurine S-methyltransferase (TPMT) and Nudix hydrolase 15 (NUDT15). Genetic testing of the common variants NUDT15:NM_018283.2:c.415C>T (Arg139Cys, dbSNP rs116855232 T allele) and TPMT: NM_000367.4:c.719A>G (TPMT*3C, dbSNP rs1142345 G allele) in East Asians including Chinese can potentially prevent treatment-related complications. Two complementary genotyping approaches, real-time PCR-high resolution melt (PCR-HRM) and PCR-restriction fragment length morphism (PCR-RFLP) analysis were evaluated using conventional PCR and Sanger sequencing genotyping as the gold standard. Sixty patient samples were tested, revealing seven patients (11.7%) heterozygous for NUDT15 c.415C>T, one patient homozygous for the variant and one patient heterozygous for the TPMT*3C non-function allele. No patient was found to harbor both variants. In total, nine out of 60 (15%) patients tested had genotypic evidence of thiopurine intolerance, which may require dosage adjustment or alternative medication should they be started on azathioprine, mercaptopurine or thioguanine. The two newly developed assays were more efficient and showed complete concordance (60/60, 100%) compared to the Sanger sequencing results. Accurate and cost-effective genotyping assays by real-time PCR-HRM and PCR-RFLP for NUDT15 c.415C>T and TPMT*3C were successfully developed. Further studies may establish their roles in genotype-informed clinical decision-making in the prevention of morbidity and mortality due to thiopurine intolerance.

Common Variants in CLDN2 and MORC4 Genes Confer Disease Susceptibility in Patients with Chronic Pancreatitis.

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Anil K Giri

Full Text Available A recent genome-wide association study (GWAS identified association with variants in X-linked CLDN2 and MORC4, and PRSS1-PRSS2 loci with chronic pancreatitis (CP in North American patients of European ancestry. We selected 9 variants from the reported GWAS and replicated the association with CP in Indian patients by genotyping 1807 unrelated Indians of Indo-European ethnicity, including 519 patients with CP and 1288 controls. The etiology of CP was idiopathic in 83.62% and alcoholic in 16.38% of 519 patients. Our study confirmed a significant association of 2 variants in CLDN2 gene (rs4409525-OR 1.71, P = 1.38 x 10-09; rs12008279-OR 1.56, P = 1.53 x 10-04 and 2 variants in MORC4 gene (rs12688220-OR 1.72, P = 9.20 x 10-09; rs6622126-OR 1.75, P = 4.04x10-05 in Indian patients with CP. We also found significant association at PRSS1-PRSS2 locus (OR 0.60; P = 9.92 x 10-06 and SAMD12-TNFRSF11B (OR 0.49, 95% CI [0.31-0.78], P = 0.0027. A variant in the gene MORC4 (rs12688220 showed significant interaction with alcohol (OR for homozygous and heterozygous risk allele -14.62 and 1.51 respectively, P = 0.0068 suggesting gene-environment interaction. A combined analysis of the genes CLDN2 and MORC4 based on an effective risk allele score revealed a higher percentage of individuals homozygous for the risk allele in CP cases with 5.09 fold enhanced risk in individuals with 7 or more effective risk alleles compared with individuals with 3 or less risk alleles (P = 1.88 x 10-14. Genetic variants in CLDN2 and MORC4 genes were associated with CP in Indian patients.

Temporal expression profiling identifies pathways mediating effect of causal variant on phenotype.

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Saumya Gupta

2015-06-01

Full Text Available Even with identification of multiple causal genetic variants for common human diseases, understanding the molecular processes mediating the causal variants' effect on the disease remains a challenge. This understanding is crucial for the development of therapeutic strategies to prevent and treat disease. While static profiling of gene expression is primarily used to get insights into the biological bases of diseases, it makes differentiating the causative from the correlative effects difficult, as the dynamics of the underlying biological processes are not monitored. Using yeast as a model, we studied genome-wide gene expression dynamics in the presence of a causal variant as the sole genetic determinant, and performed allele-specific functional validation to delineate the causal effects of the genetic variant on the phenotype. Here, we characterized the precise genetic effects of a functional MKT1 allelic variant in sporulation efficiency variation. A mathematical model describing meiotic landmark events and conditional activation of MKT1 expression during sporulation specified an early meiotic role of this variant. By analyzing the early meiotic genome-wide transcriptional response, we demonstrate an MKT1-dependent role of novel modulators, namely, RTG1/3, regulators of mitochondrial retrograde signaling, and DAL82, regulator of nitrogen starvation, in additively effecting sporulation efficiency. In the presence of functional MKT1 allele, better respiration during early sporulation was observed, which was dependent on the mitochondrial retrograde regulator, RTG3. Furthermore, our approach showed that MKT1 contributes to sporulation independent of Puf3, an RNA-binding protein that steady-state transcription profiling studies have suggested to mediate MKT1-pleiotropic effects during mitotic growth. These results uncover interesting regulatory links between meiosis and mitochondrial retrograde signaling. In this study, we highlight the advantage

Protein variants in Hiroshima and Nagasaki: tales of two cities.

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Neel, J V; Satoh, C; Smouse, P; Asakawa, J; Takahashi, N; Goriki, K; Fujita, M; Kageoka, T; Hazama, R

1988-12-01

The results of 1,465,423 allele product determinations based on blood samples from Hiroshima and Nagasaki, involving 30 different proteins representing 32 different gene products, are analyzed in a variety of ways, with the following conclusions: (1) Sibships and their parents are included in the sample. Our analysis reveals that statistical procedures designed to reduce the sample to equivalent independent genomes do not in population comparisons compensate for the familial cluster effect of rare variants. Accordingly, the data set was reduced to one representative of each sibship (937,427 allele products). (2) Both chi 2-type contrasts and a genetic distance measure (delta) reveal that rare variants (P less than .01) are collectively as effective as polymorphisms in establishing genetic differences between the two cities. (3) We suggest that rare variants that individually exhibit significant intercity differences are probably the legacy of tribal private polymorphisms that occurred during prehistoric times. (4) Despite the great differences in the known histories of the two cities, both the overall frequency of rare variants and the number of different rare variants are essentially identical in the two cities. (5) The well-known differences in locus variability are confirmed, now after adjustment for sample size differences for the various locus products; in this large series we failed to detect variants at only three of 29 loci for which sample size exceeded 23,000. (6) The number of alleles identified per locus correlates positively with subunit molecular weight. (7) Loci supporting genetic polymorphisms are characterized by more rare variants than are loci at which polymorphisms were not encountered. (8) Loci whose products do not appear to be essential for health support more variants than do loci the absence of whose product is detrimental to health. (9) There is a striking excess of rare variants over the expectation under the neutral mutation

Evidence of still-ongoing convergence evolution of the lactase persistence T_-13910 alleles in humans

DEFF Research Database (Denmark)

Enattah, Nabil Sabri; Trudeau, Aimee; Pimenoff, Ville

2007-01-01

A single-nucleotide variant, C/T(-13910), located 14 kb upstream of the lactase gene (LCT), has been shown to be completely correlated with lactase persistence (LP) in northern Europeans. Here, we analyzed the background of the alleles carrying the critical variant in 1,611 DNA samples from 37 po...

Effect of sequence variants on variance in glucose levels predicts type 2 diabetes risk and accounts for heritability.

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Ivarsdottir, Erna V; Steinthorsdottir, Valgerdur; Daneshpour, Maryam S; Thorleifsson, Gudmar; Sulem, Patrick; Holm, Hilma; Sigurdsson, Snaevar; Hreidarsson, Astradur B; Sigurdsson, Gunnar; Bjarnason, Ragnar; Thorsson, Arni V; Benediktsson, Rafn; Eyjolfsson, Gudmundur; Sigurdardottir, Olof; Olafsson, Isleifur; Zeinali, Sirous; Azizi, Fereidoun; Thorsteinsdottir, Unnur; Gudbjartsson, Daniel F; Stefansson, Kari

2017-09-01

Sequence variants that affect mean fasting glucose levels do not necessarily affect risk for type 2 diabetes (T2D). We assessed the effects of 36 reported glucose-associated sequence variants on between- and within-subject variance in fasting glucose levels in 69,142 Icelanders. The variant in TCF7L2 that increases fasting glucose levels increases between-subject variance (5.7% per allele, P = 4.2 × 10 -10 ), whereas variants in GCK and G6PC2 that increase fasting glucose levels decrease between-subject variance (7.5% per allele, P = 4.9 × 10 -11 and 7.3% per allele, P = 7.5 × 10 -18 , respectively). Variants that increase mean and between-subject variance in fasting glucose levels tend to increase T2D risk, whereas those that increase the mean but reduce variance do not (r 2 = 0.61). The variants that increase between-subject variance increase fasting glucose heritability estimates. Intuitively, our results show that increasing the mean and variance of glucose levels is more likely to cause pathologically high glucose levels than increase in the mean offset by a decrease in variance.

New insights into the history of the C-14010 lactase persistence variant in Eastern and Southern Africa.

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Macholdt, Enrico; Slatkin, Montgomery; Pakendorf, Brigitte; Stoneking, Mark

2015-04-01

Lactase persistence (LP), the ability to digest lactose into adulthood, is strongly associated with the cultural traits of pastoralism and milk-drinking among human populations, and several different genetic variants are known that confer LP. Recent studies of LP variants in Southern African populations, with a focus on Khoisan-speaking groups, found high frequencies of an LP variant (the C-14010 allele) that also occurs in Eastern Africa, and concluded that the C-14010 allele was brought to Southern Africa via a migration of pastoralists from Eastern Africa. However, this conclusion was based on indirect evidence; to date no study has jointly analyzed data on the C-14010 allele from both Southern African Khoisan-speaking groups and Eastern Africa. Here, we combine and analyze published data on the C-14010 allele in Southern and Eastern African populations, consisting of haplotypes with the C-14010 allele and four closely-linked short tandem repeat loci. Our results provide direct evidence for the previously-hypothesized Eastern African origin of the C-14010 allele in Southern African Khoisan-speaking groups. In addition, we find evidence for a separate introduction of the C-14010 allele into the Bantu-speaking Xhosa. The estimated selection intensity on the C-14010 allele in Eastern Africa is lower than that in Southern Africa, which suggests that in Eastern Africa the dietary changes conferring the fitness advantage associated with LP occurred some time after the origin of the C-14010 allele. Conversely, in Southern Africa the fitness advantage was present when the allele was introduced, as would be expected if pastoralism was introduced concomitantly. © 2014 Wiley Periodicals, Inc.

Use of allele-specific FAIRE to determine functional regulatory polymorphism using large-scale genotyping arrays.

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Andrew J P Smith

Full Text Available Following the widespread use of genome-wide association studies (GWAS, focus is turning towards identification of causal variants rather than simply genetic markers of diseases and traits. As a step towards a high-throughput method to identify genome-wide, non-coding, functional regulatory variants, we describe the technique of allele-specific FAIRE, utilising large-scale genotyping technology (FAIRE-gen to determine allelic effects on chromatin accessibility and regulatory potential. FAIRE-gen was explored using lymphoblastoid cells and the 50,000 SNP Illumina CVD BeadChip. The technique identified an allele-specific regulatory polymorphism within NR1H3 (coding for LXR-α, rs7120118, coinciding with a previously GWAS-identified SNP for HDL-C levels. This finding was confirmed using FAIRE-gen with the 200,000 SNP Illumina Metabochip and verified with the established method of TaqMan allelic discrimination. Examination of this SNP in two prospective Caucasian cohorts comprising 15,000 individuals confirmed the association with HDL-C levels (combined beta = 0.016; p = 0.0006, and analysis of gene expression identified an allelic association with LXR-α expression in heart tissue. Using increasingly comprehensive genotyping chips and distinct tissues for examination, FAIRE-gen has the potential to aid the identification of many causal SNPs associated with disease from GWAS.

Exome Genotyping Identifies Pleiotropic Variants Associated with Red Blood Cell Traits

DEFF Research Database (Denmark)

Chami, Nathalie; Chen, Ming-Huei; Slater, Andrew J

2016-01-01

array. After conditional analyses and replication in 27,480 independent individuals, we identified 16 new RBC variants. We found low-frequency missense variants in MAP1A (rs55707100, minor allele frequency [MAF] = 3.3%, p = 2 × 10(-10) for hemoglobin [HGB]) and HNF4A (rs1800961, MAF = 2.4%, p

Mining the Human Phenome Using Allelic Scores That Index Biological Intermediates

DEFF Research Database (Denmark)

Evans, David M; Brion, Marie Jo A; Paternoster, Lavinia

2013-01-01

It is common practice in genome-wide association studies (GWAS) to focus on the relationship between disease risk and genetic variants one marker at a time. When relevant genes are identified it is often possible to implicate biological intermediates and pathways likely to be involved in disease...... aetiology. However, single genetic variants typically explain small amounts of disease risk. Our idea is to construct allelic scores that explain greater proportions of the variance in biological intermediates, and subsequently use these scores to data mine GWAS. To investigate the approach's properties, we...

A NOS1 variant implicated in cognitive performance influences evoked neural responses during a high density EEG study of early visual perception.

LENUS (Irish Health Repository)

O'Donoghue, Therese

2012-05-01

The nitric oxide synthasase-1 gene (NOS1) has been implicated in mental disorders including schizophrenia and variation in cognition. The NOS1 variant rs6490121 identified in a genome wide association study of schizophrenia has recently been associated with variation in general intelligence and working memory in both patients and healthy participants. Whether this variant is also associated with variation in early sensory processing remains unclear.

A geometric framework for evaluating rare variant tests of association.

Science.gov (United States)

Liu, Keli; Fast, Shannon; Zawistowski, Matthew; Tintle, Nathan L

2013-05-01

The wave of next-generation sequencing data has arrived. However, many questions still remain about how to best analyze sequence data, particularly the contribution of rare genetic variants to human disease. Numerous statistical methods have been proposed to aggregate association signals across multiple rare variant sites in an effort to increase statistical power; however, the precise relation between the tests is often not well understood. We present a geometric representation for rare variant data in which rare allele counts in case and control samples are treated as vectors in Euclidean space. The geometric framework facilitates a rigorous classification of existing rare variant tests into two broad categories: tests for a difference in the lengths of the case and control vectors, and joint tests for a difference in either the lengths or angles of the two vectors. We demonstrate that genetic architecture of a trait, including the number and frequency of risk alleles, directly relates to the behavior of the length and joint tests. Hence, the geometric framework allows prediction of which tests will perform best under different disease models. Furthermore, the structure of the geometric framework immediately suggests additional classes and types of rare variant tests. We consider two general classes of tests which show robustness to noncausal and protective variants. The geometric framework introduces a novel and unique method to assess current rare variant methodology and provides guidelines for both applied and theoretical researchers. © 2013 Wiley Periodicals, Inc.

Variants at the 9p21 locus and melanoma risk

International Nuclear Information System (INIS)

Maccioni, Livia; Rachakonda, Panduranga Sivaramakrishna; Bermejo, Justo Lorenzo; Planelles, Dolores; Requena, Celia; Hemminki, Kari; Nagore, Eduardo; Kumar, Rajiv

2013-01-01

The influence of variants at the 9p21 locus on melanoma risk has been reported through investigation of CDKN2A variants through candidate gene approach as well as by genome wide association studies (GWAS). In the present study we genotyped, 25 SNPs that tag 273 variants on chromosome 9p21 in 837 melanoma cases and 1154 controls from Spain. Ten SNPs were selected based on previous associations, reported in GWAS, with either melanocytic nevi or melanoma risk or both. The other 15 SNPs were selected to fine map the CDKN2A gene region. All the 10 variants selected from the GWAS showed statistically significant association with melanoma risk. Statistically significant association with melanoma risk was also observed for the carriers of the variant T-allele of rs3088440 (540 C>T) at the 3’ UTR of CDKN2A gene with an OR 1.52 (95% CI 1.14-2.04). Interaction analysis between risk associated polymorphisms and previously genotyped MC1R variants, in the present study, did not show any statistically significant association. Statistical significant association was observed for the interaction between phototypes and the rs10811629 (located in intron 5 of MTAP). The strongest association was observed between the homozygous carrier of the A–allele and phototype II with an OR of 15.93 (95% CI 5.34-47.54). Our data confirmed the association of different variants at chromosome 9p21 with melanoma risk and we also found an association of a variant with skin phototypes

Multiple lupus-associated ITGAM variants alter Mac-1 functions on neutrophils.

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Zhou, Yebin; Wu, Jianming; Kucik, Dennis F; White, Nathan B; Redden, David T; Szalai, Alexander J; Bullard, Daniel C; Edberg, Jeffrey C

2013-11-01

Multiple studies have demonstrated that single-nucleotide polymorphisms (SNPs) in the ITGAM locus (including the nonsynonymous SNPs rs1143679, rs1143678, and rs1143683) are associated with systemic lupus erythematosus (SLE). ITGAM encodes the protein CD11b, a subunit of the β2 integrin Mac-1. The purpose of this study was to determine the effects of ITGAM genetic variation on the biologic functions of neutrophil Mac-1. Neutrophils from ITGAM-genotyped and -sequenced healthy donors were isolated for functional studies. The phagocytic capacity of neutrophil ITGAM variants was probed with complement-coated erythrocytes, serum-treated zymosan, heat-treated zymosan, and IgG-coated erythrocytes. The adhesion capacity of ITGAM variants, in adhering to either purified intercellular adhesion molecule 1 or tumor necrosis factor α-stimulated endothelial cells, was assessed in a flow chamber. Expression levels of total CD11b and activation of CD11b were assessed by flow cytometry. Mac-1-mediated neutrophil phagocytosis, determined in cultures with 2 different complement-coated particles, was significantly reduced in individuals with nonsynonymous variant alleles of ITGAM. This reduction in phagocytosis was related to variation at either rs1143679 (in the β-propeller region) or rs1143678/rs1143683 (highly linked SNPs in the cytoplasmic/calf-1 regions). Phagocytosis mediated by Fcγ receptors was also significantly reduced in donors with variant ITGAM alleles. Similarly, firm adhesion of neutrophils was significantly reduced in individuals with variant ITGAM alleles. These functional alterations were not attributable to differences in total receptor expression or activation. The nonsynonymous ITGAM variants rs1143679 and rs1143678/rs113683 contribute to altered Mac-1 function on neutrophils. These results underscore the need to consider multiple nonsynonymous SNPs when assessing the functional consequences of ITGAM variation on immune cell processes and the risk of SLE

Expression of sterol regulatory element-binding transcription factor (SREBF 2 and SREBF cleavage-activating protein (SCAP in human atheroma and the association of their allelic variants with sudden cardiac death

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Kytömäki Leena

2008-12-01

Full Text Available Abstract Background Disturbed cellular cholesterol homeostasis may lead to accumulation of cholesterol in human atheroma plaques. Cellular cholesterol homeostasis is controlled by the sterol regulatory element-binding transcription factor 2 (SREBF-2 and the SREBF cleavage-activating protein (SCAP. We investigated whole genome expression in a series of human atherosclerotic samples from different vascular territories and studied whether the non-synonymous coding variants in the interacting domains of two genes, SREBF-2 1784G>C (rs2228314 and SCAP 2386A>G, are related to the progression of coronary atherosclerosis and the risk of pre-hospital sudden cardiac death (SCD. Methods Whole genome expression profiling was completed in twenty vascular samples from carotid, aortic and femoral atherosclerotic plaques and six control samples from internal mammary arteries. Three hundred sudden pre-hospital deaths of middle-aged (33–69 years Caucasian Finnish men were subjected to detailed autopsy in the Helsinki Sudden Death Study. Coronary narrowing and areas of coronary wall covered with fatty streaks or fibrotic, calcified or complicated lesions were measured and related to the SREBF-2 and SCAP genotypes. Results Whole genome expression profiling showed a significant (p = 0.02 down-regulation of SREBF-2 in atherosclerotic carotid plaques (types IV-V, but not in the aorta or femoral arteries (p = NS for both, as compared with the histologically confirmed non-atherosclerotic tissues. In logistic regression analysis, a significant interaction between the SREBF-2 1784G>C and the SCAP 2386A>G genotype was observed on the risk of SCD (p = 0.046. Men with the SREBF-2 C allele and the SCAP G allele had a significantly increased risk of SCD (OR 2.68, 95% CI 1.07–6.71, compared to SCAP AA homologous subjects carrying the SREBF-2 C allele. Furthermore, similar trends for having complicated lesions and for the occurrence of thrombosis were found, although the

Blood type, ABO genetic variants, and ovarian cancer survival.

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Gabriella D Cozzi

Full Text Available Blood type A and the A1 allele have been associated with increased ovarian cancer risk. With only two small studies published to date, evidence for an association between ABO blood type and ovarian cancer survival is limited.We conducted a retrospective cohort study of Tumor Registry confirmed ovarian cancer cases from the Vanderbilt University Medical Center with blood type from linked laboratory reports and ABO variants from linked Illumina Exome BeadChip data. Associations with overall survival (OS were quantified by hazard ratios (HR and confidence intervals (CI from proportional hazards regression models; covariates included age, race, stage, grade, histologic subtype, and year of diagnosis.ABO phenotype (N = 694 and/or genotype (N = 154 data were available for 713 predominantly Caucasian (89.3% cases. In multivariable models, blood type A had significantly better OS compared to either O (HR: 0.75, 95% CI: 0.60-0.93 or all non-A (HR: 0.77, 95% CI: 0.63-0.94 cases. Similarly, missense rs1053878 minor allele carriers (A2 had better OS (HR: 0.50, 95% CI: 0.25-0.99. Among Caucasians, this phenotype association was strengthened, but the genotype association was attenuated; instead, four variants sharing moderate linkage disequilibrium with the O variant were associated with better OS (HR: 0.62, 95% CI: 0.39-0.99 in unadjusted models.Blood type A was significantly associated with longer ovarian cancer survival in the largest such study to date. This finding was supported by genetic analysis, which implicated the A2 allele, although O related variants also had suggestive associations. Further research on ABO and ovarian cancer survival is warranted.

Identification of a novel CHEK2 variant and assessment of its contribution to the risk of breast cancer in French Canadian women.

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Novak, David J; Chen, Long Qi; Ghadirian, Parviz; Hamel, Nancy; Zhang, Phil; Rossiny, Vanessa; Cardinal, Guy; Robidoux, André; Tonin, Patricia N; Rousseau, Francois; Narod, Steven A; Foulkes, William D

2008-08-15

BRCA1 and BRCA2 account for the majority of the known familial breast cancer risk, however, the impact of other cancer susceptibility genes largely remains to be elucidated. Checkpoint Kinase 2 (CHEK2) is an important signal transducer of cellular responses to DNA damage, whose defects have been associated with an increase in breast cancer risk. Previous studies have identified low penetrance CHEK2 alleles such as 1100delC and I157T, as well as variants such as S428F in the Ashkenazi Jewish population and IVS2 + 1G>A in the Polish population. No founder allele has been specifically identified in the French Canadian population. The 14 coding exons of CHEK2 were fully sequenced for variant alleles in a panel of 25 affected French Canadian women and 25 healthy controls. Two variants were identified of which one novel variant was further screened for in an additional panel of 667 breast cancer patients and 6548 healthy controls. Additional genotyping was conducted using allele specific PCR and a restriction digest assay. Significance of amino acid substitutions were deduced by employing comparative analysis techniques. Two variants were identified: the previously reported silent substitution 252A>G (E84E) and the novel missense variant, 1217G>A (R406H). No significant difference in allele distribution between French Canadian women with breast cancer and healthy controls was observed (3/692, 0.43% vs. 22/6573, 0.33%, respectively, P = 0.73). The novel CHEK2 missense variant identified in this study, R406H, is unlikely to contribute to breast cancer risk in French Canadian women.

Identification of a novel CHEK2 variant and assessment of its contribution to the risk of breast cancer in French Canadian women

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Cardinal Guy

2008-08-01

Full Text Available Abstract Background BRCA1 and BRCA2 account for the majority of the known familial breast cancer risk, however, the impact of other cancer susceptibility genes largely remains to be elucidated. Checkpoint Kinase 2 (CHEK2 is an important signal transducer of cellular responses to DNA damage, whose defects have been associated with an increase in breast cancer risk. Previous studies have identified low penetrance CHEK2 alleles such as 1100delC and I157T, as well as variants such as S428F in the Ashkenazi Jewish population and IVS2 + 1G>A in the Polish population. No founder allele has been specifically identified in the French Canadian population. Methods The 14 coding exons of CHEK2 were fully sequenced for variant alleles in a panel of 25 affected French Canadian women and 25 healthy controls. Two variants were identified of which one novel variant was further screened for in an additional panel of 667 breast cancer patients and 6548 healthy controls. Additional genotyping was conducted using allele specific PCR and a restriction digest assay. Significance of amino acid substitutions were deduced by employing comparative analysis techniques. Results Two variants were identified: the previously reported silent substitution 252A>G (E84E and the novel missense variant, 1217G>A (R406H. No significant difference in allele distribution between French Canadian women with breast cancer and healthy controls was observed (3/692, 0.43% vs. 22/6573, 0.33%, respectively, P = 0.73. Conclusion The novel CHEK2 missense variant identified in this study, R406H, is unlikely to contribute to breast cancer risk in French Canadian women.

Molecular characterization of a genetic variant of the steroid hormone-binding globulin gene in heterozygous subjects

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Hardy, D.O.; Catterall, J.F. [Population Council, New York, NY (United States); Carino, C. [Instituto National de la Nutricion, Mexico City, MX (United States)] [and others

1995-04-01

Steroid hormone-binding globulin in human serum displays different isoelectric focusing (IEF) patterns among individuals, suggesting genetic variation in the gene for this extracellular steroid carrier protein. Analysis of allele frequencies and family studies suggested the existence of two codominant alleles of the gene. Subsequent determination of the molecular basis of a variant of the gene was carried out using DNA from homozygous individuals from a single Belgian family. It was of interest to characterize other variant individuals to determine whether all variants identified by IEF phenotyping were caused by the same mutation or whether other mutations occurred in the gene in different populations. Previous studies identified Mexican subjects who were heterozygous for the variant IEF phenotype. Denaturing gradient gel electrophoresis was used to localize the mutation in these subjects and to purify the variant allele for DNA sequence analysis. The results show that the mutation in this population is identical to that identified in the Belgian family, and no other mutations were detected in the gene. These data represent the first analysis of steroid hormone-binding globulin gene variation in heterozygous subjects and further support the conclusion of biallelism of the gene worldwide. 11 refs., 2 figs., 1 tab.

Distribution and medical impact of loss-of-function variants in the Finnish founder population

NARCIS (Netherlands)

Lim, Elaine T.; Würtz, Peter; Havulinna, Aki S.; Palta, Priit; Tukiainen, Taru; Rehnström, Karola; Esko, Tõnu; Mägi, Reedik; Inouye, Michael; Lappalainen, Tuuli; Chan, Yingleong; Salem, Rany M.; Lek, Monkol; Flannick, Jason; Sim, Xueling; Manning, Alisa; Ladenvall, Claes; Bumpstead, Suzannah; Hämäläinen, Eija; Aalto, Kristiina; Maksimow, Mikael; Salmi, Marko; Blankenberg, Stefan; Ardissino, Diego; Shah, Svati; Horne, Benjamin; McPherson, Ruth; Hovingh, Gerald K.; Reilly, Muredach P.; Watkins, Hugh; Goel, Anuj; Farrall, Martin; Girelli, Domenico; Reiner, Alex P.; Stitziel, Nathan O.; Kathiresan, Sekar; Gabriel, Stacey; Barrett, Jeffrey C.; Lehtimäki, Terho; Laakso, Markku; Groop, Leif; Kaprio, Jaakko; Perola, Markus; McCarthy, Mark I.; Boehnke, Michael; Altshuler, David M.; Lindgren, Cecilia M.; Hirschhorn, Joel N.; Metspalu, Andres; Freimer, Nelson B.; Zeller, Tanja; Jalkanen, Sirpa; Koskinen, Seppo; Raitakari, Olli; Durbin, Richard; MacArthur, Daniel G.; Salomaa, Veikko; Ripatti, Samuli; Daly, Mark J.; Palotie, Aarno

2014-01-01

Exome sequencing studies in complex diseases are challenged by the allelic heterogeneity, large number and modest effect sizes of associated variants on disease risk and the presence of large numbers of neutral variants, even in phenotypically relevant genes. Isolated populations with recent

Molecular analyses of the agouti allele in the Japanese house mouse identify a novel variant of the agouti gene.

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Iwasa, Masahiro A; Kawamura, Sayaka; Myoshu, Hikari; Suzuki, Taichi A

2018-03-01

It has been thought that the Japanese house mouse carries the A w allele at the agouti locus causing light-colored bellies, but they do not always show this coloration. Thus, the presence of the A w allele seems to be doubtful in them. To ascertain whether the A w allele is present, a two-pronged approach was used. First, we compared lengths of DNA fragments obtained from three PCRs conducted on them to the known fragment sizes generated from mouse strains exhibiting homozygosities of either a/a, A/A, or A w /A w . PCR I, PCR II, and PCR III amplify only in the A and A w alleles, the a and A w alleles, and the a allele, respectively, and we detected amplifications in strains with A/A and A w /A w by PCR I, in those with a/a and the Japanese house mouse by PCR II, and in those with a/a by PCR III. Second, we sequenced the exon 1A region of the agouti gene and obtained sequences corresponding to the above strains and the Japanese house mouse, but their sequences were similar to those of the a allele. We concluded that their agouti allele is not identical to the A w allele and seems to be a novel type similar to the a allele.

The risk variant in ODZ4 for bipolar disorder impacts on amygdala activation during reward processing.

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Heinrich, Angela; Lourdusamy, Anbarasu; Tzschoppe, Jelka; Vollstädt-Klein, Sabine; Bühler, Mira; Steiner, Sabina; Bach, Christiane; Poustka, Luise; Banaschewski, Tobias; Barker, Gareth; Büchel, Christian; Conrod, Patricia; Garavan, Hugh; Gallinat, Jürgen; Heinz, Andreas; Ittermann, Bernd; Loth, Eva; Mann, Karl; Martinot, Jean-Luc; Paus, Tomáš; Pausova, Zdenka; Smolka, Michael; Ströhle, Andreas; Struve, Maren; Witt, Stephanie; Flor, Herta; Schumann, Gunter; Rietschel, Marcella; Nees, Frauke

2013-06-01

Bipolar disorder is a severe mood disorder, which normally begins during adolescence or early adulthood and has a heritability of up to 80%. The largest genome-wide association analysis of bipolar disorder recently identified a new genome-wide associated variant in OZD4 (rs12576775). The aim of the present study was to further elucidate the role of this risk variant in the disease process using an imaging genetics approach. As increased amygdala and striatal responses during the processing of reward and emotion are characteristic for bipolar disorder patients, it was tested whether the risk variant has an influence on this endophenotype in healthy adolescents. We examined the impact of the risk variant rs12576775 on functional magnetic resonance imaging data in an adolescent sample (N = 485). Differential activation between carriers of the risk allele (G-allele) and homozygous A-allele carriers in the amygdala and the striatum during a modification of the monetary incentive delay task (examining reward) and a face task (examining emotion) was analyzed. Carriers of the risk allele showed an increased blood oxygen level-dependent response in the amygdala during reward sensitivity (p = 0.05) and reward expectation (p < 0.05) but not during the face task. No significant group differences were found in the striatum during both reward and emotion processing. Our results indicate that the ODZ4 risk variant influences reward processing in the amygdala. Alterations in the processing of emotion may have different underlying mechanisms and need to be further examined. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

FEATURES OF THE CLINICAL SIGNIFICANCE OF POLYMORPHIC VARIANTS OF ENOS AND AGTR2 GENES IN PATIENTS WITH CAD

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A. L. Khokhlov

2016-01-01

Full Text Available Coronary heart disease (CHD is a major cause of mortality. Morphological substrate of CHD in most cases is atherosclerosis, which is based on structural genes polymorphism eNOS and AGTR2. The aim of the study was to study the prevalence of eNOS and AGTR2 genes in patients with coronary artery disease and the association of these genes with coronary heart disease. The study involved 187 patients aged 36 to 86 years (62,2±11,2 with different forms of CHD: stable and unstable angina, myocardial infarction and 45 people without CHD. Determination of gene polymorphisms was performed by real-time PCR analyzer of nucleic acids IQ 5 Bio-Rad. Statistical analysis was performed using Statistica 10.0. The study revealed a significant difference between the incidence of homozygous AA allelic variant gene AGTR2 group of patients with myocardial infarction and the comparison group; polymorphic variant AA AGTR2 gene is associated with earlier onset of coronary artery disease; It found that carriers of the polymorphic variant gene GA AGTR2 beginning statistically CHD occurred significantly later than in carriers of alleles GG and AA; age CHD debut TT allele carriers of the eNOS gene is associated with an earlier onset of the disease and statistically significantly different from the age of first CHD in carriers of alleles of polymorphic variants of GG and GT; revealed a positive correlation between the polymorphic allele AGTR2 gene with the presence of arterial hypertension in patients with coronary artery disease; It determined that the T allele carriers of the polymorphic gene eNOS is associated more early onset of hypertension, found the association of the polymorphic allele gene AGTR2 the need to use higher doses of ACE inhibitor — perindopril.

Association between sequence variants in panicle development genes and the number of spikelets per panicle in rice.

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Jang, Su; Lee, Yunjoo; Lee, Gileung; Seo, Jeonghwan; Lee, Dongryung; Yu, Yoye; Chin, Joong Hyoun; Koh, Hee-Jong

2018-01-15

Balancing panicle-related traits such as panicle length and the numbers of primary and secondary branches per panicle, is key to improving the number of spikelets per panicle in rice. Identifying genetic information contributes to a broader understanding of the roles of gene and provides candidate alleles for use as DNA markers. Discovering relations between panicle-related traits and sequence variants allows opportunity for molecular application in rice breeding to improve the number of spikelets per panicle. In total, 142 polymorphic sites, which constructed 58 haplotypes, were detected in coding regions of ten panicle development gene and 35 sequence variants in six genes were significantly associated with panicle-related traits. Rice cultivars were clustered according to their sequence variant profiles. One of the four resultant clusters, which contained only indica and tong-il varieties, exhibited the largest average number of favorable alleles and highest average number of spikelets per panicle, suggesting that the favorable allele combination found in this cluster was beneficial in increasing the number of spikelets per panicle. Favorable alleles identified in this study can be used to develop functional markers for rice breeding programs. Furthermore, stacking several favorable alleles has the potential to substantially improve the number of spikelets per panicle in rice.

Allele-specific deletions in mouse tumors identify Fbxw7 as germline modifier of tumor susceptibility.

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Jesus Perez-Losada

Full Text Available Genome-wide association studies (GWAS have been successful in finding associations between specific genetic variants and cancer susceptibility in human populations. These studies have identified a range of highly statistically significant associations between single nucleotide polymorphisms (SNPs and susceptibility to development of a range of human tumors. However, the effect of each SNP in isolation is very small, and all of the SNPs combined only account for a relatively minor proportion of the total genetic risk (5-10%. There is therefore a major requirement for alternative routes to the discovery of genetic risk factors for cancer. We have previously shown using mouse models that chromosomal regions harboring susceptibility genes identified by linkage analysis frequently exhibit allele-specific genetic alterations in tumors. We demonstrate here that the Fbxw7 gene, a commonly mutated gene in a wide range of mouse and human cancers, shows allele-specific deletions in mouse lymphomas and skin tumors. Lymphomas from three different F1 hybrids show 100% allele-specificity in the patterns of allelic loss. Parental alleles from 129/Sv or Spretus/Gla mice are lost in tumors from F1 hybrids with C57BL/6 animals, due to the presence of a specific non-synonymous coding sequence polymorphism at the N-terminal portion of the gene. A specific genetic test of association between this SNP and lymphoma susceptibility in interspecific backcross mice showed a significant linkage (p = 0.001, but only in animals with a functional p53 gene. These data therefore identify Fbxw7 as a p53-dependent tumor susceptibility gene. Increased p53-dependent tumor susceptibility and allele-specific losses were also seen in a mouse skin model of skin tumor development. We propose that analysis of preferential allelic imbalances in tumors may provide an efficient means of uncovering genetic variants that affect mouse and human tumor susceptibility.

TRPV6 alleles do not influence prostate cancer progression

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Kessler, Thorsten; Wissenbach, Ulrich; Grobholz, Rainer; Flockerzi, Veit

2009-01-01

The transient receptor potential, subfamily V, member 6 (TRPV6) is a Ca 2+ selective cation channel. Several studies have shown that TRPV6 transcripts are expressed in locally advanced prostatic adenocarcinoma, metastatic and androgen-insensitive prostatic lesions but are undetectable in healthy prostate tissue and benign prostatic hyperplasia. Two allelic variants of the human trpv6 gene have been identified which are transcribed into two independent mRNAs, TRPV6a and TRPV6b. We now asked, whether the trpv6a allele is correlated with the onset of prostate cancer, with the Gleason score and the tumour stage. Genomic DNA of prostate cancer patients and control individuals was isolated from resections of prostatic adenocarcinomas and salivary fluid respectively. Genotyping of SNPs of the TRPV6 gene was performed by restriction length polymorphism or by sequencing analysis. RNA used for RT-PCR was isolated from prostate tissue. Data sets were analyzed by Chi-Square test. We first characterized in detail the five polymorphisms present in the protein coding exons of the trpv6 gene and show that these polymorphisms are coupled and are underlying the TRPV6a and the TRPV6b variants. Next we analysed the frequencies of the two TRPV6 alleles using genomic DNA from saliva samples of 169 healthy individuals. The homozygous TRPV6b genotype predominated with 86%, whereas no homozygous TRPV6a carriers could be identified. The International HapMap Project identified a similar frequency for an Utah based population whereas in an African population the a-genotype prevailed. The incidence of prostate cancer is several times higher in African populations than in non-African and we then investigated the TRPV6a/b frequencies in 141 samples of prostatic adenocarcinoma. The TRPV6b allele was found in 87% of the samples without correlation with Gleason score and tumour stage. Our results show that the frequencies of trpv6 alleles in healthy control individuals and prostate cancer patients

TRPV6 alleles do not influence prostate cancer progression.

Science.gov (United States)

Kessler, Thorsten; Wissenbach, Ulrich; Grobholz, Rainer; Flockerzi, Veit

2009-10-26

The transient receptor potential, subfamily V, member 6 (TRPV6) is a Ca(2+) selective cation channel. Several studies have shown that TRPV6 transcripts are expressed in locally advanced prostatic adenocarcinoma, metastatic and androgen-insensitive prostatic lesions but are undetectable in healthy prostate tissue and benign prostatic hyperplasia. Two allelic variants of the human trpv6 gene have been identified which are transcribed into two independent mRNAs, TRPV6a and TRPV6b. We now asked, whether the trpv6a allele is correlated with the onset of prostate cancer, with the Gleason score and the tumour stage. Genomic DNA of prostate cancer patients and control individuals was isolated from resections of prostatic adenocarcinomas and salivary fluid respectively. Genotyping of SNPs of the TRPV6 gene was performed by restriction length polymorphism or by sequencing analysis. RNA used for RT-PCR was isolated from prostate tissue. Data sets were analyzed by Chi-Square test. We first characterized in detail the five polymorphisms present in the protein coding exons of the trpv6 gene and show that these polymorphisms are coupled and are underlying the TRPV6a and the TRPV6b variants. Next we analysed the frequencies of the two TRPV6 alleles using genomic DNA from saliva samples of 169 healthy individuals. The homozygous TRPV6b genotype predominated with 86%, whereas no homozygous TRPV6a carriers could be identified. The International HapMap Project identified a similar frequency for an Utah based population whereas in an African population the a-genotype prevailed. The incidence of prostate cancer is several times higher in African populations than in non-African and we then investigated the TRPV6a/b frequencies in 141 samples of prostatic adenocarcinoma. The TRPV6b allele was found in 87% of the samples without correlation with Gleason score and tumour stage. Our results show that the frequencies of trpv6 alleles in healthy control individuals and prostate cancer patients

TRPV6 alleles do not influence prostate cancer progression

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Flockerzi Veit

2009-10-01

Full Text Available Abstract Background The transient receptor potential, subfamily V, member 6 (TRPV6 is a Ca2+ selective cation channel. Several studies have shown that TRPV6 transcripts are expressed in locally advanced prostatic adenocarcinoma, metastatic and androgen-insensitive prostatic lesions but are undetectable in healthy prostate tissue and benign prostatic hyperplasia. Two allelic variants of the human trpv6 gene have been identified which are transcribed into two independent mRNAs, TRPV6a and TRPV6b. We now asked, whether the trpv6a allele is correlated with the onset of prostate cancer, with the Gleason score and the tumour stage. Methods Genomic DNA of prostate cancer patients and control individuals was isolated from resections of prostatic adenocarcinomas and salivary fluid respectively. Genotyping of SNPs of the TRPV6 gene was performed by restriction length polymorphism or by sequencing analysis. RNA used for RT-PCR was isolated from prostate tissue. Data sets were analyzed by Chi-Square test. Results We first characterized in detail the five polymorphisms present in the protein coding exons of the trpv6 gene and show that these polymorphisms are coupled and are underlying the TRPV6a and the TRPV6b variants. Next we analysed the frequencies of the two TRPV6 alleles using genomic DNA from saliva samples of 169 healthy individuals. The homozygous TRPV6b genotype predominated with 86%, whereas no homozygous TRPV6a carriers could be identified. The International HapMap Project identified a similar frequency for an Utah based population whereas in an African population the a-genotype prevailed. The incidence of prostate cancer is several times higher in African populations than in non-African and we then investigated the TRPV6a/b frequencies in 141 samples of prostatic adenocarcinoma. The TRPV6b allele was found in 87% of the samples without correlation with Gleason score and tumour stage. Conclusion Our results show that the frequencies of trpv6

Common Variants at VRK2 and TCF4 Conferring Risk of Schizophrenia

DEFF Research Database (Denmark)

Steinberg, Stacy; de Jong, Simone; Andreassen, Ole A

2011-01-01

Common sequence variants have recently joined rare structural polymorphisms as genetic factors with strong evidence for association with schizophrenia. Here we extend our previous genome-wide association (GWA) study and meta-analysis (totalling 7,946 cases and 19,036 controls) by examining...... an expanded set of variants using an enlarged follow-up sample (up to 10,260 cases and 23,500 controls). In addition to previously-reported alleles in the major histocompatibility complex (MHC) region, near neurogranin (NRGN) and in an intron of transcription factor 4 (TCF4), we find two novel variants...... showing genome-wide significant association: rs2312147[C], upstream of vaccinia-related kinase 2 (VRK2) (OR = 1.09, P = 1.9 x 10(-9)), and rs4309482[A], between coiled-coiled domain containing 68 (CCDC68) and TCF4, about 400 kb from the previously-described risk allele, but not accounted for by its...

High prevalence of the c.74A>C SPINK1 variant in miniature and standard Schnauzers.

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Furrow, E; Armstrong, P J; Patterson, E E

2012-01-01

Variants in the serine protease inhibitor Kazal type 1 (SPINK1) gene have been associated with pancreatitis in Miniature Schnauzers. Replication of the association in an independent population is necessary to determine if genetic screening for SPINK1 variants should be considered in clinical practice. An association between the SPINK1 exonic variant c.74A > C and pancreatitis exists in Miniature Schnauzers. In addition, the variant is absent or rare in Standard Schnauzers, a related breed that is not reported to have an increased risk for pancreatitis. Case-control study. Seventeen Miniature Schnauzers with pancreatitis (cases), 60 mature Miniature Schnauzers with no substantial history of gastrointestinal signs in their lifetime (controls), and 31 Standard Schnauzers of unknown pancreatitis status. A PCR-RFLP assay was used to genotype dogs for the c.74A > C SPINK1 variant. Allele and genotype frequencies were reported for Schnauzers and compared between case and control Miniature Schnauzers. The c.74A > C variant was the major allele in both Schnauzer breeds with a frequency of 0.77 in Miniatures and 0.55 in Standards. The allele and genotype frequencies were similar between Miniature Schnauzers with and without a history of pancreatitis and did not impart an increased risk for pancreatitis. Genotyping a larger population of the Miniature Schnauzer breed than a previous study, along with a Standard Schnauzer cohort, demonstrated that the SPINK1 c.74A > C variant is a common polymorphism in the Schnauzer lineage. Furthermore, we were unable to confirm a relationship between the variant and clinically detectable pancreatitis in Miniature Schnauzers. Copyright © 2012 by the American College of Veterinary Internal Medicine.

Myotonic dystrophy type 1: role of CCG, CTC and CGG interruptions within DMPK alleles in the pathogenesis and molecular diagnosis.

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Santoro, M; Masciullo, M; Silvestri, G; Novelli, G; Botta, A

2017-10-01

Myotonic dystrophy type 1 (DM1) is a multisystem neuromuscular disease caused by a CTG triplet expansion in the 3'-untranslated region (3'-UTR) of DMPK gene. This CTG array is usually uninterrupted in both healthy and DM1 patients, but recent studies identified pathological variant expansions containing unstable CCG, CTC and CGG interruptions with a prevalence of 3-5% of cases. In this review, we will describe the clinical, molecular and genetic issues related to the occurrence of variant expansions associated with DM1. Indeed, the identification of these complex DMPK alleles leads to practical consequences in DM1 genetic counseling and testing, because these exams can give false negative results. Moreover, DM1 patients carrying interrupted alleles can manifest either additional atypical neurological symptoms or, conversely, mild, late-onset forms. Therefore, the prognosis of the disease in these patients is difficult to determine because of the great uncertainty about the genotype-phenotype correlations. We will discuss the putative effects of the variant DM1 alleles on the pathogenic disease mechanisms, including mitotic and meiotic repeats instability and splicing alteration typical of DM1 tissues. Interruptions within the DMPK expanded alleles could also interfere with the chromatin structure, the transcriptional activity of the DM1 locus and the interaction with RNA CUG-binding proteins. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Blood type, ABO genetic variants, and ovarian cancer survival

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Cozzi, Gabriella D.; Levinson, Rebecca T.; Toole, Hilary; Snyder, Malcolm-Robert; Deng, Angie; Crispens, Marta A.; Khabele, Dineo; Beeghly-Fadiel, Alicia

2017-01-01

Objective Blood type A and the A1 allele have been associated with increased ovarian cancer risk. With only two small studies published to date, evidence for an association between ABO blood type and ovarian cancer survival is limited. Methods We conducted a retrospective cohort study of Tumor Registry confirmed ovarian cancer cases from the Vanderbilt University Medical Center with blood type from linked laboratory reports and ABO variants from linked Illumina Exome BeadChip data. Associations with overall survival (OS) were quantified by hazard ratios (HR) and confidence intervals (CI) from proportional hazards regression models; covariates included age, race, stage, grade, histologic subtype, and year of diagnosis. Results ABO phenotype (N = 694) and/or genotype (N = 154) data were available for 713 predominantly Caucasian (89.3%) cases. In multivariable models, blood type A had significantly better OS compared to either O (HR: 0.75, 95% CI: 0.60–0.93) or all non-A (HR: 0.77, 95% CI: 0.63–0.94) cases. Similarly, missense rs1053878 minor allele carriers (A2) had better OS (HR: 0.50, 95% CI: 0.25–0.99). Among Caucasians, this phenotype association was strengthened, but the genotype association was attenuated; instead, four variants sharing moderate linkage disequilibrium with the O variant were associated with better OS (HR: 0.62, 95% CI: 0.39–0.99) in unadjusted models. Conclusions Blood type A was significantly associated with longer ovarian cancer survival in the largest such study to date. This finding was supported by genetic analysis, which implicated the A2 allele, although O related variants also had suggestive associations. Further research on ABO and ovarian cancer survival is warranted. PMID:28448592

Autozygosity reveals recessive mutations and novel mechanisms in dominant genes: implications in variant interpretation

KAUST Repository

Monies, Dorota

2017-04-06

The purpose of this study is to describe recessive alleles in strictly dominant genes. Identifying recessive mutations in genes for which only dominant disease or risk alleles have been reported can expand our understanding of the medical relevance of these genes both phenotypically and mechanistically. The Saudi population is enriched for autozygosity, which enhances the homozygous occurrence of alleles, including pathogenic alleles in genes that have been associated only with a dominant inheritance pattern.Exome sequencing of patients from consanguineous families with likely recessive phenotypes was performed. In one family, the genotype of the deceased children was inferred from their parents due to lack of available samples.We describe the identification of 11 recessive variants (5 of which are reported here for the first time) in 11 genes for which only dominant disease or risk alleles have been reported. The observed phenotypes for these recessive variants were novel (e.g., FBN2-related myopathy and CSF1R-related brain malformation and osteopetrosis), typical (e.g., ACTG2-related visceral myopathy), or an apparently healthy state (e.g., PDE11A), consistent with the corresponding mouse knockout phenotypes.Our results show that, in the era of genomic sequencing and

The role of functionally defective rare germline variants of sialic acid acetylesterase in autoimmune Addison's disease

Science.gov (United States)

Gan, Earn H; MacArthur, Katie; Mitchell, Anna L; Pearce, Simon H S

2012-01-01

Background Autoimmune Addison's disease (AAD) is a rare condition with a complex genetic basis. A panel of rare and functionally defective genetic variants in the sialic acid acetylesterase (SIAE) gene has recently been implicated in several common autoimmune conditions. We performed a case–control study to determine whether these rare variants are associated with a rarer condition, AAD. Method We analysed nine SIAE gene variants (W48X, M89V, C196F, C226G, R230W, T312M, Y349C, F404S and R479C) in a United Kingdom cohort of 378 AAD subjects and 387 healthy controls. All samples were genotyped using Sequenom iPlex chemistry to characterise primer extension products. Results A heterozygous rare allele at codon 312 (312*M) was found in one AAD patient (0.13%) but was not detected in the healthy controls. The commoner, functionally recessive variant at codon 89 (89*V) was found to be homozygous in two AAD patients but was only found in the heterozygous state in controls. Taking into account all nine alleles examined, 4/378 (1.06%) AAD patients and 1/387 (0.25%) healthy controls carried the defective SIAE alleles, with a calculated odds ratio of 4.13 (95% CI 0.44–97.45, two-tailed P value 0.212, NS). Conclusion We demonstrated the presence of 89*V homozygotes and the 312*M rare allele in the AAD cohort, but overall, our analysis does not support a role for rare variants in SIAE in the pathogenesis of AAD. However, the relatively small collection of AAD patients limits the power to exclude a small effect. PMID:23011869

Angiotensin-converting enzyme (ACE) alleles in the Quechua, a high altitude South American native population.

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Rupert, J L; Devine, D V; Monsalve, M V; Hochachka, P W

1999-01-01

Recently it was reported that an allelic variant of the gene encoding angiotensin-converting enzyme (ACE) was significantly over-represented in a cohort of elite British mountaineers. It was proposed that this may be evidence for a specific genetic factor influencing the human capacity for physical performance. The implication that this allele could enhance performance at high altitude prompted us to determine its frequency in Quechua speaking natives living at altitudes greater than 3000m on the Andean Altiplano in South America. We found that the frequency of the putative performance allele in the Quechuas, although significantly higher than in Caucasians, was not different from lowland Native American populations. This observation suggests that, although the higher frequency of the 'performance allele' may have facilitated the migration of the ancestral Quechua to the highlands, the ACE insertion allele has not been subsequently selected for in this high altitude population.

Variants of Interleukin-22 Gene Confer Predisposition to Autoimmune Thyroid Disease

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Rong-hua Song

2017-01-01

Full Text Available As there are no previous studies on the interleukin-22 (IL-22 variants in autoimmune thyroid disease (AITD, the present study aimed to explore the association between polymorphisms of IL-22 and the predisposition to AITD. The study had 975 AITD patients, including 639 Graves’ disease (GD and 336 Hashimoto’s thyroiditis (HT individuals and 851 healthy cohorts. Ligase detection reaction (LDR and direct sequencing method were used for genotyping the IL-22 gene polymorphisms at rs2046068, rs2227478, rs2227485, rs11611206, and rs1179251. In comparison to female controls, genotype CC of rs1179251 was increased in the female AITD patients. Alleles C at rs2046068, C at rs2227478, and C at rs1179251 linked to the susceptibility of HT males. Genotype CC in rs1179251 was higher in male HT. Variants at rs2046068, rs2227478, and rs1179251 were associated with the AITD teenagers. Besides, genotype GG in rs11611206 was correlated with thyroid-associated ophthalmopathy (TAO. Moreover, allele G at rs11611206 was associated with decreased risk for TAO by 28.9%. Similarly, genotype CC of rs1179251 and genotype GG of rs11611206 were associated with Graves’ ophthalmopathy (GO. Allele G in rs11611206 increased people with HT towards the predisposition of hypothyroidism. In conclusion, genetic variants of IL-22 are associated with the occurrence of AITD.

Analysis of protein-altering variants in telomerase genes and their association with MUC5B common variant status in patients with idiopathic pulmonary fibrosis: a candidate gene sequencing study.

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Dressen, Amy; Abbas, Alexander R; Cabanski, Christopher; Reeder, Janina; Ramalingam, Thirumalai R; Neighbors, Margaret; Bhangale, Tushar R; Brauer, Matthew J; Hunkapiller, Julie; Reeder, Jens; Mukhyala, Kiran; Cuenco, Karen; Tom, Jennifer; Cowgill, Amy; Vogel, Jan; Forrest, William F; Collard, Harold R; Wolters, Paul J; Kropski, Jonathan A; Lancaster, Lisa H; Blackwell, Timothy S; Arron, Joseph R; Yaspan, Brian L

2018-06-08

Idiopathic pulmonary fibrosis (IPF) risk has a strong genetic component. Studies have implicated variations at several loci, including TERT, surfactant genes, and a single nucleotide polymorphism at chr11p15 (rs35705950) in the intergenic region between TOLLIP and MUC5B. Patients with IPF who have risk alleles at rs35705950 have longer survival from the time of IPF diagnosis than do patients homozygous for the non-risk allele, whereas patients with shorter telomeres have shorter survival times. We aimed to assess whether rare protein-altering variants in genes regulating telomere length are enriched in patients with IPF homozygous for the non-risk alleles at rs35705950. Between Nov 1, 2014, and Nov 1, 2016, we assessed blood samples from patients aged 40 years or older and of European ancestry with sporadic IPF from three international phase 3 clinical trials (INSPIRE, CAPACITY, ASCEND), one phase 2 study (RIFF), and US-based observational studies (Vanderbilt Clinical Interstitial Lung Disease Registry and the UCSF Interstitial Lung Disease Clinic registry cohorts) at the Broad Institute (Cambridge, MA, USA) and Human Longevity (San Diego, CA, USA). We also assessed blood samples from non-IPF controls in several clinical trials. We did whole-genome sequencing to assess telomere length and identify rare protein-altering variants, stratified by rs35705950 genotype. We also assessed rare functional variation in TERT exons and compared telomere length and disease progression across genotypes. We assessed samples from 1510 patients with IPF and 1874 non-IPF controls. 30 (3%) of 1046 patients with an rs35705950 risk allele had a rare protein-altering variant in TERT compared with 34 (7%) of 464 non-risk allele carriers (odds ratio 0·40 [95% CI 0·24-0·66], p=0·00039). Subsequent analyses identified enrichment of rare protein-altering variants in PARN and RTEL1, and rare variation in TERC in patients with IPF compared with controls. We expanded our study population to

The BTNL2 A allele variant is frequent in Danish patients with sarcoidosis

DEFF Research Database (Denmark)

Milman, Nils; Svendsen, Claus Bo; Nielsen, Finn Cilius

2011-01-01

The butyrophilin-like 2 (BTNL2) gene is located on chromosome 6p21.3 close to the HLA-class II genes. An association has been reported between sarcoidosis and a single nucleotide polymorphism in BTNL2, rs2076530, also termed the A allele....

Association of HFE common mutations with Parkinson's disease, Alzheimer's disease and mild cognitive impairment in a Portuguese cohort

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Morgadinho Ana S

2006-07-01

Full Text Available Abstract Background Pathological brain iron deposition has been implicated as a source of neurotoxic reactive oxygen species in Alzheimer (AD and Parkinson diseases (PD. Iron metabolism is associated with the gene hemochromatosis (HFE Human genome nomenclature committee ID:4886, and mutations in HFE are a cause of the iron mismetabolism disease, hemochromatosis. Several reports have tested the association of HFE variants with neurodegenerative diseases, such as AD and PD with conflicting results. Methods Genotypes were analysed for the two most common variants of HFE in a series of 130 AD, 55 Mild Cognitive Impairment (MCI and 132 PD patients. Additionally, a series of 115 healthy age-matched controls was also screened. Results A statistically significant association was found in the PD group when compared to controls, showing that the presence of the C282Y variant allele may confer higher risk for developing the disease. Conclusion Taken together these results suggest that the common variants in HFE may be a risk factor for PD, but not for AD in the Portuguese population.

Association of the C47T Polymorphism in SOD2 with Amnestic Mild Cognitive Impairment and Alzheimer’s Disease in Carriers of the APOEε4 Allele

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David Gamarra

2015-01-01

Full Text Available Oxidative stress plays an important part in amnestic mild cognitive impairment (aMCI, the prodromal phase of Alzheimer’s disease (AD. Recent evidence shows that polymorphisms in the SOD2 gene affect the elimination of the reactive oxygen species (ROS generated in mitochondria. The aim of this study was to determine whether the functional rs4880 SNP in the SOD2 gene is a risk factor associated with aMCI and sporadic AD. 216 subjects with aMCI, 355 with AD, and 245 controls have been studied. The SNP rs4880 of the SOD2 gene was genotyped by RT-PCR and the APOE genotype was determined by PCR and RFLPs. Different multinomial logistic regression models were used to determine the risk levels for aMCI and AD. Although the T allele of the SOD2 rs4880 SNP gene (rs4880-T is not an independent risk for aMCI or AD, this allele increases the risk to aMCI patients carrying at least one APOEε4 allele. Moreover, rs4880-T allele and APOEε4 allele combination has been found to produce an increased risk for AD compared to aMCI reference patients. These results suggest that APOEε4 and rs4880-T genotype may be a risk for aMCI and a predictor of progression from aMCI to AD.

Identification of genomic variants putatively targeted by selection during dog domestication.

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Cagan, Alex; Blass, Torsten

2016-01-12

Dogs [Canis lupus familiaris] were the first animal species to be domesticated and continue to occupy an important place in human societies. Recent studies have begun to reveal when and where dog domestication occurred. While much progress has been made in identifying the genetic basis of phenotypic differences between dog breeds we still know relatively little about the genetic changes underlying the phenotypes that differentiate all dogs from their wild progenitors, wolves [Canis lupus]. In particular, dogs generally show reduced aggression and fear towards humans compared to wolves. Therefore, selection for tameness was likely a necessary prerequisite for dog domestication. With the increasing availability of whole-genome sequence data it is possible to try and directly identify the genetic variants contributing to the phenotypic differences between dogs and wolves. We analyse the largest available database of genome-wide polymorphism data in a global sample of dogs 69 and wolves 7. We perform a scan to identify regions of the genome that are highly differentiated between dogs and wolves. We identify putatively functional genomic variants that are segregating or at high frequency [> = 0.75 Fst] for alternative alleles between dogs and wolves. A biological pathways analysis of the genes containing these variants suggests that there has been selection on the 'adrenaline and noradrenaline biosynthesis pathway', well known for its involvement in the fight-or-flight response. We identify 11 genes with putatively functional variants fixed for alternative alleles between dogs and wolves. The segregating variants in these genes are strong candidates for having been targets of selection during early dog domestication. We present the first genome-wide analysis of the different categories of putatively functional variants that are fixed or segregating at high frequency between a global sampling of dogs and wolves. We find evidence that selection has been strongest

A robust approach to identifying tissue-specific gene expression regulatory variants using personalized human induced pluripotent stem cells.

Directory of Open Access Journals (Sweden)

Je-Hyuk Lee

2009-11-01

Full Text Available Normal variation in gene expression due to regulatory polymorphisms is often masked by biological and experimental noise. In addition, some regulatory polymorphisms may become apparent only in specific tissues. We derived human induced pluripotent stem (iPS cells from adult skin primary fibroblasts and attempted to detect tissue-specific cis-regulatory variants using in vitro cell differentiation. We used padlock probes and high-throughput sequencing for digital RNA allelotyping and measured allele-specific gene expression in primary fibroblasts, lymphoblastoid cells, iPS cells, and their differentiated derivatives. We show that allele-specific expression is both cell type and genotype-dependent, but the majority of detectable allele-specific expression loci remains consistent despite large changes in the cell type or the experimental condition following iPS reprogramming, except on the X-chromosome. We show that our approach to mapping cis-regulatory variants reduces in vitro experimental noise and reveals additional tissue-specific variants using skin-derived human iPS cells.

The new allelic variant of the subtilase cytotoxin (subAB2) is common among Shiga toxin-producing Escherichia coli strains from large game animals and their meat and meat products.

Science.gov (United States)

Sánchez, Sergio; Díaz-Sánchez, Sandra; Martínez, Remigio; Llorente, María Teresa; Herrera-León, Silvia; Vidal, Dolors

2013-10-25

Subtilase cytotoxin (SubAB) is an AB5 toxin produced by Shiga toxin (Stx)-producing Escherichia coli (STEC) strains usually lacking the eae gene product intimin. Two allelic variants of SubAB encoding genes have been described: subAB1, located on a plasmid, and subAB2, located on a pathogenicity island (PAI) together with tia gene. While subAB1 has been reported to be more frequent among bovine strains, subAB2 has been mainly associated with strains from small ruminants. We investigated the presence of the two variants of subAB among 59 eae-negative STEC from large game animals (deer and wild boar) and their meat and meat products in order to assess the role of other species in the epidemiology of subAB-positive, eae-negative STEC. For this approach, the strains were PCR-screened for the presence of subAB, including the specific detection of both allelic variants, for the presence of saa, tia and sab, and for stx subtyping. Overall, subAB genes were detected in 71.2% of the strains: 84.1% of the strains from deer and 33.3% of the strains from wild boar. Most of them (97.6%) possessed subAB2 and most of these subAB2-positive strains (92.7%) were also positive for tia and negative for saa, suggesting the presence of the subAB2-harbouring PAI. Subtype stx2b was present in most of the strains (67.8%) and a statistically significant association could be established between subAB2 and stx2b. Our results suggest that large game animals, mainly deer, may represent an important animal reservoir of subAB2-positive, eae-negative STEC, and also highlight the risk of human infection posed by the consumption of large game meat and meat products. Copyright © 2013 Elsevier B.V. All rights reserved.

ABCA7 rare variants and Alzheimer disease risk.

Science.gov (United States)

Le Guennec, Kilan; Nicolas, Gaël; Quenez, Olivier; Charbonnier, Camille; Wallon, David; Bellenguez, Céline; Grenier-Boley, Benjamin; Rousseau, Stéphane; Richard, Anne-Claire; Rovelet-Lecrux, Anne; Bacq, Delphine; Garnier, Jean-Guillaume; Olaso, Robert; Boland, Anne; Meyer, Vincent; Deleuze, Jean-François; Amouyel, Philippe; Munter, Hans Markus; Bourque, Guillaume; Lathrop, Mark; Frebourg, Thierry; Redon, Richard; Letenneur, Luc; Dartigues, Jean-François; Pasquier, Florence; Rollin-Sillaire, Adeline; Génin, Emmanuelle; Lambert, Jean-Charles; Hannequin, Didier; Campion, Dominique

2016-06-07

To study the association between ABCA7 rare coding variants and Alzheimer disease (AD) in a case-control setting. We conducted a whole exome analysis among 484 French patients with early-onset AD and 590 ethnically matched controls. After collapsing rare variants (minor allele frequency ≤1%), we detected an enrichment of ABCA7 loss of function (LOF) and predicted damaging missense variants in cases (odds ratio [OR] 3.40, 95% confidence interval [CI] 1.68-7.35, p = 0.0002). Performing a meta-analysis with previously published data, we found that in a combined sample of 1,256 patients and 1,347 controls from France and Belgium, the OR was 2.81 (95% CI 1.89-4.20, p = 3.60 × 10(-7)). These results confirm that ABCA7 LOF variants are enriched in patients with AD and extend this finding to predicted damaging missense variants. © 2016 American Academy of Neurology.

Electrophoretic variants of blood proteins in Japanese, 7

International Nuclear Information System (INIS)

Satoh, Chiyoko; Takahashi, Norio; Kimura, Yasukazu; Miura, Akiko; Kaneko, Junko; Fujita, Mikio; Toyama, Kyoko.

1986-11-01

A total of 16,835 children, of whom 11,737 are unrelated, from Hiroshima and Nagasaki were examined for erythrocyte cytoplasmic glutamate-oxaloacetate transaminase (GOT1) by starch gel electrophoresis. A variant allele named GOT1*2HR1 which seems to be identical with GOT1*2 was encountered in polymorphic frequency. Five kinds of rare variants, 3NG1, 4NG1, 5NG1, 6HR1, and 7NG1 were encountered in a total of 109 children. Except for 7NG1 for which complete family study was unable, family studies confirmed the genetic nature of these rare variants, since for all instances in which both parents could be examined, one of the parents exhibited the same variant as that of their child. Thermostability profiles of these six variants were normal. The enzyme activities of five were decreased, while the value of one was normal compared to that of GOT1 1. (author)

A low-frequency inactivating AKT2 variant enriched in the Finnish population is associated with fasting insulin levels and type 2 diabetes risk

Science.gov (United States)

Grarup, Niels; Rivas, Manuel A; Mahajan, Anubha; Locke, Adam E; Cingolani, Pablo; Pers, Tune H; Viñuela, Ana; Brown, Andrew A; Wu, Ying; Flannick, Jason; Fuchsberger, Christian; Gamazon, Eric R; Gaulton, Kyle J; Im, Hae Kyung; Teslovich, Tanya M; Blackwell, Thomas W; Bork-Jensen, Jette; Burtt, Noël P; Chen, Yuhui; Green, Todd; Hartl, Christopher; Kang, Hyun Min; Kumar, Ashish; Ladenvall, Claes; Ma, Clement; Moutsianas, Loukas; Pearson, Richard D; Perry, John R B; Rayner, N William; Robertson, Neil R; Scott, Laura J; van de Bunt, Martijn; Eriksson, Johan G; Jula, Antti; Koskinen, Seppo; Lehtimäki, Terho; Palotie, Aarno; Raitakari, Olli T; Jacobs, Suzanne BR; Wessel, Jennifer; Chu, Audrey Y; Scott, Robert A; Goodarzi, Mark O; Blancher, Christine; Buck, Gemma; Buck, David; Chines, Peter S; Gabriel, Stacey; Gjesing, Anette P; Groves, Christopher J; Hollensted, Mette; Huyghe, Jeroen R; Jackson, Anne U; Jun, Goo; Justesen, Johanne Marie; Mangino, Massimo; Murphy, Jacquelyn; Neville, Matt; Onofrio, Robert; Small, Kerrin S; Stringham, Heather M; Trakalo, Joseph; Banks, Eric; Carey, Jason; Carneiro, Mauricio O; DePristo, Mark; Farjoun, Yossi; Fennell, Timothy; Goldstein, Jacqueline I; Grant, George; de Angelis, Martin Hrabé; Maguire, Jared; Neale, Benjamin M; Poplin, Ryan; Purcell, Shaun; Schwarzmayr, Thomas; Shakir, Khalid; Smith, Joshua D; Strom, Tim M; Wieland, Thomas; Lindstrom, Jaana; Brandslund, Ivan; Christensen, Cramer; Surdulescu, Gabriela L; Lakka, Timo A; Doney, Alex S F; Nilsson, Peter; Wareham, Nicholas J; Langenberg, Claudia; Varga, Tibor V; Franks, Paul W; Rolandsson, Olov; Rosengren, Anders H; Farook, Vidya S; Thameem, Farook; Puppala, Sobha; Kumar, Satish; Lehman, Donna M; Jenkinson, Christopher P; Curran, Joanne E; Hale, Daniel Esten; Fowler, Sharon P; Arya, Rector; DeFronzo, Ralph A; Abboud, Hanna E; Syvänen, Ann-Christine; Hicks, Pamela J; Palmer, Nicholette D; Ng, Maggie C Y; Bowden, Donald W; Freedman, Barry I; Esko, Tõnu; Mägi, Reedik; Milani, Lili; Mihailov, Evelin; Metspalu, Andres; Narisu, Narisu; Kinnunen, Leena; Bonnycastle, Lori L; Swift, Amy; Pasko, Dorota; Wood, Andrew R; Fadista, João; Pollin, Toni I; Barzilai, Nir; Atzmon, Gil; Glaser, Benjamin; Thorand, Barbara; Strauch, Konstantin; Peters, Annette; Roden, Michael; Müller-Nurasyid, Martina; Liang, Liming; Kriebel, Jennifer; Illig, Thomas; Grallert, Harald; Gieger, Christian; Meisinger, Christa; Lannfelt, Lars; Musani, Solomon K; Griswold, Michael; Taylor, Herman A; Wilson, Gregory; Correa, Adolfo; Oksa, Heikki; Scott, William R; Afzal, Uzma; Tan, Sian-Tsung; Loh, Marie; Chambers, John C; Sehmi, Jobanpreet; Kooner, Jaspal Singh; Lehne, Benjamin; Cho, Yoon Shin; Lee, Jong-Young; Han, Bok-Ghee; Käräjämäki, Annemari; Qi, Qibin; Qi, Lu; Huang, Jinyan; Hu, Frank B; Melander, Olle; Orho-Melander, Marju; Below, Jennifer E; Aguilar, David; Wong, Tien Yin; Liu, Jianjun; Khor, Chiea-Chuen; Chia, Kee Seng; Lim, Wei Yen; Cheng, Ching-Yu; Chan, Edmund; Tai, E Shyong; Aung, Tin; Linneberg, Allan; Isomaa, Bo; Meitinger, Thomas; Tuomi, Tiinamaija; Hakaste, Liisa; Kravic, Jasmina; Jørgensen, Marit E; Lauritzen, Torsten; Deloukas, Panos; Stirrups, Kathleen E; Owen, Katharine R; Farmer, Andrew J; Frayling, Timothy M; O'Rahilly, Stephen P; Walker, Mark; Levy, Jonathan C; Hodgkiss, Dylan; Hattersley, Andrew T; Kuulasmaa, Teemu; Stančáková, Alena; Barroso, Inês; Bharadwaj, Dwaipayan; Chan, Juliana; Chandak, Giriraj R; Daly, Mark J; Donnelly, Peter J; Ebrahim, Shah B; Elliott, Paul; Fingerlin, Tasha; Froguel, Philippe; Hu, Cheng; Jia, Weiping; Ma, Ronald C W; McVean, Gilean; Park, Taesung; Prabhakaran, Dorairaj; Sandhu, Manjinder; Scott, James; Sladek, Rob; Tandon, Nikhil; Teo, Yik Ying; Zeggini, Eleftheria; Watanabe, Richard M; Koistinen, Heikki A; Kesaniemi, Y Antero; Uusitupa, Matti; Spector, Timothy D; Salomaa, Veikko; Rauramaa, Rainer; Palmer, Colin N A; Prokopenko, Inga; Morris, Andrew D; Bergman, Richard N; Collins, Francis S; Lind, Lars; Ingelsson, Erik; Tuomilehto, Jaakko; Karpe, Fredrik; Groop, Leif; Jørgensen, Torben; Hansen, Torben; Pedersen, Oluf; Kuusisto, Johanna; Abecasis, Gonçalo; Bell, Graeme I; Blangero, John; Cox, Nancy J; Duggirala, Ravindranath; Seielstad, Mark; Wilson, James G; Dupuis, Josee; Ripatti, Samuli; Hanis, Craig L; Florez, Jose C; Mohlke, Karen L; Meigs, James B; Laakso, Markku; Morris, Andrew P; Boehnke, Michael; Altshuler, David; McCarthy, Mark I; Gloyn, Anna L; Lindgren, Cecilia M

2017-01-01

To identify novel coding association signals and facilitate characterization of mechanisms influencing glycemic traits and type 2 diabetes risk, we analyzed 109,215 variants derived from exome array genotyping together with an additional 390,225 variants from exome sequence in up to 39,339 normoglycemic individuals from five ancestry groups. We identified a novel association between the coding variant (p.Pro50Thr) in AKT2 and fasting insulin, a gene in which rare fully penetrant mutations are causal for monogenic glycemic disorders. The low-frequency allele is associated with a 12% increase in fasting plasma insulin (FI) levels. This variant is present at 1.1% frequency in Finns but virtually absent in individuals from other ancestries. Carriers of the FI-increasing allele had increased 2-hour insulin values, decreased insulin sensitivity, and increased risk of type 2 diabetes (odds ratio=1.05). In cellular studies, the AKT2-Thr50 protein exhibited a partial loss of function. We extend the allelic spectrum for coding variants in AKT2 associated with disorders of glucose homeostasis and demonstrate bidirectional effects of variants within the pleckstrin homology domain of AKT2. PMID:28341696

A Low-Frequency Inactivating AKT2 Variant Enriched in the Finnish Population Is Associated With Fasting Insulin Levels and Type 2 Diabetes Risk.

Science.gov (United States)

Manning, Alisa; Highland, Heather M; Gasser, Jessica; Sim, Xueling; Tukiainen, Taru; Fontanillas, Pierre; Grarup, Niels; Rivas, Manuel A; Mahajan, Anubha; Locke, Adam E; Cingolani, Pablo; Pers, Tune H; Viñuela, Ana; Brown, Andrew A; Wu, Ying; Flannick, Jason; Fuchsberger, Christian; Gamazon, Eric R; Gaulton, Kyle J; Im, Hae Kyung; Teslovich, Tanya M; Blackwell, Thomas W; Bork-Jensen, Jette; Burtt, Noël P; Chen, Yuhui; Green, Todd; Hartl, Christopher; Kang, Hyun Min; Kumar, Ashish; Ladenvall, Claes; Ma, Clement; Moutsianas, Loukas; Pearson, Richard D; Perry, John R B; Rayner, N William; Robertson, Neil R; Scott, Laura J; van de Bunt, Martijn; Eriksson, Johan G; Jula, Antti; Koskinen, Seppo; Lehtimäki, Terho; Palotie, Aarno; Raitakari, Olli T; Jacobs, Suzanne B R; Wessel, Jennifer; Chu, Audrey Y; Scott, Robert A; Goodarzi, Mark O; Blancher, Christine; Buck, Gemma; Buck, David; Chines, Peter S; Gabriel, Stacey; Gjesing, Anette P; Groves, Christopher J; Hollensted, Mette; Huyghe, Jeroen R; Jackson, Anne U; Jun, Goo; Justesen, Johanne Marie; Mangino, Massimo; Murphy, Jacquelyn; Neville, Matt; Onofrio, Robert; Small, Kerrin S; Stringham, Heather M; Trakalo, Joseph; Banks, Eric; Carey, Jason; Carneiro, Mauricio O; DePristo, Mark; Farjoun, Yossi; Fennell, Timothy; Goldstein, Jacqueline I; Grant, George; Hrabé de Angelis, Martin; Maguire, Jared; Neale, Benjamin M; Poplin, Ryan; Purcell, Shaun; Schwarzmayr, Thomas; Shakir, Khalid; Smith, Joshua D; Strom, Tim M; Wieland, Thomas; Lindstrom, Jaana; Brandslund, Ivan; Christensen, Cramer; Surdulescu, Gabriela L; Lakka, Timo A; Doney, Alex S F; Nilsson, Peter; Wareham, Nicholas J; Langenberg, Claudia; Varga, Tibor V; Franks, Paul W; Rolandsson, Olov; Rosengren, Anders H; Farook, Vidya S; Thameem, Farook; Puppala, Sobha; Kumar, Satish; Lehman, Donna M; Jenkinson, Christopher P; Curran, Joanne E; Hale, Daniel Esten; Fowler, Sharon P; Arya, Rector; DeFronzo, Ralph A; Abboud, Hanna E; Syvänen, Ann-Christine; Hicks, Pamela J; Palmer, Nicholette D; Ng, Maggie C Y; Bowden, Donald W; Freedman, Barry I; Esko, Tõnu; Mägi, Reedik; Milani, Lili; Mihailov, Evelin; Metspalu, Andres; Narisu, Narisu; Kinnunen, Leena; Bonnycastle, Lori L; Swift, Amy; Pasko, Dorota; Wood, Andrew R; Fadista, João; Pollin, Toni I; Barzilai, Nir; Atzmon, Gil; Glaser, Benjamin; Thorand, Barbara; Strauch, Konstantin; Peters, Annette; Roden, Michael; Müller-Nurasyid, Martina; Liang, Liming; Kriebel, Jennifer; Illig, Thomas; Grallert, Harald; Gieger, Christian; Meisinger, Christa; Lannfelt, Lars; Musani, Solomon K; Griswold, Michael; Taylor, Herman A; Wilson, Gregory; Correa, Adolfo; Oksa, Heikki; Scott, William R; Afzal, Uzma; Tan, Sian-Tsung; Loh, Marie; Chambers, John C; Sehmi, Jobanpreet; Kooner, Jaspal Singh; Lehne, Benjamin; Cho, Yoon Shin; Lee, Jong-Young; Han, Bok-Ghee; Käräjämäki, Annemari; Qi, Qibin; Qi, Lu; Huang, Jinyan; Hu, Frank B; Melander, Olle; Orho-Melander, Marju; Below, Jennifer E; Aguilar, David; Wong, Tien Yin; Liu, Jianjun; Khor, Chiea-Chuen; Chia, Kee Seng; Lim, Wei Yen; Cheng, Ching-Yu; Chan, Edmund; Tai, E Shyong; Aung, Tin; Linneberg, Allan; Isomaa, Bo; Meitinger, Thomas; Tuomi, Tiinamaija; Hakaste, Liisa; Kravic, Jasmina; Jørgensen, Marit E; Lauritzen, Torsten; Deloukas, Panos; Stirrups, Kathleen E; Owen, Katharine R; Farmer, Andrew J; Frayling, Timothy M; O'Rahilly, Stephen P; Walker, Mark; Levy, Jonathan C; Hodgkiss, Dylan; Hattersley, Andrew T; Kuulasmaa, Teemu; Stančáková, Alena; Barroso, Inês; Bharadwaj, Dwaipayan; Chan, Juliana; Chandak, Giriraj R; Daly, Mark J; Donnelly, Peter J; Ebrahim, Shah B; Elliott, Paul; Fingerlin, Tasha; Froguel, Philippe; Hu, Cheng; Jia, Weiping; Ma, Ronald C W; McVean, Gilean; Park, Taesung; Prabhakaran, Dorairaj; Sandhu, Manjinder; Scott, James; Sladek, Rob; Tandon, Nikhil; Teo, Yik Ying; Zeggini, Eleftheria; Watanabe, Richard M; Koistinen, Heikki A; Kesaniemi, Y Antero; Uusitupa, Matti; Spector, Timothy D; Salomaa, Veikko; Rauramaa, Rainer; Palmer, Colin N A; Prokopenko, Inga; Morris, Andrew D; Bergman, Richard N; Collins, Francis S; Lind, Lars; Ingelsson, Erik; Tuomilehto, Jaakko; Karpe, Fredrik; Groop, Leif; Jørgensen, Torben; Hansen, Torben; Pedersen, Oluf; Kuusisto, Johanna; Abecasis, Gonçalo; Bell, Graeme I; Blangero, John; Cox, Nancy J; Duggirala, Ravindranath; Seielstad, Mark; Wilson, James G; Dupuis, Josee; Ripatti, Samuli; Hanis, Craig L; Florez, Jose C; Mohlke, Karen L; Meigs, James B; Laakso, Markku; Morris, Andrew P; Boehnke, Michael; Altshuler, David; McCarthy, Mark I; Gloyn, Anna L; Lindgren, Cecilia M

2017-07-01

To identify novel coding association signals and facilitate characterization of mechanisms influencing glycemic traits and type 2 diabetes risk, we analyzed 109,215 variants derived from exome array genotyping together with an additional 390,225 variants from exome sequence in up to 39,339 normoglycemic individuals from five ancestry groups. We identified a novel association between the coding variant (p.Pro50Thr) in AKT2 and fasting plasma insulin (FI), a gene in which rare fully penetrant mutations are causal for monogenic glycemic disorders. The low-frequency allele is associated with a 12% increase in FI levels. This variant is present at 1.1% frequency in Finns but virtually absent in individuals from other ancestries. Carriers of the FI-increasing allele had increased 2-h insulin values, decreased insulin sensitivity, and increased risk of type 2 diabetes (odds ratio 1.05). In cellular studies, the AKT2-Thr50 protein exhibited a partial loss of function. We extend the allelic spectrum for coding variants in AKT2 associated with disorders of glucose homeostasis and demonstrate bidirectional effects of variants within the pleckstrin homology domain of AKT2 . © 2017 by the American Diabetes Association.

Pleiotropic Effects of Variants in Dementia Genes in Parkinson Disease

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Laura Ibanez

2018-04-01

Full Text Available Background: The prevalence of dementia in Parkinson disease (PD increases dramatically with advancing age, approaching 80% in patients who survive 20 years with the disease. Increasing evidence suggests clinical, pathological and genetic overlap between Alzheimer disease, dementia with Lewy bodies and frontotemporal dementia with PD. However, the contribution of the dementia-causing genes to PD risk, cognitive impairment and dementia in PD is not fully established.Objective: To assess the contribution of coding variants in Mendelian dementia-causing genes on the risk of developing PD and the effect on cognitive performance of PD patients.Methods: We analyzed the coding regions of the amyloid-beta precursor protein (APP, Presenilin 1 and 2 (PSEN1, PSEN2, and Granulin (GRN genes from 1,374 PD cases and 973 controls using pooled-DNA targeted sequence, human exome-chip and whole-exome sequencing (WES data by single variant and gene base (SKAT-O and burden tests analyses. Global cognitive function was assessed using the Mini-Mental State Examination (MMSE or the Montreal Cognitive Assessment (MoCA. The effect of coding variants in dementia-causing genes on cognitive performance was tested by multiple regression analysis adjusting for gender, disease duration, age at dementia assessment, study site and APOE carrier status.Results: Known AD pathogenic mutations in the PSEN1 (p.A79V and PSEN2 (p.V148I genes were found in 0.3% of all PD patients. There was a significant burden of rare, likely damaging variants in the GRN and PSEN1 genes in PD patients when compared with frequencies in the European population from the ExAC database. Multiple regression analysis revealed that PD patients carrying rare variants in the APP, PSEN1, PSEN2, and GRN genes exhibit lower cognitive tests scores than non-carrier PD patients (p = 2.0 × 10−4, independent of age at PD diagnosis, age at evaluation, APOE status or recruitment site.Conclusions: Pathogenic mutations in

TRPV6 alleles do not influence prostate cancer progression

OpenAIRE

Kessler, Thorsten; Wissenbach, Ulrich; Grobholz, Rainer; Flockerzi, Veit

2009-01-01

Abstract Background The transient receptor potential, subfamily V, member 6 (TRPV6) is a Ca2+ selective cation channel. Several studies have shown that TRPV6 transcripts are expressed in locally advanced prostatic adenocarcinoma, metastatic and androgen-insensitive prostatic lesions but are undetectable in healthy prostate tissue and benign prostatic hyperplasia. Two allelic variants of the human trpv6 gene have been identified which are transcribed into two independent mRNAs, TRPV6a and TRPV...

Apolipoprotein E4 Allele and Gait Performance in Mild Cognitive Impairment: Results From the Gait and Brain Study.

Science.gov (United States)

Sakurai, Ryota; Montero-Odasso, Manuel

2017-11-09

The apolipoprotein E polymorphism ε4 allele (ApoE4) and gait impairment are both known risk factors for developing cognitive decline and dementia. However, it is unclear the interrelationship between these factors, particularly among older adults with mild cognitive impairment (MCI) who are considered as prodromal for Alzheimer's disease. This study aimed to determine whether ApoE4 carrier individuals with MCI may experience greater impairment in gait performance. Fifty-six older adults with MCI from the "Gait and Brain Study" who were identified as either ApoE4 carriers (n = 20) or non-ApoE4 carriers (n = 36) with 1 year of follow-up were included. Gait variability, the main outcome variable, was assessed as stride time variability with an electronic walkway. Additional gait variables and cognitive performance (mini-mental state examination [MMSE] and Montreal Cognitive Assessment [MoCA]) were also recorded. Covariates included age, sex, education level, body mass index, and number of comorbidities. Baseline characteristics were similar for both groups. Repeated measures analysis of covariance showed that gait stride time and stride length variabilities significantly increased in ApoE4 carriers but was maintained in the non-ApoE4 carriers. Similarly, ApoE4 carriers showed greater decrease in MMSE score at follow-up. In this sample of older adults with MCI, the presence of at least one copy of ApoE4 was associated with the development of both increased gait variability and cognitive decline during 1 year of follow-up. ApoE4 genotype might be considered as a potential mediator of decline in mobility function in MCI; future studies with larger samples are needed to confirm our preliminary findings. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Identification of Inherited Retinal Disease-Associated Genetic Variants in 11 Candidate Genes.

Science.gov (United States)

Astuti, Galuh D N; van den Born, L Ingeborgh; Khan, M Imran; Hamel, Christian P; Bocquet, Béatrice; Manes, Gaël; Quinodoz, Mathieu; Ali, Manir; Toomes, Carmel; McKibbin, Martin; El-Asrag, Mohammed E; Haer-Wigman, Lonneke; Inglehearn, Chris F; Black, Graeme C M; Hoyng, Carel B; Cremers, Frans P M; Roosing, Susanne

2018-01-10

Inherited retinal diseases (IRDs) display an enormous genetic heterogeneity. Whole exome sequencing (WES) recently identified genes that were mutated in a small proportion of IRD cases. Consequently, finding a second case or family carrying pathogenic variants in the same candidate gene often is challenging. In this study, we searched for novel candidate IRD gene-associated variants in isolated IRD families, assessed their causality, and searched for novel genotype-phenotype correlations. Whole exome sequencing was performed in 11 probands affected with IRDs. Homozygosity mapping data was available for five cases. Variants with minor allele frequencies ≤ 0.5% in public databases were selected as candidate disease-causing variants. These variants were ranked based on their: (a) presence in a gene that was previously implicated in IRD; (b) minor allele frequency in the Exome Aggregation Consortium database (ExAC); (c) in silico pathogenicity assessment using the combined annotation dependent depletion (CADD) score; and (d) interaction of the corresponding protein with known IRD-associated proteins. Twelve unique variants were found in 11 different genes in 11 IRD probands. Novel autosomal recessive and dominant inheritance patterns were found for variants in Small Nuclear Ribonucleoprotein U5 Subunit 200 ( SNRNP200 ) and Zinc Finger Protein 513 ( ZNF513 ), respectively. Using our pathogenicity assessment, a variant in DEAH-Box Helicase 32 ( DHX32 ) was the top ranked novel candidate gene to be associated with IRDs, followed by eight medium and lower ranked candidate genes. The identification of candidate disease-associated sequence variants in 11 single families underscores the notion that the previously identified IRD-associated genes collectively carry > 90% of the defects implicated in IRDs. To identify multiple patients or families with variants in the same gene and thereby provide extra proof for pathogenicity, worldwide data sharing is needed.

Functional non-synonymous variants of ABCG2 and gout risk.

Science.gov (United States)

Stiburkova, Blanka; Pavelcova, Katerina; Zavada, Jakub; Petru, Lenka; Simek, Pavel; Cepek, Pavel; Pavlikova, Marketa; Matsuo, Hirotaka; Merriman, Tony R; Pavelka, Karel

2017-11-01

Common dysfunctional variants of ATP binding cassette subfamily G member 2 (Junior blood group) (ABCG2), a high-capacity urate transporter gene, that result in decreased urate excretion are major causes of hyperuricemia and gout. In the present study, our objective was to determine the frequency and effect on gout of common and rare non-synonymous and other functional allelic variants in the ABCG2 gene. The main cohort recruited from the Czech Republic consisted of 145 gout patients; 115 normouricaemic controls were used for comparison. We amplified, directly sequenced and analysed 15 ABCG2 exons. The associations between genetic variants and clinical phenotype were analysed using the t-test, Fisher's exact test and a logistic and linear regression approach. Data from a New Zealand Polynesian sample set and the UK Biobank were included for the p.V12M analysis. In the ABCG2 gene, 18 intronic (one dysfunctional splicing) and 11 exonic variants were detected: 9 were non-synonymous (2 common, 7 rare including 1 novel), namely p.V12M, p.Q141K, p.R147W, p.T153M, p.F373C, p.T434M, p.S476P, p.D620N and p.K360del. The p.Q141K (rs2231142) variant had a significantly higher minor allele frequency (0.23) in the gout patients compared with the European-origin population (0.09) and was significantly more common among gout patients than among normouricaemic controls (odds ratio = 3.26, P gout (42 vs 48 years, P = 0.0143) and a greater likelihood of a familial history of gout (41% vs 27%, odds ratio = 1.96, P = 0.053). In a meta-analysis p.V12M exerted a protective effect from gout (P gout. Non-synonymous allelic variants of ABCG2 had a significant effect on earlier onset of gout and the presence of a familial gout history. ABCG2 should thus be considered a common and significant risk factor for gout. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Identifying genetic variants that affect viability in large cohorts.

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Hakhamanesh Mostafavi

2017-09-01

Full Text Available A number of open questions in human evolutionary genetics would become tractable if we were able to directly measure evolutionary fitness. As a step towards this goal, we developed a method to examine whether individual genetic variants, or sets of genetic variants, currently influence viability. The approach consists in testing whether the frequency of an allele varies across ages, accounting for variation in ancestry. We applied it to the Genetic Epidemiology Research on Adult Health and Aging (GERA cohort and to the parents of participants in the UK Biobank. Across the genome, we found only a few common variants with large effects on age-specific mortality: tagging the APOE ε4 allele and near CHRNA3. These results suggest that when large, even late-onset effects are kept at low frequency by purifying selection. Testing viability effects of sets of genetic variants that jointly influence 1 of 42 traits, we detected a number of strong signals. In participants of the UK Biobank of British ancestry, we found that variants that delay puberty timing are associated with a longer parental life span (P~6.2 × 10-6 for fathers and P~2.0 × 10-3 for mothers, consistent with epidemiological studies. Similarly, variants associated with later age at first birth are associated with a longer maternal life span (P~1.4 × 10-3. Signals are also observed for variants influencing cholesterol levels, risk of coronary artery disease (CAD, body mass index, as well as risk of asthma. These signals exhibit consistent effects in the GERA cohort and among participants of the UK Biobank of non-British ancestry. We also found marked differences between males and females, most notably at the CHRNA3 locus, and variants associated with risk of CAD and cholesterol levels. Beyond our findings, the analysis serves as a proof of principle for how upcoming biomedical data sets can be used to learn about selection effects in contemporary humans.

Genomic Features That Predict Allelic Imbalance in Humans Suggest Patterns of Constraint on Gene Expression Variation

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Fédrigo, Olivier; Haygood, Ralph; Mukherjee, Sayan; Wray, Gregory A.

2009-01-01

Variation in gene expression is an important contributor to phenotypic diversity within and between species. Although this variation often has a genetic component, identification of the genetic variants driving this relationship remains challenging. In particular, measurements of gene expression usually do not reveal whether the genetic basis for any observed variation lies in cis or in trans to the gene, a distinction that has direct relevance to the physical location of the underlying genetic variant, and which may also impact its evolutionary trajectory. Allelic imbalance measurements identify cis-acting genetic effects by assaying the relative contribution of the two alleles of a cis-regulatory region to gene expression within individuals. Identification of patterns that predict commonly imbalanced genes could therefore serve as a useful tool and also shed light on the evolution of cis-regulatory variation itself. Here, we show that sequence motifs, polymorphism levels, and divergence levels around a gene can be used to predict commonly imbalanced genes in a human data set. Reduction of this feature set to four factors revealed that only one factor significantly differentiated between commonly imbalanced and nonimbalanced genes. We demonstrate that these results are consistent between the original data set and a second published data set in humans obtained using different technical and statistical methods. Finally, we show that variation in the single allelic imbalance-associated factor is partially explained by the density of genes in the region of a target gene (allelic imbalance is less probable for genes in gene-dense regions), and, to a lesser extent, the evenness of expression of the gene across tissues and the magnitude of negative selection on putative regulatory regions of the gene. These results suggest that the genomic distribution of functional cis-regulatory variants in the human genome is nonrandom, perhaps due to local differences in evolutionary

Frequency of interleukin 28B rs12979860 C>T variants in Filipino patients chronically infected with hepatitis B virus.

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Baclig, Michael O; Reyes, Karen G; Mapua, Cynthia A; Gopez-Cervantes, Juliet; Natividad, Filipinas F

2015-03-01

Hepatitis B virus (HBV) is one of the most prevalent viral infections worldwide. Nearly 400 million individuals are chronic carriers of HBV. The aim of the present study was to determine the frequency of human interleukin 28B (IL28B) variants among treatment naive Filipino patients clinically diagnosed with chronic hepatitis B (CHB), and to compare the IL28B frequency distribution with various ethnic populations. Fifty-seven CHB patients and 43 normal controls were enrolled in this study. Real-time PCR was performed using the TaqMan genotyping assay for IL28B rs12979860. The allelic frequencies among normal controls were 0.94 and 0.06 for the IL28B rs12979860 C and T alleles, respectively. Eighty-eight percent were identified as homozygous for the IL28B C/C genotype and 12% were identified as heterozygous for the IL28B C/T genotype. Among CHB patients, the allelic frequencies were 0.90 for the IL28B C allele and 0.10 for the IL28B T allele. No IL28B T/T genotype was observed between the two groups. No significant difference in the distribution of IL28B genotypes was observed between normal controls and CHB patients. Allelic frequencies of IL28B among Filipinos were similar with other Asian populations but significantly different from Caucasians. The frequency of rs12979860 C>T variants among Filipino CHB patients has not yet been reported. These data provided new insight into the geographical frequency distribution of IL28B variants. Further studies are needed to determine the possible association between IL28B variants and response to pegylated-interferon-α plus ribavirin combination therapy among Filipino patients chronically infected with HBV.

Identification of Candidate Gene Variants in Korean MODY Families by Whole-Exome Sequencing.

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Shim, Ye Jee; Kim, Jung Eun; Hwang, Su-Kyeong; Choi, Bong Seok; Choi, Byung Ho; Cho, Eun-Mi; Jang, Kyoung Mi; Ko, Cheol Woo

2015-01-01

To date, 13 genes causing maturity-onset diabetes of the young (MODY) have been identified. However, there is a big discrepancy in the genetic locus between Asian and Caucasian patients with MODY. Thus, we conducted whole-exome sequencing in Korean MODY families to identify causative gene variants. Six MODY probands and their family members were included. Variants in the dbSNP135 and TIARA databases for Koreans and the variants with minor allele frequencies >0.5% of the 1000 Genomes database were excluded. We selected only the functional variants (gain of stop codon, frameshifts and nonsynonymous single-nucleotide variants) and conducted a case-control comparison in the family members. The selected variants were scanned for the previously introduced gene set implicated in glucose metabolism. Three variants c.620C>T:p.Thr207Ile in PTPRD, c.559C>G:p.Gln187Glu in SYT9, and c.1526T>G:p.Val509Gly in WFS1 were respectively identified in 3 families. We could not find any disease-causative alleles of known MODY 1-13 genes. Based on the predictive program, Thr207Ile in PTPRD was considered pathogenic. Whole-exome sequencing is a valuable method for the genetic diagnosis of MODY. Further evaluation is necessary about the role of PTPRD, SYT9 and WFS1 in normal insulin release from pancreatic beta cells. © 2015 S. Karger AG, Basel.

New allelic variant of autosomal recessive hereditary motor and sensory neuropathy type 2S resulted from mutations in gene IGHMBP2

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E. L. Dadali

2016-01-01

Full Text Available Hereditary motor and sensory neuropathy (HMSN, Charcot–Marie–Tooth disease is a group of genetically heterogeneous disorders with more than 80 genes linked to different phenotypes, including IGHMBP2 gene responsible for HMSN type 2S (OMIM 616155. Until recently, mutations in IGHMBP2 were exclusively associated with neonatal distal spinal muscular atrophy with respiratory distress (SMARD1, OMIM 604320. A case report presents a boy with infant onset decreased distal muscle tone and weakness, distal wasting and deformation in legs and hands, areflexia and decreased sensation without respiratory involvement; at age seven he had severe fixed kypho-scoliosis. EMG revealed signs distal axonal neuropathy. The exsome sequencing confirmed the allelic variant of two compound heterozygous mutations in gene IGHMBP2: known missens mutation с.1616С>Т (р.Ser539Leu in exone 11 and a novel deletion с.2601_2602delGA in exone 13. The diagnosis of infant HMSN type 2S was confirmed. The phenotype of HMSN type 2S and its diagnostics differences between SMARD1 are discussed.

Annotating pathogenic non-coding variants in genic regions.

Science.gov (United States)

Gelfman, Sahar; Wang, Quanli; McSweeney, K Melodi; Ren, Zhong; La Carpia, Francesca; Halvorsen, Matt; Schoch, Kelly; Ratzon, Fanni; Heinzen, Erin L; Boland, Michael J; Petrovski, Slavé; Goldstein, David B

2017-08-09

Identifying the underlying causes of disease requires accurate interpretation of genetic variants. Current methods ineffectively capture pathogenic non-coding variants in genic regions, resulting in overlooking synonymous and intronic variants when searching for disease risk. Here we present the Transcript-inferred Pathogenicity (TraP) score, which uses sequence context alterations to reliably identify non-coding variation that causes disease. High TraP scores single out extremely rare variants with lower minor allele frequencies than missense variants. TraP accurately distinguishes known pathogenic and benign variants in synonymous (AUC = 0.88) and intronic (AUC = 0.83) public datasets, dismissing benign variants with exceptionally high specificity. TraP analysis of 843 exomes from epilepsy family trios identifies synonymous variants in known epilepsy genes, thus pinpointing risk factors of disease from non-coding sequence data. TraP outperforms leading methods in identifying non-coding variants that are pathogenic and is therefore a valuable tool for use in gene discovery and the interpretation of personal genomes.While non-coding synonymous and intronic variants are often not under strong selective constraint, they can be pathogenic through affecting splicing or transcription. Here, the authors develop a score that uses sequence context alterations to predict pathogenicity of synonymous and non-coding genetic variants, and provide a web server of pre-computed scores.

QuASAR: quantitative allele-specific analysis of reads.

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Harvey, Chris T; Moyerbrailean, Gregory A; Davis, Gordon O; Wen, Xiaoquan; Luca, Francesca; Pique-Regi, Roger

2015-04-15

Expression quantitative trait loci (eQTL) studies have discovered thousands of genetic variants that regulate gene expression, enabling a better understanding of the functional role of non-coding sequences. However, eQTL studies are costly, requiring large sample sizes and genome-wide genotyping of each sample. In contrast, analysis of allele-specific expression (ASE) is becoming a popular approach to detect the effect of genetic variation on gene expression, even within a single individual. This is typically achieved by counting the number of RNA-seq reads matching each allele at heterozygous sites and testing the null hypothesis of a 1:1 allelic ratio. In principle, when genotype information is not readily available, it could be inferred from the RNA-seq reads directly. However, there are currently no existing methods that jointly infer genotypes and conduct ASE inference, while considering uncertainty in the genotype calls. We present QuASAR, quantitative allele-specific analysis of reads, a novel statistical learning method for jointly detecting heterozygous genotypes and inferring ASE. The proposed ASE inference step takes into consideration the uncertainty in the genotype calls, while including parameters that model base-call errors in sequencing and allelic over-dispersion. We validated our method with experimental data for which high-quality genotypes are available. Results for an additional dataset with multiple replicates at different sequencing depths demonstrate that QuASAR is a powerful tool for ASE analysis when genotypes are not available. http://github.com/piquelab/QuASAR. fluca@wayne.edu or rpique@wayne.edu Supplementary Material is available at Bioinformatics online. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

The enzymatic activities of brain catechol-O-methyltransferase (COMT) and methionine sulphoxide reductase are correlated in a COMT Val/Met allele-dependent fashion.

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Moskovitz, Jackob; Walss-Bass, Consuelo; Cruz, Dianne A; Thompson, Peter M; Hairston, Jenaqua; Bortolato, Marco

2015-12-01

The enzyme catechol-O-methyltransferase (COMT) plays a primary role in the metabolism of catecholamine neurotransmitters and is implicated in the modulation of cognitive and emotional responses. The best characterized single nucleotide polymorphism (SNP) of the COMT gene consists of a valine (Val)-to-methionine (Met) substitution at codon 108/158. The Met-containing variant confers a marked reduction in COMT catalytic activity. We recently showed that the activity of recombinant COMT is positively regulated by the enzyme Met sulphoxide reductase (MSR), which counters the oxidation of Met residues of proteins. The current study was designed to assess whether brain COMT activity may be correlated to MSR in an allele-dependent fashion. COMT and MSR activities were measured from post-mortem samples of prefrontal cortices, striata and cerebella of 32 subjects by using catechol and dabsyl-Met sulphoxide as substrates, respectively. Allelic discrimination of COMT Val(108/185) Met SNP was performed using the Taqman 5'nuclease assay. Our studies revealed that, in homozygous carriers of Met, but not Val alleles, the activity of COMT and MSR was significantly correlated throughout all tested brain regions. These results suggest that the reduced enzymatic activity of Met-containing COMT may be secondary to Met sulphoxidation and point to MSR as a key molecular determinant for the modulation of COMT activity. © 2015 British Neuropathological Society.

Distortion of maternal-fetal angiotensin II type 1 receptor allele transmission in pre-eclampsia.

Science.gov (United States)

Morgan, L; Crawshaw, S; Baker, P N; Brookfield, J F; Broughton Pipkin, F; Kalsheker, N

1998-01-01

OBJECTIVE: To investigate the fetal angiotensin II type 1 receptor genotype in pre-eclampsia. DESIGN: Case-control study. POPULATION: Forty-one maternal-fetal pairs from pre-eclamptic pregnancies and 80 maternal-fetal pairs from normotensive pregnancies. METHODS: Maternal and fetal DNA was genotyped at three diallelic polymorphisms, at nucleotides 573, 1062, and 1166, in the coding exon of the angiotensin II type 1 receptor gene, and at a dinucleotide repeat polymorphism in its 3' flanking region. RESULTS: Allele and genotype frequencies at the four polymorphic regions investigated did not differ between pre-eclamptic and normotensive groups, in either fetal or maternal samples. Mothers heterozygous for the dinucleotide repeat allele designated A4 transmitted this allele to the fetus in 15 of 18 informative pre-eclamptic pregnancies and in eight of 26 normotensive pregnancies. This was greater than the expected probability in pre-eclamptic pregnancies (p=0.04) and less than expected in normotensive pregnancies (p<0.005). The 573T variant, which is in partial linkage disequilibrium with the A4 allele, showed a similar distortion of maternal-fetal transmission. CONCLUSION: Angiotensin II type 1 receptor gene expression in the fetus may contribute to the aetiology of pre-eclampsia. It is unclear whether susceptibility is conferred by the fetal genotype acting alone, or by allele sharing by mother and fetus. Possible mechanisms for the effect of the angiotensin II type 1 receptor gene are suggested by the association of the 573T variant with low levels of surface receptor expression on platelets. If receptor expression is similarly genetically determined in the placenta, responsiveness to angiotensin II may be affected, with the potential to influence placentation or placental prostaglandin secretion. PMID:9719367

Allele-Selective Transcriptome Recruitment to Polysomes Primed for Translation: Protein-Coding and Noncoding RNAs, and RNA Isoforms.

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Roshan Mascarenhas

Full Text Available mRNA translation into proteins is highly regulated, but the role of mRNA isoforms, noncoding RNAs (ncRNAs, and genetic variants remains poorly understood. mRNA levels on polysomes have been shown to correlate well with expressed protein levels, pointing to polysomal loading as a critical factor. To study regulation and genetic factors of protein translation we measured levels and allelic ratios of mRNAs and ncRNAs (including microRNAs in lymphoblast cell lines (LCL and in polysomal fractions. We first used targeted assays to measure polysomal loading of mRNA alleles, confirming reported genetic effects on translation of OPRM1 and NAT1, and detecting no effect of rs1045642 (3435C>T in ABCB1 (MDR1 on polysomal loading while supporting previous results showing increased mRNA turnover of the 3435T allele. Use of high-throughput sequencing of complete transcript profiles (RNA-Seq in three LCLs revealed significant differences in polysomal loading of individual RNA classes and isoforms. Correlated polysomal distribution between protein-coding and non-coding RNAs suggests interactions between them. Allele-selective polysome recruitment revealed strong genetic influence for multiple RNAs, attributable either to differential expression of RNA isoforms or to differential loading onto polysomes, the latter defining a direct genetic effect on translation. Genes identified by different allelic RNA ratios between cytosol and polysomes were enriched with published expression quantitative trait loci (eQTLs affecting RNA functions, and associations with clinical phenotypes. Polysomal RNA-Seq combined with allelic ratio analysis provides a powerful approach to study polysomal RNA recruitment and regulatory variants affecting protein translation.

Common Genetic Variants Found in HLA and KIR Immune Genes in Autism Spectrum Disorder

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Anthony R Torres

2016-10-01

Full Text Available The common variant - common disease hypothesis was proposed to explain diseases with strong inheritance. This model suggests that a genetic disease is the result of the combination of several common genetic variants. Common genetic variants are described as a 5% frequency differential between diseased versus matched control populations. This theory was recently supported by an epidemiology paper stating that about 50% of genetic risk for autism resides in common variants. However, rare variants, rather than common variants, have been found in numerous genome wide genetic studies and many have concluded that the common variant—common disease hypothesis is incorrect. One interpretation is that rare variants are major contributors to genetic diseases and autism involves the interaction of many rare variants, especially in the brain. It is obvious there is much yet to be learned about autism genetics.Evidence has been mounting over the years indicating immune involvement in autism, particularly the HLA genes on chromosome 6 and KIR genes on chromosome 19. These two large multigene complexes have important immune functions and have been shown to interact to eliminate unwanted virally infected and malignant cells. HLA proteins have important functions in antigen presentation in adaptive immunity and specific epitopes on HLA class I proteins act as cognate ligands for KIR receptors in innate immunity. Data suggests that HLA alleles and KIR activating genes/haplotypes are common variants in different autism populations. For example, class I allele (HLA-A2 and HLA-G 14bp-indel frequencies are significantly increased by more than 5% over control populations (Table2. The HLA-DR4 Class II and shared epitope frequencies are significantly above the control populations (Table 2. Three activating KIR genes: 3DS1, 2DS1 and 2DS2 have increased frequencies of 15%, 22% and 14% in autism populations, respectively. There is a 6% increase in total activating KIR

The prevalence of PAI-1 4G/5G gene variant in Serbian population

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Đorđević Valentina

2013-01-01

Full Text Available Introduction: Plasminogen activator inhibitor 1 (PAI-1 has a major role in inhibition of firinolysis and normal haemostasis. The presence of the PAI-1 4G/4G genotype leads to increased expression of PAI-1. High blood level of PAI-1 is associated with many diseases such as thrombosis, cerebral insult, myocardial infarction, pregnancy loss, preeclampsia, insulin resistance, type 2 diabetes, breast cancer and asthma. In this study, the prevalence of PAI-1 4G/5G gene variant was determined in healthy subjects from Serbian population. Methods: The study was carried out in a group of 210 healthy subjects (105 women and 105 men. The presence of PAI-1 4G/5G gene variant was detected by PCR-RFLP analysis. Results: The prevalence of PAI-1 4G/4G genotype was 34.76% and it was increased compared to PAI-1 5G/5G genotype (19.05%. The most frequent was PAI-1 4G/5G genotype (46.19%. Allelic frequency for 4G allele was higher (0.58 compared to 5G allele (0.42. Conclusions: The prevalence of PAI-1 4G/5G gene variant in Serbian population is similar to the neighboring populations. Results of this study represent the first data for Serbian population. This study could be useful for further research where the role of PAI-1 4G/5G gene variant will be assessed in the pathogenesis of many diseases.

Coronary artery disease-associated genetic variants and biomarkers of inflammation

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Christiansen, Morten Krogh; Larsen, Sanne Bøjet; Nyegaard, Mette

2017-01-01

score was calculated to assess the combined risk associated with all the genetic variants. A multiple linear regression model was used to assess associations between the genetic risk score, single SNPs, and the five inflammatory biomarkers. RESULTS:The minor allele (G) (CAD risk allele) of rs2075650......INTRODUCTION:Genetic constitution and inflammation both contribute to development of coronary artery disease (CAD). Several CAD-associated single-nucleotide polymorphisms (SNPs) have recently been identified, but their functions are largely unknown. We investigated the associations between CAD...

Birth cohort differences in the prevalence of longevity-associated variants in APOE and FOXO3A in Danish long-lived individuals

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Nygaard, Marianne; Lindahl-Jacobsen, Rune; Soerensen, Mette

2014-01-01

a recessive model, this negative trend is significant in 95+ year old individuals homozygous for the APOE ε4 allele (P=0.026) or for the FOXO3A rs7762395 minor allele (P=0.048). For the APOE ε4 allele, the significance is further strengthened when restricting to women (P=0.006). Supportive, but non......-significant, trends are found for two of the three tested variants in individuals older than 100years. Altogether, this indicates that cohort differences in selection pressure on survival to the highest ages are reflected in the prevalence of longevity gene variants. Although the effect seems to be moderate, our...

Genome-wide meta-analysis of common variant differences between men and women

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Boraska, Vesna; Jerončić, Ana; Colonna, Vincenza; Southam, Lorraine; Nyholt, Dale R.; William Rayner, Nigel; Perry, John R.B.; Toniolo, Daniela; Albrecht, Eva; Ang, Wei; Bandinelli, Stefania; Barbalic, Maja; Barroso, Inês; Beckmann, Jacques S.; Biffar, Reiner; Boomsma, Dorret; Campbell, Harry; Corre, Tanguy; Erdmann, Jeanette; Esko, Tõnu; Fischer, Krista; Franceschini, Nora; Frayling, Timothy M.; Girotto, Giorgia; Gonzalez, Juan R.; Harris, Tamara B.; Heath, Andrew C.; Heid, Iris M.; Hoffmann, Wolfgang; Hofman, Albert; Horikoshi, Momoko; Hua Zhao, Jing; Jackson, Anne U.; Hottenga, Jouke-Jan; Jula, Antti; Kähönen, Mika; Khaw, Kay-Tee; Kiemeney, Lambertus A.; Klopp, Norman; Kutalik, Zoltán; Lagou, Vasiliki; Launer, Lenore J.; Lehtimäki, Terho; Lemire, Mathieu; Lokki, Marja-Liisa; Loley, Christina; Luan, Jian'an; Mangino, Massimo; Mateo Leach, Irene; Medland, Sarah E.; Mihailov, Evelin; Montgomery, Grant W.; Navis, Gerjan; Newnham, John; Nieminen, Markku S.; Palotie, Aarno; Panoutsopoulou, Kalliope; Peters, Annette; Pirastu, Nicola; Polašek, Ozren; Rehnström, Karola; Ripatti, Samuli; Ritchie, Graham R.S.; Rivadeneira, Fernando; Robino, Antonietta; Samani, Nilesh J.; Shin, So-Youn; Sinisalo, Juha; Smit, Johannes H.; Soranzo, Nicole; Stolk, Lisette; Swinkels, Dorine W.; Tanaka, Toshiko; Teumer, Alexander; Tönjes, Anke; Traglia, Michela; Tuomilehto, Jaakko; Valsesia, Armand; van Gilst, Wiek H.; van Meurs, Joyce B.J.; Smith, Albert Vernon; Viikari, Jorma; Vink, Jacqueline M.; Waeber, Gerard; Warrington, Nicole M.; Widen, Elisabeth; Willemsen, Gonneke; Wright, Alan F.; Zanke, Brent W.; Zgaga, Lina; Boehnke, Michael; d'Adamo, Adamo Pio; de Geus, Eco; Demerath, Ellen W.; den Heijer, Martin; Eriksson, Johan G.; Ferrucci, Luigi; Gieger, Christian; Gudnason, Vilmundur; Hayward, Caroline; Hengstenberg, Christian; Hudson, Thomas J.; Järvelin, Marjo-Riitta; Kogevinas, Manolis; Loos, Ruth J.F.; Martin, Nicholas G.; Metspalu, Andres; Pennell, Craig E.; Penninx, Brenda W.; Perola, Markus; Raitakari, Olli; Salomaa, Veikko; Schreiber, Stefan; Schunkert, Heribert; Spector, Tim D.; Stumvoll, Michael; Uitterlinden, André G.; Ulivi, Sheila; van der Harst, Pim; Vollenweider, Peter; Völzke, Henry; Wareham, Nicholas J.; Wichmann, H.-Erich; Wilson, James F.; Rudan, Igor; Xue, Yali; Zeggini, Eleftheria

2012-01-01

The male-to-female sex ratio at birth is constant across world populations with an average of 1.06 (106 male to 100 female live births) for populations of European descent. The sex ratio is considered to be affected by numerous biological and environmental factors and to have a heritable component. The aim of this study was to investigate the presence of common allele modest effects at autosomal and chromosome X variants that could explain the observed sex ratio at birth. We conducted a large-scale genome-wide association scan (GWAS) meta-analysis across 51 studies, comprising overall 114 863 individuals (61 094 women and 53 769 men) of European ancestry and 2 623 828 common (minor allele frequency >0.05) single-nucleotide polymorphisms (SNPs). Allele frequencies were compared between men and women for directly-typed and imputed variants within each study. Forward-time simulations for unlinked, neutral, autosomal, common loci were performed under the demographic model for European populations with a fixed sex ratio and a random mating scheme to assess the probability of detecting significant allele frequency differences. We do not detect any genome-wide significant (P < 5 × 10−8) common SNP differences between men and women in this well-powered meta-analysis. The simulated data provided results entirely consistent with these findings. This large-scale investigation across ∼115 000 individuals shows no detectable contribution from common genetic variants to the observed skew in the sex ratio. The absence of sex-specific differences is useful in guiding genetic association study design, for example when using mixed controls for sex-biased traits. PMID:22843499

Deficient and Null Variants of SERPINA1 Are Proteotoxic in a Caenorhabditis elegans Model of α1-Antitrypsin Deficiency.

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Erin E Cummings

Full Text Available α1-antitrypsin deficiency (ATD predisposes patients to both loss-of-function (emphysema and gain-of-function (liver cirrhosis phenotypes depending on the type of mutation. Although the Z mutation (ATZ is the most prevalent cause of ATD, >120 mutant alleles have been identified. In general, these mutations are classified as deficient (<20% normal plasma levels or null (<1% normal levels alleles. The deficient alleles, like ATZ, misfold in the ER where they accumulate as toxic monomers, oligomers and aggregates. Thus, deficient alleles may predispose to both gain- and loss-of-function phenotypes. Null variants, if translated, typically yield truncated proteins that are efficiently degraded after being transiently retained in the ER. Clinically, null alleles are only associated with the loss-of-function phenotype. We recently developed a C. elegans model of ATD in order to further elucidate the mechanisms of proteotoxicity (gain-of-function phenotype induced by the aggregation-prone deficient allele, ATZ. The goal of this study was to use this C. elegans model to determine whether different types of deficient and null alleles, which differentially affect polymerization and secretion rates, correlated to any extent with proteotoxicity. Animals expressing the deficient alleles, Mmalton, Siiyama and S (ATS, showed overall toxicity comparable to that observed in patients. Interestingly, Siiyama expressing animals had smaller intracellular inclusions than ATZ yet appeared to have a greater negative effect on animal fitness. Surprisingly, the null mutants, although efficiently degraded, showed a relatively mild gain-of-function proteotoxic phenotype. However, since null variant proteins are degraded differently and do not appear to accumulate, their mechanism of proteotoxicity is likely to be different to that of polymerizing, deficient mutants. Taken together, these studies showed that C. elegans is an inexpensive tool to assess the proteotoxicity of

Multiplexed enrichment of rare DNA variants via sequence-selective and temperature-robust amplification

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Wu, Lucia R.; Chen, Sherry X.; Wu, Yalei; Patel, Abhijit A.; Zhang, David Yu

2018-01-01

Rare DNA-sequence variants hold important clinical and biological information, but existing detection techniques are expensive, complex, allele-specific, or don’t allow for significant multiplexing. Here, we report a temperature-robust polymerase-chain-reaction method, which we term blocker displacement amplification (BDA), that selectively amplifies all sequence variants, including single-nucleotide variants (SNVs), within a roughly 20-nucleotide window by 1,000-fold over wild-type sequences. This allows for easy detection and quantitation of hundreds of potential variants originally at ≤0.1% in allele frequency. BDA is compatible with inexpensive thermocycler instrumentation and employs a rationally designed competitive hybridization reaction to achieve comparable enrichment performance across annealing temperatures ranging from 56 °C to 64 °C. To show the sequence generality of BDA, we demonstrate enrichment of 156 SNVs and the reliable detection of single-digit copies. We also show that the BDA detection of rare driver mutations in cell-free DNA samples extracted from the blood plasma of lung-cancer patients is highly consistent with deep sequencing using molecular lineage tags, with a receiver operator characteristic accuracy of 95%. PMID:29805844

Variant allele frequency enrichment analysis in vitro reveals sonic hedgehog pathway to impede sustained temozolomide response in GBM.

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Biswas, Nidhan K; Chandra, Vikas; Sarkar-Roy, Neeta; Das, Tapojyoti; Bhattacharya, Rabindra N; Tripathy, Laxmi N; Basu, Sunandan K; Kumar, Shantanu; Das, Subrata; Chatterjee, Ankita; Mukherjee, Ankur; Basu, Pryiadarshi; Maitra, Arindam; Chattopadhyay, Ansuman; Basu, Analabha; Dhara, Surajit

2015-01-21

Neoplastic cells of Glioblastoma multiforme (GBM) may or may not show sustained response to temozolomide (TMZ) chemotherapy. We hypothesize that TMZ chemotherapy response in GBM is predetermined in its neoplastic clones via a specific set of mutations that alter relevant pathways. We describe exome-wide enrichment of variant allele frequencies (VAFs) in neurospheres displaying contrasting phenotypes of sustained versus reversible TMZ-responses in vitro. Enrichment of VAFs was found on genes ST5, RP6KA1 and PRKDC in cells showing sustained TMZ-effect whereas on genes FREM2, AASDH and STK36, in cells showing reversible TMZ-effect. Ingenuity pathway analysis (IPA) revealed that these genes alter cell-cycle, G2/M-checkpoint-regulation and NHEJ pathways in sustained TMZ-effect cells whereas the lysine-II&V/phenylalanine degradation and sonic hedgehog (Hh) pathways in reversible TMZ-effect cells. Next, we validated the likely involvement of the Hh-pathway in TMZ-response on additional GBM neurospheres as well as on GBM patients, by extracting RNA-sequencing-based gene expression data from the TCGA-GBM database. Finally, we demonstrated TMZ-sensitization of a TMZ non-responder neurosphere in vitro by treating them with the FDA-approved pharmacological Hh-pathway inhibitor vismodegib. Altogether, our results indicate that the Hh-pathway impedes sustained TMZ-response in GBM and could be a potential therapeutic target to enhance TMZ-response in this malignancy.

Consistent association of type 2 diabetes risk variants found in europeans in diverse racial and ethnic groups.

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Kevin M Waters

2010-08-01

Full Text Available It has been recently hypothesized that many of the signals detected in genome-wide association studies (GWAS to T2D and other diseases, despite being observed to common variants, might in fact result from causal mutations that are rare. One prediction of this hypothesis is that the allelic associations should be population-specific, as the causal mutations arose after the migrations that established different populations around the world. We selected 19 common variants found to be reproducibly associated to T2D risk in European populations and studied them in a large multiethnic case-control study (6,142 cases and 7,403 controls among men and women from 5 racial/ethnic groups (European Americans, African Americans, Latinos, Japanese Americans, and Native Hawaiians. In analysis pooled across ethnic groups, the allelic associations were in the same direction as the original report for all 19 variants, and 14 of the 19 were significantly associated with risk. In summing the number of risk alleles for each individual, the per-allele associations were highly statistically significant (P<10(-4 and similar in all populations (odds ratios 1.09-1.12 except in Japanese Americans the estimated effect per allele was larger than in the other populations (1.20; P(het = 3.8×10(-4. We did not observe ethnic differences in the distribution of risk that would explain the increased prevalence of type 2 diabetes in these groups as compared to European Americans. The consistency of allelic associations in diverse racial/ethnic groups is not predicted under the hypothesis of Goldstein regarding "synthetic associations" of rare mutations in T2D.

Cognitive function and apolipoprotein E in very old adults: findings from the Nun Study.

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Riley, K P; Snowdon, D A; Saunders, A M; Roses, A D; Mortimer, J A; Nanayakkara, N

2000-03-01

The epsilon4 allele of apolipoprotein E (APOE) has been associated with Alzheimer' s disease and with milder forms of cognitive impairment. We investigated the possibility that the absence of the epsilon4 allele may predict the maintenance of high cognitive function among very old individuals. Our data are from the Nun Study, a longitudinal study of aging and Alzheimer's disease in 678 Catholic sisters. All sisters participate in annual functional exams that include the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) battery of cognitive tests. High cognitive function was defined as intact scores on five of the CERAD tests. A total of 241 participants aged 75 to 98 met this criterion at the first exam. Findings showed that 62% of the 241 participants maintained intact scores on the five CERAD tests throughout their participation in the study. Life table analyses indicated that those without the APOE epsilon4 allele spent more time with intact cognitive function than those with the epsilon4 allele (p = .007). Cox regression analyses indicated that those without the epsilon4 allele had half the risk of losing their intact status during the study when compared with those with the epsilon4 allele (p < .01). Our findings suggest that the APOE epsilon4 allele may be included among the variables that predict high cognitive function in cognitively intact, very old adults. Although the presence or absence of the epsilon4 allele is known to be related to the risk of dementia, it also appears to be related to maintaining high levels of cognitive function in old age.

Impact of BDNF Val66Met and 5-HTTLPR polymorphism variants on neural substrates related to sadness and executive function.

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Wang, L; Ashley-Koch, A; Steffens, D C; Krishnan, K R R; Taylor, W D

2012-04-01

The brain-derived neurotrophic factor (BDNF) Val(66) Met allelic variation is linked to both the occurrence of mood disorders and antidepressant response. These findings are not universally observed, and the mechanism by which this variation results in increased risk for mood disorders is unclear. One possible explanation is an epistatic relationship with other neurotransmitter genes associated with depression risk, such as the serotonin-transporter-linked promotor region (5-HTTLPR). Further, it is unclear how the coexistence of the BDNF Met and 5-HTTLPR S variants affects the function of the affective and cognitive control systems. To address this question, we conducted a functional magnetic resonance imaging (fMRI) study in 38 older adults (20 healthy and 18 remitted from major depressive disorder). Subjects performed an emotional oddball task during the fMRI scan and provided blood samples for genotyping. Our analyses examined the relationship between genotypes and brain activation to sad distractors and attentional targets. We found that 5-HTTLPR S allele carriers exhibited stronger activation in the amygdala in response to sad distractors, whereas BDNF Met carriers exhibited increased activation to sad stimuli but decreased activation to attentional targets in the dorsolateral prefrontal and dorsomedial prefrontal cortices. In addition, subjects with both the S allele and Met allele genes exhibited increased activation to sad stimuli in the subgenual cingulate and posterior cingulate. Our results indicate that the Met allele alone or in combination with 5-HTTLPR S allele may increase reactivity to sad stimuli, which might represent a neural mechanism underlying increased depression vulnerability. © 2012 The Authors. Genes, Brain and Behavior © 2012 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

Allele-specific cytokine responses at the HLA-C locus, implications for psoriasis

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Hundhausen, Christian; Bertoni, Anna; Mak, Rose K; Botti, Elisabetta; Di Meglio, Paola; Clop, Alex; Laggner, Ute; Chimenti, Sergio; Hayday, Adrian C; Barker, Jonathan N; Trembath, Richard C; Capon, Francesca; Nestle, Frank O

2011-01-01

Psoriasis is an inflammatory skin disorder that is inherited as a complex trait. Genetic studies have repeatedly highlighted HLA-C as the major determinant for psoriasis susceptibility, with the Cw*0602 allele conferring significant disease risk in a wide-range of populations. Despite the potential importance of HLA-C variation in psoriasis, either via an effect on peptide presentation or immuno-inhibitory activity, allele-specific expression patterns have not been investigated. Here, we used reporter assays to characterize two regulatory variants, which virtually abolished the response to TNF-α (rs2524094) and IFN-γ (rs10657191) in HLA-Cw*0602 and a cluster of related alleles. We validated these findings through the analysis of HLA-Cw*0602 expression in primary keratinocytes treated with TNF-α and IFN-γ. Finally, we showed that HLA-Cw*0602 transcripts are not increased in psoriatic skin lesions, despite highly elevated TNF-α levels. Thus, our findings demonstrate the presence of allele-specific differences in HLA-C expression and indicate that HLA-Cw*0602 is unresponsive to up-regulation by key pro-inflammatory cytokines in psoriasis. These data pave the way for functional studies into the pathogenic role of the major psoriasis susceptibility allele. PMID:22113476

Allele-specific cytokine responses at the HLA-C locus: implications for psoriasis.

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Hundhausen, Christian; Bertoni, Anna; Mak, Rose K; Botti, Elisabetta; Di Meglio, Paola; Clop, Alex; Laggner, Ute; Chimenti, Sergio; Hayday, Adrian C; Barker, Jonathan N; Trembath, Richard C; Capon, Francesca; Nestle, Frank O

2012-03-01

Psoriasis is an inflammatory skin disorder that is inherited as a complex trait. Genetic studies have repeatedly highlighted HLA-C as the major determinant for psoriasis susceptibility, with the Cw*0602 allele conferring significant disease risk in a wide range of populations. Despite the potential importance of HLA-C variation in psoriasis, either via an effect on peptide presentation or immuno-inhibitory activity, allele-specific expression patterns have not been investigated. Here, we used reporter assays to characterize two regulatory variants, which virtually abolished the response to tumor necrosis factor (TNF)-α (rs2524094) and IFN-γ (rs10657191) in HLA-Cw*0602 and a cluster of related alleles. We validated these findings through the analysis of HLA-Cw*0602 expression in primary keratinocytes treated with TNF-α and IFN-γ. Finally, we showed that HLA-Cw*0602 transcripts are not increased in psoriatic skin lesions, despite highly elevated TNF-α levels. Thus, our findings demonstrate the presence of allele-specific differences in HLA-C expression and indicate that HLA-Cw*0602 is unresponsive to upregulation by key proinflammatory cytokines in psoriasis. These data pave the way for functional studies into the pathogenic role of the major psoriasis susceptibility allele.

Prevalence of melanocortin receptor 4 (MC4R) V103I gene variant and its association with obesity among the Kampar Health Clinic cohort, Perak, Malaysia.

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Chua, H N; Fan, S H; Say, Y H

2012-04-01

This study investigated the prevalence of the Melanocortin receptor 4 (MC4R) V1031 gene variant and its association with obesity among a cohort of 254 patients (101 males; 118 obese) attending the Kampar Health Clinic. Genotyping revealed the mutated I allele frequency of 0.02, no homozygous mutated (II), and similar distribution of V and I alleles across BMI groups, genders and ethnic groups. No significant difference was found for the means of anthropometric measurements between alleles. Prevalence of this gene variant among the Malaysian cohort was similar with previous populations (2-4% of mutated allele carrier), but was not associated with obesity.

Population differentiation in allele frequencies of obesity-associated SNPs.

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Mao, Linyong; Fang, Yayin; Campbell, Michael; Southerland, William M

2017-11-10

Obesity is emerging as a global health problem, with more than one-third of the world's adult population being overweight or obese. In this study, we investigated worldwide population differentiation in allele frequencies of obesity-associated SNPs (single nucleotide polymorphisms). We collected a total of 225 obesity-associated SNPs from a public database. Their population-level allele frequencies were derived based on the genotype data from 1000 Genomes Project (phase 3). We used hypergeometric model to assess whether the effect allele at a given SNP is significantly enriched or depleted in each of the 26 populations surveyed in the 1000 Genomes Project with respect to the overall pooled population. Our results indicate that 195 out of 225 SNPs (86.7%) possess effect alleles significantly enriched or depleted in at least one of the 26 populations. Populations within the same continental group exhibit similar allele enrichment/depletion patterns whereas inter-continental populations show distinct patterns. Among the 225 SNPs, 15 SNPs cluster in the first intron region of the FTO gene, which is a major gene associated with body-mass index (BMI) and fat mass. African populations exhibit much smaller blocks of LD (linkage disequilibrium) among these15 SNPs while European and Asian populations have larger blocks. To estimate the cumulative effect of all variants associated with obesity, we developed the personal composite genetic risk score for obesity. Our results indicate that the East Asian populations have the lowest averages of the composite risk scores, whereas three European populations have the highest averages. In addition, the population-level average of composite genetic risk scores is significantly correlated (R 2 = 0.35, P = 0.0060) with obesity prevalence. We have detected substantial population differentiation in allele frequencies of obesity-associated SNPs. The results will help elucidate the genetic basis which may contribute to population

A common mutation associated with the Duarte galactosemia allele

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Elsas, L.J.; Dembure, P.P.; Langley, S.; Paulk, E.M.; Hjelm, L.N.; Fridovich-Keil, J. (Emory Univ. School of Medicine, Atlanta, GA (United States))

1994-06-01

The human cDNA and gene for galactose-1-phosphate uridyl transferase (GALT) have been cloned and sequenced. A prevalant mutation (Q188R) is known to cause classic galactosemia (G/G). G/G galactosemia has an incidence of 1/38,886 in 1,396,766 Georgia live-born infants, but a more common variant of galactosemia, Duarte, has an unknown incidence. The proposed Duarte biochemical phenotypes of GALT are as follows: D/N, D/D, and D/G, which have [approximately]75%, 50%, and 25% of normal GALT activity, respectively. In addition, the D allele has isoforms of its enzyme that have more acidic pI than normal. Here the authors systematically determine (a) the prevalence of an A-to-G transition at base pair 2744 of exon 10 in the GALT gene, a transition that produces a codon change converting asparagine to aspartic acid at position 314 (N314D), and (b) the association of this mutation with the Duarte biochemical phenotype. The 2744G nucleotide change adds an AvaII (SinI) cut site, which was identified in PCR-amplified DNA. In 111 biochemically unphenotyped controls with no history of galactosemia, 13 N314D alleles were identified (prevalence 5.9%). In a prospective study, 40 D alleles were biochemically phenotyped, and 40 N314D alleles were found. By contrast, in 36 individuals known not to have the Duarte biochemical phenotype, no N314D alleles were found. The authors conclude that the N314D mutation is a common allele that probably causes the Duarte GALT biochemical phenotype and occurs in a predominantly Caucasian, nongalactosemic population, with a prevalence of 5.9%. 36 refs., 3 figs., 2 tabs.

Expression and loss of alleles in cultured mouse embryonic fibroblasts and stem cells carrying allelic fluorescent protein genes

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Stringer Saundra L

2006-10-01

Full Text Available Abstract Background Loss of heterozygosity (LOH contributes to many cancers, but the rate at which these events occur in normal cells of the body is not clear. LOH would be detectable in diverse cell types in the body if this event were to confer an obvious cellular phenotype. Mice that carry two different fluorescent protein genes as alleles of a locus would seem to be a useful tool for addressing this issue because LOH would change a cell's phenotype from dichromatic to monochromatic. In addition, LOH caused by mitotic crossing over might be discernable in tissues because this event produces a pair of neighboring monochromatic cells that are different colors. Results As a step in assessing the utility of this approach, we derived primary embryonic fibroblast populations and embryonic stem cell lines from mice that carried two different fluorescent protein genes as alleles at the chromosome 6 locus, ROSA26. Fluorescence activated cell sorting (FACS showed that the vast majority of cells in each line expressed the two marker proteins at similar levels, and that populations exhibited expression noise similar to that seen in bacteria and yeast. Cells with a monochromatic phenotype were present at frequencies on the order of 10-4 and appeared to be produced at a rate of approximately 10-5 variant cells per mitosis. 45 of 45 stably monochromatic ES cell clones exhibited loss of the expected allele at the ROSA26 locus. More than half of these clones retained heterozygosity at a locus between ROSA26 and the centromere. Other clones exhibited LOH near the centromere, but were disomic for chromosome 6. Conclusion Allelic fluorescent markers allowed LOH at the ROSA26 locus to be detected by FACS. LOH at this locus was usually not accompanied by LOH near the centromere, suggesting that mitotic recombination was the major cause of ROSA26 LOH. Dichromatic mouse embryonic cells provide a novel system for studying genetic/karyotypic stability and factors

Convergent and divergent effects of apolipoprotein E ε4 and ε2 alleles on amygdala functional networks in nondemented older adults.

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Gong, Liang; Shu, Hao; He, Cancan; Ye, Qing; Bai, Feng; Xie, Chunming; Zhang, Zhijun

2017-06-01

Traditionally, in the context of Alzheimer's disease, the apolipoprotein E ε2 (APOEε2) allele is a protective factor and the APOEε4 allele is a destructive factor. However, this inverse relationship has recently been challenged, and the neural mechanisms underlying the effects of APOE genotype on Alzheimer's disease remain unclear. A resting-state functional magnetic resonance imaging study was conducted to investigate the effects of APOE genotype and age on amygdala functional connectivity (AFC) networks in 84 patients with amnestic mild cognitive impairment and 124 cognitively normal order adults. The results indicated that the APOEε2 and APOEε4 alleles produced convergent effects in the right AFC network but divergent effects in the left AFC network. As age increased, APOEε2 carriers showed stable AFC, whereas APOEε4 carriers exhibited decreased AFC in all participants. Furthermore, mediation analysis revealed that connectivity strength regulates the effects of APOE genotype and age on cognitive function in amnestic mild cognitive impairment patients. Our findings suggest that the APOEε2 and APOEε4 alleles produce both convergent and divergent topological effects on brain function. Copyright © 2017 Elsevier Inc. All rights reserved.

Protein-altering variants associated with body mass index implicate pathways that control energy intake and expenditure in obesity

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Turcot, Valérie; Lu, Yingchang; Highland, Heather M; Schurmann, Claudia; Justice, Anne E; Fine, Rebecca S; Bradfield, Jonathan P; Esko, Tõnu; Giri, Ayush; Graff, Mariaelisa; Guo, Xiuqing; Hendricks, Audrey E; Karaderi, Tugce; Lempradl, Adelheid; Locke, Adam E

2018-01-01

Genome-wide association studies (GWAS) have identified >250 loci for body mass index (BMI), implicating pathways related to neuronal biology. Most GWAS loci represent clusters of common, noncoding variants from which pinpointing causal genes remains challenging. Here we combined data from 718,734 individuals to discover rare and low-frequency (minor allele frequency (MAF) < 5%) coding variants associated with BMI. We identified 14 coding variants in 13 genes, of which 8 variants were in...

al mena: a comprehensive resource of human genetic variants integrating genomes and exomes from Arab, Middle Eastern and North African populations.

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Koshy, Remya; Ranawat, Anop; Scaria, Vinod

2017-10-01

Middle East and North Africa (MENA) encompass very unique populations, with a rich history and encompasses characteristic ethnic, linguistic and genetic diversity. The genetic diversity of MENA region has been largely unknown. The recent availability of whole-exome and whole-genome sequences from the region has made it possible to collect population-specific allele frequencies. The integration of data sets from this region would provide insights into the landscape of genetic variants in this region. We integrated genetic variants from multiple data sets systematically, available from this region to create a compendium of over 26 million genetic variations. The variants were systematically annotated and their allele frequencies in the data sets were computed and available as a web interface which enables quick query. As a proof of principle for application of the compendium for genetic epidemiology, we analyzed the allele frequencies for variants in transglutaminase 1 (TGM1) gene, associated with autosomal recessive lamellar ichthyosis. Our analysis revealed that the carrier frequency of selected variants differed widely with significant interethnic differences. To the best of our knowledge, al mena is the first and most comprehensive repertoire of genetic variations from the Arab, Middle Eastern and North African region. We hope al mena would accelerate Precision Medicine in the region.

The cognitive profile of behavioural variant FTD and its similarities with ALS: a systematic review and meta-analysis.

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Beeldman, Emma; Raaphorst, Joost; Klein Twennaar, Michelle; Govaarts, Rosanne; Pijnenburg, Yolande A L; de Haan, Rob J; de Visser, Marianne; Schmand, Ben A

2018-02-09

Approximately 30% of patients with amyotrophic lateral sclerosis (ALS) have cognitive impairment and 8%-14% fulfil the criteria for behavioural variant frontotemporal dementia (bv-FTD). The cognitive profiles of ALS and bv-FTD have been reported to be comparable, but this has never been systematically investigated. We aimed to determine the cognitive profile of bv-FTD and examine its similarities with that of ALS, to provide evidence for the existence of a cognitive disease continuum encompassing bv-FTD and ALS. We therefore systematically reviewed neuropsychological studies on bv-FTD patients and healthy volunteers. Neuropsychological tests were divided in 10 cognitive domains and effect sizes were calculated for all domains and compared with the cognitive profile of ALS by means of a visual comparison and a Pearson's r correlation coefficient. We included 120 studies, totalling 2425 bv-FTD patients and 2798 healthy controls. All cognitive domains showed substantial effect sizes, indicating cognitive impairment in bv-FTD patients compared to healthy controls. The cognitive domains with the largest effect sizes were social cognition, verbal memory and fluency (1.77-1.53). The cognitive profiles of bv-FTD and ALS (10 cognitive domains, 1287 patients) showed similarities on visual comparison and a moderate correlation 0.58 (p=0.13). When social cognition, verbal memory, fluency, executive functions, language and visuoperception were considered, i.e. the cognitive profile of ALS, Pearson's r was 0.73 (p=0.09), which raised to 0.92 (p=0.03), when language was excluded in this systematic analysis of patients with a non-language subtype of FTD. The cognitive profile of bv-FTD consists of deficits in social cognition, verbal memory, fluency and executive functions and shows similarities with the cognitive profile of ALS. These findings support a cognitive continuum encompassing ALS and bv-FTD. © Article author(s) (or their employer(s) unless otherwise stated in the text

Functional Analysis of Cancer-Associated DNA Polymerase ε Variants in Saccharomyces cerevisiae

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Stephanie R. Barbari

2018-03-01

Full Text Available DNA replication fidelity relies on base selectivity of the replicative DNA polymerases, exonucleolytic proofreading, and postreplicative DNA mismatch repair (MMR. Ultramutated human cancers without MMR defects carry alterations in the exonuclease domain of DNA polymerase ε (Polε. They have been hypothesized to result from defective proofreading. However, modeling of the most common variant, Polε-P286R, in yeast produced an unexpectedly strong mutator effect that exceeded the effect of proofreading deficiency by two orders of magnitude and indicated the involvement of other infidelity factors. The in vivo consequences of many additional Polε mutations reported in cancers remain poorly understood. Here, we genetically characterized 13 cancer-associated Polε variants in the yeast system. Only variants directly altering the DNA binding cleft in the exonuclease domain elevated the mutation rate. Among these, frequently recurring variants were stronger mutators than rare variants, in agreement with the idea that mutator phenotype has a causative role in tumorigenesis. In nearly all cases, the mutator effects exceeded those of an exonuclease-null allele, suggesting that mechanisms distinct from loss of proofreading may drive the genome instability in most ultramutated tumors. All mutator alleles were semidominant, supporting the view that heterozygosity for the polymerase mutations is sufficient for tumor development. In contrast to the DNA binding cleft alterations, peripherally located variants, including a highly recurrent V411L, did not significantly elevate mutagenesis. Finally, the analysis of Polε variants found in MMR-deficient tumors suggested that the majority cause no mutator phenotype alone but some can synergize with MMR deficiency to increase the mutation rate.

A genetic variant within STS previously associated with inattention in boys with attention deficit hyperactivity disorder is associated with enhanced cognition in healthy adult males.

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Humby, Trevor; Fisher, Amelia; Allen, Christopher; Reynolds, Meghann; Hartman, Annette; Giegling, Ina; Rujescu, Dan; Davies, William

2017-03-01

The enzyme steroid sulfatase (STS) converts sulfated steroids to their non-sulfated forms. Deficiency for this enzyme is associated with inattention but preserved response control. The polymorphism rs17268988 within the X-linked STS gene is associated with inattentive, but not other, symptoms in boys with attention deficit hyperactivity disorder (ADHD). We initially tested whether rs17268988 genotype was associated with attention, response control, and underlying aspects of cognition, using questionnaires and neuropsychological tasks, in two independent cohorts of healthy adult males. In an additional analysis based upon existing data, the performance of mice with genetic or pharmacological manipulations of the STS axis under attentionally demanding conditions was investigated. G-allele carriers at rs17268988 exhibited reduced reaction time, enhanced attention, and reduced reaction time variability relative to C-allele carriers. Mice with genetic or pharmacological manipulations of the STS axis were shown to have perturbed reaction time variability. Our findings provide additional support for an association between rs17268988 genotype and attention, which may be partially mediated by reaction time variability; they also indicate that, in contrast to the situation in boys with ADHD, in healthy men, the G-allele at rs17268988 is associated with enhanced cognition. As reaction time variability is a predictor of well-being, rs17268988 genotype may represent a biomarker for long-term health.

Identification of low-frequency variants associated with gout and serum uric acid levels

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Sulem, Patrick; Gudbjartsson, Daniel F; Walters, G Bragi

2011-01-01

,506 individuals for whom serum uric acid measurements were available. We identified a low-frequency missense variant (c.1580C>G) in ALDH16A1 associated with gout (OR = 3.12, P = 1.5 × 10(-16), at-risk allele frequency = 0.019) and serum uric acid levels (effect = 0.36 s.d., P = 4.5 × 10(-21)). We confirmed.......48 s.d., P = 4.5 × 10(-16)). This variant is close to a common variant previously associated with serum uric acid levels. This work illustrates how whole-genome sequencing data allow the detection of associations between low-frequency variants and complex traits....

HFE gene variants and iron-induced oxygen radical generation in idiopathic pulmonary fibrosis.

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Sangiuolo, Federica; Puxeddu, Ermanno; Pezzuto, Gabriella; Cavalli, Francesco; Longo, Giuliana; Comandini, Alessia; Di Pierro, Donato; Pallante, Marco; Sergiacomi, Gianluigi; Simonetti, Giovanni; Zompatori, Maurizio; Orlandi, Augusto; Magrini, Andrea; Amicosante, Massimo; Mariani, Francesca; Losi, Monica; Fraboni, Daniela; Bisetti, Alberto; Saltini, Cesare

2015-02-01

In idiopathic pulmonary fibrosis (IPF), lung accumulation of excessive extracellular iron and macrophage haemosiderin may suggest disordered iron homeostasis leading to recurring microscopic injury and fibrosing damage. The current study population comprised 89 consistent IPF patients and 107 controls. 54 patients and 11 controls underwent bronchoalveolar lavage (BAL). Haemosiderin was assessed by Perls' stain, BAL fluid malondialdehyde (MDA) by high-performance liquid chromatography, BAL cell iron-dependent oxygen radical generation by fluorimetry and the frequency of hereditary haemochromatosis HFE gene variants by reverse dot blot hybridisation. Macrophage haemosiderin, BAL fluid MDA and BAL cell unstimulated iron-dependent oxygen radical generation were all significantly increased above controls (pHFE allelic variants was markedly higher in IPF compared with controls (40.4% versus 22.4%, OR 2.35, p=0.008) and was associated with higher iron-dependent oxygen radical generation (HFE variant 107.4±56.0, HFE wild type (wt) 59.4±36.4 and controls 16.7±11.8 fluorescence units per 10(5) BAL cells; p=0.028 HFE variant versus HFE wt, p=0.006 HFE wt versus controls). The data suggest iron dysregulation associated with HFE allelic variants may play an important role in increasing susceptibility to environmental exposures, leading to recurring injury and fibrosis in IPF. Copyright ©ERS 2015.

Genetic variants of SLC11A1 are associated with both autoimmune and infectious diseases: systematic review and meta-analysis.

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Archer, N S; Nassif, N T; O'Brien, B A

2015-06-01

A systematic review and meta-analyses were undertaken to investigate the association of SLC11A1 genetic variants with disease occurrence. Literature searching indentified 109 publications to include in the meta-analyses assessing the association of 11 SLC11A1 variants with autoimmune and infectious disease. The (GT)n promoter alleles 2 and 3 (rs534448891), which alter SLC11A1 expression, were significantly associated with tuberculosis (OR=1.47 (1.30-1.66), OR=0.76 (0.65-0.89), respectively) and infectious disease (OR=1.25 (1.10-1.42), OR=0.83 (0.74-0.93), respectively). However, although no association was observed with autoimmune disease, a modest significant association was observed with type 1 diabetes (allele 2 OR=0.94 (0.89-0.98)). On the basis of a stronger association of (GT)n allele 2 with tuberculosis, compared with the protective effect of allele 3, we hypothesise that allele 2 is likely the disease-causing variant influencing disease susceptibility. Significant associations were observed between the 469+14G/C polymorphism (rs3731865) and autoimmune disease (OR=1.30 (1.04-1.64)) and rheumatoid arthritis (OR=1.60 (1.20-2.13)) and between the -237C/T polymorphism (rs7573065) and inflammatory bowel disease (OR=0.60 (0.43-0.84)). Further, significant associations were identified between the 469+14G/C, 1730G/A and 1729+55del4 polymorphisms (rs3731865, rs17235409 and rs17235416, respectively) and both infectious disease per se and tuberculosis. These findings show a clear association between variants in the SLC11A1 locus and autoimmune and infectious disease susceptibility.

Rs895819 in MIR27A improves the predictive value of DPYD variants to identify patients at risk of severe fluoropyrimidine-associated toxicity.

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Meulendijks, Didier; Henricks, Linda M; Amstutz, Ursula; Froehlich, Tanja K; Largiadèr, Carlo R; Beijnen, Jos H; de Boer, Anthonius; Deenen, Maarten J; Cats, Annemieke; Schellens, Jan H M

2016-06-01

The objective of this study was to determine whether genotyping of MIR27A polymorphisms rs895819A>G and rs11671784C>T can be used to improve the predictive value of DPYD variants to identify patients at risk of severe fluoropyrimidine-associated toxicity (FP-toxicity). Patients treated previously in a prospective study with fluoropyrimidine-based chemotherapy were genotyped for rs895819 and rs11671784, and DPYD c.2846A>T, c.1679T>G, c.1129-5923C>G and c.1601G>A. The predictive value of MIR27A variants for early-onset grade ≥3 FP-toxicity, alone or in combination with DPYD variants, was tested in multivariable logistic regression models. Random-effects meta-analysis was performed, including previously published data. A total of 1,592 patients were included. Allele frequencies of rs895819 and rs11671784 were 0.331 and 0.020, respectively. In DPYD wild-type patients, MIR27A variants did not affect risk of FP-toxicity (OR 1.3 for ≥1 variant MIR27A allele vs. none, 95% CI: 0.87-1.82, p = 0.228). In contrast, in patients carrying DPYD variants, the presence of ≥1 rs895819 variant allele was associated with increased risk of FP-toxicity (OR 4.9, 95% CI: 1.24-19.7, p = 0.023). Rs11671784 was not associated with FP-toxicity (OR 2.9, 95% CI: 0.47-18.0, p = 0.253). Patients carrying a DPYD variant and rs895819 were at increased risk of FP-toxicity compared to patients wild type for rs895819 and DPYD (OR 2.4, 95% CI: 1.27-4.37, p = 0.007), while patients with a DPYD variant but without a MIR27A variant were not (OR 0.3 95% CI: 0.06-1.17, p = 0.081). In meta-analysis, rs895819 remained significantly associated with FP-toxicity in DPYD variant allele carriers, OR 5.4 (95% CI: 1.83-15.7, p = 0.002). This study demonstrates the clinical validity of combined MIR27A/DPYD screening to identify patients at risk of severe FP-toxicity. © 2016 UICC.

Common type 2 diabetes risk gene variants associate with gestational diabetes

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Lauenborg, Jeannet; Grarup, Niels; Damm, Peter

2009-01-01

Objective: We aimed to examine the association between gestational diabetes (GDM) and eleven recently identified type 2 diabetes susceptibility loci. Research Design and Methods: Type 2 diabetes risk variants in TCF7L2, CDKAL1, SLC30A8, HHEX/IDE, CDKN2A/2B, IGF2BP2, FTO, TCF2, PPARG, KCNJ11 and WFS......1 loci were genotyped in a cohort of women with a history of GDM (n=283) and in glucose tolerant women of the population-based Inter99 cohort (n=2,446). Results: All the risk alleles in the 11 examined type 2 diabetes risk variants showed an odds ratio greater than 1 for the GDM group compared...... previously proven type 2 diabetes risk alleles equals the findings from association studies on type 2 diabetes. This supports the hypothesis that GDM and type 2 diabetes are two of the same entity....

BACH1 Ser919Pro variant and breast cancer risk

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Eerola Hannaleena

2006-01-01

Full Text Available Abstract Background BACH1 (BRCA1-associated C-terminal helicase 1; also known as BRCA1-interacting protein 1, BRIP1 is a helicase protein that interacts in vivo with BRCA1, the protein product of one of the major genes for hereditary predisposition to breast cancer. Previously, two BACH1 germ line missense mutations have been identified in early-onset breast cancer patients with and without family history of breast and ovarian cancer. In this study, we aimed to evaluate whether there are BACH1 genetic variants that contribute to breast cancer risk in Finland. Methods The BACH1 gene was screened for germ line alterations among probands from 43 Finnish BRCA1/2 negative breast cancer families. Recently, one of the observed common variants, Ser-allele of the Ser919Pro polymorphism, was suggested to associate with an increased breast cancer risk, and was here evaluated in an independent, large series of 888 unselected breast cancer patients and in 736 healthy controls. Results Six BACH1 germ line alterations were observed in the mutation analysis, but none of these were found to associate with the cancer phenotype. The Val193Ile variant that was seen in only one family was further screened in an independent series of 346 familial breast cancer cases and 183 healthy controls, but no additional carriers were observed. Individuals with the BACH1 Ser919-allele were not found to have an increased breast cancer risk when the Pro/Ser heterozygotes (OR 0.90; 95% CI 0.70–1.16; p = 0.427 or Ser/Ser homozygotes (OR 1.02; 95% CI 0.76–1.35; p = 0.91 were compared to Pro/Pro homozygotes, and there was no association of the variant with any breast tumor characteristics, age at cancer diagnosis, family history of cancer, or survival. Conclusion Our results suggest that the BACH1 Ser919 is not a breast cancer predisposition allele in the Finnish study population. Together with previous studies, our results also indicate that although some rare germ line variants

BACH1 Ser919Pro variant and breast cancer risk

International Nuclear Information System (INIS)

Vahteristo, Pia; Yliannala, Kristiina; Tamminen, Anitta; Eerola, Hannaleena; Blomqvist, Carl; Nevanlinna, Heli

2006-01-01

BACH1 (BRCA1-associated C-terminal helicase 1; also known as BRCA1-interacting protein 1, BRIP1) is a helicase protein that interacts in vivo with BRCA1, the protein product of one of the major genes for hereditary predisposition to breast cancer. Previously, two BACH1 germ line missense mutations have been identified in early-onset breast cancer patients with and without family history of breast and ovarian cancer. In this study, we aimed to evaluate whether there are BACH1 genetic variants that contribute to breast cancer risk in Finland. The BACH1 gene was screened for germ line alterations among probands from 43 Finnish BRCA1/2 negative breast cancer families. Recently, one of the observed common variants, Ser-allele of the Ser919Pro polymorphism, was suggested to associate with an increased breast cancer risk, and was here evaluated in an independent, large series of 888 unselected breast cancer patients and in 736 healthy controls. Six BACH1 germ line alterations were observed in the mutation analysis, but none of these were found to associate with the cancer phenotype. The Val193Ile variant that was seen in only one family was further screened in an independent series of 346 familial breast cancer cases and 183 healthy controls, but no additional carriers were observed. Individuals with the BACH1 Ser919-allele were not found to have an increased breast cancer risk when the Pro/Ser heterozygotes (OR 0.90; 95% CI 0.70–1.16; p = 0.427) or Ser/Ser homozygotes (OR 1.02; 95% CI 0.76–1.35; p = 0.91) were compared to Pro/Pro homozygotes, and there was no association of the variant with any breast tumor characteristics, age at cancer diagnosis, family history of cancer, or survival. Our results suggest that the BACH1 Ser919 is not a breast cancer predisposition allele in the Finnish study population. Together with previous studies, our results also indicate that although some rare germ line variants in BACH1 may contribute to breast cancer development, the

Maternal variant in the upstream of FOXP3 gene on the X chromosome is associated with recurrent infertility in Japanese Black cattle.

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Arishima, Taichi; Sasaki, Shinji; Isobe, Tomohiro; Ikebata, Yoshihisa; Shimbara, Shinichi; Ikeda, Shogo; Kawashima, Keisuke; Suzuki, Yutaka; Watanabe, Manabu; Sugano, Sumio; Mizoshita, Kazunori; Sugimoto, Yoshikazu

2017-12-06

Repeat breeding, which is defined as cattle failure to conceive after three or more inseminations in the absence of clinical abnormalities, is a substantial problem in cattle breeding. To identify maternal genetic variants of repeat breeding in Japanese Black cattle, we selected 29 repeat-breeding heifers that failed to conceive following embryo transfer (ET) and conducted a genome-wide association study (GWAS) using the traits. We found that a single-nucleotide polymorphism (SNP; g.92,377,635A > G) in the upstream region of the FOXP3 gene on the X chromosome was highly associated with repeat breeding and failure to conceive following ET (P = 1.51 × 10 -14 ). FOXP3 is a master gene for differentiation of regulatory T (T reg ) cells that function in pregnancy maintenance. Reporter assay results revealed that the activity of the FOXP3 promoter was lower in reporter constructs with the risk-allele than in those with the non-risk-allele by approximately 0.68 fold. These findings suggest that the variant in the upstream region of FOXP3 with the risk-allele decreased FOXP3 transcription, which in turn, could reduce the number of maternal T reg cells and lead to infertility. The frequency of the risk-allele in repeat-breeding heifers is more than that in cows, suggesting that the risk-allele could be associated with infertility in repeat-breeding heifers. This GWAS identified a maternal variant in the upstream region of FOXP3 that was associated with infertility in repeat-breeding Japanese Black cattle that failed to conceive using ET. The variant affected the level of FOXP3 mRNA expression. Thus, the results suggest that the risk-allele could serve as a useful marker to reduce and eliminate animals with inferior fertility in Japanese Black cattle.

Role of IL-17 Variants in Preeclampsia in Chinese Han Women.

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Haiyan Wang

Full Text Available Previous studies have suggested an important role for IL-17, mainly secreted by Th17 cells, in the development of systemic inflammation in preeclampsia (PE. This study therefore investigated the association between genetic variants in IL-17A, IL-17F, and IL-17RA and susceptibility to PE in Chinese Han women. We recruited 1,031 PE patients and 1,298 controls of later pregnant women, and used TaqMan allelic discrimination real-time PCR to genotype the polymorphisms of IL17A rs2275913, IL-17F rs763780, and IL-17RA rs4819554. No significant differences in genotypic or allelic frequencies were found at all three polymorphic sites between PE patients and controls (rs2275913: genotype χ2 = 0.218, p = 0.897 and allele χ2 = 0.157, p = 0.692, OR = 1.024, 95%CI 0.911-1.152; rs763780: genotype χ2 = 1.948, p = 0.377 and allele χ2 = 1.242, p = 0.265, OR = 0.897, 95%CI 0.741-1.086; rs4819554: genotype χ2 = 0.633, p = 0.729 and allele χ2 = 0.115, p = 0.735, OR = 1.020, 95%CI 0.908-1.146. There were also no significant differences in genetic distributions between mild/severe PE or early/late-onset PE and control subgroups. Our data indicate that the genetic variants of rs2275913 in IL-17A, rs763780 in IL-17F, and rs4819554 in IL-17RA may not play a role in the pathogenesis of PE in Chinese Han women. However, these findings should be confirmed in other ethnic populations.

Most of rare missense alleles in humans are deleterious:implications for evolution of complex disease and associationstudies

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Kryukov, Gregory V.; Pennacchio, Len A.; Sunyaev, Shamil R.

2006-10-24

The accumulation of mildly deleterious missense mutations inindividual human genomes has been proposed to be a genetic basis forcomplex diseases. The plausibility of this hypothesis depends onquantitative estimates of the prevalence of mildly deleterious de novomutations and polymorphic variants in humans and on the intensity ofselective pressure against them. We combined analysis of mutationscausing human Mendelian diseases, human-chimpanzee divergence andsystematic data on human SNPs and found that about 20 percent of newmissense mutations in humans result in a loss of function, while about 27percent are effectively neutral. Thus, more than half of new missensemutations have mildly deleterious effects. These mutations give rise tomany low frequency deleterious allelic variants in the human populationas evident from a new dataset of 37 genes sequenced in over 1,500individual human chromosomes. Surprisingly, up to 70 percent of lowfrequency missense alleles are mildly deleterious and associated with aheterozygous fitness loss in the range 0.001-0.003. Thus, the low allelefrequency of an amino acid variant can by itself serve as a predictor ofits functional significance. Several recent studies have reported asignificant excess of rare missense variants in disease populationscompared to controls in candidate genes or pathways. These studies wouldbe unlikely to work if most rare variants were neutral or if rarevariants were not a significant contributor to the genetic component ofphenotypic inheritance. Our results provide a justification for thesetypes of candidate gene (pathway) association studies and imply thatmutation-selection balance may be a feasible mechanism for evolution ofsome common diseases.

Interaction between the Gly460Trp alpha-adducin gene variant and diuretics on the risk of myocardial infarction

NARCIS (Netherlands)

van Wieren-de Wijer, Diane B M A; Maitland-van der Zee, Anke-Hilse; de Boer, Anthonius; Kroon, Abraham A; de Leeuw, Peter W; Schiffers, Paul; Janssen, Rob G J H; Psaty, Bruce M; van Duijn, Cornelia M; Stricker, Bruno H Ch; Klungel, Olaf H

INTRODUCTION: The Gly460Trp variant of the alpha-adducin gene has been associated with the salt-sensitive and diuretic responsive form of hypertension. OBJECTIVE: The aim of the study was to determine whether the alpha-adducin 460Trp variant allele modifies the risk-lowering effect of diuretics on

The NRG1 exon 11 missense variant is not associated with autism in the Central Valley of Costa Rica

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Fallas Marietha

2007-05-01

Full Text Available Abstract Background We are conducting a genetic study of autism in the isolated population of the Central Valley of Costa Rica (CVCR. A novel Neuregulin 1 (NRG1 missense variant (exon 11 G>T was recently associated with psychosis and schizophrenia (SCZ in the same population isolate. Methods We genotyped the NRG1 exon 11 missense variant in 146 cases with autism, or autism spectrum disorder, with CVCR ancestry, and both parents when available (N = 267 parents from 143 independent families. Additional microsatellites were genotyped to examine haplotypes bearing the exon 11 variant. Results The NRG1 exon 11 G>T variant was found in 4/146 cases including one de novo occurrence. The frequency of the variant in case chromosomes was 0.014 and 0.045 in the parental non-transmitted chromosomes. At least 6 haplotypes extending 0.229 Mb were associated with the T allele. Three independent individuals, with no personal or family history of psychiatric disorder, shared at least a 1 megabase haplotype 5' to the T allele. Conclusion The NRG1 exon 11 missense variant is not associated with autism in the CVCR.

Semiparametric Allelic Tests for Mapping Multiple Phenotypes: Binomial Regression and Mahalanobis Distance.

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Majumdar, Arunabha; Witte, John S; Ghosh, Saurabh

2015-12-01

Binary phenotypes commonly arise due to multiple underlying quantitative precursors and genetic variants may impact multiple traits in a pleiotropic manner. Hence, simultaneously analyzing such correlated traits may be more powerful than analyzing individual traits. Various genotype-level methods, e.g., MultiPhen (O'Reilly et al. []), have been developed to identify genetic factors underlying a multivariate phenotype. For univariate phenotypes, the usefulness and applicability of allele-level tests have been investigated. The test of allele frequency difference among cases and controls is commonly used for mapping case-control association. However, allelic methods for multivariate association mapping have not been studied much. In this article, we explore two allelic tests of multivariate association: one using a Binomial regression model based on inverted regression of genotype on phenotype (Binomial regression-based Association of Multivariate Phenotypes [BAMP]), and the other employing the Mahalanobis distance between two sample means of the multivariate phenotype vector for two alleles at a single-nucleotide polymorphism (Distance-based Association of Multivariate Phenotypes [DAMP]). These methods can incorporate both discrete and continuous phenotypes. Some theoretical properties for BAMP are studied. Using simulations, the power of the methods for detecting multivariate association is compared with the genotype-level test MultiPhen's. The allelic tests yield marginally higher power than MultiPhen for multivariate phenotypes. For one/two binary traits under recessive mode of inheritance, allelic tests are found to be substantially more powerful. All three tests are applied to two different real data and the results offer some support for the simulation study. We propose a hybrid approach for testing multivariate association that implements MultiPhen when Hardy-Weinberg Equilibrium (HWE) is violated and BAMP otherwise, because the allelic approaches assume HWE

Association of autoimmune Addison's disease with alleles of STAT4 and GATA3 in European cohorts.

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Anna L Mitchell

Full Text Available Gene variants known to contribute to Autoimmune Addison's disease (AAD susceptibility include those at the MHC, MICA, CIITA, CTLA4, PTPN22, CYP27B1, NLRP-1 and CD274 loci. The majority of the genetic component to disease susceptibility has yet to be accounted for.To investigate the role of 19 candidate genes in AAD susceptibility in six European case-control cohorts.A sequential association study design was employed with genotyping using Sequenom iPlex technology. In phase one, 85 SNPs in 19 genes were genotyped in UK and Norwegian AAD cohorts (691 AAD, 715 controls. In phase two, 21 SNPs in 11 genes were genotyped in German, Swedish, Italian and Polish cohorts (1264 AAD, 1221 controls. In phase three, to explore association of GATA3 polymorphisms with AAD and to determine if this association extended to other autoimmune conditions, 15 SNPs in GATA3 were studied in UK and Norwegian AAD cohorts, 1195 type 1 diabetes patients from Norway, 650 rheumatoid arthritis patients from New Zealand and in 283 UK Graves' disease patients. Meta-analysis was used to compare genotype frequencies between the participating centres, allowing for heterogeneity.We report significant association with alleles of two STAT4 markers in AAD cohorts (rs4274624: P = 0.00016; rs10931481: P = 0.0007. In addition, nominal association of AAD with alleles at GATA3 was found in 3 patient cohorts and supported by meta-analysis. Association of AAD with CYP27B1 alleles was also confirmed, which replicates previous published data. Finally, nominal association was found at SNPs in both the NF-κB1 and IL23A genes in the UK and Italian cohorts respectively.Variants in the STAT4 gene, previously associated with other autoimmune conditions, confer susceptibility to AAD. Additionally, we report association of GATA3 variants with AAD: this adds to the recent report of association of GATA3 variants with rheumatoid arthritis.

Specific Silencing of L392V PSEN1 Mutant Allele by RNA Interference

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Malgorzata Sierant

2011-01-01

Full Text Available RNA interference (RNAi technology provides a powerful molecular tool to reduce an expression of selected genes in eukaryotic cells. Short interfering RNAs (siRNAs are the effector molecules that trigger RNAi. Here, we describe siRNAs that discriminate between the wild type and mutant (1174 C→G alleles of human Presenilin1 gene (PSEN1. This mutation, resulting in L392V PSEN1 variant, contributes to early onset familial Alzheimer's disease. Using the dual fluorescence assay, flow cytometry and fluorescent microscopy we identified positions 8th–11th, within the central part of the antisense strand, as the most sensitive to mismatches. 2-Thiouridine chemical modification introduced at the 3′-end of the antisense strand improved the allele discrimination, but wobble base pairing adjacent to the mutation site abolished the siRNA activity. Our data indicate that siRNAs can be designed to discriminate between the wild type and mutant alleles of genes that differ by just a single nucleotide.

DNA Methylation Analysis of BRD1 Promoter Regions and the Schizophrenia rs138880 Risk Allele.

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Mads Dyrvig

Full Text Available The bromodomain containing 1 gene, BRD1 is essential for embryogenesis and CNS development. It encodes a protein that participates in histone modifying complexes and thereby regulates the expression of a large number of genes. Genetic variants in the BRD1 locus show association with schizophrenia and bipolar disorder and risk alleles in the promoter region correlate with reduced BRD1 expression. Insights into the transcriptional regulation of BRD1 and the pathogenic mechanisms associated with BRD1 risk variants, however, remain sparse. By studying transcripts in human HeLa and SH-SY5Y cells we provide evidence for differences in relative expression of BRD1 transcripts with three alternative 5' UTRs (exon 1C, 1B, and 1A. We further show that expression of these transcript variants covaries negatively with DNA methylation proportions in their upstream promoter regions suggesting that promoter usage might be regulated by DNA methylation. In line with findings that the risk allele of the rs138880 SNP in the BRD1 promoter region correlates with reduced BRD1 expression, we find that it is also associated with moderate regional BRD1 promoter hypermethylation in both adipose tissue and blood. Importantly, we demonstrate by inspecting available DNA methylation and expression data that these regions undergo changes in methylation during fetal brain development and that differences in their methylation proportions in fetal compared to postnatal frontal cortex correlate significantly with BRD1 expression. These findings suggest that BRD1 may be dysregulated in both the developing and mature brain of risk allele carriers. Finally, we demonstrate that commonly used mood stabilizers Lithium, Valproate, and Carbamazepine affect the expression of BRD1 in SH-SY5Y cells. Altogether this study indicates a link between genetic risk and epigenetic dysregulation of BRD1 which raises interesting perspectives for targeting the mechanisms pharmacologically.

The Germline MLH1 K618A Variant and Susceptibility to Lynch Syndrome-Associated Tumors

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Medeiros, Fabiola; Lindor, Noralane M.; Couch, Fergus J.; Highsmith, W. Edward

2013-01-01

Missense variants discovered during sequencing of cancer susceptibility genes can be problematic for clinical interpretation. MLH1 K618A, which results from a 2-bp alteration (AAG→GCG) leading to a substitution of lysine to alanine in codon 618, has variously been interpreted as a pathogenic mutation, a variant of unknown significance, and a benign polymorphism. We evaluated the role of MLH1 K618A in predisposition to cancer by genotyping 1512 control subjects to assess its frequency in the general population. We also reviewed the literature concerning MLH1 K618A in families with colorectal cancer. The measured allele frequency of the K618A variant was 0.40%, which is remarkably close to the 0.44% summarized from 2491 control subjects in the literature. K618A was over-represented in families with suspected Lynch syndrome. In 1366 families, the allele frequency was 0.88% (OR = 2.1, 95% CI = 1.3 to 3.5; P = 0.006). In studies of sporadic cancers of the type associated with Lynch syndrome, K618A was over-represented in 1742 cases (allele frequency of 0.83) (OR = 2.0, 95% CI = 1.2 to 3.2; P = 0.008). We conclude that MLH1 K618A is not a fully penetrant Lynch syndrome mutation, although it is not without effect, appearing to increase the risk of Lynch syndrome-associated tumors approximately twofold. Our systematic assessment approach may be useful for variants in other genes. PMID:22426235

Incomplete dominance of deleterious alleles contributes substantially to trait variation and heterosis in maize.

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Jinliang Yang

2017-09-01

Full Text Available Deleterious alleles have long been proposed to play an important role in patterning phenotypic variation and are central to commonly held ideas explaining the hybrid vigor observed in the offspring of a cross between two inbred parents. We test these ideas using evolutionary measures of sequence conservation to ask whether incorporating information about putatively deleterious alleles can inform genomic selection (GS models and improve phenotypic prediction. We measured a number of agronomic traits in both the inbred parents and hybrids of an elite maize partial diallel population and re-sequenced the parents of the population. Inbred elite maize lines vary for more than 350,000 putatively deleterious sites, but show a lower burden of such sites than a comparable set of traditional landraces. Our modeling reveals widespread evidence for incomplete dominance at these loci, and supports theoretical models that more damaging variants are usually more recessive. We identify haplotype blocks using an identity-by-decent (IBD analysis and perform genomic prediction analyses in which we weigh blocks on the basis of complementation for segregating putatively deleterious variants. Cross-validation results show that incorporating sequence conservation in genomic selection improves prediction accuracy for grain yield and other fitness-related traits as well as heterosis for those traits. Our results provide empirical support for an important role for incomplete dominance of deleterious alleles in explaining heterosis and demonstrate the utility of incorporating functional annotation in phenotypic prediction and plant breeding.

Incomplete dominance of deleterious alleles contributes substantially to trait variation and heterosis in maize.

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Yang, Jinliang; Mezmouk, Sofiane; Baumgarten, Andy; Buckler, Edward S; Guill, Katherine E; McMullen, Michael D; Mumm, Rita H; Ross-Ibarra, Jeffrey

2017-09-01

Deleterious alleles have long been proposed to play an important role in patterning phenotypic variation and are central to commonly held ideas explaining the hybrid vigor observed in the offspring of a cross between two inbred parents. We test these ideas using evolutionary measures of sequence conservation to ask whether incorporating information about putatively deleterious alleles can inform genomic selection (GS) models and improve phenotypic prediction. We measured a number of agronomic traits in both the inbred parents and hybrids of an elite maize partial diallel population and re-sequenced the parents of the population. Inbred elite maize lines vary for more than 350,000 putatively deleterious sites, but show a lower burden of such sites than a comparable set of traditional landraces. Our modeling reveals widespread evidence for incomplete dominance at these loci, and supports theoretical models that more damaging variants are usually more recessive. We identify haplotype blocks using an identity-by-decent (IBD) analysis and perform genomic prediction analyses in which we weigh blocks on the basis of complementation for segregating putatively deleterious variants. Cross-validation results show that incorporating sequence conservation in genomic selection improves prediction accuracy for grain yield and other fitness-related traits as well as heterosis for those traits. Our results provide empirical support for an important role for incomplete dominance of deleterious alleles in explaining heterosis and demonstrate the utility of incorporating functional annotation in phenotypic prediction and plant breeding.

GCKR variants increase triglycerides while protecting from insulin resistance in Chinese children.

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Shen, Yue; Wu, Lijun; Xi, Bo; Liu, Xin; Zhao, Xiaoyuan; Cheng, Hong; Hou, Dongqing; Wang, Xingyu; Mi, Jie

2013-01-01

Variants in gene encoding glucokinase regulator protein (GCKR) were found to have converse effects on triglycerides and glucose metabolic traits. We aimed to investigate the influence of GCKR variants for triglycerides and glucose metabolic traits in Chinese children and adults. We genotyped two GCKR variants rs1260326 and rs1260333 in children and adults, and analyzed the association between two variants and triglycerides, glucose, insulin and HOMA-IR using linear regression model, and estimated the effect on insulin resistance using logistic regression model. Rs1260326 and rs1260333 associated with increased triglycerides in children and adults (ptriglycerides in Chinese children and adults. Triglycerides-increasing alleles of GCKR variants reduce insulin and HOMA-IR index, and protect from insulin resistance in children. Our results suggested GCKR has an effect on development of insulin resistance in Chinese children.

DCLK1 variants are associated across schizophrenia and attention deficit/hyperactivity disorder

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Håvik, Bjarte; Degenhardt, Franziska A; Johansson, Stefan

2012-01-01

that have neuro-cognitive dysfunctions: schizophrenia (SCZ), bipolar affective disorder (BP) and attention deficit/hyperactivity disorder (ADHD). We mined six genome wide association studies (GWASs) that were available publically or through collaboration; three for BP, two for SCZ and one for ADHD. We also......Doublecortin and calmodulin like kinase 1 (DCLK1) is implicated in synaptic plasticity and neurodevelopment. Genetic variants in DCLK1 are associated with cognitive traits, specifically verbal memory and general cognition. We investigated the role of DCLK1 variants in three psychiatric disorders...

Allele frequencies of variants in ultra conserved elements identify selective pressure on transcription factor binding.

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Silla, Toomas; Kepp, Katrin; Tai, E Shyong; Goh, Liang; Davila, Sonia; Catela Ivkovic, Tina; Calin, George A; Voorhoeve, P Mathijs

2014-01-01

Ultra-conserved genes or elements (UCGs/UCEs) in the human genome are extreme examples of conservation. We characterized natural variations in 2884 UCEs and UCGs in two distinct populations; Singaporean Chinese (n = 280) and Italian (n = 501) by using a pooled sample, targeted capture, sequencing approach. We identify, with high confidence, in these regions the abundance of rare SNVs (MAFpower for association studies. By combining our data with 1000 Genome Project data, we show in three independent datasets that prevalent UCE variants (MAF>5%) are more often found in relatively less-conserved nucleotides within UCEs, compared to rare variants. Moreover, prevalent variants are less likely to overlap transcription factor binding site. Using SNPfold we found no significant influence of RNA secondary structure on UCE conservation. All together, these results suggest UCEs are not under selective pressure as a stretch of DNA but are under differential evolutionary pressure on the single nucleotide level.

Common genetic variants and modification of penetrance of BRCA2-associated breast cancer.

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Mia M Gaudet

2010-10-01

Full Text Available The considerable uncertainty regarding cancer risks associated with inherited mutations of BRCA2 is due to unknown factors. To investigate whether common genetic variants modify penetrance for BRCA2 mutation carriers, we undertook a two-staged genome-wide association study in BRCA2 mutation carriers. In stage 1 using the Affymetrix 6.0 platform, 592,163 filtered SNPs genotyped were available on 899 young (<40 years affected and 804 unaffected carriers of European ancestry. Associations were evaluated using a survival-based score test adjusted for familial correlations and stratified by country of the study and BRCA2*6174delT mutation status. The genomic inflation factor (λ was 1.011. The stage 1 association analysis revealed multiple variants associated with breast cancer risk: 3 SNPs had p-values<10(-5 and 39 SNPs had p-values<10(-4. These variants included several previously associated with sporadic breast cancer risk and two novel loci on chromosome 20 (rs311499 and chromosome 10 (rs16917302. The chromosome 10 locus was in ZNF365, which contains another variant that has recently been associated with breast cancer in an independent study of unselected cases. In stage 2, the top 85 loci from stage 1 were genotyped in 1,264 cases and 1,222 controls. Hazard ratios (HR and 95% confidence intervals (CI for stage 1 and 2 were combined and estimated using a retrospective likelihood approach, stratified by country of residence and the most common mutation, BRCA2*6174delT. The combined per allele HR of the minor allele for the novel loci rs16917302 was 0.75 (95% CI 0.66-0.86, and for rs311499 was 0.72 (95% CI 0.61-0.85, . FGFR2 rs2981575 had the strongest association with breast cancer risk (per allele HR = 1.28, 95% CI 1.18-1.39, . These results indicate that SNPs that modify BRCA2 penetrance identified by an agnostic approach thus far are limited to variants that also modify risk of sporadic BRCA2 wild-type breast cancer.

Disrupted functional and structural networks in cognitively normal elderly subjects with the APOE ɛ4 allele.

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Chen, Yaojing; Chen, Kewei; Zhang, Junying; Li, Xin; Shu, Ni; Wang, Jun; Zhang, Zhanjun; Reiman, Eric M

2015-03-13

As the Apolipoprotein E (APOE) ɛ4 allele is a major genetic risk factor for sporadic Alzheimer's disease (AD), which has been suggested as a disconnection syndrome manifested by the disruption of white matter (WM) integrity and functional connectivity (FC), elucidating the subtle brain structural and functional network changes in cognitively normal ɛ4 carriers is essential for identifying sensitive neuroimaging based biomarkers and understanding the preclinical AD-related abnormality development. We first constructed functional network on the basis of resting-state functional magnetic resonance imaging and a structural network on the basis of diffusion tensor image. Using global, local and nodal efficiencies of these two networks, we then examined (i) the differences of functional and WM structural network between cognitively normal ɛ4 carriers and non-carriers simultaneously, (ii) the sensitivity of these indices as biomarkers, and (iii) their relationship to behavior measurements, as well as to cholesterol level. For ɛ4 carriers, we found reduced global efficiency significantly in WM and marginally in FC, regional FC dysfunctions mainly in medial temporal areas, and more widespread for WM network. Importantly, the right parahippocampal gyrus (PHG.R) was the only region with simultaneous functional and structural damage, and the nodal efficiency of PHG.R in WM network mediates the APOE ɛ4 effect on memory function. Finally, the cholesterol level correlated with WM network differently than with the functional network in ɛ4 carriers. Our results demonstrated ɛ4-specific abnormal structural and functional patterns, which may potentially serve as biomarkers for early detection before the onset of the disease.

A high incidence of polymorphic CYP2C19 variants in archival blood samples from Papua New Guinea

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Hsu Huai-Ling

2008-09-01

Full Text Available Abstract There is considerable inter-ethnic variability in the incidence of CYP2C19 genetic poor metabolisers (var/var. About 3 per cent of Caucasians are CYP2C19 var/var. By contrast, an extremely high incidence (70 per cent is observed in the Melanesian island of Vanuatu. The colonisation of the Pacific Islands is believed to have involved migration through Papua New Guinea (PNG, and hence a high incidence may also be expected in this population. The reported incidence in PNG was only 36 per cent, however. PNG is a country of extensive ethnic diversity, and the incidence of the CYP2C19 var/var in other regional populations of PNG is currently not established. In this study, restriction fragment length polymorphism-polymerase chain reaction analysis of archival blood serum samples was used to determine the prevalence of the CYP2C19*2 and *3 variant alleles in three different ethnic and geographically isolated populations of PNG. In the largest population studied (Iruna, the frequency of both variant CYP2C19 alleles was high (0.37 and 0.34, respectively. Specifically, the frequency of the CYP2C19*3 allele was significantly higher than in the PNG (East Sepik population reported previously (0.34 vs 0.16; p 0.0001. In the Iruna population, 48.9 per cent of the samples were homozygous variants for CYP2C19*2 or *3, which although higher was not statistically different from the East Sepik population (36 per cent. The results of this study indicated that other regional populations of PNG also have a relatively high incidence of the CYP2C19 genetic polymorphism compared with Caucasian populations. The high incidence reported in Vanuatu, however, may be due to genetic drift rather than a PNG founder population, as the Vanuatu population is dominated by the CYP2C19*2 allele, with a lower contribution from the *3 allelic variant.

Prevalence of Huntington's disease gene CAG trinucleotide repeat alleles in patients with bipolar disorder.

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Ramos, Eliana Marisa; Gillis, Tammy; Mysore, Jayalakshmi S; Lee, Jong-Min; Alonso, Isabel; Gusella, James F; Smoller, Jordan W; Sklar, Pamela; MacDonald, Marcy E; Perlis, Roy H

2015-06-01

Huntington's disease is a neurodegenerative disorder characterized by motor, cognitive, and psychiatric symptoms that are caused by huntingtin gene (HTT) CAG trinucleotide repeat alleles of 36 or more units. A greater than expected prevalence of incompletely penetrant HTT CAG repeat alleles observed among individuals diagnosed with major depressive disorder raises the possibility that another mood disorder, bipolar disorder, could likewise be associated with Huntington's disease. We assessed the distribution of HTT CAG repeat alleles in a cohort of individuals with bipolar disorder. HTT CAG allele sizes from 2,229 Caucasian individuals diagnosed with DSM-IV bipolar disorder were compared to allele sizes in 1,828 control individuals from multiple cohorts. We found that HTT CAG repeat alleles > 35 units were observed in only one of 4,458 chromosomes from individuals with bipolar disorder, compared to three of 3,656 chromosomes from control subjects. These findings do not support an association between bipolar disorder and Huntington's disease. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Evaluation of regulatory genetic variants in POU5F1 and risk of congenital heart disease in Han Chinese.

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Lin, Yuan; Ding, Chenyue; Zhang, Kai; Ni, Bixian; Da, Min; Hu, Liang; Hu, Yuanli; Xu, Jing; Wang, Xiaowei; Chen, Yijiang; Mo, Xuming; Cui, Yugui; Shen, Hongbing; Sha, Jiahao; Liu, Jiayin; Hu, Zhibin

2015-10-28

OCT4 is a transcription factor of the POU family, which plays a key role in embryonic development and stem cell pluripotency. Previous studies have shown that Oct4 is required for cardiomyocyte differentiation in mice and its depletion could result in cardiac morphogenesis in embryo. However, whether the genetic variations in OCT4 coding gene, POU5F1, confer the predisposition to congenital heart disease (CHD) is unclear. This study sought to investigate the associations between low-frequency (defined here as having minor allele frequency (MAF) between 0.1%-5%) and rare (MAF below 0.1%) variants with potential function in POU5F1 and risk of CHD. We conducted association analysis in a two-stage case-control study with a total of 2,720 CHD cases and 3,331 controls in Chinese. The low-frequency variant rs3130933 was observed to be associated with a significantly increased risk of CHD [additive model: adjusted odds ratio (OR) = 2.15, adjusted P = 3.37 × 10(-6)]. Furthermore, luciferase activity assay showed that the variant A allele led to significantly lower expression levels as compared to the G allele. These findings indicate for the first time that low-frequency functional variant in POU5F1 may contribute to the risk of congenital heart malformations.

Evaluation of regulatory genetic variants in POU5F1 and risk of congenital heart disease in Han Chinese

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Lin, Yuan; Ding, Chenyue; Zhang, Kai; Ni, Bixian; da, Min; Hu, Liang; Hu, Yuanli; Xu, Jing; Wang, Xiaowei; Chen, Yijiang; Mo, Xuming; Cui, Yugui; Shen, Hongbing; Sha, Jiahao; Liu, Jiayin; Hu, Zhibin

2015-10-01

OCT4 is a transcription factor of the POU family, which plays a key role in embryonic development and stem cell pluripotency. Previous studies have shown that Oct4 is required for cardiomyocyte differentiation in mice and its depletion could result in cardiac morphogenesis in embryo. However, whether the genetic variations in OCT4 coding gene, POU5F1, confer the predisposition to congenital heart disease (CHD) is unclear. This study sought to investigate the associations between low-frequency (defined here as having minor allele frequency (MAF) between 0.1%-5%) and rare (MAF below 0.1%) variants with potential function in POU5F1 and risk of CHD. We conducted association analysis in a two-stage case-control study with a total of 2,720 CHD cases and 3,331 controls in Chinese. The low-frequency variant rs3130933 was observed to be associated with a significantly increased risk of CHD [additive model: adjusted odds ratio (OR) = 2.15, adjusted P = 3.37 × 10-6]. Furthermore, luciferase activity assay showed that the variant A allele led to significantly lower expression levels as compared to the G allele. These findings indicate for the first time that low-frequency functional variant in POU5F1 may contribute to the risk of congenital heart malformations.

The M405V allele of the glutaryl-CoA dehydrogenase gene is an important marker for glutaric aciduria type I (GA-I) low excretors.

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Schillaci, Lori-Anne P; Greene, Carol L; Strovel, Erin; Rispoli-Joines, Jessica; Spector, Elaine; Woontner, Michael; Scharer, Gunter; Enns, Gregory M; Gallagher, Renata; Zinn, Arthur B; McCandless, Shawn E; Hoppel, Charles L; Goodman, Stephen I; Bedoyan, Jirair K

2016-09-01

Glutaric aciduria type I (GA-I) is an autosomal recessive organic aciduria resulting from a functional deficiency of glutaryl-CoA dehydrogenase, encoded by GCDH. Two clinically indistinguishable diagnostic subgroups of GA-I are known; low and high excretors (LEs and HEs, respectively). Early medical and dietary interventions can result in significantly better outcomes and improved quality of life for patients with GA-I. We report on nine cases of GA-I LE patients all sharing the M405V allele with two cases missed by newborn screening (NBS) using tandem mass spectrometry (MS/MS). We describe a novel case with the known pathogenic M405V variant and a novel V133L variant, and present updated and previously unreported clinical, biochemical, functional and molecular data on eight other patients all sharing the M405V allele. Three of the nine patients are of African American ancestry, with two as siblings. GCDH activity was assayed in six of the nine patients and varied from 4 to 25% of the control mean. We support the use of urine glutarylcarnitine as a biochemical marker of GA-I by demonstrating that glutarylcarnitine is efficiently cleared by the kidney (50-90%) and that plasma and urine glutarylcarnitine follow a linear relationship. We report the allele frequencies for three known GA-I LE GCDH variants (M405V, V400M and R227P) and note that both the M405V and V400M variants are significantly more common in the population of African ancestry compared to the general population. This report highlights the M405V allele as another important molecular marker in patients with the GA-I LE phenotype. Therefore, the incorporation into newborn screening of molecular screening for the M405V and V400M variants in conjunction with MS/MS could help identify asymptomatic at-risk GA-I LE patients that could potentially be missed by current NBS programs. Copyright © 2016 Elsevier Inc. All rights reserved.

RareVar: A Framework for Detecting Low-Frequency Single-Nucleotide Variants.

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Hao, Yangyang; Xuei, Xiaoling; Li, Lang; Nakshatri, Harikrishna; Edenberg, Howard J; Liu, Yunlong

2017-07-01

Accurate identification of low-frequency somatic point mutations in tumor samples has important clinical utilities. Although high-throughput sequencing technology enables capturing such variants while sequencing primary tumor samples, our ability for accurate detection is compromised when the variant frequency is close to the sequencer error rate. Most current experimental and bioinformatic strategies target mutations with ≥5% allele frequency, which limits our ability to understand the cancer etiology and tumor evolution. We present an experimental and computational modeling framework, RareVar, to reliably identify low-frequency single-nucleotide variants from high-throughput sequencing data under standard experimental protocols. RareVar protocol includes a benchmark design by pooling DNAs from already sequenced individuals at various concentrations to target variants at desired frequencies, 0.5%-3% in our case. By applying a generalized, linear model-based, position-specific error model, followed by machine-learning-based variant calibration, our approach outperforms existing methods. Our method can be applied on most capture and sequencing platforms without modifying the experimental protocol.

Discovery and functional annotation of SIX6 variants in primary open-angle glaucoma.

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Megan Ulmer Carnes

Full Text Available Glaucoma is a leading cause of blindness worldwide. Primary open-angle glaucoma (POAG is the most common subtype and is a complex trait with multigenic inheritance. Genome-wide association studies have previously identified a significant association between POAG and the SIX6 locus (rs10483727, odds ratio (OR = 1.32, p = 3.87×10(-11. SIX6 plays a role in ocular development and has been associated with the morphology of the optic nerve. We sequenced the SIX6 coding and regulatory regions in 262 POAG cases and 256 controls and identified six nonsynonymous coding variants, including five rare and one common variant, Asn141His (rs33912345, which was associated significantly with POAG (OR = 1.27, p = 4.2×10(-10 in the NEIGHBOR/GLAUGEN datasets. These variants were tested in an in vivo Danio rerio (zebrafish complementation assay to evaluate ocular metrics such as eye size and optic nerve structure. Five variants, found primarily in POAG cases, were hypomorphic or null, while the sixth variant, found only in controls, was benign. One variant in the SIX6 enhancer increased expression of SIX6 and disrupted its regulation. Finally, to our knowledge for the first time, we have identified a clinical feature in POAG patients that appears to be dependent upon SIX6 genotype: patients who are homozygous for the SIX6 risk allele (His141 have a statistically thinner retinal nerve fiber layer than patients homozygous for the SIX6 non-risk allele (Asn141. Our results, in combination with previous SIX6 work, lead us to hypothesize that SIX6 risk variants disrupt the development of the neural retina, leading to a reduced number of retinal ganglion cells, thereby increasing the risk of glaucoma-associated vision loss.

Genetic variants influencing phenotypic variance heterogeneity.

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Ek, Weronica E; Rask-Andersen, Mathias; Karlsson, Torgny; Enroth, Stefan; Gyllensten, Ulf; Johansson, Åsa

2018-03-01

Most genetic studies identify genetic variants associated with disease risk or with the mean value of a quantitative trait. More rarely, genetic variants associated with variance heterogeneity are considered. In this study, we have identified such variance single-nucleotide polymorphisms (vSNPs) and examined if these represent biological gene × gene or gene × environment interactions or statistical artifacts caused by multiple linked genetic variants influencing the same phenotype. We have performed a genome-wide study, to identify vSNPs associated with variance heterogeneity in DNA methylation levels. Genotype data from over 10 million single-nucleotide polymorphisms (SNPs), and DNA methylation levels at over 430 000 CpG sites, were analyzed in 729 individuals. We identified vSNPs for 7195 CpG sites (P mean DNA methylation levels. We further showed that variance heterogeneity between genotypes mainly represents additional, often rare, SNPs in linkage disequilibrium (LD) with the respective vSNP and for some vSNPs, multiple low frequency variants co-segregating with one of the vSNP alleles. Therefore, our results suggest that variance heterogeneity of DNA methylation mainly represents phenotypic effects by multiple SNPs, rather than biological interactions. Such effects may also be important for interpreting variance heterogeneity of more complex clinical phenotypes.

Analysis of IL12B gene variants in inflammatory bowel disease.

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Jürgen Glas

Full Text Available BACKGROUND: IL12B encodes the p40 subunit of IL-12, which is also part of IL-23. Recent genome-wide association studies identified IL12B and IL23R as susceptibility genes for inflammatory bowel disease (IBD. However, the phenotypic effects and potential gene-gene interactions of IL12B variants are largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed IL12B gene variants regarding association with Crohn's disease (CD and ulcerative colitis (UC. Genomic DNA from 2196 individuals including 913 CD patients, 318 UC patients and 965 healthy, unrelated controls was analyzed for four SNPs in the IL12B gene region (rs3212227, rs17860508, rs10045431, rs6887695. Our analysis revealed an association of the IL12B SNP rs6887695 with susceptibility to IBD (p = 0.035; OR 1.15 [95% CI 1.01-1.31] including a trend for rs6887695 for association with CD (OR 1.41; [0.99-1.31], p = 0.066 and UC (OR 1.18 [0.97-1.43], p = 0.092. CD patients, who were homozygous C/C carriers of this SNP, had significantly more often non-stricturing, non-penetrating disease than carriers of the G allele (p = 6.8×10(-5; OR = 2.84, 95% CI 1.66-4.84, while C/C homozygous UC patients had less often extensive colitis than G allele carriers (p = 0.029; OR = 0.36, 95% CI 0.14-0.92. In silico analysis predicted stronger binding of the minor C allele of rs6887695 to the transcription factor RORα which is involved in Th17 differentiation. Differences regarding the binding to the major and minor allele sequence of rs6887695 were also predicted for the transcription factors HSF1, HSF2, MZF1 and Oct-1. Epistasis analysis revealed weak epistasis of the IL12B SNP rs6887695 with several SNPs (rs11889341, rs7574865, rs7568275, rs8179673, rs10181656, rs7582694 in the STAT4 gene which encodes the major IL-12 downstream transcription factor STAT4 (p<0.05 but there was no epistasis between IL23R and IL12B variants. CONCLUSIONS/SIGNIFICANCE: The IL12B SNP rs6887695

An SSP-PCR method for the rapid detection of disease-associated alleles HLA-A*29 and HLA-B*51.

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Amstutz, U; Schaerer, D; Andrey, G; Wirthmueller, U; Largiadèr, C R

2018-05-15

HLA-A*29 and HLA-B*51 are associated with birdshot uveitis and Behçet's disease, respectively, and are used as a diagnostic criterion in patients with suspected disease, requiring their detection in diagnostic laboratories. While commercial tests for individual HLA alleles are available for other disease-associated HLA variants, no similar allele-specific assays are available for HLA-A*29 and -B*51. Here, we report SSP-PCR methods for the detection of HLA-A*29 and -B*51 using a single PCR reaction per allele. The assays were tested in 30 and 32 previously HLA-typed samples, respectively, representing >97% of HLA-A alleles and >93% of HLA-B alleles in a European population. A concordance of 100% was observed with previous typing results, validating these methods for use in a diagnostic or research context. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Psoriasis Patients Are Enriched for Genetic Variants That Protect against HIV-1 Disease

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Chen, Haoyan; Hayashi, Genki; Lai, Olivia Y.; Dilthey, Alexander; Kuebler, Peter J.; Wong, Tami V.; Martin, Maureen P.; Fernandez Vina, Marcelo A.; McVean, Gil; Wabl, Matthias; Leslie, Kieron S.; Maurer, Toby; Martin, Jeffrey N.; Deeks, Steven G.; Carrington, Mary; Bowcock, Anne M.; Nixon, Douglas F.; Liao, Wilson

2012-01-01

An important paradigm in evolutionary genetics is that of a delicate balance between genetic variants that favorably boost host control of infection but which may unfavorably increase susceptibility to autoimmune disease. Here, we investigated whether patients with psoriasis, a common immune-mediated disease of the skin, are enriched for genetic variants that limit the ability of HIV-1 virus to replicate after infection. We analyzed the HLA class I and class II alleles of 1,727 Caucasian psoriasis cases and 3,581 controls and found that psoriasis patients are significantly more likely than controls to have gene variants that are protective against HIV-1 disease. This includes several HLA class I alleles associated with HIV-1 control; amino acid residues at HLA-B positions 67, 70, and 97 that mediate HIV-1 peptide binding; and the deletion polymorphism rs67384697 associated with high surface expression of HLA-C. We also found that the compound genotype KIR3DS1 plus HLA-B Bw4-80I, which respectively encode a natural killer cell activating receptor and its putative ligand, significantly increased psoriasis susceptibility. This compound genotype has also been associated with delay of progression to AIDS. Together, our results suggest that genetic variants that contribute to anti-viral immunity may predispose to the development of psoriasis. PMID:22577363

Prion protein genotype survey confirms low frequency of scrapie-resistant K222 allele in British goat herds.

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Goldmann, W; Marier, E; Stewart, P; Konold, T; Street, S; Langeveld, J; Windl, O; Ortiz-Pelaez, A

2016-02-13

Scrapie in goats is a transmissible, fatal prion disease, which is endemic in the British goat population. The recent success in defining caprine PRNP gene variants that provide resistance to experimental and natural classical scrapie has prompted the authors to conduct a survey of PRNP genotypes in 10 goat breeds and 52 herds to find goats with the resistant K222 allele. They report here the frequencies in 1236 tested animals of the resistance-associated K222 and several other alleles by breed and herd. Eight animals were found to be heterozygous QK222 goats (0.64 per cent genotype frequency, 95 per cent CI 0.28 to 1.27 per cent) but no homozygous KK222 goats were detected. The K222 allele was found in Saanen, Toggenburg and Anglo-Nubian goats. The fact that only a few goats with the K222 allele have been identified does not preclude the possibility to design and implement successful breeding programmes at national level. British Veterinary Association.

Multiple genetic variants associated with posttransplantation diabetes mellitus in Chinese Han populations.

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Chen, Jie; Li, Lixin; An, Yunfei; Zhang, Junlong; Liao, Yun; Li, Yi; Wang, Lanlan

2018-03-01

Posttransplantation diabetes mellitus (PTDM) is a major complication after solid organ transplantation. This study is to investigate the association of nine genetic variant factors and PTDM in Chinese Han patients. HLA-DP (rs3077, rs9277535), HLA-DQ (rs7453920), signal transducer and activator of transcription 4 (STAT4) (rs7574865), IL-28B (rs12979860, rs8099917, and rs12980275), and IL-18 (rs1946518 and rs187238) were investigated in 260 liver transplant recipients (PTDM vs non-PTDM) by high-resolution melting curve analysis. Serum interleukin (IL)-1β, IL-6, IL-8, IL-17, interferon-γ, inducible protein-10, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1b were analyzed by a Bio-Plex suspension array system (Bio-Plex Multiplex Immunoassays, Bio-Rad, Hercules, CA, USA). Signal transducer and activator of transcription 4 (rs7574865) T allele and IL-18 (rs1946518) A allele increase the risk for insulin resistance and PTDM. Recipients with STAT4 (rs7574865) T allele are associated with an increased concentration of IL-1β, interferon-γ, monocyte chemoattractant protein, and macrophage inflammatory protein-1b. The genetic variants of STAT4 (rs7574865) and IL-18 (rs1946518) may be new important markers for PTDM. © 2017 Wiley Periodicals, Inc.

Eight further individuals with intellectual disability and epilepsy carrying bi-allelic CNTNAP2 aberrations allow delineation of the mutational and phenotypic spectrum.

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Smogavec, Mateja; Cleall, Alison; Hoyer, Juliane; Lederer, Damien; Nassogne, Marie-Cécile; Palmer, Elizabeth E; Deprez, Marie; Benoit, Valérie; Maystadt, Isabelle; Noakes, Charlotte; Leal, Alejandro; Shaw, Marie; Gecz, Jozef; Raymond, Lucy; Reis, André; Shears, Deborah; Brockmann, Knut; Zweier, Christiane

2016-12-01

Heterozygous copy number variants (CNVs) or sequence variants in the contactin-associated protein 2 gene CNTNAP2 have been discussed as risk factors for a wide spectrum of neurodevelopmental and neuropsychiatric disorders. Bi-allelic aberrations in this gene are causative for an autosomal-recessive disorder with epilepsy, severe intellectual disability (ID) and cortical dysplasia (CDFES). As the number of reported individuals is still limited, we aimed at a further characterisation of the full mutational and clinical spectrum. Targeted sequencing, chromosomal microarray analysis or multigene panel sequencing was performed in individuals with severe ID and epilepsy. We identified homozygous mutations, compound heterozygous CNVs or CNVs and mutations in CNTNAP2 in eight individuals from six unrelated families. All aberrations were inherited from healthy, heterozygous parents and are predicted to be deleterious for protein function. Epilepsy occurred in all affected individuals with onset in the first 3.5 years of life. Further common aspects were ID (severe in 6/8), regression of speech development (5/8) and behavioural anomalies (7/8). Interestingly, cognitive impairment in one of two affected brothers was, in comparison, relatively mild with good speech and simple writing abilities. Cortical dysplasia that was previously reported in CDFES was not present in MRIs of six individuals and only suspected in one. By identifying novel homozygous or compound heterozygous, deleterious CNVs and mutations in eight individuals from six unrelated families with moderate-to-severe ID, early onset epilepsy and behavioural anomalies, we considerably broaden the mutational and clinical spectrum associated with bi-allelic aberrations in CNTNAP2. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Distinct Niemann-Pick Disease Type C Clinical, Cytological, and Biochemical Phenotype in an Adult Patient With 1 Mutated, Overexpressed Allele

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Julia Jecel MD

2015-11-01

Full Text Available Niemann-Pick disease type C (NP-C is a rare autosomal-recessive neurovisceral lysosomal storage disease. We report on a juvenile onset, now 25-year-old female patient with typical neurologic symptoms, including vertical gaze palsy, of NP-C. The diagnosis was supported by a positive filipin test (“variant biochemical phenotype” of cholesterol accumulation in cultured fibroblasts, high numbers of “Niemann-Pick cells” in the bone marrow, and 1 positive out of 3 NP-C biomarkers tested, but NP-C was not definitely confirmed genetically. She showed only 1 known NPC1 variant (3 bp deletion in exon 18; p.N916del; this allele, however, being distinctly overexpressed at the messenger RNA level as compared to the wild-type allele, as a not as yet clarified (copathogenic? phenomenon. The patient’s mother, also carrying the p.N916del allele but without overexpression, has a chronic inflammatory disease of the central nervous system classified as multiple sclerosis. However, her severe clinical phenotype includes some signs also consistent with NP-C. The laboratory diagnosis of NP-C can be challenging in detecting novel disease constellations.

Association of CISH -292A/T genetic variant with hepatitis B virus infection.

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Tong, Hoang V; Toan, Nguyen L; Song, Le H; Kremsner, Peter G; Kun, Jürgen F J; Tp, Velavan

2012-04-01

Cytokine-inducible SRC homology 2 domain protein (CISH) is a suppressor of cytokine signaling that controls interleukin-2 signaling pathway. We investigated the single nucleotide polymorphism (SNP) -292A>T in 473 Vietnamese hepatitis B virus (HBV) carriers and 416 healthy controls. CISH variants at -292A>T were associated to HBV infection (Allelic: OR, 1.22 95% CI, 1-1.49; P = 0.04; Recessive: OR, 1.69 95% CI 1.23-2.54; P = 0.007). A gene dose effect for the risk allele -292T was observed (P = 0.04). The level of interleukin 2 and liver enzymes such as alanine transaminase, aspartate transaminase, total bilirubin, and direct bilirubin were not associated to CISH polymorphism at position -292A>T This study associated the vital role of CISH SNP -292A>T variant to hepatitis B virus infection in a Vietnamese population.

Habenular expression of rare missense variants of the β4 nicotinic receptor subunit alters nicotine consumption

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Marta A Ślimak

2014-01-01

Full Text Available The CHRNA5-CHRNA3-CHRNB4 gene cluster, encoding the α5, α3 and β4 nicotinic acetylcholine receptor (nAChR subunits, has been linked to nicotine dependence. The habenulo-interpeduncular (Hb-IPN tract is particularly enriched in α3β4 nAChRs. We recently showed that modulation of these receptors in the medial habenula (MHb in mice altered nicotine consumption. Given that β4 is rate-limiting for receptor activity and that single nucleotide polymorphisms (SNPs in CHRNB4 have been linked to altered risk of nicotine dependence in humans, we were interested in determining the contribution of allelic variants of β4 to nicotine receptor activity in the MHb. We screened for missense SNPs with allele frequencies > 0.0005 and introduced the corresponding substitutions in Chrnb4. Fourteen variants were analyzed by co-expression with α3. We found that β4A90I and β4T374I variants, previously shown to associate with reduced risk of smoking, and an additional variant β4D447Y, significantly increased nicotine-evoked current amplitudes, while β4R348C, the mutation most frequently encountered in sporadic amyotrophic lateral sclerosis (sALS, showed reduced nicotine currents. We employed lentiviruses to express β4 or β4 variants in the MHb. Immunoprecipitation studies confirmed that β4 lentiviral-mediated expression leads to specific upregulation of α3β4 but not β2 nAChRs in the Mhb. Mice injected with the β4-containing virus showed pronounced aversion to nicotine as previously observed in transgenic Tabac mice overexpressing Chrnb4 at endogenous sites including the MHb. Habenular expression of the β4 gain-of-function allele T374I also resulted in strong aversion, while transduction with the β4 loss-of function allele R348C failed to induce nicotine aversion. Altogether, these data confirm the critical role of habenular β4 in nicotine consumption, and identify specific SNPs in CHRNB4 that modify nicotine-elicited currents and alter nicotine

HFE p.C282Y gene variant is associated with varicose veins in Russian population.

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Sokolova, Ekaterina A; Shadrina, Alexandra S; Sevost'ianova, Kseniya S; Shevela, Andrey I; Soldatsky, Evgenii Yu; Seliverstov, Evgenii I; Demekhova, Marina Yu; Shonov, Oleg A; Ilyukhin, Evgenii A; Smetanina, Mariya A; Voronina, Elena N; Zolotukhin, Igor A; Filipenko, Maxim L

2016-08-01

Recently, the association of polymorphism rs1800562 (p.C282Y) in the hemochromatosis (HFE) gene with the increased risk of venous ulceration was shown. We hypothesized that HFE gene polymorphism might be involved not only in ulceration process, but also in susceptibility to primary varicose veins. We genotyped HFE p.C282Y (rs1800562) and p.H63D (rs1799945) variants in patients with primary varicose veins (n = 463) and in the control group (n = 754). In our study, p.282Y variant (rs1800562 A allele) was significantly associated with the risk of varicose veins (OR 1.79, 95 % CI = 1.11-2.89, P = 0.02). A borderline significant reverse association of p.63D variant (rs1799945 G allele) with venous leg ulcer development was revealed in Russians (OR 0.25, 95 % CI = 0.06-1.00, P = 0.05), but not in the meta-analysis (P = 0.56). We conclude that the HFE gene polymorphism can affect the risk of developing primary varicose veins.

Allelic variants of melanocortin 3 receptor gene (MC3R and weight loss in obesity: a randomised trial of hypo-energetic high- versus low-fat diets.

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José L Santos

Full Text Available INTRODUCTION: The melanocortin system plays an important role in energy homeostasis. Mice genetically deficient in the melanocortin-3 receptor gene have a normal body weight with increased body fat, mild hypophagia compared to wild-type mice. In humans, Thr6Lys and Val81Ile variants of the melanocortin-3 receptor gene (MC3R have been associated with childhood obesity, higher BMI Z-score and elevated body fat percentage compared to non-carriers. The aim of this study is to assess the association in adults between allelic variants of MC3R with weight loss induced by energy-restricted diets. SUBJECTS AND METHODS: This research is based on the NUGENOB study, a trial conducted to assess weight loss during a 10-week dietary intervention involving two different hypo-energetic (high-fat and low-fat diets. A total of 760 obese patients were genotyped for 10 single nucleotide polymorphisms covering the single exon of MC3R gene and its flanking regions, including the missense variants Thr6Lys and Val81Ile. Linear mixed models and haplotype-based analysis were carried out to assess the potential association between genetic polymorphisms and differential weight loss, fat mass loss, waist change and resting energy expenditure changes. RESULTS: No differences in drop-out rate were found by MC3R genotypes. The rs6014646 polymorphism was significantly associated with weight loss using co-dominant (p = 0.04 and dominant models (p = 0.03. These p-values were not statistically significant after strict control for multiple testing. Haplotype-based multivariate analysis using permutations showed that rs3827103-rs1543873 (p = 0.06, rs6014646-rs6024730 (p = 0.05 and rs3746619-rs3827103 (p = 0.10 displayed near-statistical significant results in relation to weight loss. No other significant associations or gene*diet interactions were detected for weight loss, fat mass loss, waist change and resting energy expenditure changes. CONCLUSION: The study

Association Between Coronary Artery Disease Genetic Variants and Subclinical Atherosclerosis: An Association Study and Meta-analysis.

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Zabalza, Michel; Subirana, Isaac; Lluis-Ganella, Carla; Sayols-Baixeras, Sergi; de Groot, Eric; Arnold, Roman; Cenarro, Ana; Ramos, Rafel; Marrugat, Jaume; Elosua, Roberto

2015-10-01

Recent studies have identified several genetic variants associated with coronary artery disease. Some of these genetic variants are not associated with classical cardiovascular risk factors and the mechanism of such associations is unclear. The aim of the study was to determine whether these genetic variants are related to subclinical atherosclerosis measured by carotid intima media thickness, carotid stiffness, and ankle brachial index. A cross-sectional study nested in the follow-up of the REGICOR cohort was undertaken. The study included 2667 individuals. Subclinical atherosclerosis measurements were performed with standardized methods. Nine genetic variants were genotyped to assess associations with subclinical atherosclerosis, individually and in a weighted genetic risk score. A systematic review and meta-analysis of previous studies that analyzed these associations was undertaken. Neither the selected genetic variants nor the genetic risk score were significantly associated with subclinical atherosclerosis. In the meta-analysis, the rs1746048 (CXCL12; n = 10581) risk allele was directly associated with carotid intima-media thickness (β = 0.008; 95% confidence interval, 0.001-0.015), whereas the rs6725887 (WDR12; n = 7801) risk allele was inversely associated with this thickness (β = -0.013; 95% confidence interval, -0.024 to -0.003). The analyzed genetic variants seem to mediate their association with coronary artery disease through different mechanisms. Our results generate the hypothesis that the CXCL12 variant appears to influence coronary artery disease risk through arterial remodeling and thickening, whereas the WDR12 risk variant could be related to higher plaque vulnerability. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Genetic polymorphisms of pharmacogenomic VIP variants in the Yi population from China.

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Yan, Mengdan; Li, Dianzhen; Zhao, Guige; Li, Jing; Niu, Fanglin; Li, Bin; Chen, Peng; Jin, Tianbo

2018-03-30

Drug response and target therapeutic dosage are different among individuals. The variability is largely genetically determined. With the development of pharmacogenetics and pharmacogenomics, widespread research have provided us a wealth of information on drug-related genetic polymorphisms, and the very important pharmacogenetic (VIP) variants have been identified for the major populations around the world whereas less is known regarding minorities in China, including the Yi ethnic group. Our research aims to screen the potential genetic variants in Yi population on pharmacogenomics and provide a theoretical basis for future medication guidance. In the present study, 80 VIP variants (selected from the PharmGKB database) were genotyped in 100 unrelated and healthy Yi adults recruited for our research. Through statistical analysis, we made a comparison between the Yi and other 11 populations listed in the HapMap database for significant SNPs detection. Two specific SNPs were subsequently enrolled in an observation on global allele distribution with the frequencies downloaded from ALlele FREquency Database. Moreover, F-statistics (Fst), genetic structure and phylogenetic tree analyses were conducted for determination of genetic similarity between the 12 ethnic groups. Using the χ2 tests, rs1128503 (ABCB1), rs7294 (VKORC1), rs9934438 (VKORC1), rs1540339 (VDR) and rs689466 (PTGS2) were identified as the significantly different loci for further analysis. The global allele distribution revealed that the allele "A" of rs1540339 and rs9934438 were more frequent in Yi people, which was consistent with the most populations in East Asia. F-statistics (Fst), genetic structure and phylogenetic tree analyses demonstrated that the Yi and CHD shared a closest relationship on their genetic backgrounds. Additionally, Yi was considered similar to the Han people from Shaanxi province among the domestic ethnic populations in China. Our results demonstrated significant differences on

Genetic risk variants in the CDKN2A/B, RTEL1 and EGFR genes are associated with somatic biomarkers in glioma.

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Ghasimi, Soma; Wibom, Carl; Dahlin, Anna M; Brännström, Thomas; Golovleva, Irina; Andersson, Ulrika; Melin, Beatrice

2016-05-01

During the last years, genome wide association studies have discovered common germline genetic variants associated with specific glioma subtypes. We aimed to study the association between these germline risk variants and tumor phenotypes, including copy number aberrations and protein expression. A total of 91 glioma patients were included. Thirteen well known genetic risk variants in TERT, EGFR, CCDC26, CDKN2A, CDKN2B, PHLDB1, TP53, and RTEL1 were selected for investigation of possible correlations with the glioma somatic markers: EGFR amplification, 1p/19q codeletion and protein expression of p53, Ki-67, and mutated IDH1. The CDKN2A/B risk variant, rs4977756, and the CDKN2B risk variant, rs1412829 were inversely associated (p = 0.049 and p = 0.002, respectively) with absence of a mutated IDH1, i.e., the majority of patients homozygous for the risk allele showed no or low expression of mutated IDH1. The RTEL1 risk variant, rs6010620 was associated (p = 0.013) with not having 1p/19q codeletion, i.e., the majority of patients homozygous for the risk allele did not show 1p/19q codeletion. In addition, the EGFR risk variant rs17172430 and the CDKN2B risk variant rs1412829, both showed a trend for association (p = 0.055 and p = 0.051, respectively) with increased EGFR copy number, i.e., the majority of patients homozygote for the risk alleles showed chromosomal gain or amplification of EGFR. Our findings indicate that CDKN2A/B risk genotypes are associated with primary glioblastoma without IDH mutation, and that there is an inverse association between RTEL1 risk genotypes and 1p/19q codeletion, suggesting that these genetic variants have a molecular impact on the genesis of high graded brain tumors. Further experimental studies are needed to delineate the functional mechanism of the association between genotype and somatic genetic aberrations.

Germline variants in MRE11/RAD50/NBN complex genes in childhood leukemia

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Mosor, Maria; Ziółkowska-Suchanek, Iwona; Nowicka, Karina; Dzikiewicz-Krawczyk, Agnieszka; Januszkiewicz–Lewandowska, Danuta; Nowak, Jerzy

2013-01-01

The MRE11, RAD50, and NBN genes encode proteins of the MRE11-RAD50-NBN (MRN) complex involved in cellular response to DNA damage and the maintenance of genome stability. In our previous study we showed that the germline p.I171V mutation in NBN may be considered as a risk factor in the development of childhood acute lymphoblastic leukemia (ALL) and some specific haplotypes of that gene may be associated with childhood leukemia. These findings raise important questions about the role of mutations in others genes of the MRN complex in childhood leukemia. The aim of this study was to answer the question whether MRE11 and RAD50 alterations may be associated with childhood ALL or AML. We estimated the frequency of constitutional mutations and polymorphisms in selected regions of MRE11, RAD50, and NBN in the group of 220 children diagnosed with childhood leukemias and controls (n=504/2200). The analysis was performed by specific amplification of region of interest by PCR and followed by multi-temperature single-strand conformation polymorphism (PCR-MSSCP) technique. We performed two molecular tests to examine any potential function of the detected the c.551+19G>A SNP in RAD50 gene. To our knowledge, this is the first analysis of the MRE11, RAD50 and NBN genes in childhood leukemia. The frequency of either the AA genotype or A allele of RAD50-rs17166050 were significantly different in controls compared to leukemia group (ALL+AML) (p<0.0019 and p<0.0019, respectively). The cDNA analysis of AA or GA genotypes carriers has not revealed evidence of splicing abnormality of RAD50 pre-mRNA. We measured the allelic-specific expression of G and A alleles at c.551+19G>A and the statistically significant overexpression of the G allele has been observed. Additionally we confirmed the higher incidence of the p.I171V mutation in the leukemia group (7/220) than among controls (12/2400) (p<0.0001). The formerly reported sequence variants in the RAD50 and MRE11 gene may not constitute a

A novel multiplex PCR-RFLP method for simultaneous detection of the MTHFR 677 C > T, eNOS +894 G > T and - eNOS -786 T > C variants among Malaysian Malays

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Loo Keat

2012-05-01

Full Text Available Abstract Background Hyperhomocysteinemia as a consequence of the MTHFR 677 C > T variant is associated with cardiovascular disease and stroke. Another factor that can potentially contribute to these disorders is a depleted nitric oxide level, which can be due to the presence of eNOS +894 G > T and eNOS −786 T > C variants that make an individual more susceptible to endothelial dysfunction. A number of genotyping methods have been developed to investigate these variants. However, simultaneous detection methods using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP analysis are still lacking. In this study, a novel multiplex PCR-RFLP method for the simultaneous detection of MTHFR 677 C > T and eNOS +894 G > T and eNOS −786 T > C variants was developed. A total of 114 healthy Malay subjects were recruited. The MTHFR 677 C > T and eNOS +894 G > T and eNOS −786 T > C variants were genotyped using the novel multiplex PCR-RFLP and confirmed by DNA sequencing as well as snpBLAST. Allele frequencies of MTHFR 677 C > T and eNOS +894 G > T and eNOS −786 T > C were calculated using the Hardy Weinberg equation. Methods The 114 healthy volunteers were recruited for this study, and their DNA was extracted. Primer pair was designed using Primer 3 Software version 0.4.0 and validated against the BLAST database. The primer specificity, functionality and annealing temperature were tested using uniplex PCR methods that were later combined into a single multiplex PCR. Restriction Fragment Length Polymorphism (RFLP was performed in three separate tubes followed by agarose gel electrophoresis. PCR product residual was purified and sent for DNA sequencing. Results The allele frequencies for MTHFR 677 C > T were 0.89 (C allele and 0.11 (T allele; for eNOS +894 G > T, the allele frequencies were 0.58 (G allele and 0.43 (T allele; and for eNOS −786 T > C, the allele

CFTR-France, a national relational patient database for sharing genetic and phenotypic data associated with rare CFTR variants.

Science.gov (United States)

Claustres, Mireille; Thèze, Corinne; des Georges, Marie; Baux, David; Girodon, Emmanuelle; Bienvenu, Thierry; Audrezet, Marie-Pierre; Dugueperoux, Ingrid; Férec, Claude; Lalau, Guy; Pagin, Adrien; Kitzis, Alain; Thoreau, Vincent; Gaston, Véronique; Bieth, Eric; Malinge, Marie-Claire; Reboul, Marie-Pierre; Fergelot, Patricia; Lemonnier, Lydie; Mekki, Chadia; Fanen, Pascale; Bergougnoux, Anne; Sasorith, Souphatta; Raynal, Caroline; Bareil, Corinne

2017-10-01

Most of the 2,000 variants identified in the CFTR (cystic fibrosis transmembrane regulator) gene are rare or private. Their interpretation is hampered by the lack of available data and resources, making patient care and genetic counseling challenging. We developed a patient-based database dedicated to the annotations of rare CFTR variants in the context of their cis- and trans-allelic combinations. Based on almost 30 years of experience of CFTR testing, CFTR-France (https://cftr.iurc.montp.inserm.fr/cftr) currently compiles 16,819 variant records from 4,615 individuals with cystic fibrosis (CF) or CFTR-RD (related disorders), fetuses with ultrasound bowel anomalies, newborns awaiting clinical diagnosis, and asymptomatic compound heterozygotes. For each of the 736 different variants reported in the database, patient characteristics and genetic information (other variations in cis or in trans) have been thoroughly checked by a dedicated curator. Combining updated clinical, epidemiological, in silico, or in vitro functional data helps to the interpretation of unclassified and the reassessment of misclassified variants. This comprehensive CFTR database is now an invaluable tool for diagnostic laboratories gathering information on rare variants, especially in the context of genetic counseling, prenatal and preimplantation genetic diagnosis. CFTR-France is thus highly complementary to the international database CFTR2 focused so far on the most common CF-causing alleles. © 2017 Wiley Periodicals, Inc.

Molecular basis for Duarte and Los Angeles variant galactosemia

Energy Technology Data Exchange (ETDEWEB)

Langley, S.D.; Lai, K.; Dembure, P.P. [Emory Univ. School of Medicine, Atlanta, GA (United States)] [and others

1997-02-01

Human erythrocytes that are homozygous for the Duarte enzyme variant of galactosemia (D/D) have a characteristic isoform on isoelectric focusing and 50% reduction in galactose-1-phosphate uridyltransferase (GALT) enzyme activity. The Duarte biochemical phenotype has a molecular genotype of N314D/N314D. The characteristic Duarte isoform is also associated with a variant called the {open_quotes}Los Angeles (LA) phenotype,{close_quotes} which has increased GALT enzyme activity. We evaluated GALT enzyme activity and screened the GALT genes of 145 patients with one or more N314D-containing alleles. We found seven with the LA biochemical phenotype, and all had a 1721C{r_arrow}T transition in exon 7 in cis with the N314D missense mutation. The 1721C{r_arrow}T transition is a neutral polymorphism for leucine at amino acid 218 (L218L). In pedigree analyses, this 1721C{r_arrow}T transition segregated with the LA phenotype of increased GALT activity in three different biochemical phenotypes (LA/N, LA/G, and LA/D). To determine the mechanism for increased activity of the LA variant, we compared GALT mRNA, protein abundance, and enzyme thermal stability in lymphoblast cell lines of D and LA phenotypes with comparable genotypes. GALT protein abundance was increased in LA compared to D alleles, but mRNA was similar among all genotypes. We conclude that the codon change N314D in cis with the base-pair transition 1721C{r_arrow}T produces the LA variant of galactosemia and that this nucleotide change increases GALT activity by increasing GALT protein abundance without increasing transcription or decreasing thermal lability. A favorable codon bias for the mutated codon with consequently increased translation rates is postulated as the mechanism. 23 refs., 3 figs., 4 tabs.

Comparison of 454 Ultra-Deep Sequencing and Allele-Specific Real-Time PCR with Regard to the Detection of Emerging Drug-Resistant Minor HIV-1 Variants after Antiretroviral Prophylaxis for Vertical Transmission.

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Andrea Hauser

Full Text Available Pregnant HIV-infected women were screened for the development of HIV-1 drug resistance after implementation of a triple-antiretroviral transmission prophylaxis as recommended by the WHO in 2006. The study offered the opportunity to compare amplicon-based 454 ultra-deep sequencing (UDS and allele-specific real-time PCR (ASPCR for the detection of drug-resistant minor variants in the HIV-1 reverse transcriptase (RT.Plasma samples from 34 Tanzanian women were previously analysed by ASPCR for key resistance mutations in the viral RT selected by AZT, 3TC, and NVP (K70R, K103N, Y181C, M184V, T215Y/F. In this study, the RT region of the same samples was investigated by amplicon-based UDS for resistance mutations using the 454 GS FLX System.Drug-resistant HIV-variants were identified in 69% (20/29 of women by UDS and in 45% (13/29 by ASPCR. The absolute number of resistance mutations identified by UDS was twice that identified by ASPCR (45 vs 24. By UDS 14 of 24 ASPCR-detected resistance mutations were identified at the same position. The overall concordance between UDS and ASPCR was 61.0% (25/41. The proportions of variants quantified by UDS were approximately 2-3 times lower than by ASPCR. Amplicon generation from samples with viral loads below 20,000 copies/ml failed more frequently by UDS compared to ASPCR (limit of detection = 650 copies/ml, resulting in missing or insufficient sequence coverage.Both methods can provide useful information about drug-resistant minor HIV-1 variants. ASPCR has a higher sensitivity than UDS, but is restricted to single resistance mutations. In contrast, UDS is limited by its requirement for high viral loads to achieve sufficient sequence coverage, but the sequence information reveals the complete resistance patterns within the genomic region analysed. Improvements to the UDS limit of detection are in progress, and UDS could then facilitate monitoring of drug-resistant minor variants in the HIV-1 quasispecies.

A trans-acting Variant within the Transcription Factor RIM101 Interacts with Genetic Background to Determine its Regulatory Capacity.

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Timothy Read

2016-01-01

Full Text Available Most genetic variants associated with disease occur within regulatory regions of the genome, underscoring the importance of defining the mechanisms underlying differences in regulation of gene expression between individuals. We discovered a pair of co-regulated, divergently oriented transcripts, AQY2 and ncFRE6, that are expressed in one strain of Saccharomyces cerevisiae, ∑1278b, but not in another, S288c. By combining classical genetics techniques with high-throughput sequencing, we identified a trans-acting single nucleotide polymorphism within the transcription factor RIM101 that causes the background-dependent expression of both transcripts. Subsequent RNA-seq experiments revealed that RIM101 regulates many more targets in S288c than in ∑1278b and that deletion of RIM101 in both backgrounds abrogates the majority of differential expression between the strains. Strikingly, only three transcripts undergo a significant change in expression after swapping RIM101 alleles between backgrounds, implying that the differences in the RIM101 allele lead to a remarkably focused transcriptional response. However, hundreds of RIM101-dependent targets undergo a subtle but consistent shift in expression in the S288c RIM101-swapped strain, but not its ∑1278b counterpart. We conclude that ∑1278b may harbor a variant(s that buffers against widespread transcriptional dysregulation upon introduction of a non-native RIM101 allele, emphasizing the importance of accounting for genetic background when assessing the impact of a regulatory variant.

Preferential binding to Elk-1 by SLE-associated IL10 risk allele upregulates IL10 expression.

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Daisuke Sakurai

Full Text Available Immunoregulatory cytokine interleukin-10 (IL-10 is elevated in sera from patients with systemic lupus erythematosus (SLE correlating with disease activity. The established association of IL10 with SLE and other autoimmune diseases led us to fine map causal variant(s and to explore underlying mechanisms. We assessed 19 tag SNPs, covering the IL10 gene cluster including IL19, IL20 and IL24, for association with SLE in 15,533 case and control subjects from four ancestries. The previously reported IL10 variant, rs3024505 located at 1 kb downstream of IL10, exhibited the strongest association signal and was confirmed for association with SLE in European American (EA (P = 2.7×10⁻⁸, OR = 1.30, but not in non-EA ancestries. SNP imputation conducted in EA dataset identified three additional SLE-associated SNPs tagged by rs3024505 (rs3122605, rs3024493 and rs3024495 located at 9.2 kb upstream, intron 3 and 4 of IL10, respectively, and SLE-risk alleles of these SNPs were dose-dependently associated with elevated levels of IL10 mRNA in PBMCs and circulating IL-10 protein in SLE patients and controls. Using nuclear extracts of peripheral blood cells from SLE patients for electrophoretic mobility shift assays, we identified specific binding of transcription factor Elk-1 to oligodeoxynucleotides containing the risk (G allele of rs3122605, suggesting rs3122605 as the most likely causal variant regulating IL10 expression. Elk-1 is known to be activated by phosphorylation and nuclear localization to induce transcription. Of interest, phosphorylated Elk-1 (p-Elk-1 detected only in nuclear extracts of SLE PBMCs appeared to increase with disease activity. Co-expression levels of p-Elk-1 and IL-10 were elevated in SLE T, B cells and monocytes, associated with increased disease activity in SLE B cells, and were best downregulated by ERK inhibitor. Taken together, our data suggest that preferential binding of activated Elk-1 to the IL10 rs3122605-G allele

PC-1 amino acid variant (K121Q) has no impact on progression of diabetic nephropathy in type 1 diabetic patients

DEFF Research Database (Denmark)

Jacobsen, Peter; Grarup, Niels; Tarnow, Lise

2002-01-01

Recently, an amino acid variant (K121Q) in the glycoprotein PC-1 (Q allele) has been associated with faster progression of diabetic nephropathy, as estimated by calculated creatinine clearance. We tested the impact of the PC-1 (K121Q) variant on loss of glomerular filtration rate (GFR) measured...

A Loss-of-Function Splice Acceptor Variant in IGF2 Is Protective for Type 2 Diabetes.

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Mercader, Josep M; Liao, Rachel G; Bell, Avery D; Dymek, Zachary; Estrada, Karol; Tukiainen, Taru; Huerta-Chagoya, Alicia; Moreno-Macías, Hortensia; Jablonski, Kathleen A; Hanson, Robert L; Walford, Geoffrey A; Moran, Ignasi; Chen, Ling; Agarwala, Vineeta; Ordoñez-Sánchez, María Luisa; Rodríguez-Guillen, Rosario; Rodríguez-Torres, Maribel; Segura-Kato, Yayoi; García-Ortiz, Humberto; Centeno-Cruz, Federico; Barajas-Olmos, Francisco; Caulkins, Lizz; Puppala, Sobha; Fontanillas, Pierre; Williams, Amy L; Bonàs-Guarch, Sílvia; Hartl, Chris; Ripke, Stephan; Tooley, Katherine; Lane, Jacqueline; Zerrweck, Carlos; Martínez-Hernández, Angélica; Córdova, Emilio J; Mendoza-Caamal, Elvia; Contreras-Cubas, Cecilia; González-Villalpando, María E; Cruz-Bautista, Ivette; Muñoz-Hernández, Liliana; Gómez-Velasco, Donaji; Alvirde, Ulises; Henderson, Brian E; Wilkens, Lynne R; Le Marchand, Loic; Arellano-Campos, Olimpia; Riba, Laura; Harden, Maegan; Gabriel, Stacey; Abboud, Hanna E; Cortes, Maria L; Revilla-Monsalve, Cristina; Islas-Andrade, Sergio; Soberon, Xavier; Curran, Joanne E; Jenkinson, Christopher P; DeFronzo, Ralph A; Lehman, Donna M; Hanis, Craig L; Bell, Graeme I; Boehnke, Michael; Blangero, John; Duggirala, Ravindranath; Saxena, Richa; MacArthur, Daniel; Ferrer, Jorge; McCarroll, Steven A; Torrents, David; Knowler, William C; Baier, Leslie J; Burtt, Noel; González-Villalpando, Clicerio; Haiman, Christopher A; Aguilar-Salinas, Carlos A; Tusié-Luna, Teresa; Flannick, Jason; Jacobs, Suzanne B R; Orozco, Lorena; Altshuler, David; Florez, Jose C

2017-11-01

Type 2 diabetes (T2D) affects more than 415 million people worldwide, and its costs to the health care system continue to rise. To identify common or rare genetic variation with potential therapeutic implications for T2D, we analyzed and replicated genome-wide protein coding variation in a total of 8,227 individuals with T2D and 12,966 individuals without T2D of Latino descent. We identified a novel genetic variant in the IGF2 gene associated with ∼20% reduced risk for T2D. This variant, which has an allele frequency of 17% in the Mexican population but is rare in Europe, prevents splicing between IGF2 exons 1 and 2. We show in vitro and in human liver and adipose tissue that the variant is associated with a specific, allele-dosage-dependent reduction in the expression of IGF2 isoform 2. In individuals who do not carry the protective allele, expression of IGF2 isoform 2 in adipose is positively correlated with both incidence of T2D and increased plasma glycated hemoglobin in individuals without T2D, providing support that the protective effects are mediated by reductions in IGF2 isoform 2. Broad phenotypic examination of carriers of the protective variant revealed no association with other disease states or impaired reproductive health. These findings suggest that reducing IGF2 isoform 2 expression in relevant tissues has potential as a new therapeutic strategy for T2D, even beyond the Latin American population, with no major adverse effects on health or reproduction. © 2017 by the American Diabetes Association.

MTHFR gene C677T and A1298C variants are associated with FMF risk in a Turkish cohort.

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Nursal, Ayse Feyda; Kaya, Süheyla; Sezer, Ozlem; Karakus, Nevin; Yigit, Serbulent

2018-02-01

Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme in homocysteine (Hcy) metabolism. We aimed to evaluate a possible relationship between MTHFR gene C677T (rs 1801133), A1298C (rs 1801131) variants and susceptibility to FMF in a Turkish cohort. This case-control study included 198 Turkish FMF patients and 100 healthy subjects as controls. MTHFR C677T and A1298C were analyzed by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) methods. The genotype distribution and allele frequency of the MTHFR C677T were statistically different between the patients and the control group (P=.006, P=.001, respectively). The frequency of the TT genotype and T allele of MTHFR C677T was significantly higher in the patients than in the controls. The genotype distribution of MTHFR A1298C variant did not show any statistically significant difference between the patients and the controls (P›.05). The patients had statistically different frequencies in allele C of MTHFR A1298C variant compared with the control (P=.032). We also examined the risk associated with inheriting the combined genotypes for the two MTHFR variants. According to these results, individuals who were CC homozygous at C677T locus and AA homozygous at A1298C locus have a lower risk of developing FMF (P=.002). Individuals who were TT homozygous at C677T locus and AC heterozygous at A1298C locus have higher risk of developing FMF (P=.033). Our findings clearly showed there was an association the MTHFR C677T/A1298C variants and susceptibility to FMF in the Turkish sample. © 2017 Wiley Periodicals, Inc.

The Mendelian inheritance of rare flesh and shell colour variants in the black-lipped pearl oyster (Pinctada margaritifera).

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Ky, Chin-Long; Nakasai, Seiji; Pommier, Steve; Sham Koua, Manaarii; Devaux, Dominique

2016-10-01

Pinctada margaritifera is French Polynesia's most economically important aquaculture species. This pearl oyster has the specific ability to produce cultured pearls with a very wide range of colours, depending on the colour phenotypes of donor oysters used. Its aquaculture is still based on natural spat collection from wild stocks. We investigated three rare colour variants of P. margaritifera - orange flesh, and red and white shell colour phenotypes - in comparison with the wild-type black flesh and shell commonly found in this species. The study aimed to assess the geographic distribution and genetic basis of these colour variants. Colour frequencies were evaluated during transfer and graft processes of pearl oyster seed captured at collector stations. Among the collection locations studied, Mangareva Island showed the highest rate of the orange flesh phenotype, whereas Takaroa and Takume atolls had relatively high rates of red and white shell phenotypes respectively. Broodstocks were made of these rare colour variants, and crosses were performed to produce first- and second-generation progenies to investigate segregation. The results were consistent with Mendelian ratios and suggest a distinct model with no co-dominance: (i) a two-allele model for flesh trait, whereby the orange allele is recessive to the black fleshed type, and (ii) a three-allele model for shell trait, whereby the black wild-type allele is dominant to the red coloration, which is dominant to the white shell. Furthermore, the proposed model provides the basis for producing selected donor pearl oyster lines through hatchery propagation. © 2016 Stichting International Foundation for Animal Genetics.

Identification of low-frequency variants associated with gout and serum uric acid levels

DEFF Research Database (Denmark)

Sulem, Patrick; Gudbjartsson, Daniel F; Walters, G Bragi

2011-01-01

We tested 16 million SNPs, identified through whole-genome sequencing of 457 Icelanders, for association with gout and serum uric acid levels. Genotypes were imputed into 41,675 chip-genotyped Icelanders and their relatives, for effective sample sizes of 968 individuals with gout and 15......,506 individuals for whom serum uric acid measurements were available. We identified a low-frequency missense variant (c.1580C>G) in ALDH16A1 associated with gout (OR = 3.12, P = 1.5 × 10(-16), at-risk allele frequency = 0.019) and serum uric acid levels (effect = 0.36 s.d., P = 4.5 × 10(-21)). We confirmed...... the association with gout by performing Sanger sequencing on 6,017 Icelanders. The association with gout was stronger in males relative to females. We also found a second variant on chromosome 1 associated with gout (OR = 1.92, P = 0.046, at-risk allele frequency = 0.986) and serum uric acid levels (effect = 0...

The Saccharomyces Genome Database Variant Viewer.

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Sheppard, Travis K; Hitz, Benjamin C; Engel, Stacia R; Song, Giltae; Balakrishnan, Rama; Binkley, Gail; Costanzo, Maria C; Dalusag, Kyla S; Demeter, Janos; Hellerstedt, Sage T; Karra, Kalpana; Nash, Robert S; Paskov, Kelley M; Skrzypek, Marek S; Weng, Shuai; Wong, Edith D; Cherry, J Michael

2016-01-04

The Saccharomyces Genome Database (SGD; http://www.yeastgenome.org) is the authoritative community resource for the Saccharomyces cerevisiae reference genome sequence and its annotation. In recent years, we have moved toward increased representation of sequence variation and allelic differences within S. cerevisiae. The publication of numerous additional genomes has motivated the creation of new tools for their annotation and analysis. Here we present the Variant Viewer: a dynamic open-source web application for the visualization of genomic and proteomic differences. Multiple sequence alignments have been constructed across high quality genome sequences from 11 different S. cerevisiae strains and stored in the SGD. The alignments and summaries are encoded in JSON and used to create a two-tiered dynamic view of the budding yeast pan-genome, available at http://www.yeastgenome.org/variant-viewer. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Genome-wide survey of allele-specific splicing in humans

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Scheffler Konrad

2008-06-01

data, including several examples for which there is experimental evidence of polymorphisms affecting splicing in the literature. We also present a set of novel allele-specific splicing candidates and discuss the strengths and weaknesses of alternative technologies for inferring the effect of sequence variants on mRNA splicing.

Delimiting Allelic Imbalance of TYMS by Allele-Specific Analysis.

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Balboa-Beltrán, Emilia; Cruz, Raquel; Carracedo, Angel; Barros, Francisco

2015-07-01

Allelic imbalance of thymidylate synthase (TYMS) is attributed to polymorphisms in the 5'- and 3'-untranslated region (UTR). These polymorphisms have been related to the risk of suffering different cancers, for example leukemia, breast or gastric cancer, and response to different drugs, among which are methotrexate glutamates, stavudine, and specifically 5-fluorouracil (5-FU), as TYMS is its direct target. A vast literature has been published in relation to 5-FU, even suggesting the sole use of these polymorphisms to effectively manage 5-FU dosage. Estimates of the extent to which these polymorphisms influence in TYMS expression have in the past been based on functional analysis by luciferase assays and quantification of TYMS mRNA, but both these studies, as the association studies with cancer risk or with toxicity or response to 5-FU, are very contradictory. Regarding functional assays, the artificial genetic environment created in luciferase assay and the problems derived from quantitative polymerase chain reactions (qPCRs), for example the use of a reference gene, may have distorted the results. To avoid these sources of interference, we have analyzed the allelic imbalance of TYMS by allelic-specific analysis in peripheral blood mononuclear cells (PBMCs) from patients.Allelic imbalance in PBMCs, taken from 40 patients with suspected myeloproliferative haematological diseases, was determined by fluorescent fragment analysis (for the 3'-UTR polymorphism), Sanger sequencing and allelic-specific qPCR in multiplex (for the 5'-UTR polymorphisms).For neither the 3'- nor the 5'-UTR polymorphisms did the observed allelic imbalance exceed 1.5 fold. None of the TYMS polymorphisms is statistically associated with allelic imbalance.The results acquired allow us to deny the previously established assertion of an influence of 2 to 4 fold of the rs45445694 and rs2853542 polymorphisms in the expression of TYMS and narrow its allelic imbalance to 1.5 fold, in our population

Null alleles and sequence variations at primer binding sites of STR loci within multiplex typing systems.

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Yao, Yining; Yang, Qinrui; Shao, Chengchen; Liu, Baonian; Zhou, Yuxiang; Xu, Hongmei; Zhou, Yueqin; Tang, Qiqun; Xie, Jianhui

2018-01-01

Rare variants are widely observed in human genome and sequence variations at primer binding sites might impair the process of PCR amplification resulting in dropouts of alleles, named as null alleles. In this study, 5 cases from routine paternity testing using PowerPlex ® 21 System for STR genotyping were considered to harbor null alleles at TH01, FGA, D5S818, D8S1179, and D16S539, respectively. The dropout of alleles was confirmed by using alternative commercial kits AGCU Expressmarker 22 PCR amplification kit and AmpFℓSTR ® . Identifiler ® Plus Kit, and sequencing results revealed a single base variation at the primer binding site of each STR locus. Results from the collection of previous reports show that null alleles at D5S818 were frequently observed in population detected by two PowerPlex ® typing systems and null alleles at D19S433 were mostly observed in Japanese population detected by two AmpFℓSTR™ typing systems. Furthermore, the most popular mutation type appeared the transition from C to T with G to A, which might have a potential relationship with DNA methylation. Altogether, these results can provide helpful information in forensic practice to the elimination of genotyping discrepancy and the development of primer sets. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of ABCB1 variants on neutrophil depression: a prospective study

DEFF Research Database (Denmark)

Bergmann, Troels Korshøj; Andersen, Charlotte Brasch; Gréen, Henrik

2010-01-01

toxicity was registered. Patients carrying one or two variant alleles of ABCB1 C3435T had progressively more pronounced neutrophil decrease at nadir (P-value 0.03). The same association was found for ABCB1 C1236T and G2677T/A with P-values of 0.06 and 0.02. No statistically significant correlations were...

The rs391957 variant cis-regulating oncogene GRP78 expression contributes to the risk of hepatocellular carcinoma.

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Zhu, Xiao; Zhang, Jinfang; Fan, Wenguo; Wang, Fang; Yao, Hong; Wang, Zifeng; Hou, Shengping; Tian, Yinghong; Fu, Weiming; Xie, Dan; Zhu, Wei; Long, Jun; Wu, Leijie; Zheng, Xuebao; Kung, Hsiangfu; Zhou, Keyuan; Lin, Marie C M; Luo, Hui; Li, Dongpei

2013-06-01

Glucose-regulated protein 78 (GRP78) is one of the most important responders to disease-related stress. We assessed the association of the promoter polymorphisms of GRP78 with risk of hepatocellular carcinoma (HCC) and GRP78 expression in a Chinese population. We examined 1007 patients undergoing diagnostic HCC and 810 unrelated healthy controls. Mechanisms by which the GRP78 promoter polymorphism modulates HCC risk and GRP78 levels were analyzed. The promoter haplotype and diplotype carrying rs391957 (-415bp) allele G and genotype GG was strongly associated with HCC risk. Luciferase reporter assays indicated that the promoter carrying rs391957 allele G (haplotype GCCd) showed increased activity in HepG2 cells and Hela cells. rs391957 was also shown to increase the affinity of the transcriptional activator Ets-2, the resistance to apoptosis, as well as cell instability in stressful microenvironment. Furthermore, compared with allele A, rs391957 allele G was associated with higher levels of GRP78 mRNA and protein in HCC tissues. These findings provided new insights into the pathogenesis of HCC and an unexpected effect of the interaction between rs391957 and Ets-2 on hepatocarcinogenesis, and especially supported the hypothesis that stress-related and evolutionarily conserved genetic variant(s) influencing transcriptional regulation could predict susceptibilities.

Assessment of polymorphic variants in the melanocortin-1 receptor gene with cutaneous pigmentation using an evolutionary approach.

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Kanetsky, Peter A; Ge, Fan; Najarian, Derek; Swoyer, Jennifer; Panossian, Saarene; Schuchter, Lynn; Holmes, Robin; Guerry, DuPont; Rebbeck, Timothy R

2004-05-01

The melanocortin-1 receptor gene (MC1R) encodes a membrane-bound receptor protein that is central to melanin synthesis. The coding region of MC1R is highly polymorphic and associations of variants with pigmentation phenotypes and risk for cutaneous neoplasms have been reported. We sought to determine the distribution and frequency of MC1R variants and their relationship to pigmentation characteristics in 179 Caucasian controls from the United States. One hundred thirty-five (75.4%) subjects carried one or more variants, and we determined that carriage of the previously designated "red hair color" (RHC) alleles, R151C, R160W, and D294H was strongly associated with fair pigmentation phenotypes including light hair and eye color, tendency to burn, decreased tendency to tan, and freckling. We used SIFT software to define MC1R protein positions that were predicted intolerant to amino acid substitutions; detected variants that corresponded to intolerant substitutions were D84E, R142H, R151C, I155T, R160W, and D294H. Carriage of one or more of these putative functionally important variants or the frameshift variant ins86A was significantly associated with fair pigmentation phenotypes. Analyses limited to carriage of ins86A and the three non-RHC alleles identified by SIFT were attenuated and no longer reached statistical significance. This is the first study to describe MC1R variants among control subjects from the U.S. Our results indicate that the frequency of variants is similar to that previously observed among non-U.S. Caucasians. Risk variants defined by either the published literature or by evolutionary criteria are strongly and significantly associated with all fair pigmentation phenotypes that were measured.

Sex-specific allelic transmission bias suggests sexual conflict at MC1R.

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Ducret, Valérie; Gaigher, Arnaud; Simon, Céline; Goudet, Jérôme; Roulin, Alexandre

2016-09-01

Sexual conflict arises when selection in one sex causes the displacement of the other sex from its phenotypic optimum, leading to an inevitable tension within the genome - called intralocus sexual conflict. Although the autosomal melanocortin-1-receptor gene (MC1R) can generate colour variation in sexually dichromatic species, most previous studies have not considered the possibility that MC1R may be subject to sexual conflict. In the barn owl (Tyto alba), the allele MC1RWHITE is associated with whitish plumage coloration, typical of males, and the allele MC1RRUFOUS is associated with dark rufous coloration, typical of females, although each sex can express any phenotype. Because each colour variant is adapted to specific environmental conditions, the allele MC1RWHITE may be more strongly selected in males and the allele MC1RRUFOUS in females. We therefore investigated whether MC1R genotypes are in excess or deficit in male and female fledglings compared with the expected Hardy-Weinberg proportions. Our results show an overall deficit of 7.5% in the proportion of heterozygotes in males and of 12.9% in females. In males, interannual variation in assortative pairing with respect to MC1R explained the year-specific deviations from Hardy-Weinberg proportions, whereas in females, the deficit was better explained by the interannual variation in the probability of inheriting the MC1RWHITE or MC1RRUFOUS allele. Additionally, we observed that sons inherit the MC1RRUFOUS allele from their fathers on average slightly less often than expected under the first Mendelian law. Transmission ratio distortion may be adaptive in this sexually dichromatic species if males and females are, respectively, selected to display white and rufous plumages. © 2016 John Wiley & Sons Ltd.

Analysis of IL12B Gene Variants in Inflammatory Bowel Disease

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Wagner, Johanna; Olszak, Torsten; Fries, Christoph; Tillack, Cornelia; Friedrich, Matthias; Beigel, Florian; Stallhofer, Johannes; Steib, Christian; Wetzke, Martin; Göke, Burkhard; Ochsenkühn, Thomas; Diegelmann, Julia; Czamara, Darina; Brand, Stephan

2012-01-01

Background IL12B encodes the p40 subunit of IL-12, which is also part of IL-23. Recent genome-wide association studies identified IL12B and IL23R as susceptibility genes for inflammatory bowel disease (IBD). However, the phenotypic effects and potential gene-gene interactions of IL12B variants are largely unknown. Methodology/Principal Findings We analyzed IL12B gene variants regarding association with Crohn's disease (CD) and ulcerative colitis (UC). Genomic DNA from 2196 individuals including 913 CD patients, 318 UC patients and 965 healthy, unrelated controls was analyzed for four SNPs in the IL12B gene region (rs3212227, rs17860508, rs10045431, rs6887695). Our analysis revealed an association of the IL12B SNP rs6887695 with susceptibility to IBD (p = 0.035; OR 1.15 [95% CI 1.01–1.31] including a trend for rs6887695 for association with CD (OR 1.41; [0.99–1.31], p = 0.066) and UC (OR 1.18 [0.97–1.43], p = 0.092). CD patients, who were homozygous C/C carriers of this SNP, had significantly more often non-stricturing, non-penetrating disease than carriers of the G allele (p = 6.8×10−5; OR = 2.84, 95% CI 1.66–4.84), while C/C homozygous UC patients had less often extensive colitis than G allele carriers (p = 0.029; OR = 0.36, 95% CI 0.14–0.92). In silico analysis predicted stronger binding of the minor C allele of rs6887695 to the transcription factor RORα which is involved in Th17 differentiation. Differences regarding the binding to the major and minor allele sequence of rs6887695 were also predicted for the transcription factors HSF1, HSF2, MZF1 and Oct-1. Epistasis analysis revealed weak epistasis of the IL12B SNP rs6887695 with several SNPs (rs11889341, rs7574865, rs7568275, rs8179673, rs10181656, rs7582694) in the STAT4 gene which encodes the major IL-12 downstream transcription factor STAT4 (p<0.05) but there was no epistasis between IL23R and IL12B variants. Conclusions/Significance The IL12B SNP rs6887695 modulates

Protein-altering variants associated with body mass index implicate pathways that control energy intake and expenditure in obesity

DEFF Research Database (Denmark)

Turcot, Valérie; Lu, Yingchang; Highland, Heather M

2018-01-01

,734 individuals to discover rare and low-frequency (minor allele frequency (MAF) obesity, 2 variants...... were in genes (MC4R and KSR2) previously observed to be mutated in extreme obesity and 2 variants were in GIPR. The effect sizes of rare variants are ~10 times larger than those of common variants, with the largest effect observed in carriers of an MC4R mutation introducing a stop codon (p.Tyr35Ter......, MAF = 0.01%), who weighed ~7 kg more than non-carriers. Pathway analyses based on the variants associated with BMI confirm enrichment of neuronal genes and provide new evidence for adipocyte and energy expenditure biology, widening the potential of genetically supported therapeutic targets in obesity....

HFE gene variants affect iron in the brain.

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Nandar, Wint; Connor, James R

2011-04-01

Iron accumulation in the brain and increased oxidative stress are consistent observations in many neurodegenerative diseases. Thus, we have begun examination into gene mutations or allelic variants that could be associated with loss of iron homeostasis. One of the mechanisms leading to iron overload is a mutation in the HFE gene, which is involved in iron metabolism. The 2 most common HFE gene variants are C282Y (1.9%) and H63D (8.9%). The C282Y HFE variant is more commonly associated with hereditary hemochromatosis, which is an autosomal recessive disorder, characterized by iron overload in a number of systemic organs. The H63D HFE variant appears less frequently associated with hemochromatosis, but its role in the neurodegenerative diseases has received more attention. At the cellular level, the HFE mutant protein resulting from the H63D HFE gene variant is associated with iron dyshomeostasis, increased oxidative stress, glutamate release, tau phosphorylation, and alteration in inflammatory response, each of which is under investigation as a contributing factor to neurodegenerative diseases. Therefore, the HFE gene variants are proposed to be genetic modifiers or a risk factor for neurodegenerative diseases by establishing an enabling milieu for pathogenic agents. This review will discuss the current knowledge of the association of the HFE gene variants with neurodegenerative diseases: amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, and ischemic stroke. Importantly, the data herein also begin to dispel the long-held view that the brain is protected from iron accumulation associated with the HFE mutations.

COMT Val158Met polymorphism, cognitive stability and cognitive flexibility: an experimental examination

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Rosa Elise C

2010-09-01

Full Text Available Abstract Background Dopamine in prefrontal cortex (PFC modulates core cognitive processes, notably working memory and executive control. Dopamine regulating genes and polymorphisms affecting PFC - including Catechol-O-Methyltransferase (COMT Val158Met - are crucial to understanding the molecular genetics of cognitive function and dysfunction. A mechanistic account of the COMT Val158Met effect associates the Met allele with increased tonic dopamine transmission underlying maintenance of relevant information, and the Val allele with increased phasic dopamine transmission underlying the flexibility of updating new information. Thus, consistent with some earlier work, we predicted that Val carriers would display poorer performance when the maintenance component was taxed, while Met carriers would be less efficient when rapid updating was required. Methods Using a Stroop task that manipulated level of required cognitive stability and flexibility, we examined reaction time performance of patients with schizophrenia (n = 67 and healthy controls (n = 186 genotyped for the Val/Met variation. Results In both groups we found a Met advantage for tasks requiring cognitive stability, but no COMT effect when a moderate level of cognitive flexibility was required, or when a conflict cost measure was calculated. Conclusions Our results do not support a simple stability/flexibility model of dopamine COMT Val/Met effects and suggest a somewhat different conceptualization and experimental operationalization of these cognitive components.

Polymorphic Variants rs3088442 and rs2292334 in the Organic Cation Transporter 3 (OCT3) Gene and Susceptibility Against Type 2 Diabetes: Role of their Interaction.

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Mahrooz, Abdolkarim; Alizadeh, Ahad; Hashemi-Soteh, Mohammad Bagher; Ghaffari-Cherati, Maryam; Hosseyni-Talei, Seyyedeh Raheleh

2017-02-01

In this study, we investigated whether two common variants (rs3088442G>A and rs2292334G>A) in the organic cation transporter 3 (OCT3) gene, a high-capacity transporter widely expressed in various tissues, affect susceptibility to type 2 diabetes (T2D) in patients newly diagnosed with T2D. We performed a study with 150 newly diagnosed patients with T2D and 152 controls. The genetic analyses were performed using the restricted fragment length polymorphism (RFLP) after PCR amplification. For the rs3088442G>A variant, A allele carriers had a significantly lower odds ratio (OR) vs. GG homozygotes in the BMI A variant was associated with a decreased risk of T2D (OR = 0.016, p A in the 3'-untranslated region of the OCT3 gene in susceptibility to T2D, and that the protective role is maintained in the presence of risky alleles of the variant rs2292334G>A. The association of the A allele of rs3088442G>A with T2D become weaker in obese people than that of non-obese. If confirmed in other populations, the rs3088442G>A variant as a genetic marker may potentially assist in the identification of individuals at an increased risk of T2D. Copyright © 2017 IMSS. Published by Elsevier Inc. All rights reserved.

A Genetic Biomarker of Oxidative Stress, the Paraoxonase-1 Q192R Gene Variant, Associates with Cardiomyopathy in CKD: A Longitudinal Study

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E. Dounousi

2016-01-01

Full Text Available Background. Oxidative stress is a hallmark of CKD and this alteration is strongly implicated in LV hypertrophy and in LV dysfunction. Methods and Patients. We resorted to the strongest genetic biomarker of paraoxonase-1 (PON1 activity, the Q192R variant in the PON1 gene, to unbiasedly assess (Mendelian randomization the cross-sectional and longitudinal association of this gene-variant with LV mass and function in 206 CKD patients with a 3-year follow-up. Results. The R allele of Q192R polymorphism associated with oxidative stress as assessed by plasma 8-isoPGF2α (P=0.03 and was dose-dependently related in a direct fashion to LVMI (QQ: 131.4 ± 42.6 g/m2; RQ: 147.7 ± 51.1 g/m2; RR: 167.3 ± 41.9 g/m2; P=0.001 and in an inverse fashion to systolic function (LV Ejection Fraction (QQ: 79 ± 12%; RQ: 69 ± 9%; RR: 65 ± 10% P=0.002. On longitudinal observation, this gene variant associated with the evolution of the same echocardiographic indicators [LVMI: 13.40 g/m2 per risk allele, P=0.005; LVEF: −2.96% per risk allele, P=0.001]. Multivariate analyses did not modify these associations. Conclusion. In CKD patients, the R allele of the Q192R variant in the PON1 gene is dose-dependently related to the severity of LVH and LV dysfunction and associates with the longitudinal evolution of these cardiac alterations. These results are compatible with the hypothesis that oxidative stress is implicated in cardiomyopathy in CKD patients.

Alzheimer's disease susceptibility variants in the MS4A6A gene are associated with altered levels of MS4A6A expression in blood.

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Proitsi, Petroula; Lee, Sang Hyuck; Lunnon, Katie; Keohane, Aoife; Powell, John; Troakes, Claire; Al-Sarraj, Safa; Furney, Simon; Soininen, Hilkka; Kłoszewska, Iwona; Mecocci, Patrizia; Tsolaki, Magda; Vellas, Bruno; Lovestone, Simon; Hodges, Angela

2014-02-01

An increased risk of developing Alzheimer's disease (AD) has previously been found to be associated with variants at the MS4A6A locus. We sought to identify which genes and transcripts in this region have altered expression in AD and mild cognitive impairment (MCI) and are influenced by the AD risk variant(s), as a first step to understanding the molecular basis of AD susceptibility at this locus. Common variants located within highly expressed MS4A6A transcripts were significantly associated with AD and MS4A6A expression levels in blood from MCI and AD subjects (p < 0.05, rs610932, rs7232, rs583791). More copies of the protective (minor) allele were associated with lower MS4A6A expression of each transcript (e.g., p = 0.019; rs610932-total MS4A6A). Furthermore, in heterozygous AD subjects, relative expression of the protective allele of V4-MS4A6A transcripts was lower (p < 0.008). Irrespective of genotype, MS4A6A transcripts were increased in blood from people with AD (p < 0.003), whereas lower expression of full length V1-MS4A6A (p = 0.002) and higher expression of V4-MS4A6A (p = 1.8 × 10(-4)) were observed in MCI, relative to elderly controls. The association between genotype and expression was less consistent in brain, although BA9 did have a similar genotype association with V4-MS4A6A transcripts as in blood. MS4A6A transcripts were widely expressed in tissues and cells, with the exception of V4-MS4A6A, which was not expressed in neuronal cells. Together these results suggest that high levels of MS4A6A in emerging AD pathology are detrimental. Persons with MCI may lower MS4A6A expression to minimize detrimental disease associated MS4A6A activity. However, those with the susceptibility allele appear unable to decrease expression sufficiently, which may explain their increased risk for developing AD. Inhibiting MS4A6A may therefore promote a more neuroprotective phenotype, although further work is needed to establish whether this is the case. Copyright © 2014

APOBEC3G Variants and Protection against HIV-1 Infection in Burkina Faso.

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Compaore, Tegwinde Rebeca; Soubeiga, Serge Theophile; Ouattara, Abdoul Karim; Obiri-Yeboah, Dorcas; Tchelougou, Damehan; Maiga, Mamoudou; Assih, Maleki; Bisseye, Cyrille; Bakouan, Didier; Compaore, Issaka Pierre; Dembele, Augustine; Martinson, Jeremy; Simpore, Jacques

2016-01-01

Studies on host factors, particularly the APOBEC3G gene, have previously found an association with AIDS progression in some populations and against some HIV-1 strains but not others. Our study had two main objectives: firstly, to screen a population from Burkina Faso for three variants of APOBEC3G previously described, and secondly to analyze the effect of these three variants and their haplotypes on HIV-1 infection with Circulating Recombinant Forms (CRFs) present in Burkina Faso. This case control study involved 708 seropositive and seronegative individuals. Genotyping was done by the TaqMan allelic discrimination method. Minor allele frequencies of rs6001417 (p<0.05), rs8177832 (P<0.05), and rs35228531 (P<0.001) were higher in seronegative subjects. The rs6001417 and rs8177832 SNPs were associated with HIV-1 infection in an additive model (P<0.01). Furthermore the SNP rs35228531 was also associated with HIV-1 infection in a dominant model (P<0.001). Odds ratio analysis of genotypes and alleles of the different APOBEC3G variants showed that there is a strong association between the minor genetic variants, genotype of the three SNPs, and HIV-1 status. Haplotype analysis demonstrated that rs6001417, rs8177832, and rs35228531 are in linkage disequilibrium. The haplotype GGT from the rs6001417, rs8177832 and rs35228531 respectively has a protective effect OR = 0.54 [0.43-0.68] with P<0.001. There was also associations between the haplotypes GGC OR = 1.6 [1.1;-2.3] P<0.05, and CGC OR = 5.21 [2.4-11.3] P<0.001, which increase the risk of infection by HIV-1 from almost two (2) to five (5) fold. This study demonstrates an association of rs6001417, rs8177832, and rs35228531 of APOBEC3G with HIV-1 infection in a population from Burkina Faso.

APOBEC3G Variants and Protection against HIV-1 Infection in Burkina Faso.

Directory of Open Access Journals (Sweden)

Tegwinde Rebeca Compaore

Full Text Available Studies on host factors, particularly the APOBEC3G gene, have previously found an association with AIDS progression in some populations and against some HIV-1 strains but not others. Our study had two main objectives: firstly, to screen a population from Burkina Faso for three variants of APOBEC3G previously described, and secondly to analyze the effect of these three variants and their haplotypes on HIV-1 infection with Circulating Recombinant Forms (CRFs present in Burkina Faso. This case control study involved 708 seropositive and seronegative individuals. Genotyping was done by the TaqMan allelic discrimination method. Minor allele frequencies of rs6001417 (p<0.05, rs8177832 (P<0.05, and rs35228531 (P<0.001 were higher in seronegative subjects. The rs6001417 and rs8177832 SNPs were associated with HIV-1 infection in an additive model (P<0.01. Furthermore the SNP rs35228531 was also associated with HIV-1 infection in a dominant model (P<0.001. Odds ratio analysis of genotypes and alleles of the different APOBEC3G variants showed that there is a strong association between the minor genetic variants, genotype of the three SNPs, and HIV-1 status. Haplotype analysis demonstrated that rs6001417, rs8177832, and rs35228531 are in linkage disequilibrium. The haplotype GGT from the rs6001417, rs8177832 and rs35228531 respectively has a protective effect OR = 0.54 [0.43-0.68] with P<0.001. There was also associations between the haplotypes GGC OR = 1.6 [1.1;-2.3] P<0.05, and CGC OR = 5.21 [2.4-11.3] P<0.001, which increase the risk of infection by HIV-1 from almost two (2 to five (5 fold. This study demonstrates an association of rs6001417, rs8177832, and rs35228531 of APOBEC3G with HIV-1 infection in a population from Burkina Faso.

RS 10767664 gene variant in Brain Derived Neurotrophic Factor (BDNF) affect metabolic changes and insulin resistance after a standard hypocaloric diet.

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de Luis, Daniel Antonio; Fernández Ovalle, H; Izaola, O; Primo, D; Aller, Rocío

2018-02-01

Role of BDNF variants on change in body weight and cardiovascular risk factors after weight loss remains unclear in obese patients. Our aim was to analyze the effects of rs10767664 BDNF gene polymorphism on body weight, cardiovascular risk factors and serum adipokine levels after a standard hypocaloric diet in obese subjects. A Caucasian population of 80 obese patients was analyzed before and after 3months on a standard hypocaloric diet. Fifty patients (62.5%) had the genotype AA and 30 (37.5%) subjects had the next genotypes; AT (25 patients, 31.3%) or TT (5 study subjects, 6.3%) (second group). In non T allele carriers, the decreases in weight-3.4±2.9kg (T allele group -1.7±2.0kg:p=0.01), BMI -1.5±0.2kg (T allele group -1.2±0.5kg:p=0.02), fat mass-2.3±1.1kg (T allele group -1.7±0.9kg:p=0.009), waist circumference-3.8±2.4cm (T allele group -2.1±3.1cm:p=0.008), triglycerides -13.2±7.5mg/dl (T allele group +2.8±1.2mg/dl:p=0.02), insulin -2.1±1.9mUI/L (T allele group -0.3±1.0mUI/L:p=0.01), HOMA-IR -0.9±0.4 (T allele group -0.1±0.8:p=0.01) and leptin -10.1±9.5ng/dl (T allele group -3.1±0.2ng/dl:p=0.01) were higher than T allele carriers. rs10767664 variant of BDNF gene modify anthropometric and biochemical changes after weight loss with a hypocaloric diet. Copyright © 2017 Elsevier Inc. All rights reserved.

ClinGen Pathogenicity Calculator: a configurable system for assessing pathogenicity of genetic variants.

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Patel, Ronak Y; Shah, Neethu; Jackson, Andrew R; Ghosh, Rajarshi; Pawliczek, Piotr; Paithankar, Sameer; Baker, Aaron; Riehle, Kevin; Chen, Hailin; Milosavljevic, Sofia; Bizon, Chris; Rynearson, Shawn; Nelson, Tristan; Jarvik, Gail P; Rehm, Heidi L; Harrison, Steven M; Azzariti, Danielle; Powell, Bradford; Babb, Larry; Plon, Sharon E; Milosavljevic, Aleksandar

2017-01-12

The success of the clinical use of sequencing based tests (from single gene to genomes) depends on the accuracy and consistency of variant interpretation. Aiming to improve the interpretation process through practice guidelines, the American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP) have published standards and guidelines for the interpretation of sequence variants. However, manual application of the guidelines is tedious and prone to human error. Web-based tools and software systems may not only address this problem but also document reasoning and supporting evidence, thus enabling transparency of evidence-based reasoning and resolution of discordant interpretations. In this report, we describe the design, implementation, and initial testing of the Clinical Genome Resource (ClinGen) Pathogenicity Calculator, a configurable system and web service for the assessment of pathogenicity of Mendelian germline sequence variants. The system allows users to enter the applicable ACMG/AMP-style evidence tags for a specific allele with links to supporting data for each tag and generate guideline-based pathogenicity assessment for the allele. Through automation and comprehensive documentation of evidence codes, the system facilitates more accurate application of the ACMG/AMP guidelines, improves standardization in variant classification, and facilitates collaborative resolution of discordances. The rules of reasoning are configurable with gene-specific or disease-specific guideline variations (e.g. cardiomyopathy-specific frequency thresholds and functional assays). The software is modular, equipped with robust application program interfaces (APIs), and available under a free open source license and as a cloud-hosted web service, thus facilitating both stand-alone use and integration with existing variant curation and interpretation systems. The Pathogenicity Calculator is accessible at http

Type 2 diabetes-related variants influence the risk of developing multiple myeloma

DEFF Research Database (Denmark)

Ríos, Rafael; Lupiañez, Carmen Belén; Campa, Daniele

2015-01-01

Type 2 diabetes (T2D) has been suggested to be a risk factor for multiple myeloma (MM), but the relationship between the two traits is still not well understood. The aims of this study were to evaluate whether 58 genome-wide-association-studies (GWAS)-identified common variants for T2D influence...... genetic information (area under the curve (AUC)=0.645 vs AUC=0.629; P=4.05×10(-) (06)). A gender-stratified analysis also revealed a significant gender effect modification for ADAM30rs2641348 and NOTCH2rs10923931 variants (Pinteraction=0.001 and 0.0004, respectively). Men carrying the ADAM30rs2641348C...... carrying the KCNQ1rs2237892T allele or the CDKN2A-2Brs2383208G/G, IGF1rs35767T/T and MADDrs7944584T/T genotypes had a significantly increased risk of MM (odds ratio (OR)=1.32-2.13) whereas those carrying the KCNJ11rs5215C, KCNJ11rs5219T and THADArs7578597C alleles or the FTOrs8050136A/A and LTArs1041981C...

The quest for rare variants: pooled multiplexed next generation sequencing in plants.

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Marroni, Fabio; Pinosio, Sara; Morgante, Michele

2012-01-01

Next generation sequencing (NGS) instruments produce an unprecedented amount of sequence data at contained costs. This gives researchers the possibility of designing studies with adequate power to identify rare variants at a fraction of the economic and labor resources required by individual Sanger sequencing. As of today, few research groups working in plant sciences have exploited this potentiality, showing that pooled NGS provides results in excellent agreement with those obtained by individual Sanger sequencing. The aim of this review is to convey to the reader the general ideas underlying the use of pooled NGS for the identification of rare variants. To facilitate a thorough understanding of the possibilities of the method, we will explain in detail the possible experimental and analytical approaches and discuss their advantages and disadvantages. We will show that information on allele frequency obtained by pooled NGS can be used to accurately compute basic population genetics indexes such as allele frequency, nucleotide diversity, and Tajima's D. Finally, we will discuss applications and future perspectives of the multiplexed NGS approach.

The Quest for Rare Variants: Pooled Multiplexed Next Generation Sequencing in Plants

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Fabio eMarroni

2012-06-01

Full Text Available Next generation sequencing (NGS instruments produce an unprecedented amount of sequence data at contained costs. This gives researchers the possibility of designing studies with adequate power to identify rare variants at a fraction of the economic and labor resources required by individual Sanger sequencing. As of today, only three research groups working in plant sciences have exploited this potentiality. They showed that pooled NGS can provide results in excellent agreement with those obtained by individual Sanger sequencing. Aim of this review is to convey to the reader the general ideas underlying the use of pooled NGS for the identification of rare variants. To facilitate a thorough understanding of the possibilities of the method we will explain in detail the variations in study design and discuss their advantages and disadvantages. We will show that information on allele frequency obtained by pooled next generation sequencing can be used to accurately compute basic population genetics indexes such as allele frequency, nucleotide diversity and Tajima’s D. Finally we will discuss applications and future perspectives of the multiplexed NGS approach.

The IL23R R381Q gene variant protects against immune-mediated diseases by impairing IL-23-induced Th17 effector response in humans.

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Paola Di Meglio

2011-02-01

Full Text Available IL-23 and Th17 cells are key players in tissue immunosurveillance and are implicated in human immune-mediated diseases. Genome-wide association studies have shown that the IL23R R381Q gene variant protects against psoriasis, Crohn's disease and ankylosing spondylitis. We investigated the immunological consequences of the protective IL23R R381Q gene variant in healthy donors. The IL23R R381Q gene variant had no major effect on Th17 cell differentiation as the frequency of circulating Th17 cells was similar in carriers of the IL23R protective (A and common (G allele. Accordingly, Th17 cells generated from A and G donors produced similar amounts of Th17 cytokines. However, IL-23-mediated Th17 cell effector function was impaired, as Th17 cells from A allele carriers had significantly reduced IL-23-induced IL-17A production and STAT3 phosphorylation compared to G allele carriers. Our functional analysis of a human disease-associated gene variant demonstrates that IL23R R381Q exerts its protective effects through selective attenuation of IL-23-induced Th17 cell effector function without interfering with Th17 differentiation, and highlights its importance in the protection against IL-23-induced tissue pathologies.

The IL23R R381Q gene variant protects against immune-mediated diseases by impairing IL-23-induced Th17 effector response in humans.

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Di Meglio, Paola; Di Cesare, Antonella; Laggner, Ute; Chu, Chung-Ching; Napolitano, Luca; Villanova, Federica; Tosi, Isabella; Capon, Francesca; Trembath, Richard C; Peris, Ketty; Nestle, Frank O

2011-02-22

IL-23 and Th17 cells are key players in tissue immunosurveillance and are implicated in human immune-mediated diseases. Genome-wide association studies have shown that the IL23R R381Q gene variant protects against psoriasis, Crohn's disease and ankylosing spondylitis. We investigated the immunological consequences of the protective IL23R R381Q gene variant in healthy donors. The IL23R R381Q gene variant had no major effect on Th17 cell differentiation as the frequency of circulating Th17 cells was similar in carriers of the IL23R protective (A) and common (G) allele. Accordingly, Th17 cells generated from A and G donors produced similar amounts of Th17 cytokines. However, IL-23-mediated Th17 cell effector function was impaired, as Th17 cells from A allele carriers had significantly reduced IL-23-induced IL-17A production and STAT3 phosphorylation compared to G allele carriers. Our functional analysis of a human disease-associated gene variant demonstrates that IL23R R381Q exerts its protective effects through selective attenuation of IL-23-induced Th17 cell effector function without interfering with Th17 differentiation, and highlights its importance in the protection against IL-23-induced tissue pathologies.

Can cognitive assessment really discriminate early stages of Alzheimer's and behavioural variant frontotemporal dementia at initial clinical presentation?

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Reul, Sophia; Lohmann, Hubertus; Wiendl, Heinz; Duning, Thomas; Johnen, Andreas

2017-08-09

Neuropsychological testing is considered crucial for differential diagnosis of Alzheimer's disease (AD) and behavioural variant frontotemporal dementia (bvFTD). In-depth neuropsychological assessment revealed specific dysfunctions in the two dementia syndromes. However, a significant overlap of cognitive impairments exists in early disease stages. We questioned whether a standard neuropsychological assessment at initial clinical presentation can delineate patients with AD versus bvFTD. In a retrospective approach, we evaluated and compared how cognitive profiles assessed at initial clinical presentation predicted the diagnosis of later verified AD (n = 43) and bvFTD (n = 26). Additionally, the neuropsychological standard domains memory, language, visuospatial skills, executive functions, praxis and social cognition were subjected to stepwise discriminant analysis to compare their differential contribution to diagnosis. Regardless of diagnosis, a percentage of patients presented with major deterioration in a wide range of cognitive domains when compared with age-matched normative data. Only few significant differences were detected on the group level: Patients with AD were relatively more impaired in the verbal recall, verbal recognition, figure copy, and surprisingly in the executive subdomains, set shifting and processing speed whereas bvFTD was characterised by more deficits in imitation of face postures. A combination of tests for verbal recall, imitation of limb and face postures, and figure copy showed the greatest discriminatory power. Our results imply that the contribution of a standard neuropsychological assessment is limited for differential diagnosis of AD and bvFTD at initial presentation. In contrast to current clinical guidelines, executive functions are neither particularly nor exclusively impaired in patients with bvFTD when assessed within a standard clinical neuropsychological test battery. The significant overlap of bvFTD and AD

The Arg59Trp variant in ANGPTL8 (betatrophin) is associated with total and HDL-cholesterol in American Indians and Mexican Americans and differentially affects cleavage of ANGPTL3.

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Hanson, Robert L; Leti, Fatjon; Tsinajinnie, Darwin; Kobes, Sayuko; Puppala, Sobha; Curran, Joanne E; Almasy, Laura; Lehman, Donna M; Blangero, John; Duggirala, Ravindranath; DiStefano, Johanna K

2016-06-01

We previously identified a locus linked to total cholesterol (TC) concentration in Pima Indians on chromosome 19p. To characterize this locus, we genotyped >2000 SNPs in 1838 Pimas and assessed association with log(TC). We observed evidence for association with log(TC) with rs2278426 (3.5% decrease/copy of the T allele; P=5.045×10(-6)) in the ANGPTL8 (angiopoietin-like 8) gene. We replicated this association in 2413 participants of the San Antonio Mexican American Family Study (SAMAFS: 2.0% decrease per copy of the T allele; P=0.005842). In a meta-analysis of the combined data, we found the strongest estimated effect with rs2278426 (P=2.563×10(-7)). The variant T allele at rs2278426 predicts an Arg59Trp substitution and has previously been associated with LDL-C and HDL-C. In Pimas and SAMAFS participants, the T allele of rs2278426 was associated with reduced HDL-C levels (P=0.000741 and 0.00002, respectively), and the combined estimated effect for the two cohorts was -3.8% (P=8.526×10(-8)). ANGPTL8 transcript and protein levels increased in response to both glucose and insulin. The variant allele was associated with increased levels of cleaved ANGPTL3. We conclude that individuals with the variant allele may have lower TC and HDL-C levels due to increased activation of ANGPTL3 by ANGPTL8. Copyright © 2016 Elsevier Inc. All rights reserved.

Genetic variants in IL-6/JAK/STAT3 pathway and the risk of CRC.

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Wang, Shuwei; Zhang, Weidong

2016-05-01

Interleukin (IL)-6 and the downstream Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway have previously been reported to be important in the development of colorectal cancer (CRC), and several studies have shown the relationship between the polymorphisms of related genes in this pathway with the risk of CRC. However, the findings of these related studies are inconsistent. Moreover, there has no systematic review and meta-analysis to evaluate the relationship between genetic variants in IL-6/JAK/STAT3 pathway and CRC susceptibility. Hence, we conducted a meta-analysis to explore the relationship between polymorphisms in IL-6/JAK/STAT3 pathway genes and CRC risk. Eighteen eligible studies with a total of 13,795 CRC cases and 18,043 controls were identified by searching PubMed, Web of Science, Embase, and the Cochrane Library databases for the period up to September 15, 2015. Odds ratios (ORs) and their 95 % confidence intervals (CIs) were used to calculate the strength of the association. Our results indicated that IL-6 genetic variants in allele additive model (OR = 1.05, 95 % CI = 1.00, 1.09) and JAK2 genetic variants (OR = 1.40, 95 % CI = 1.15, 1.65) in genotype recessive model were significantly associated with CRC risk. Moreover, the pooled data revealed that IL-6 rs1800795 polymorphism significantly increased the risk of CRC in allele additive model in Europe (OR = 1.07, 95 % CI = 1.01, 1.14). In conclusion, the present findings indicate that IL-6 and JAK2 genetic variants are associated with the increased risk of CRC while STAT3 genetic variants not. We need more well-designed clinical studies covering more countries and population to definitively establish the association between genetic variants in IL-6/JAK/STAT3 pathway and CRC susceptibility.

Rare Coding Variants in ANGPTL6 Are Associated with Familial Forms of Intracranial Aneurysm.

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Bourcier, Romain; Le Scouarnec, Solena; Bonnaud, Stéphanie; Karakachoff, Matilde; Bourcereau, Emmanuelle; Heurtebise-Chrétien, Sandrine; Menguy, Céline; Dina, Christian; Simonet, Floriane; Moles, Alexis; Lenoble, Cédric; Lindenbaum, Pierre; Chatel, Stéphanie; Isidor, Bertrand; Génin, Emmanuelle; Deleuze, Jean-François; Schott, Jean-Jacques; Le Marec, Hervé; Loirand, Gervaise; Desal, Hubert; Redon, Richard

2018-01-04

Intracranial aneurysms (IAs) are acquired cerebrovascular abnormalities characterized by localized dilation and wall thinning in intracranial arteries, possibly leading to subarachnoid hemorrhage and severe outcome in case of rupture. Here, we identified one rare nonsense variant (c.1378A>T) in the last exon of ANGPTL6 (Angiopoietin-Like 6)-which encodes a circulating pro-angiogenic factor mainly secreted from the liver-shared by the four tested affected members of a large pedigree with multiple IA-affected case subjects. We showed a 50% reduction of ANGPTL6 serum concentration in individuals heterozygous for the c.1378A>T allele (p.Lys460Ter) compared to relatives homozygous for the normal allele, probably due to the non-secretion of the truncated protein produced by the c.1378A>T transcripts. Sequencing ANGPTL6 in a series of 94 additional index case subjects with familial IA identified three other rare coding variants in five case subjects. Overall, we detected a significant enrichment (p = 0.023) in rare coding variants within this gene among the 95 index case subjects with familial IA, compared to a reference population of 404 individuals with French ancestry. Among the 6 recruited families, 12 out of 13 (92%) individuals carrying IA also carry such variants in ANGPTL6, versus 15 out of 41 (37%) unaffected ones. We observed a higher rate of individuals with a history of high blood pressure among affected versus healthy individuals carrying ANGPTL6 variants, suggesting that ANGPTL6 could trigger cerebrovascular lesions when combined with other risk factors such as hypertension. Altogether, our results indicate that rare coding variants in ANGPTL6 are causally related to familial forms of IA. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

A role for coding functional variants in HNF4A in type 2 diabetes susceptibility

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Jafar-Mohammadi, B; Groves, C J; Gjesing, A P

2011-01-01

Rare mutations in the gene HNF4A, encoding the transcription factor hepatocyte nuclear factor 4α (HNF-4A), account for ~5% of cases of MODY and more frequent variants in this gene may be involved in multifactorial forms of diabetes. Two low-frequency, non-synonymous variants in HNF4A (V255M, minor...... allele frequency [MAF] ~0.1%; T130I, MAF ~3.0%)-known to influence downstream HNF-4A target gene expression-are of interest, but previous type 2 diabetes association reports were inconclusive. We aimed to evaluate the contribution of these variants to type 2 diabetes susceptibility through large...

Evidence for more than one Parkinson's disease-associated variant within the HLA region.

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Erin M Hill-Burns

Full Text Available Parkinson's disease (PD was recently found to be associated with HLA in a genome-wide association study (GWAS. Follow-up GWAS's replicated the PD-HLA association but their top hits differ. Do the different hits tag the same locus or is there more than one PD-associated variant within HLA? We show that the top GWAS hits are not correlated with each other (0.00≤r(2≤0.15. Using our GWAS (2000 cases, 1986 controls we conducted step-wise conditional analysis on 107 SNPs with P<10(-3 for PD-association; 103 dropped-out, four remained significant. Each SNP, when conditioned on the other three, yielded P(SNP1 = 5×10(-4, P(SNP2 = 5×10(-4, P(SNP3 = 4×10(-3 and P(SNP4 = 0.025. The four SNPs were not correlated (0.01≤r(2≤0.20. Haplotype analysis (excluding rare SNP2 revealed increasing PD risk with increasing risk alleles from OR = 1.27, P = 5×10(-3 for one risk allele to OR = 1.65, P = 4×10(-8 for three. Using additional 843 cases and 856 controls we replicated the independent effects of SNP1 (P(conditioned-on-SNP4 = 0.04 and SNP4 (P(conditioned-on-SNP1 = 0.04; SNP2 and SNP3 could not be replicated. In pooled GWAS and replication, SNP1 had OR(conditioned-on-SNP4 = 1.23, P(conditioned-on-SNP4 = 6×10(-7; SNP4 had OR(conditioned-on-SNP1 = 1.18, P(conditioned-on-SNP1 = 3×10(-3; and the haplotype with both risk alleles had OR = 1.48, P = 2×10(-12. Genotypic OR increased with the number of risk alleles an individual possessed up to OR = 1.94, P = 2×10(-11 for individuals who were homozygous for the risk allele at both SNP1 and SNP4. SNP1 is a variant in HLA-DRA and is associated with HLA-DRA, DRB5 and DQA2 gene expression. SNP4 is correlated (r(2 = 0.95 with variants that are associated with HLA-DQA2 expression, and with the top HLA SNP from the IPDGC GWAS (r(2 = 0.60. Our findings suggest more than one PD-HLA association; either different alleles of the same gene

Biallelic Variants in UBA5 Link Dysfunctional UFM1 Ubiquitin-like Modifier Pathway to Severe Infantile-Onset Encephalopathy.

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Muona, Mikko; Ishimura, Ryosuke; Laari, Anni; Ichimura, Yoshinobu; Linnankivi, Tarja; Keski-Filppula, Riikka; Herva, Riitta; Rantala, Heikki; Paetau, Anders; Pöyhönen, Minna; Obata, Miki; Uemura, Takefumi; Karhu, Thomas; Bizen, Norihisa; Takebayashi, Hirohide; McKee, Shane; Parker, Michael J; Akawi, Nadia; McRae, Jeremy; Hurles, Matthew E; Kuismin, Outi; Kurki, Mitja I; Anttonen, Anna-Kaisa; Tanaka, Keiji; Palotie, Aarno; Waguri, Satoshi; Lehesjoki, Anna-Elina; Komatsu, Masaaki

2016-09-01

The ubiquitin fold modifier 1 (UFM1) cascade is a recently identified evolutionarily conserved ubiquitin-like modification system whose function and link to human disease have remained largely uncharacterized. By using exome sequencing in Finnish individuals with severe epileptic syndromes, we identified pathogenic compound heterozygous variants in UBA5, encoding an activating enzyme for UFM1, in two unrelated families. Two additional individuals with biallelic UBA5 variants were identified from the UK-based Deciphering Developmental Disorders study and one from the Northern Finland Intellectual Disability cohort. The affected individuals (n = 9) presented in early infancy with severe irritability, followed by dystonia and stagnation of development. Furthermore, the majority of individuals display postnatal microcephaly and epilepsy and develop spasticity. The affected individuals were compound heterozygous for a missense substitution, c.1111G>A (p.Ala371Thr; allele frequency of 0.28% in Europeans), and a nonsense variant or c.164G>A that encodes an amino acid substitution p.Arg55His, but also affects splicing by facilitating exon 2 skipping, thus also being in effect a loss-of-function allele. Using an in vitro thioester formation assay and cellular analyses, we show that the p.Ala371Thr variant is hypomorphic with attenuated ability to transfer the activated UFM1 to UFC1. Finally, we show that the CNS-specific knockout of Ufm1 in mice causes neonatal death accompanied by microcephaly and apoptosis in specific neurons, further suggesting that the UFM1 system is essential for CNS development and function. Taken together, our data imply that the combination of a hypomorphic p.Ala371Thr variant in trans with a loss-of-function allele in UBA5 underlies a severe infantile-onset encephalopathy. Copyright © 2016 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Analysis of 60 706 Exomes Questions the Role of De Novo Variants Previously Implicated in Cardiac Disease

DEFF Research Database (Denmark)

Paludan-Müller, Christian; Ahlberg, Gustav; Ghouse, Jonas

2017-01-01

BACKGROUND: De novo variants in the exome occur at a rate of 1 per individual per generation, and because of the low reproductive fitness for de novo variants causing severe disease, the likelihood of finding these as standing variations in the general population is low. Therefore, this study...... sought to evaluate the pathogenicity of de novo variants previously associated with cardiac disease based on a large population-representative exome database. METHODS AND RESULTS: We performed a literature search for previous publications on de novo variants associated with severe arrhythmias...... trio studies (>1000 subjects). Of the monogenic variants, 11% (23/211) were present in ExAC, whereas 26% (802/3050) variants believed to increase susceptibility of disease were identified in ExAC. Monogenic de novo variants in ExAC had a total allele count of 109 and with ≈844 expected cases in Ex...

The IL23R A/Gln381 allele promotes IL-23 unresponsiveness in human memory T-helper 17 cells and impairs Th17 responses in psoriasis patients.

Science.gov (United States)

Di Meglio, Paola; Villanova, Federica; Napolitano, Luca; Tosi, Isabella; Terranova Barberio, Manuela; Mak, Rose K; Nutland, Sarah; Smith, Catherine H; Barker, Jonathan N W N; Todd, John A; Nestle, Frank O

2013-10-01

We and others have shown that the minor, nonconserved allele Gln381 of the Arg381Gln single-nucleotide polymorphism (rs11209026G>A) of the IL-23 receptor gene (IL23R) protects against psoriasis. Moreover, we have recently shown impaired IL-23-induced IL-17A production and STAT-3 phosphorylation in Th17 cells generated in vitro from healthy individuals heterozygous for the protective A allele (GA). However, the biological effect of this variant has not been determined in homozygous carriers of the protective A allele (AA), nor in psoriatic patients. Here we expand our functional investigation of the IL23R Arg381Gln gene variant to include AA homozygous individuals. By using isolated memory CD4+ T cells, we found attenuated IL-23-induced Th17 response in heterozygous individuals. Moreover, we found that AA homozygous individuals were strikingly unresponsive to IL-23, with minimal or no IL-17A and IL-17F production and failure of human memory Th17 cell survival/expansion. Finally, IL-23-induced Th17 response was also attenuated in age- and sex-matched GA versus GG psoriatic patients undergoing systemic treatment. Taken together, our data provide evidence for an allele-dosage effect for IL-23R Gln381 and indicate that common gene alleles associated with complex diseases might have biological effects of considerable magnitude in homozygous carriers.

Assessment of the myostatin Q204X allele using an allelic discrimination assay

OpenAIRE

Sifuentes-Rincón,Ana M.; Puentes-Montiel,Herlinda E.; Moreno-Medina,Víctor R.; Rosa-Reyna,Xóchitl F. de la

2006-01-01

An allelic discrimination assay was designed and used to determine the genotypic and allelic frequencies of the myostatin (MSTN) gene Q204X allele from two Mexican Full-French herds. The assay is a simple high throughput genotyping method that could be applied to investigate the effect of the Q204X allele on the Charolais breed.

Functional consequences of the macrophage stimulating protein 689C inflammatory bowel disease risk allele.

Directory of Open Access Journals (Sweden)

Steven E Kauder

Full Text Available Macrophage stimulating protein (MSP is a serum growth factor that binds to and activates the receptor tyrosine kinase, Recepteur d'Origine Nantais (RON. A non-synonymous coding variant in MSP (689C has been associated with genetic susceptibility to both Crohn's disease and ulcerative colitis, two major types of inflammatory bowel disease (IBD characterized by chronic inflammation of the digestive tract. We investigated the consequences of this polymorphism for MSP-RON pathway activity and IBD pathogenesis.RON expression patterns were examined on mouse and human cells and tissues under normal and disease conditions to identify cell types regulated by MSP-RON. Recombinant MSP variants were tested for their ability to bind and stimulate RON and undergo proteolytic activation. MSP concentrations were quantified in the serum of individuals carrying the MSP 689R and 689C alleles.In intestinal tissue, RON was primarily expressed by epithelial cells under normal and disease conditions. The 689C polymorphism had no impact on the ability of MSP to bind to or signal through RON. In a cohort of normal individuals and IBD patients, carriers of the 689C polymorphism had lower concentrations of MSP in their serum.By reducing the quantities of circulating MSP, the 689C polymorphism, or a variant in linkage disequilibrium with this polymorphism, may impact RON ligand availability and thus receptor activity. Given the known functions of RON in regulating wound healing and our analysis of RON expression patterns in human intestinal tissue, these data suggest that decreased RON activity may impact the efficiency of epithelial repair and thus underlie the increased IBD susceptibility associated with the MSP 689C allele.

Sociolinguistic variables and cognition.

Science.gov (United States)

Thomas, Erik R

2011-11-01

Sociolinguistics has examined mental organization of language only sporadically. Meanwhile, areas of linguistics that deal with cognitive organization seldom delve deeply into language variation. Variation is essential for understanding how language is structured cognitively, however. Three kinds of evidence are discussed to illustrate this point. First, style shifting demonstrates that language users develop detailed associations of when to produce specific linguistic forms, depending on the pragmatic context. Second, variation in fine-grained phonetic cues shows that cognitive organization applies to linguistic forms not otherwise known to be under speakers' control. Finally, experiments on dialect comprehension and identification demonstrate that listeners have detailed cognitive associations of language variants with groups of people, whether or not they can produce the same variants themselves. A model is presented for how sociolinguistic knowledge can be viewed in relation to other parts of language with regard to cognitive and neural representations. WIREs Cogni Sci 2011 2 701-716 DOI: 10.1002/wcs.152 For further resources related to this article, please visit the WIREs website. Copyright © 2011 John Wiley & Sons, Ltd.

Allele frequencies of variants in ultra conserved elements identify selective pressure on transcription factor binding.

Directory of Open Access Journals (Sweden)

Toomas Silla

Full Text Available Ultra-conserved genes or elements (UCGs/UCEs in the human genome are extreme examples of conservation. We characterized natural variations in 2884 UCEs and UCGs in two distinct populations; Singaporean Chinese (n = 280 and Italian (n = 501 by using a pooled sample, targeted capture, sequencing approach. We identify, with high confidence, in these regions the abundance of rare SNVs (MAF5% are more often found in relatively less-conserved nucleotides within UCEs, compared to rare variants. Moreover, prevalent variants are less likely to overlap transcription factor binding site. Using SNPfold we found no significant influence of RNA secondary structure on UCE conservation. All together, these results suggest UCEs are not under selective pressure as a stretch of DNA but are under differential evolutionary pressure on the single nucleotide level.

Improving accuracy of rare variant imputation with a two-step imputation approach

DEFF Research Database (Denmark)

Kreiner-Møller, Eskil; Medina-Gomez, Carolina; Uitterlinden, André G

2015-01-01

not being comprehensively scrutinized. Next-generation arrays ensuring sufficient coverage together with new reference panels, as the 1000 Genomes panel, are emerging to facilitate imputation of low frequent single-nucleotide polymorphisms (minor allele frequency (MAF) ... reference sample genotyped on a dense array and hereafter to the 1000 Genomes reference panel. We show that mean imputation quality, measured by the r(2) using this approach, increases by 28% for variants with a MAF between 1 and 5% as compared with direct imputation to 1000 Genomes reference. Similarly......Genotype imputation has been the pillar of the success of genome-wide association studies (GWAS) for identifying common variants associated with common diseases. However, most GWAS have been run using only 60 HapMap samples as reference for imputation, meaning less frequent and rare variants...

The Allelic Landscape of Human Blood Cell Trait Variation and Links to Common Complex Disease.

Science.gov (United States)

Astle, William J; Elding, Heather; Jiang, Tao; Allen, Dave; Ruklisa, Dace; Mann, Alice L; Mead, Daniel; Bouman, Heleen; Riveros-Mckay, Fernando; Kostadima, Myrto A; Lambourne, John J; Sivapalaratnam, Suthesh; Downes, Kate; Kundu, Kousik; Bomba, Lorenzo; Berentsen, Kim; Bradley, John R; Daugherty, Louise C; Delaneau, Olivier; Freson, Kathleen; Garner, Stephen F; Grassi, Luigi; Guerrero, Jose; Haimel, Matthias; Janssen-Megens, Eva M; Kaan, Anita; Kamat, Mihir; Kim, Bowon; Mandoli, Amit; Marchini, Jonathan; Martens, Joost H A; Meacham, Stuart; Megy, Karyn; O'Connell, Jared; Petersen, Romina; Sharifi, Nilofar; Sheard, Simon M; Staley, James R; Tuna, Salih; van der Ent, Martijn; Walter, Klaudia; Wang, Shuang-Yin; Wheeler, Eleanor; Wilder, Steven P; Iotchkova, Valentina; Moore, Carmel; Sambrook, Jennifer; Stunnenberg, Hendrik G; Di Angelantonio, Emanuele; Kaptoge, Stephen; Kuijpers, Taco W; Carrillo-de-Santa-Pau, Enrique; Juan, David; Rico, Daniel; Valencia, Alfonso; Chen, Lu; Ge, Bing; Vasquez, Louella; Kwan, Tony; Garrido-Martín, Diego; Watt, Stephen; Yang, Ying; Guigo, Roderic; Beck, Stephan; Paul, Dirk S; Pastinen, Tomi; Bujold, David; Bourque, Guillaume; Frontini, Mattia; Danesh, John; Roberts, David J; Ouwehand, Willem H; Butterworth, Adam S; Soranzo, Nicole

2016-11-17

Many common variants have been associated with hematological traits, but identification of causal genes and pathways has proven challenging. We performed a genome-wide association analysis in the UK Biobank and INTERVAL studies, testing 29.5 million genetic variants for association with 36 red cell, white cell, and platelet properties in 173,480 European-ancestry participants. This effort yielded hundreds of low frequency (<5%) and rare (<1%) variants with a strong impact on blood cell phenotypes. Our data highlight general properties of the allelic architecture of complex traits, including the proportion of the heritable component of each blood trait explained by the polygenic signal across different genome regulatory domains. Finally, through Mendelian randomization, we provide evidence of shared genetic pathways linking blood cell indices with complex pathologies, including autoimmune diseases, schizophrenia, and coronary heart disease and evidence suggesting previously reported population associations between blood cell indices and cardiovascular disease may be non-causal. Copyright © 2016 Elsevier Inc. All rights reserved.

[Association analysis of SNP-63 and indel-19 variant in the calpain-10 gene with polycystic ovary syndrome in women of reproductive age].

Science.gov (United States)

Flores-Martínez, Silvia Esperanza; Castro-Martínez, Anna Gabriela; López-Quintero, Andrés; García-Zapién, Alejandra Guadalupe; Torres-Rodríguez, Ruth Noemí; Sánchez-Corona, José

2015-01-01

Polycystic ovary syndrome is a complex and heterogeneous disease involving both reproductive and metabolic problems. It has been suggested a genetic predisposition in the etiology of this syndrome. The identification of calpain-10 gene (CAPN10) as the first candidate gene for type 2 diabetes mellitus, has focused the interest in investigating their possible relation with the polycystic ovary syndrome, because this syndrome is associated with hyperinsulinemia and insulin resistance, two metabolic abnormalities associated with type 2 diabetes mellitus. To investigate if there is association between the SNP-63 and the variant indel-19 of the CAPN10 gene and polycystic ovary syndrome in women of reproductive age. This study included 101 women (55 with polycystic ovary syndrome and 46 without polycystic ovary syndrome). The genetic variant indel-19 was identified by electrophoresis of the amplified fragments by PCR, and the SNP-63 by PCR-RFLP. The allele and genotype frequencies of the two variants do not differ significatly between women with polycystic ovary syndrome and control women group. The haplotype 21 (defined by the insertion allele of indel-19 variant and C allele of SNP-63) was found with higher frequency in both study groups, being more frequent in the polycystic ovary syndrome patients group, however, this difference was not statistically significant (p = 0.8353). The results suggest that SNP-63 and indel-19 variant of the CAPN10 gene do not represent a risk factor for polycystic ovary syndrome in our patients group. Copyright © 2015. Published by Masson Doyma México S.A.

Systematic identification of regulatory variants associated with cancer risk.

Science.gov (United States)

Liu, Song; Liu, Yuwen; Zhang, Qin; Wu, Jiayu; Liang, Junbo; Yu, Shan; Wei, Gong-Hong; White, Kevin P; Wang, Xiaoyue

2017-10-23

Most cancer risk-associated single nucleotide polymorphisms (SNPs) identified by genome-wide association studies (GWAS) are noncoding and it is challenging to assess their functional impacts. To systematically identify the SNPs that affect gene expression by modulating activities of distal regulatory elements, we adapt the self-transcribing active regulatory region sequencing (STARR-seq) strategy, a high-throughput technique to functionally quantify enhancer activities. From 10,673 SNPs linked with 996 cancer risk-associated SNPs identified in previous GWAS studies, we identify 575 SNPs in the fragments that positively regulate gene expression, and 758 SNPs in the fragments with negative regulatory activities. Among them, 70 variants are regulatory variants for which the two alleles confer different regulatory activities. We analyze in depth two regulatory variants-breast cancer risk SNP rs11055880 and leukemia risk-associated SNP rs12142375-and demonstrate their endogenous regulatory activities on expression of ATF7IP and PDE4B genes, respectively, using a CRISPR-Cas9 approach. By identifying regulatory variants associated with cancer susceptibility and studying their molecular functions, we hope to help the interpretation of GWAS results and provide improved information for cancer risk assessment.

Deletion mutant defines DQ beta variants with DR4 positive DQw3 positive haplotypes

International Nuclear Information System (INIS)

Nepom, B.S.; Kim, S.J.; Nepom, G.T.

1986-01-01

We describe the production of an HLA deletion mutation by radiation mutagenesis of a DR4- and DQw3-homozygous, Dw4- and Dw14-heterozygous cell line designed to analyze polymorphisms associated with DR4 and DQw3. Southern blot analysis confirms a deletion of class I and class II genes on one haplotype. Variation in DQ beta alleles associated with DQw3 was previously described by characteristic RFLP patterns for a DQ beta bene. One pattern, which correlated precisely with A-10-83 monoclonal antibody reactivity (TA10), defined an allele which we call DQ''3.1''. The mutant cell line has lost the polymorphic bands on Southern blots corresponding to the DQ''3.1'' allele, while the intact Dw14 haplotype retains the alternate allele at DQ beta which is DQw-3 positive. TA10-negative. These data demonstrate the segregation of two DQw3 positive DQ beta allelic variants, both associated with DR4, which can be distinguished on the basis of both RFLP and monoclonal antibody reactivity

Lack of association between the P413L variant of chromogranin B and ALS risk or age at onset: a meta-analysis.

Science.gov (United States)

Yang, Xinglong; Li, Shimei; Xing, Dongmei; Li, Peiyun; Li, Ci; Qi, Ling; Xu, Yanming; Ren, Hui

2018-02-01

Amyotrophic lateral sclerosis (ALS), the most common motor neuron disease, is thought to result from interaction of genetic and environmental risk factors. Whether the potentially functional exonic P413L variant in the chromogranin B gene influences ALS risk and age at onset is controversial. We meta-analysed or other studies assessing the association between the P413L variant and ALS risk or age at ALS onset indexed in Web of Science, PubMed, Embase, Chinese National Knowledge Infrastructure, Wanfang, and SinoMed databases. Five case-control studies were analysed, involving 2639 patients with sporadic ALS, 201 with familial ALS and 3381 controls. No association was detected between risk of either ALS type and the CT + TT genotype or T-allele of the P413L variant. Age at ALS onset was similar between carriers and non-carriers of the T-allele. The available evidence suggests that the P413L variant of chromogranin B is not associated with ALS risk or age at ALS onset. These results should be validated in large, well-designed studies.

Association of polymorphic variants of PTPN22, TNF and VDR genes in children with lupus nephritis: A study in Colombian family triads.

Science.gov (United States)

Garavito, Gloria; Egea, Eduardo; Fang, Luis; Malagón, Clara; Olmos, Carlos; González, Luz; Guarnizo, Pilar; Aroca, Gustavo; López, Guillermo; Iglesias, Antonio

2017-06-01

Systemic lupus erythematosus is an autoimmune disease in which the severity varies according to race, sex and age of onset. This variation is also observed in the genetic markers associated with the disease, including PTPN22, VDR and TNF genes. The genetic stratification in different populations worldwide can influence the variability. To analyze the heritability of PTPN22, VDR and TNF genetic variants and their association with pediatric lupus nephritis in Colombian families. We conducted a family-based study including 46 triads (case, father and mother). The variants rs2476601 of PTPN22; rs361525 and rs1800629 of TNF, and TaqI [rs731236], ApaI [rs7975232], BsmI [rs1544410] and FokI [rs2228570] of VDR were genotyped by qPCR. The effects of overtransmission of the risk allele from parents to children and linkage disequilibrium at the VDR and TNF loci were estimated. We found that allele A of rs2476601 in PTPN22 was distributed among 8.69 % (n=16) of the parents and 19.5 % (n=18) of the cases; this allele was overtransmitted from parents to children 17 times more often than the G allele (p=0.028). TNF and VDR polymorphisms did not exhibit transmission disequilibrium. VDR TaqI, ApaI and BsmI variants exhibited linkage disequilibrium. These findings showed an association between the PTPN22 rs2476601 polymorphism and pediatric lupus nephritis due to its overtransmission in the group of families studied.

High-specificity detection of rare alleles with Paired-End Low Error Sequencing (PELE-Seq).

Science.gov (United States)

Preston, Jessica L; Royall, Ariel E; Randel, Melissa A; Sikkink, Kristin L; Phillips, Patrick C; Johnson, Eric A

2016-06-14

Polymorphic loci exist throughout the genomes of a population and provide the raw genetic material needed for a species to adapt to changes in the environment. The minor allele frequencies of rare Single Nucleotide Polymorphisms (SNPs) within a population have been difficult to track with Next-Generation Sequencing (NGS), due to the high error rate of standard methods such as Illumina sequencing. We have developed a wet-lab protocol and variant-calling method that identifies both sequencing and PCR errors, called Paired-End Low Error Sequencing (PELE-Seq). To test the specificity and sensitivity of the PELE-Seq method, we sequenced control E. coli DNA libraries containing known rare alleles present at frequencies ranging from 0.2-0.4 % of the total reads. PELE-Seq had higher specificity and sensitivity than standard libraries. We then used PELE-Seq to characterize rare alleles in a Caenorhabditis remanei nematode worm population before and after laboratory adaptation, and found that minor and rare alleles can undergo large changes in frequency during lab-adaptation. We have developed a method of rare allele detection that mitigates both sequencing and PCR errors, called PELE-Seq. PELE-Seq was evaluated using control E. coli populations and was then used to compare a wild C. remanei population to a lab-adapted population. The PELE-Seq method is ideal for investigating the dynamics of rare alleles in a broad range of reduced-representation sequencing methods, including targeted amplicon sequencing, RAD-Seq, ddRAD, and GBS. PELE-Seq is also well-suited for whole genome sequencing of mitochondria and viruses, and for high-throughput rare mutation screens.

Common variants near MC4R are associated with fat mass, weight and risk of obesity

Science.gov (United States)

Loos, Ruth J F; Lindgren, Cecilia M; Li, Shengxu; Wheeler, Eleanor; Zhao, Jing Hua; Prokopenko, Inga; Inouye, Michael; Freathy, Rachel M; Attwood, Antony P; Beckmann, Jacques S; Berndt, Sonja I; Bergmann, Sven; Bennett, Amanda J; Bingham, Sheila A; Bochud, Murielle; Brown, Morris; Cauchi, Stéphane; Connell, John M; Cooper, Cyrus; Smith, George Davey; Day, Ian; Dina, Christian; De, Subhajyoti; Dermitzakis, Emmanouil T; Doney, Alex S F; Elliott, Katherine S; Elliott, Paul; Evans, David M; Farooqi, I Sadaf; Froguel, Philippe; Ghori, Jilur; Groves, Christopher J; Gwilliam, Rhian; Hadley, David; Hall, Alistair S; Hattersley, Andrew T; Hebebrand, Johannes; Heid, Iris M; Herrera, Blanca; Hinney, Anke; Hunt, Sarah E; Jarvelin, Marjo-Riitta; Johnson, Toby; Jolley, Jennifer D M; Karpe, Fredrik; Keniry, Andrew; Khaw, Kay-Tee; Luben, Robert N; Mangino, Massimo; Marchini, Jonathan; McArdle, Wendy L; McGinnis, Ralph; Meyre, David; Munroe, Patricia B; Morris, Andrew D; Ness, Andrew R; Neville, Matthew J; Nica, Alexandra C; Ong, Ken K; O'Rahilly, Stephen; Owen, Katharine R; Palmer, Colin N A; Papadakis, Konstantinos; Potter, Simon; Pouta, Anneli; Qi, Lu; Randall, Joshua C; Rayner, Nigel W; Ring, Susan M; Sandhu, Manjinder S; Scherag, André; Sims, Matthew A; Song, Kijoung; Soranzo, Nicole; Speliotes, Elizabeth K; Syddall, Holly E; Teichmann, Sarah A; Timpson, Nicholas J; Tobias, Jonathan H; Uda, Manuela; Vogel, Carla I Ganz; Wallace, Chris; Waterworth, Dawn M; Weedon, Michael N; Willer, Cristen J; Wraight, Vicki L; Yuan, Xin; Zeggini, Eleftheria; Hirschhorn, Joel N; Strachan, David P; Ouwehand, Willem H; Caulfield, Mark J; Samani, Nilesh J; Frayling, Timothy M; Vollenweider, Peter; Waeber, Gerard; Mooser, Vincent; Deloukas, Panos; McCarthy, Mark I; Wareham, Nicholas J; Barroso, Inês; Jacobs, Kevin B; Chanock, Stephen J; Hayes, Richard B; Lamina, Claudia; Gieger, Christian; Illig, Thomas; Meitinger, Thomas; Wichmann, H-Erich; Kraft, Peter; Hankinson, Susan E; Hunter, David J; Hu, Frank B; Lyon, Helen N; Voight, Benjamin F; Ridderstrale, Martin; Groop, Leif; Scheet, Paul; Sanna, Serena; Abecasis, Goncalo R; Albai, Giuseppe; Nagaraja, Ramaiah; Schlessinger, David; Jackson, Anne U; Tuomilehto, Jaakko; Collins, Francis S; Boehnke, Michael; Mohlke, Karen L

2009-01-01

To identify common variants influencing body mass index (BMI), we analyzed genome-wide association data from 16,876 individuals of European descent. After previously reported variants in FTO, the strongest association signal (rs17782313, P = 2.9 × 10−6) mapped 188 kb downstream of MC4R (melanocortin-4 receptor), mutations of which are the leading cause of monogenic severe childhood-onset obesity. We confirmed the BMI association in 60,352 adults (per-allele effect = 0.05 Z-score units; P = 2.8 × 10−15) and 5,988 children aged 7–11 (0.13 Z-score units; P = 1.5 × 10−8). In case-control analyses (n = 10,583), the odds for severe childhood obesity reached 1.30 (P = 8.0 × 10−11). Furthermore, we observed overtransmission of the risk allele to obese offspring in 660 families (P (pedigree disequilibrium test average; PDT-avg) = 2.4 × 10−4). The SNP location and patterns of phenotypic associations are consistent with effects mediated through altered MC4R function. Our findings establish that common variants near MC4R influence fat mass, weight and obesity risk at the population level and reinforce the need for large-scale data integration to identify variants influencing continuous biomedical traits. PMID:18454148

Short, natural, and extended photoperiod response in BC2F4 lines of bread wheat with different photoperiod-1 (Ppd-1) alleles.

Science.gov (United States)

Bentley, A R; Horsnell, R; Werner, C P; Turner, A S; Rose, G A; Bedard, C; Howell, P; Wilhelm, E P; Mackay, I J; Howells, R M; Greenland, A; Laurie, D A; Gosman, N

2013-04-01

Flowering is a critical period in the life cycle of flowering plant species, resulting in an irreversible commitment of significant resources. Wheat is photoperiod sensitive, flowering only when daylength surpasses a critical length; however, photoperiod insensitivity (PI) has been selected by plant breeders for >40 years to enhance yield in certain environments. Control of flowering time has been greatly facilitated by the development of molecular markers for the Photoperiod-1 (Ppd-1) homeoloci, on the group 2 chromosomes. In the current study, an allelic series of BC2F4 lines in the winter wheat cultivars 'Robigus' and 'Alchemy' was developed to elucidate the influence on flowering of eight gene variants from the B- and D-genomes of bread wheat and the A-genome of durum wheat. Allele effects were tested in short, natural, and extended photoperiods in the field and controlled environments. Across genetic background and treatment, the D-genome PI allele, Ppd-D1a, had a more potent effect on reducing flowering time than Ppd-B1a. However, there was significant donor allele effect for both Ppd-D1a and Ppd-B1a, suggesting the presence of linked modifier genes and/or additional sources of latent sensitivity. Development of Ppd-A1a BC2F4 lines derived from synthetic hexaploid wheat provided an opportunity to compare directly the flowering time effect of the A-genome allele from durum with the B- and D-genome variants from bread wheat for the first time. Analyses indicated that the reducing effect of Ppd-A1a is comparable with that of Ppd-D1a, confirming it as a useful alternative source of PI.

Uncovering the Neural Bases of Cognitive and Affective Empathy Deficits in Alzheimer's Disease and the Behavioral-Variant of Frontotemporal Dementia.

Science.gov (United States)

Dermody, Nadene; Wong, Stephanie; Ahmed, Rebekah; Piguet, Olivier; Hodges, John R; Irish, Muireann

2016-05-30

Loss of empathy is a core presenting feature of the behavioral-variant of frontotemporal dementia (bvFTD), resulting in socioemotional difficulties and behavioral transgressions. In contrast, interpersonal functioning remains relatively intact in Alzheimer's disease (AD), despite marked cognitive decline. The neural substrates mediating these patterns of loss and sparing in social functioning remain unclear, yet are relevant for our understanding of the social brain. We investigated cognitive versus affective aspects of empathy using the Interpersonal Reactivity Index (IRI) in 25 AD and 24 bvFTD patients and contrasted their performance with 22 age- and education-matched controls. Cognitive empathy was comparably compromised in AD and bvFTD, whereas affective empathy was impaired exclusively in bvFTD. While controlling for overall cognitive dysfunction ameliorated perspective-taking deficits in AD, empathy loss persisted across cognitive and affective domains in bvFTD. Voxel-based morphometry analyses revealed divergent neural substrates of empathy loss in each patient group. Perspective-taking deficits correlated with predominantly left-sided temporoparietal atrophy in AD, whereas widespread bilateral frontoinsular, temporal, parietal, and occipital atrophy was implicated in bvFTD. Reduced empathic concern in bvFTD was associated with atrophy in the left orbitofrontal, inferior frontal, and insular cortices, and the bilateral mid-cingulate gyrus. Our findings suggest that social cognitive deficits in AD arise largely as a consequence of global cognitive dysfunction, rather than a loss of empathy per se. In contrast, loss of empathy in bvFTD reflects the deterioration of a distributed network of frontoinsular and temporal structures that appear crucial for monitoring and processing social information.

A variant in CDKAL1 influences insulin response and risk of type 2 diabetes

DEFF Research Database (Denmark)

Steinthorsdottir, Valgerdur; Thorleifsson, Gudmar; Reynisdottir, Inga

2007-01-01

We conducted a genome-wide association study for type 2 diabetes (T2D) in Icelandic cases and controls, and we found that a previously described variant in the transcription factor 7-like 2 gene (TCF7L2) gene conferred the most significant risk. In addition to confirming two recently identified...... risk variants, we identified a variant in the CDKAL1 gene that was associated with T2D in individuals of European ancestry (allele-specific odds ratio (OR) = 1.20 (95% confidence interval, 1.13-1.27), P = 7.7 x 10(-9)) and individuals from Hong Kong of Han Chinese ancestry (OR = 1.25 (1.11-1.40), P = 0...... was approximately 20% lower than for heterozygotes or noncarriers, suggesting that this variant confers risk of T2D through reduced insulin secretion....

Circadian gene variants and susceptibility to type 2 diabetes: a pilot study.

Directory of Open Access Journals (Sweden)

M Ann Kelly

Full Text Available Disruption of endogenous circadian rhythms has been shown to increase the risk of developing type 2 diabetes, suggesting that circadian genes might play a role in determining disease susceptibility. We present the results of a pilot study investigating the association between type 2 diabetes and selected single nucleotide polymorphisms (SNPs in/near nine circadian genes. The variants were chosen based on their previously reported association with prostate cancer, a disease that has been suggested to have a genetic link with type 2 diabetes through a number of shared inherited risk determinants.The pilot study was performed using two genetically homogeneous Punjabi cohorts, one resident in the United Kingdom and one indigenous to Pakistan. Subjects with (N = 1732 and without (N = 1780 type 2 diabetes were genotyped for thirteen circadian variants using a competitive allele-specific polymerase chain reaction method. Associations between the SNPs and type 2 diabetes were investigated using logistic regression. The results were also combined with in silico data from other South Asian datasets (SAT2D consortium and white European cohorts (DIAGRAM+ using meta-analysis. The rs7602358G allele near PER2 was negatively associated with type 2 diabetes in our Punjabi cohorts (combined odds ratio [OR] = 0.75 [0.66-0.86], p = 3.18 × 10(-5, while the BMAL1 rs11022775T allele was associated with an increased risk of the disease (combined OR = 1.22 [1.07-1.39], p = 0.003. Neither of these associations was replicated in the SAT2D or DIAGRAM+ datasets, however. Meta-analysis of all the cohorts identified disease associations with two variants, rs2292912 in CRY2 and rs12315175 near CRY1, although statistical significance was nominal (combined OR = 1.05 [1.01-1.08], p = 0.008 and OR = 0.95 [0.91-0.99], p = 0.015 respectively.None of the selected circadian gene variants was associated with type 2 diabetes with study-wide significance after meta-analysis. The nominal

Inhibitory potency of 8-methoxypsoralen on cytochrome P450 2A6 (CYP2A6 allelic variants CYP2A6 15, CYP2A6 16, CYP2A6 21 and CYP2A6 22: differential susceptibility due to different sequence locations of the mutations.

Directory of Open Access Journals (Sweden)

Kai Hung Tiong

Full Text Available Human cytochrome P450 2A6 (CYP2A6 is a highly polymorphic isoform of CYP2A subfamily. Our previous kinetic study on four CYP2A6 allelic variants (CYP2A6 15, CYP2A6 16, CYP2A6 21 and CYP2A6 22 have unveiled the functional significance of sequence mutations in these variants on coumarin 7-hydroxylation activity. In the present study, we further explored the ability of a typical CYP2A6 inhibitor, 8-methoxypsoralen (8-MOP, in inhibition of these alleles and we hypothesized that translational mutations in these variants are likely to give impact on 8-MOP inhibitory potency. The CYP2A6 variant and the wild type proteins were subjected to 8-MOP inhibition to yield IC50 values. In general, a similar trend of change in the IC50 and Km values was noted among the four mutants towards coumarin oxidation. With the exception of CYP2A6 16, differences in IC50 values were highly significant which implied compromised interaction of the mutants with 8-MOP. Molecular models of CYP2A6 were subsequently constructed and ligand-docking experiments were performed to rationalize experimental data. Our docking study has shown that mutations have induced enlargement of the active site volume in all mutants with the exception of CYP2A6 16. Furthermore, loss of hydrogen bond between 8-MOP and active site residue Asn297 was evidenced in all mutants. Our data indicate that the structural changes elicited by the sequence mutations could affect 8-MOP binding to yield differential enzymatic activities in the mutant CYP2A6 proteins.

wANNOVAR: annotating genetic variants for personal genomes via the web.

Science.gov (United States)

Chang, Xiao; Wang, Kai

2012-07-01

High-throughput DNA sequencing platforms have become widely available. As a result, personal genomes are increasingly being sequenced in research and clinical settings. However, the resulting massive amounts of variants data pose significant challenges to the average biologists and clinicians without bioinformatics skills. We developed a web server called wANNOVAR to address the critical needs for functional annotation of genetic variants from personal genomes. The server provides simple and intuitive interface to help users determine the functional significance of variants. These include annotating single nucleotide variants and insertions/deletions for their effects on genes, reporting their conservation levels (such as PhyloP and GERP++ scores), calculating their predicted functional importance scores (such as SIFT and PolyPhen scores), retrieving allele frequencies in public databases (such as the 1000 Genomes Project and NHLBI-ESP 5400 exomes), and implementing a 'variants reduction' protocol to identify a subset of potentially deleterious variants/genes. We illustrated how wANNOVAR can help draw biological insights from sequencing data, by analysing genetic variants generated on two Mendelian diseases. We conclude that wANNOVAR will help biologists and clinicians take advantage of the personal genome information to expedite scientific discoveries. The wANNOVAR server is available at http://wannovar.usc.edu, and will be continuously updated to reflect the latest annotation information.

The BARD1 Cys557Ser variant and breast cancer risk in Iceland.

Directory of Open Access Journals (Sweden)

Simon N Stacey

2006-07-01

Full Text Available Most, if not all, of the cellular functions of the BRCA1 protein are mediated through heterodimeric complexes composed of BRCA1 and a related protein, BARD1. Some breast-cancer-associated BRCA1 missense mutations disrupt the function of the BRCA1/BARD1 complex. It is therefore pertinent to determine whether variants of BARD1 confer susceptibility to breast cancer. Recently, a missense BARD1 variant, Cys557Ser, was reported to be at increased frequencies in breast cancer families. We investigated the role of the BARD1 Cys557Ser variant in a population-based cohort of 1,090 Icelandic patients with invasive breast cancer and 703 controls. We then used a computerized genealogy of the Icelandic population to study the relationships between the Cys557Ser variant and familial clustering of breast cancer.The Cys557Ser allele was present at a frequency of 0.028 in patients with invasive breast cancer and 0.016 in controls (odds ratio [OR] = 1.82, 95% confidence interval [CI] 1.11-3.01, p = 0.014. The alleleic frequency was 0.037 in a high-predisposition group of cases defined by having a family history of breast cancer, early onset of breast cancer, or multiple primary breast cancers (OR = 2.41, 95% CI 1.22-4.75, p = 0.015. Carriers of the common Icelandic BRCA2 999del5 mutation were found to have their risk of breast cancer further increased if they also carried the BARD1 variant: the frequency of the BARD1 variant allele was 0.047 (OR = 3.11, 95% CI 1.16-8.40, p = 0.046 in 999del5 carriers with breast cancer. This suggests that the lifetime probability of a BARD1 Cys557Ser/BRCA2 999del5 double carrier developing breast cancer could approach certainty. Cys557Ser carriers, with or without the BRCA2 mutation, had an increased risk of subsequent primary breast tumors after the first breast cancer diagnosis compared to non-carriers. Lobular and medullary breast carcinomas were overrepresented amongst Cys557Ser carriers. We found that an excess of ancestors

DCLK1 variants are associated across schizophrenia and attention deficit/hyperactivity disorder.

Directory of Open Access Journals (Sweden)

Bjarte Håvik

Full Text Available Doublecortin and calmodulin like kinase 1 (DCLK1 is implicated in synaptic plasticity and neurodevelopment. Genetic variants in DCLK1 are associated with cognitive traits, specifically verbal memory and general cognition. We investigated the role of DCLK1 variants in three psychiatric disorders that have neuro-cognitive dysfunctions: schizophrenia (SCZ, bipolar affective disorder (BP and attention deficit/hyperactivity disorder (ADHD. We mined six genome wide association studies (GWASs that were available publically or through collaboration; three for BP, two for SCZ and one for ADHD. We also genotyped the DCLK1 region in additional samples of cases with SCZ, BP or ADHD and controls that had not been whole-genome typed. In total, 9895 subjects were analysed, including 5308 normal controls and 4,587 patients (1,125 with SCZ, 2,496 with BP and 966 with ADHD. Several DCLK1 variants were associated with disease phenotypes in the different samples. The main effect was observed for rs7989807 in intron 3, which was strongly associated with SCZ alone and even more so when cases with SCZ and ADHD were combined (P-value = 4 × 10(-5 and 4 × 10(-6, respectively. Associations were also observed with additional markers in intron 3 (combination of SCZ, ADHD and BP, intron 19 (SCZ+BP and the 3'UTR (SCZ+BP. Our results suggest that genetic variants in DCLK1 are associated with SCZ and, to a lesser extent, with ADHD and BP. Interestingly the association is strongest when SCZ and ADHD are considered together, suggesting common genetic susceptibility. Given that DCLK1 variants were previously found to be associated with cognitive traits, these results are consistent with the role of DCLK1 in neurodevelopment and synaptic plasticity.

Modulation of Malaria Phenotypes by Pyruvate Kinase (PKLR Variants in a Thai Population.

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Rebekah van Bruggen

Full Text Available Pyruvate kinase (PKLR is a critical erythrocyte enzyme that is required for glycolysis and production of ATP. We have shown that Pklr deficiency in mice reduces the severity (reduced parasitemia, increased survival of blood stage malaria induced by infection with Plasmodium chabaudi AS. Likewise, studies in human erythrocytes infected ex vivo with P. falciparum show that presence of host PK-deficiency alleles reduces infection phenotypes. We have characterized the genetic diversity of the PKLR gene, including haplotype structure and presence of rare coding variants in two populations from malaria endemic areas of Thailand and Senegal. We investigated the effect of PKLR genotypes on rich longitudinal datasets including haematological and malaria-associated phenotypes. A coding and possibly damaging variant (R41Q was identified in the Thai population with a minor allele frequency of ~4.7%. Arginine 41 (R41 is highly conserved in the pyruvate kinase family and its substitution to Glutamine (R41Q affects protein stability. Heterozygosity for R41Q is shown to be associated with a significant reduction in the number of attacks with Plasmodium falciparum, while correlating with an increased number of Plasmodium vivax infections. These results strongly suggest that PKLR protein variants may affect the frequency, and the intensity of malaria episodes induced by different Plasmodium parasites in humans living in areas of endemic malaria.

Polymorphism discovery and allele frequency estimation using high-throughput DNA sequencing of target-enriched pooled DNA samples

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Mullen Michael P

2012-01-01

Full Text Available Abstract Background The central role of the somatotrophic axis in animal post-natal growth, development and fertility is well established. Therefore, the identification of genetic variants affecting quantitative traits within this axis is an attractive goal. However, large sample numbers are a pre-requisite for the identification of genetic variants underlying complex traits and although technologies are improving rapidly, high-throughput sequencing of large numbers of complete individual genomes remains prohibitively expensive. Therefore using a pooled DNA approach coupled with target enrichment and high-throughput sequencing, the aim of this study was to identify polymorphisms and estimate allele frequency differences across 83 candidate genes of the somatotrophic axis, in 150 Holstein-Friesian dairy bulls divided into two groups divergent for genetic merit for fertility. Results In total, 4,135 SNPs and 893 indels were identified during the resequencing of the 83 candidate genes. Nineteen percent (n = 952 of variants were located within 5' and 3' UTRs. Seventy-two percent (n = 3,612 were intronic and 9% (n = 464 were exonic, including 65 indels and 236 SNPs resulting in non-synonymous substitutions (NSS. Significant (P ® MassARRAY. No significant differences (P > 0.1 were observed between the two methods for any of the 43 SNPs across both pools (i.e., 86 tests in total. Conclusions The results of the current study support previous findings of the use of DNA sample pooling and high-throughput sequencing as a viable strategy for polymorphism discovery and allele frequency estimation. Using this approach we have characterised the genetic variation within genes of the somatotrophic axis and related pathways, central to mammalian post-natal growth and development and subsequent lactogenesis and fertility. We have identified a large number of variants segregating at significantly different frequencies between cattle groups divergent for calving

Common genetic variants are significant risk factors for early menopause: results from the Breakthrough Generations Study.

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Murray, Anna; Bennett, Claire E; Perry, John R B; Weedon, Michael N; Jacobs, Patricia A; Morris, Danielle H; Orr, Nicholas; Schoemaker, Minouk J; Jones, Michael; Ashworth, Alan; Swerdlow, Anthony J

2011-01-01

Women become infertile approximately 10 years before menopause, and as more women delay childbirth into their 30s, the number of women who experience infertility is likely to increase. Tests that predict the timing of menopause would allow women to make informed reproductive decisions. Current predictors are only effective just prior to menopause, and there are no long-range indicators. Age at menopause and early menopause (EM) are highly heritable, suggesting a genetic aetiology. Recent genome-wide scans have identified four loci associated with variation in the age of normal menopause (40-60 years). We aimed to determine whether theses loci are also risk factors for EM. We tested the four menopause-associated genetic variants in a cohort of approximately 2000 women with menopause≤45 years from the Breakthrough Generations Study (BGS). All four variants significantly increased the odds of having EM. Comparing the 4.5% of individuals with the lowest number of risk alleles (two or three) with the 3.0% with the highest number (eight risk alleles), the odds ratio was 4.1 (95% CI 2.4-7.1, P=4.0×10(-7)). In combination, the four variants discriminated EM cases with a receiver operator characteristic area under the curve of 0.6. Four common genetic variants identified by genome-wide association studies, had a significant impact on the odds of having EM in an independent cohort from the BGS. The discriminative power is still limited, but as more variants are discovered they may be useful for predicting reproductive lifespan.

Behavioral variant of frontotemporal dementia mimicking Huntington's disease

DEFF Research Database (Denmark)

Nielsen, T Rune; Bruhn, Peter; Nielsen, Jørgen E

2010-01-01

Behavioral changes and cognitive decline are the core clinical manifestations in the behavioral variant of frontotemporal dementia (bv-FTD). The behavioral changes may include characteristic stereotypic movements. These movements, although without clear purpose, are not involuntary. Involuntary...

Frequency of the ATM IVS10-6T→G variant in Australian multiple-case breast cancer families

International Nuclear Information System (INIS)

Lindeman, Geoffrey J; Suthers, Graeme; Kirk, Judy; Hiew, Melody; Visvader, Jane E; Leary, Jennifer; Field, Michael; Gaff, Clara L; Gardner, RJ McKinlay; Trainor, Kevin; Cheetham, Glenice

2004-01-01

Germline mutations in the genes BRCA1 and BRCA2 account for only a proportion of hereditary breast cancer, suggesting that additional genes contribute to hereditary breast cancer. Recently a heterozygous variant in the ataxia–telangiectasia mutated (ATM) gene, IVS10-6T→G, was reported by an Australian multiple-case breast cancer family cohort study (the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer) to confer a substantial breast cancer risk. Although this variant can result in a truncated ATM product, its clinical significance as a high-penetrance breast cancer allele or its role as a low-penetrance risk-modifier is controversial. We determined the frequency of ATM IVS10-6T→G variants in a cohort of individuals affected by breast and/or ovarian cancer who underwent BRCA1 and BRCA2 genetic testing at four major Australian familial cancer clinics. Seven of 495 patients (1.4%) were heterozygous for the IVS10-6T→G variant; the carrier rate in unselected Australian women with no family history of breast cancer is reported to be 6 of 725 (0.83%) (P = 0.4). Two of the seven probands also harboured a pathogenic BRCA1 mutation and one patient had a BRCA1 unclassified variant of uncertain significance. These findings indicate that the ATM IVS10-6T→G variant does not seem to occur at a significantly higher frequency in affected individuals from high-risk families than in the general population. A role for this variant as a low-penetrance allele or as a modifying gene in association with other genes (such as BRCA1) remains possible. Routine testing for ATM IVS10-6T→G is not warranted in mutation screening of affected individuals from high-risk families

Allelic Frequencies of 20 Visible Phenotype Variants in the Korean Population

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Ji Eun Lim

2013-06-01

Full Text Available The prediction of externally visible characteristics from DNA has been studied for forensic genetics over the last few years. Externally visible characteristics include hair, skin, and eye color, height, and facial morphology, which have high heritability. Recent studies using genome-wide association analysis have identified genes and variations that correlate with human visible phenotypes and developed phenotype prediction programs. However, most prediction models were constructed and validated based on genotype and phenotype information on Europeans. Therefore, we need to validate prediction models in diverse ethnic populations. In this study, we selected potentially useful variations for forensic science that are associated with hair and eye color, iris pattern, and facial morphology, based on previous studies, and analyzed their frequencies in 1,920 Koreans. Among 20 single nucleotide polymorphisms (SNPs, 10 SNPs were polymorphic, 6 SNPs were very rare (minor allele frequency < 0.005, and 4 SNPs were monomorphic in the Korean population. Even though the usability of these SNPs should be verified by an association study in Koreans, this study provides 10 potential SNP markers for forensic science for externally visible characteristics in the Korean population.

A study of the M235T variant of the angiotensinogen gene and ...

African Journals Online (AJOL)

Mary E. Kooffreh

2012-08-11

Aug 11, 2012 ... sion analysis were used to analyze the data obtained. ... interval: 0.39–1.06) there were no significant differences between the genotype ... of the M235T variant was high, it was not a significant risk factor for ... Before taking the measurement, the .... Distribution of the AGT M235T allele by gender in the.

Gene variants associated with antisocial behaviour: a latent variable approach.

Science.gov (United States)

Bentley, Mary Jane; Lin, Haiqun; Fernandez, Thomas V; Lee, Maria; Yrigollen, Carolyn M; Pakstis, Andrew J; Katsovich, Liliya; Olds, David L; Grigorenko, Elena L; Leckman, James F

2013-10-01

The aim of this study was to determine if a latent variable approach might be useful in identifying shared variance across genetic risk alleles that is associated with antisocial behaviour at age 15 years. Using a conventional latent variable approach, we derived an antisocial phenotype in 328 adolescents utilizing data from a 15-year follow-up of a randomized trial of a prenatal and infancy nurse-home visitation programme in Elmira, New York. We then investigated, via a novel latent variable approach, 450 informative genetic polymorphisms in 71 genes previously associated with antisocial behaviour, drug use, affiliative behaviours and stress response in 241 consenting individuals for whom DNA was available. Haplotype and Pathway analyses were also performed. Eight single-nucleotide polymorphisms (SNPs) from eight genes contributed to the latent genetic variable that in turn accounted for 16.0% of the variance within the latent antisocial phenotype. The number of risk alleles was linearly related to the latent antisocial variable scores. Haplotypes that included the putative risk alleles for all eight genes were also associated with higher latent antisocial variable scores. In addition, 33 SNPs from 63 of the remaining genes were also significant when added to the final model. Many of these genes interact on a molecular level, forming molecular networks. The results support a role for genes related to dopamine, norepinephrine, serotonin, glutamate, opioid and cholinergic signalling as well as stress response pathways in mediating susceptibility to antisocial behaviour. This preliminary study supports use of relevant behavioural indicators and latent variable approaches to study the potential 'co-action' of gene variants associated with antisocial behaviour. It also underscores the cumulative relevance of common genetic variants for understanding the aetiology of complex behaviour. If replicated in future studies, this approach may allow the identification of a

Missense variants in AIMP1 gene are implicated in autosomal recessive intellectual disability without neurodegeneration

NARCIS (Netherlands)

Iqbal, Z.; Puttmann, L.; Musante, L.; Razzaq, A.; Zahoor, M.Y.; Hu, H; Wienker, T.F.; Garshasbi, M.; Fattahi, Z.; Gilissen, C.; Vissers, L.E.; Brouwer, A.P. de; Veltman, J.A.; Pfundt, R.P.; Najmabadi, H.; Ropers, H.H.; Riazuddin, S.; Kahrizi, K.; Bokhoven, H. van

2016-01-01

AIMP1/p43 is a multifunctional non-catalytic component of the multisynthetase complex. The complex consists of nine catalytic and three non-catalytic proteins, which catalyze the ligation of amino acids to their cognate tRNA isoacceptors for use in protein translation. To date, two allelic variants

Efficient utilization of rare variants for detection of disease-related genomic regions.

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Lei Zhang

2010-12-01

Full Text Available When testing association between rare variants and diseases, an efficient analytical approach involves considering a set of variants in a genomic region as the unit of analysis. One factor complicating this approach is that the vast majority of rare variants in practical applications are believed to represent background neutral variation. As a result, analyzing a single set with all variants may not represent a powerful approach. Here, we propose two alternative strategies. In the first, we analyze the subsets of rare variants exhaustively. In the second, we categorize variants selectively into two subsets: one in which variants are overrepresented in cases, and the other in which variants are overrepresented in controls. When the proportion of neutral variants is moderate to large we show, by simulations, that the both proposed strategies improve the statistical power over methods analyzing a single set with total variants. When applied to a real sequencing association study, the proposed methods consistently produce smaller p-values than their competitors. When applied to another real sequencing dataset to study the difference of rare allele distributions between ethnic populations, the proposed methods detect the overrepresentation of variants between the CHB (Chinese Han in Beijing and YRI (Yoruba people of Ibadan populations with small p-values. Additional analyses suggest that there is no difference between the CHB and CHD (Chinese Han in Denver datasets, as expected. Finally, when applied to the CHB and JPT (Japanese people in Tokyo populations, existing methods fail to detect any difference, while it is detected by the proposed methods in several regions.

Social Cognition Deficits: The Key to Discriminate Behavioral Variant Frontotemporal Dementia from Alzheimer's Disease Regardless of Amnesia?

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Bertoux, Maxime; de Souza, Leonardo Cruz; O'Callaghan, Claire; Greve, Andrea; Sarazin, Marie; Dubois, Bruno; Hornberger, Michael

2016-01-01

Relative sparing of episodic memory is a diagnostic criterion of behavioral variant frontotemporal dementia (bvFTD). However, increasing evidence suggests that bvFTD patients can show episodic memory deficits at a similar level as Alzheimer's disease (AD). Social cognition tasks have been proposed to distinguish bvFTD, but no study to date has explored the utility of such tasks for the diagnosis of amnestic bvFTD. Here, we contrasted social cognition performance of amnestic and non-amnestic bvFTD from AD, with a subgroup having confirmed in vivo pathology markers. Ninety-six participants (38 bvFTD and 28 AD patients as well as 30 controls) performed the short Social-cognition and Emotional Assessment (mini-SEA). BvFTD patients were divided into amnestic versus non-amnestic presentation using the validated Free and Cued Selective Reminding Test (FCSRT) assessing episodic memory. As expected, the accuracy of the FCSRT to distinguish the overall bvFTD group from AD was low (69.7% ) with ∼50% of bvFTD patients being amnestic. By contrast, the diagnostic accuracy of the mini-SEA was high (87.9% ). When bvFTD patients were split on the level of amnesia, mini-SEA diagnostic accuracy remained high (85.1% ) for amnestic bvFTD versus AD and increased to very high (93.9% ) for non-amnestic bvFTD versus AD. Social cognition deficits can distinguish bvFTD and AD regardless of amnesia to a high degree and provide a simple way to distinguish both diseases at presentation. These findings have clear implications for the diagnostic criteria of bvFTD. They suggest that the emphasis should be on social cognition deficits with episodic memory deficits not being a helpful diagnostic criterion in bvFTD.

Calling genotypes from public RNA-sequencing data enables identification of genetic variants that affect gene-expression levels

NARCIS (Netherlands)

Deelen, Patrick; Zhernakova, Daria V.; de Haan, Mark; van der Sijde, Marijke; Bonder, Marc Jan; Karjalainen, Juha; van der Velde, K. Joeri; Abbott, Kristin M.; Fu, Jingyuan; Wijmenga, Cisca; Sinke, Richard J.; Swertz, Morris A.; Franke, Lude

2015-01-01

Background: RNA-sequencing (RNA-seq) is a powerful technique for the identification of genetic variants that affect gene-expression levels, either through expression quantitative trait locus (eQTL) mapping or through allele-specific expression (ASE) analysis. Given increasing numbers of RNA-seq

Allele coding in genomic evaluation

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Christensen Ole F

2011-06-01

Full Text Available Abstract Background Genomic data are used in animal breeding to assist genetic evaluation. Several models to estimate genomic breeding values have been studied. In general, two approaches have been used. One approach estimates the marker effects first and then, genomic breeding values are obtained by summing marker effects. In the second approach, genomic breeding values are estimated directly using an equivalent model with a genomic relationship matrix. Allele coding is the method chosen to assign values to the regression coefficients in the statistical model. A common allele coding is zero for the homozygous genotype of the first allele, one for the heterozygote, and two for the homozygous genotype for the other allele. Another common allele coding changes these regression coefficients by subtracting a value from each marker such that the mean of regression coefficients is zero within each marker. We call this centered allele coding. This study considered effects of different allele coding methods on inference. Both marker-based and equivalent models were considered, and restricted maximum likelihood and Bayesian methods were used in inference. Results Theoretical derivations showed that parameter estimates and estimated marker effects in marker-based models are the same irrespective of the allele coding, provided that the model has a fixed general mean. For the equivalent models, the same results hold, even though different allele coding methods lead to different genomic relationship matrices. Calculated genomic breeding values are independent of allele coding when the estimate of the general mean is included into the values. Reliabilities of estimated genomic breeding values calculated using elements of the inverse of the coefficient matrix depend on the allele coding because different allele coding methods imply different models. Finally, allele coding affects the mixing of Markov chain Monte Carlo algorithms, with the centered coding being

FTO variants are associated with obesity in the Chinese and Malay populations in Singapore.

Science.gov (United States)

Tan, Jonathan T; Dorajoo, Rajkumar; Seielstad, Mark; Sim, Xue Ling; Ong, Rick Twee-Hee; Chia, Kee Seng; Wong, Tien Yin; Saw, Seang Mei; Chew, Suok Kai; Aung, Tin; Tai, E-Shyong

2008-10-01

Association between genetic variants at the FTO locus and obesity has been consistently observed in populations of European ancestry and inconsistently in non-Europeans. The aim of this study was to examine the effects of FTO variants on obesity and type 2 diabetes in Southeast Asian populations. We examined associations between nine previously reported FTO single nucleotide polymorphisms (SNPs) with obesity, type 2 diabetes, and related traits in 4,298 participants (2,919 Chinese, 785 Malays, and 594 Asian Indians) from the 1998 Singapore National Health Survey (NHS98) and 2,996 Malays from the Singapore Malay Eye Study (SiMES). All nine SNPs exhibited strong linkage disequilibrium (r(2) = 0.6-0.99), and minor alleles were associated with obesity in the same direction as previous studies with effect sizes ranging from 0.42 to 0.68 kg/m(2) (P Chinese, 0.65 to 0.91 kg/m(2) (P Malays, and 0.52 to 0.64 kg/m(2) (P Malays after adjustment for age, sex, smoking, alcohol consumption, and exercise. The variants were also associated with type 2 diabetes, though not after adjustment for BMI (with the exception of the SiMES Malays: odds ratio 1.17-1.22; P Chinese and Malays in Singapore. Our data do not support the hypothesis that differences in allele frequency or genetic architecture underlie the lack of association observed in some populations of Asian ancestry. Examination of gene-environment interactions involving variants at this locus may provide further insights into the role of FTO in the pathogenesis of human obesity and diabetes.

Refining the impact of TCF7L2 gene variants on type 2 diabetes and adaptive evolution

DEFF Research Database (Denmark)

Helgason, Agnar; Pálsson, Snaebjörn; Thorleifsson, Gudmar

2007-01-01

diabetes risk variant, HapB(T2D), to the ancestral T allele of a SNP, rs7903146, through replication in West African and Danish type 2 diabetes case-control studies and an expanded Icelandic study. We also identify another variant of the same gene, HapA, that shows evidence of positive selection in East......We recently described an association between risk of type 2diabetes and variants in the transcription factor 7-like 2 gene (TCF7L2; formerly TCF4), with a population attributable risk (PAR) of 17%-28% in three populations of European ancestry. Here, we refine the definition of the TCF7L2 type 2...

Age- dependent effect of Alzheimer’s risk variant of CLU on EEG alpha rhythm in non-demented adults

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Natalya ePonomareva

2013-12-01

Full Text Available Polymorphism in the genomic region harboring the CLU gene (rs11136000 has been associated with the risk for Alzheimer’s disease (AD. CLU C allele is assumed to confer risk for AD and the allele T may have a protective effect.We investigated the influence of the AD-associated CLU genotype on a common neurophysiological trait of brain activity (resting-state alpha-rhythm activity in non-demented adults and elucidated whether this influence is modified over the course of aging. We examined quantitative EEG (qEEG in cohort of non-demented individuals (age range 20-80 divided into young (age range 20-50 and old (age range 51-80 cohorts and stratified by CLU polymorphism. To rule out the effect of the ApoE genotype on EEG characteristics, only subjects without the ApoE epsilon4 allele were included in the study.The homozygous presence of the AD risk variant CLU CC in non-demented subjects was associated with an increase of alpha3 absolute power. Moreover, the influence of CLU genotype on alpha3 was found to be higher in the subjects older than 50 years of age. The study also showed age-dependent alterations of alpha topographic distribution that occur independently of the CLU genotype.The increase of upper alpha power has been associated with hippocampal atrophy in patients with mild cognitive impairment (Moretti et al., 2012a. In our study, the CLU CC- dependent increase in upper alpha rhythm, particularly enhanced in elderly non-demented individuals, may imply that the genotype is related to preclinical dysregulation of hippocampal neurophysiology in aging and that this factor may contribute to pathogenesis of AD.

A common variant at the TERT-CLPTM1L locus is associated with estrogen receptor–negative breast cancer

Science.gov (United States)

Haiman, Christopher A; Chen, Gary K; Vachon, Celine M; Canzian, Federico; Dunning, Alison; Millikan, Robert C; Wang, Xianshu; Ademuyiwa, Foluso; Ahmed, Shahana; Ambrosone, Christine B; Baglietto, Laura; Balleine, Rosemary; Bandera, Elisa V; Beckmann, Matthias W; Berg, Christine D; Bernstein, Leslie; Blomqvist, Carl; Blot, William J; Brauch, Hiltrud; Buring, Julie E; Carey, Lisa A; Carpenter, Jane E; Chang-Claude, Jenny; Chanock, Stephen J; Chasman, Daniel I; Clarke, Christine L; Cox, Angela; Cross, Simon S; Deming, Sandra L; Diasio, Robert B; Dimopoulos, Athanasios M; Driver, W Ryan; Dünnebier, Thomas; Durcan, Lorraine; Eccles, Diana; Edlund, Christopher K; Ekici, Arif B; Fasching, Peter A; Feigelson, Heather S; Flesch-Janys, Dieter; Fostira, Florentia; Försti, Asta; Fountzilas, George; Gerty, Susan M; Giles, Graham G; Godwin, Andrew K; Goodfellow, Paul; Graham, Nikki; Greco, Dario; Hamann, Ute; Hankinson, Susan E; Hartmann, Arndt; Hein, Rebecca; Heinz, Judith; Holbrook, Andrea; Hoover, Robert N; Hu, Jennifer J; Hunter, David J; Ingles, Sue A; Irwanto, Astrid; Ivanovich, Jennifer; John, Esther M; Johnson, Nicola; Jukkola-Vuorinen, Arja; Kaaks, Rudolf; Ko, Yon-Dschun; Kolonel, Laurence N; Konstantopoulou, Irene; Kosma, Veli-Matti; Kulkarni, Swati; Lambrechts, Diether; Lee, Adam M; Le Marchand, Loïc; Lesnick, Timothy; Liu, Jianjun; Lindstrom, Sara; Mannermaa, Arto; Margolin, Sara; Martin, Nicholas G; Miron, Penelope; Montgomery, Grant W; Nevanlinna, Heli; Nickels, Stephan; Nyante, Sarah; Olswold, Curtis; Palmer, Julie; Pathak, Harsh; Pectasides, Dimitrios; Perou, Charles M; Peto, Julian; Pharoah, Paul D P; Pooler, Loreall C; Press, Michael F; Pylkäs, Katri; Rebbeck, Timothy R; Rodriguez-Gil, Jorge L; Rosenberg, Lynn; Ross, Eric; Rüdiger, Thomas; Silva, Isabel dos Santos; Sawyer, Elinor; Schmidt, Marjanka K; Schulz-Wendtland, Rüdiger; Schumacher, Fredrick; Severi, Gianluca; Sheng, Xin; Signorello, Lisa B; Sinn, Hans-Peter; Stevens, Kristen N; Southey, Melissa C; Tapper, William J; Tomlinson, Ian; Hogervorst, Frans B L; Wauters, Els; Weaver, JoEllen; Wildiers, Hans; Winqvist, Robert; Van Den Berg, David; Wan, Peggy; Xia, Lucy Y; Yannoukakos, Drakoulis; Zheng, Wei; Ziegler, Regina G; Siddiq, Afshan; Slager, Susan L; Stram, Daniel O; Easton, Douglas; Kraft, Peter; Henderson, Brian E; Couch, Fergus J

2012-01-01

Estrogen receptor (ER)-negative breast cancer shows a higher incidence in women of African ancestry compared to women of European ancestry. In search of common risk alleles for ER-negative breast cancer, we combined genome-wide association study (GWAS) data from women of African ancestry (1,004 ER-negative cases and 2,745 controls) and European ancestry (1,718 ER-negative cases and 3,670 controls), with replication testing conducted in an additional 2,292 ER-negative cases and 16,901 controls of European ancestry. We identified a common risk variant for ER-negative breast cancer at the TERT-CLPTM1L locus on chromosome 5p15 (rs10069690: per-allele odds ratio (OR) = 1.18 per allele, P = 1.0 × 10−10). The variant was also significantly associated with triple-negative (ER-negative, progesterone receptor (PR)-negative and human epidermal growth factor-2 (HER2)-negative) breast cancer (OR = 1.25, P = 1.1 × 10−9), particularly in younger women (<50 years of age) (OR = 1.48, P = 1.9 × 10−9). Our results identify a genetic locus associated with estrogen receptor negative breast cancer subtypes in multiple populations. PMID:22037553

A common variant at the TERT-CLPTM1L locus is associated with estrogen receptor-negative breast cancer.

Science.gov (United States)

Haiman, Christopher A; Chen, Gary K; Vachon, Celine M; Canzian, Federico; Dunning, Alison; Millikan, Robert C; Wang, Xianshu; Ademuyiwa, Foluso; Ahmed, Shahana; Ambrosone, Christine B; Baglietto, Laura; Balleine, Rosemary; Bandera, Elisa V; Beckmann, Matthias W; Berg, Christine D; Bernstein, Leslie; Blomqvist, Carl; Blot, William J; Brauch, Hiltrud; Buring, Julie E; Carey, Lisa A; Carpenter, Jane E; Chang-Claude, Jenny; Chanock, Stephen J; Chasman, Daniel I; Clarke, Christine L; Cox, Angela; Cross, Simon S; Deming, Sandra L; Diasio, Robert B; Dimopoulos, Athanasios M; Driver, W Ryan; Dünnebier, Thomas; Durcan, Lorraine; Eccles, Diana; Edlund, Christopher K; Ekici, Arif B; Fasching, Peter A; Feigelson, Heather S; Flesch-Janys, Dieter; Fostira, Florentia; Försti, Asta; Fountzilas, George; Gerty, Susan M; Giles, Graham G; Godwin, Andrew K; Goodfellow, Paul; Graham, Nikki; Greco, Dario; Hamann, Ute; Hankinson, Susan E; Hartmann, Arndt; Hein, Rebecca; Heinz, Judith; Holbrook, Andrea; Hoover, Robert N; Hu, Jennifer J; Hunter, David J; Ingles, Sue A; Irwanto, Astrid; Ivanovich, Jennifer; John, Esther M; Johnson, Nicola; Jukkola-Vuorinen, Arja; Kaaks, Rudolf; Ko, Yon-Dschun; Kolonel, Laurence N; Konstantopoulou, Irene; Kosma, Veli-Matti; Kulkarni, Swati; Lambrechts, Diether; Lee, Adam M; Marchand, Loïc Le; Lesnick, Timothy; Liu, Jianjun; Lindstrom, Sara; Mannermaa, Arto; Margolin, Sara; Martin, Nicholas G; Miron, Penelope; Montgomery, Grant W; Nevanlinna, Heli; Nickels, Stephan; Nyante, Sarah; Olswold, Curtis; Palmer, Julie; Pathak, Harsh; Pectasides, Dimitrios; Perou, Charles M; Peto, Julian; Pharoah, Paul D P; Pooler, Loreall C; Press, Michael F; Pylkäs, Katri; Rebbeck, Timothy R; Rodriguez-Gil, Jorge L; Rosenberg, Lynn; Ross, Eric; Rüdiger, Thomas; Silva, Isabel dos Santos; Sawyer, Elinor; Schmidt, Marjanka K; Schulz-Wendtland, Rüdiger; Schumacher, Fredrick; Severi, Gianluca; Sheng, Xin; Signorello, Lisa B; Sinn, Hans-Peter; Stevens, Kristen N; Southey, Melissa C; Tapper, William J; Tomlinson, Ian; Hogervorst, Frans B L; Wauters, Els; Weaver, JoEllen; Wildiers, Hans; Winqvist, Robert; Van Den Berg, David; Wan, Peggy; Xia, Lucy Y; Yannoukakos, Drakoulis; Zheng, Wei; Ziegler, Regina G; Siddiq, Afshan; Slager, Susan L; Stram, Daniel O; Easton, Douglas; Kraft, Peter; Henderson, Brian E; Couch, Fergus J

2011-10-30

Estrogen receptor (ER)-negative breast cancer shows a higher incidence in women of African ancestry compared to women of European ancestry. In search of common risk alleles for ER-negative breast cancer, we combined genome-wide association study (GWAS) data from women of African ancestry (1,004 ER-negative cases and 2,745 controls) and European ancestry (1,718 ER-negative cases and 3,670 controls), with replication testing conducted in an additional 2,292 ER-negative cases and 16,901 controls of European ancestry. We identified a common risk variant for ER-negative breast cancer at the TERT-CLPTM1L locus on chromosome 5p15 (rs10069690: per-allele odds ratio (OR) = 1.18 per allele, P = 1.0 × 10(-10)). The variant was also significantly associated with triple-negative (ER-negative, progesterone receptor (PR)-negative and human epidermal growth factor-2 (HER2)-negative) breast cancer (OR = 1.25, P = 1.1 × 10(-9)), particularly in younger women (<50 years of age) (OR = 1.48, P = 1.9 × 10(-9)). Our results identify a genetic locus associated with estrogen receptor negative breast cancer subtypes in multiple populations.

A recessive form of extreme macrocephaly and mild intellectual disability complements the spectrum of PTEN hamartoma tumour syndrome.

Science.gov (United States)

Schwerd, Tobias; Khaled, Andrea V; Schürmann, Manfred; Chen, Hannah; Händel, Norman; Reis, André; Gillessen-Kaesbach, Gabriele; Uhlig, Holm H; Abou Jamra, Rami

2016-06-01

PTEN hamartoma tumour syndrome (PHTS) is caused by heterozygous variants in PTEN and is characterised by tumour predisposition, macrocephaly, and cognition impairment. Bi-allelic loss of PTEN activity has not been reported so far and animal models suggest that bi-allelic loss of PTEN activity is embryonically lethal. Here, we report the identification of a novel homozygous variant in PTEN, NM_000314.4; c.545T>C; p.Leu182Ser, in two adolescent siblings with severe macrocephaly and mild intellectual disability. The variant is predicted to be damaging and is associated with significantly increased phospho-S6 downstream of PTEN. The absence of tumours in the two homozygous siblings as well as lack of symptoms of PHTS in the heterozygous carriers of the family suggest that this particular variant is functionally hypomorphic rather than deleterious.

The Val66Met Brain-Derived Neurotrophic Factor Gene Variant Interacts with Early Pain Exposure to Predict Cortisol Dysregulation in 7-year-old Children Born Very Preterm: Implications for Cognition

OpenAIRE

Chau, Cecil MY; Cepeda, Ivan L; Devlin, Angela M.; Weinberg, Joanne; Grunau, Ruth E

2015-01-01

Early stress in the form of repetitive neonatal pain, in infants born very preterm, is associated with long-term dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and with poorer cognitive performance. Brain-derived neurotrophic factor (BDNF) which is important in synaptic plasticity and cognitive functions is reduced by stress. Therefore the BDNF Val66Met variant, which affects secretion of BDNF, may interact with early exposure to pain-related stress in children born very prete...

Alleles of Ppd-D1 gene in the collection of Aegilops tauschii accessions and bread wheat varieties

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Babenko D. O.

2012-04-01

Full Text Available Light period significantly influences on the growth and development of plants. One of the major genes of photoperiod sensitivity is Ppd-D1, located on the chromosome 2D. The aim of the work was to determine the alleles and molecular structure of Ppd-D1 gene in samples from the collection of Ae. tauschii accessions, which have different flowering periods, and in 29 Ukrainian wheat varieties. Methods. We used methods of allele-specific PCR with primers to the Ppd-D1 gene, sequencing and Blast-analysis. Results. The collection of Ae. tauschii accessions and several varieties of winter and spring wheat was studied. The molecular structure of the allelic variants (414, 429 and 453 b. p. of Ppd-D1b gene was determined in the collection of Aegilops. tauschii accessions. Conclusions. The Ppd-D1a allele was present in all studied varieties of winter wheat. 60 % of spring wheat is characterized by Ppd-D1b allele (size of amplification products 414 b. p.. Blast-analysis of the sequence data banks on the basis of the reference sequence of sample k-1322 from the collection of Ae. tauschii accessions has shown a high homology (80 to 100 % between the nucleotide sequences of PRR genes, that characterize the A and D genomes of representatives of the genera Triticum and Aegilops.

Tyrosine receptor kinase B gene variants (NTRK2 variants) are associated with depressive disorders in temporal lobe epilepsy.

Science.gov (United States)

Torres, Carolina Machado; Siebert, Marina; Bock, Hugo; Mota, Suelen Mandelli; Castan, Juliana Unis; Scornavacca, Francisco; de Castro, Luiza Amaral; Saraiva-Pereira, Maria Luiza; Bianchin, Marino Muxfeldt

2017-06-01

Psychiatric comorbidities are highly prevalent in epilepsy, adding an important burden to the disease and profoundly affecting the quality of life of these individuals. Patients with temporal lobe epilepsy (TLE) are especially at risk to develop depression and several lines of evidence suggest that the association of depression with epilepsy might be related to common biological substrates. In this study, we test whether NTRK2 allele variants are associated with mood disorders or depressive disorders in patients with TLE. An association study of 163 patients with TLE. The NTRK2 variants studied were rs1867283, rs10868235, rs1147198, rs11140800, rs1187286, rs2289656, rs1624327, rs1443445, rs3780645, and rs2378672. All patients were submitted to the Structured Clinical Interview for DSM-IV (SCID) and epilepsy patients with mood disorders or depressive disorders were compared to epilepsy patients without mood disorders or depressive disorders. In our TLE cohort, 76 patients (46.6%) showed mood disorders. After logistic regression, independent risk factors for mood disorders in TLE were female sex, presence of concomitant anxiety disorders, and genetic variations in rs1867283 and rs10868235 NTRK2 variants. Depressive disorders accounted for this results and independent variables associated with depressive disorders in TLE were female sex (OR=2.59; 95%CI=1.15-5.82; p=0.021), presence of concomitant anxiety disorders (OR=3.72; 95%CI=1.71-8.06; p=0.001) or psychotic disorders (OR=3.86; 95%CI=1.12-13.25; p=0.032), A/A genotype in the rs1867283 NTRK2 gene (OR=3.06; 95%CI=1.25-7.50; p=0.015) and C/C genotype in the rs10868235 NTRK2 gene (OR=3.54; 1.55-8.08; p=0.003). Similarly, these genotypes also remained independently and significantly associated with depressive disorders when patients with depressive disorders were compared to TLE patients without any psychiatric comorbidity. In the present study, female sex, presence of concomitant anxiety or psychotic disorders, and

Distribution of the CCR5delta32 allele (gene variant CCR5) in Rondônia, Western Amazonian region, Brazil

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de Farias, Josileide Duarte; Santos, Marlene Guimarães; de França, Andonai Krauze; Delani, Daniel; Tada, Mauro Shugiro; Casseb, Almeida Andrade; Simões, Aguinaldo Luiz; Engracia, Vera

2012-01-01

Since around 1723, on the occasion of its initial colonization by Europeans, Rondonia has received successive waves of immigrants. This has been further swelled by individuals from northeastern Brazil, who began entering at the beginning of the twentieth century. The ethnic composition varies across the state according to the various sites of settlement of each wave of immigrants. We analyzed the frequency of the CCR5Δ32 allele of the CCR5 chemokine receptor, which is considered a Caucasian marker, in five sample sets from the population. Four were collected in Porto Velho, the state capital and the site of several waves of migration. Of these, two, from the Hospital de Base were comprised of HB Mothers and HB Newborns presenting allele frequencies of 3.5% and 3.1%, respectively, a third from the peri-urban neighborhoods of Candelária/Bate-Estaca (1.8%), whereas a fourth, from the Research Center on Tropical Medicine/CEPEM (0.6%), was composed of malaria patients under treament. The fifth sample (3.4%) came from the inland Quilombola village of Pedras Negras. Two homozygous individuals (CCR5Δ32/CCR5Δ32) were detected among the HB Mother samples. The frequency of this allele was heterogeneous and higher where the European inflow was more pronounced. The presence of the allele in Pedras Negras revealed European miscegenation in a community largely comprising Quilombolas. PMID:22481870

Common Low-Density Lipoprotein Receptor p.G116S Variant Has a Large Effect on Plasma Low-Density Lipoprotein Cholesterol in Circumpolar Inuit Populations

DEFF Research Database (Denmark)

Dube, J. B.; Wang, J.; Cao, H.

2015-01-01

.G116S and p.R730W. METHODS AND RESULTS: Genotyping these variants in 3324 Inuit from Alaska, Canada, and Greenland showed they were common, with allele frequencies 10% to 15%. Only p.G116S was associated with dyslipidemia: the increase in LDL cholesterol was 0.54 mmol/L (20.9 mg/dL) per allele (P=5.6x...

[Cloning and sequencing of KIR2DL1 framework gene cDNA and identification of a novel allele].

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Sun, Ge; Wang, Chang; Zhen, Jianxin; Zhang, Guobin; Xu, Yunping; Deng, Zhihui

2016-10-01

To develop an assay for cDNA cloning and haplotype sequencing of KIR2DL1 framework gene and determine the genotype of an ethnic Han from southern China. Total RNA was isolated from peripheral blood sample, and complementary DNA (cDNA) transcript was synthesized by RT-PCR. The entire coding sequence of the KIR2DL1 framework gene was amplified with a pair of KIR2DL1-specific PCR primers. The PCR products with a length of approximately 1.2 kb were then subjected to cloning and haplotype sequencing. A specific target fragment of the KIR2DL1 framework gene was obtained. Following allele separation, a wild-type KIR2DL1*00302 allele and a novel variant allele, KIR2DL1*031, were identified. Sequence alignment with KIR2DL1 alleles from the IPD-KIR Database showed that the novel allele KIR2DL1*031 has differed from the closest allele KIR2DL1*00302 by a non-synonymous mutation at CDS nt 188A>G (codon 42 GAG>GGG) in exon 4, which has caused an amino acid change Glu42Gly. The sequence of the novel allele KIR2DL1*031 was submitted to GenBank under the accession number KP025960 and to the IPD-KIR Database under the submission number IWS40001982. A name KIR2DL1*031 has been officially assigned by the World Health Organization (WHO) Nomenclature Committee. An assay for cDNA cloning and haplotype sequencing of KIR2DL1 has been established, which has a broad applications in KIR studies at allelic level.

Meta-analyses of HFE variants in coronary heart disease.

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Lian, Jiangfang; Xu, Limin; Huang, Yi; Le, Yanping; Jiang, Danjie; Yang, Xi; Xu, Weifeng; Huang, Xiaoyan; Dong, Changzheng; Ye, Meng; Zhou, Jianqing; Duan, Shiwei

2013-09-15

HFE gene variants can cause hereditary hemochromatosis (HH) that often comes along with an increased risk of coronary heart disease (CHD). The goal of our study is to assess the contribution of four HFE gene variants to the risk of CHD. We conducted four meta-analyses of the studies examining the association between four HFE gene variants and the risk of CHD. A systematic search was conducted using MEDLINE, EMBASE, Web of Science and China National Knowledge Infrastructure (CNKI), Wanfang Chinese Periodical. Meta-analyses showed that HFE rs1799945-G allele was associated with a 6% increased risk of CHD (P=0.02, odds ratio (OR)=1.06, 95% confidence interval (CI)=1.01-1.11). However, no association between the other three HFE gene variants (rs1800562, rs1800730, and rs9366637) and CHD risk was observed by the meta-analyses (all P values>0.05). In addition, the results of our case-control study indicated that rs1800562 and rs1800730 were monomorphic, and that rs1799945 and rs9366637 were not associated with CHD in Han Chinese. Our meta-analysis suggested that a significant association existed between rs1799945 mutation and CHD, although this mutation was rare in Han Chinese. Copyright © 2013 Elsevier B.V. All rights reserved.

Common variants of the TCF7L2 gene are associated with increased risk of type 2 diabetes mellitus in a UK-resident South Asian population

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Kumar Sudhesh

2008-02-01

Full Text Available Abstract Background Recent studies have implicated variants of the transcription factor 7-like 2 (TCF7L2 gene in genetic susceptibility to type 2 diabetes mellitus in several different populations. The aim of this study was to determine whether variants of this gene are also risk factors for type 2 diabetes development in a UK-resident South Asian cohort of Punjabi ancestry. Methods We genotyped four single nucleotide polymorphisms (SNPs of TCF7L2 (rs7901695, rs7903146, rs11196205 and rs12255372 in 831 subjects with diabetes and 437 control subjects. Results The minor allele of each variant was significantly associated with type 2 diabetes; the greatest risk of developing the disease was conferred by rs7903146, with an allelic odds ratio (OR of 1.31 (95% CI: 1.11 – 1.56, p = 1.96 × 10-3. For each variant, disease risk associated with homozygosity for the minor allele was greater than that for heterozygotes, with the exception of rs12255372. To determine the effect on the observed associations of including young control subjects in our data set, we reanalysed the data using subsets of the control group defined by different minimum age thresholds. Increasing the minimum age of our control subjects resulted in a corresponding increase in OR for all variants of the gene (p ≤ 1.04 × 10-7. Conclusion Our results support recent findings that TCF7L2 is an important genetic risk factor for the development of type 2 diabetes in multiple ethnic groups.

Multivariate analysis of dopaminergic gene variants as risk factors of heroin dependence.

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Andrea Vereczkei

Full Text Available BACKGROUND: Heroin dependence is a debilitating psychiatric disorder with complex inheritance. Since the dopaminergic system has a key role in rewarding mechanism of the brain, which is directly or indirectly targeted by most drugs of abuse, we focus on the effects and interactions among dopaminergic gene variants. OBJECTIVE: To study the potential association between allelic variants of dopamine D2 receptor (DRD2, ANKK1 (ankyrin repeat and kinase domain containing 1, dopamine D4 receptor (DRD4, catechol-O-methyl transferase (COMT and dopamine transporter (SLC6A3 genes and heroin dependence in Hungarian patients. METHODS: 303 heroin dependent subjects and 555 healthy controls were genotyped for 7 single nucleotide polymorphisms (SNPs rs4680 of the COMT gene; rs1079597 and rs1800498 of the DRD2 gene; rs1800497 of the ANKK1 gene; rs1800955, rs936462 and rs747302 of the DRD4 gene. Four variable number of tandem repeats (VNTRs were also genotyped: 120 bp duplication and 48 bp VNTR in exon 3 of DRD4 and 40 bp VNTR and intron 8 VNTR of SLC6A3. We also perform a multivariate analysis of associations using Bayesian networks in Bayesian multilevel analysis (BN-BMLA. FINDINGS AND CONCLUSIONS: In single marker analysis the TaqIA (rs1800497 and TaqIB (rs1079597 variants were associated with heroin dependence. Moreover, -521 C/T SNP (rs1800955 of the DRD4 gene showed nominal association with a possible protective effect of the C allele. After applying the Bonferroni correction TaqIB was still significant suggesting that the minor (A allele of the TaqIB SNP is a risk component in the genetic background of heroin dependence. The findings of the additional multiple marker analysis are consistent with the results of the single marker analysis, but this method was able to reveal an indirect effect of a promoter polymorphism (rs936462 of the DRD4 gene and this effect is mediated through the -521 C/T (rs1800955 polymorphism in the promoter.

Fine-scale mapping of the 5q11.2 breast cancer locus reveals at least three independent risk variants regulating MAP3K1

DEFF Research Database (Denmark)

Glubb, Dylan M; Maranian, Mel J; Michailidou, Kyriaki

2015-01-01

evidence of association of a further 173 variants (iCHAV2) containing three subsets with a range of effects (the strongest was rs113317823 [pcond = 1.61 × 10(-5)]) and five variants composing iCHAV3 (lead rs11949391; ER(+): OR = 0.90, 95% CI = 0.87-0.93, pcond = 1.4 × 10(-4)). Twenty-six percent......CHAV2a], and rs17432750 [iCHAV3]) increased MAP3K1 transcriptional activity. Chromatin immunoprecipitation analysis revealed diminished GATA3 binding to the minor (cancer-protective) allele of rs17432750, indicating a mechanism for its action. We propose that the cancer risk alleles act to increase MAP3...

A genome-wide scan for common alleles affecting risk for autism.

LENUS (Irish Health Repository)

Anney, Richard

2010-10-15

Although autism spectrum disorders (ASDs) have a substantial genetic basis, most of the known genetic risk has been traced to rare variants, principally copy number variants (CNVs). To identify common risk variation, the Autism Genome Project (AGP) Consortium genotyped 1558 rigorously defined ASD families for 1 million single-nucleotide polymorphisms (SNPs) and analyzed these SNP genotypes for association with ASD. In one of four primary association analyses, the association signal for marker rs4141463, located within MACROD2, crossed the genome-wide association significance threshold of P < 5 × 10(-8). When a smaller replication sample was analyzed, the risk allele at rs4141463 was again over-transmitted; yet, consistent with the winner\\'s curse, its effect size in the replication sample was much smaller; and, for the combined samples, the association signal barely fell below the P < 5 × 10(-8) threshold. Exploratory analyses of phenotypic subtypes yielded no significant associations after correction for multiple testing. They did, however, yield strong signals within several genes, KIAA0564, PLD5, POU6F2, ST8SIA2 and TAF1C.

A genome-wide scan for common alleles affecting risk for autism.

Science.gov (United States)

Anney, Richard; Klei, Lambertus; Pinto, Dalila; Regan, Regina; Conroy, Judith; Magalhaes, Tiago R; Correia, Catarina; Abrahams, Brett S; Sykes, Nuala; Pagnamenta, Alistair T; Almeida, Joana; Bacchelli, Elena; Bailey, Anthony J; Baird, Gillian; Battaglia, Agatino; Berney, Tom; Bolshakova, Nadia; Bölte, Sven; Bolton, Patrick F; Bourgeron, Thomas; Brennan, Sean; Brian, Jessica; Carson, Andrew R; Casallo, Guillermo; Casey, Jillian; Chu, Su H; Cochrane, Lynne; Corsello, Christina; Crawford, Emily L; Crossett, Andrew; Dawson, Geraldine; de Jonge, Maretha; Delorme, Richard; Drmic, Irene; Duketis, Eftichia; Duque, Frederico; Estes, Annette; Farrar, Penny; Fernandez, Bridget A; Folstein, Susan E; Fombonne, Eric; Freitag, Christine M; Gilbert, John; Gillberg, Christopher; Glessner, Joseph T; Goldberg, Jeremy; Green, Jonathan; Guter, Stephen J; Hakonarson, Hakon; Heron, Elizabeth A; Hill, Matthew; Holt, Richard; Howe, Jennifer L; Hughes, Gillian; Hus, Vanessa; Igliozzi, Roberta; Kim, Cecilia; Klauck, Sabine M; Kolevzon, Alexander; Korvatska, Olena; Kustanovich, Vlad; Lajonchere, Clara M; Lamb, Janine A; Laskawiec, Magdalena; Leboyer, Marion; Le Couteur, Ann; Leventhal, Bennett L; Lionel, Anath C; Liu, Xiao-Qing; Lord, Catherine; Lotspeich, Linda; Lund, Sabata C; Maestrini, Elena; Mahoney, William; Mantoulan, Carine; Marshall, Christian R; McConachie, Helen; McDougle, Christopher J; McGrath, Jane; McMahon, William M; Melhem, Nadine M; Merikangas, Alison; Migita, Ohsuke; Minshew, Nancy J; Mirza, Ghazala K; Munson, Jeff; Nelson, Stanley F; Noakes, Carolyn; Noor, Abdul; Nygren, Gudrun; Oliveira, Guiomar; Papanikolaou, Katerina; Parr, Jeremy R; Parrini, Barbara; Paton, Tara; Pickles, Andrew; Piven, Joseph; Posey, David J; Poustka, Annemarie; Poustka, Fritz; Prasad, Aparna; Ragoussis, Jiannis; Renshaw, Katy; Rickaby, Jessica; Roberts, Wendy; Roeder, Kathryn; Roge, Bernadette; Rutter, Michael L; Bierut, Laura J; Rice, John P; Salt, Jeff; Sansom, Katherine; Sato, Daisuke; Segurado, Ricardo; Senman, Lili; Shah, Naisha; Sheffield, Val C; Soorya, Latha; Sousa, Inês; Stoppioni, Vera; Strawbridge, Christina; Tancredi, Raffaella; Tansey, Katherine; Thiruvahindrapduram, Bhooma; Thompson, Ann P; Thomson, Susanne; Tryfon, Ana; Tsiantis, John; Van Engeland, Herman; Vincent, John B; Volkmar, Fred; Wallace, Simon; Wang, Kai; Wang, Zhouzhi; Wassink, Thomas H; Wing, Kirsty; Wittemeyer, Kerstin; Wood, Shawn; Yaspan, Brian L; Zurawiecki, Danielle; Zwaigenbaum, Lonnie; Betancur, Catalina; Buxbaum, Joseph D; Cantor, Rita M; Cook, Edwin H; Coon, Hilary; Cuccaro, Michael L; Gallagher, Louise; Geschwind, Daniel H; Gill, Michael; Haines, Jonathan L; Miller, Judith; Monaco, Anthony P; Nurnberger, John I; Paterson, Andrew D; Pericak-Vance, Margaret A; Schellenberg, Gerard D; Scherer, Stephen W; Sutcliffe, James S; Szatmari, Peter; Vicente, Astrid M; Vieland, Veronica J; Wijsman, Ellen M; Devlin, Bernie; Ennis, Sean; Hallmayer, Joachim

2010-10-15

Although autism spectrum disorders (ASDs) have a substantial genetic basis, most of the known genetic risk has been traced to rare variants, principally copy number variants (CNVs). To identify common risk variation, the Autism Genome Project (AGP) Consortium genotyped 1558 rigorously defined ASD families for 1 million single-nucleotide polymorphisms (SNPs) and analyzed these SNP genotypes for association with ASD. In one of four primary association analyses, the association signal for marker rs4141463, located within MACROD2, crossed the genome-wide association significance threshold of P < 5 × 10(-8). When a smaller replication sample was analyzed, the risk allele at rs4141463 was again over-transmitted; yet, consistent with the winner's curse, its effect size in the replication sample was much smaller; and, for the combined samples, the association signal barely fell below the P < 5 × 10(-8) threshold. Exploratory analyses of phenotypic subtypes yielded no significant associations after correction for multiple testing. They did, however, yield strong signals within several genes, KIAA0564, PLD5, POU6F2, ST8SIA2 and TAF1C.

Fine-scale patterns of population stratification confound rare variant association tests.

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Timothy D O'Connor

Full Text Available Advances in next-generation sequencing technology have enabled systematic exploration of the contribution of rare variation to Mendelian and complex diseases. Although it is well known that population stratification can generate spurious associations with common alleles, its impact on rare variant association methods remains poorly understood. Here, we performed exhaustive coalescent simulations with demographic parameters calibrated from exome sequence data to evaluate the performance of nine rare variant association methods in the presence of fine-scale population structure. We find that all methods have an inflated spurious association rate for parameter values that are consistent with levels of differentiation typical of European populations. For example, at a nominal significance level of 5%, some test statistics have a spurious association rate as high as 40%. Finally, we empirically assess the impact of population stratification in a large data set of 4,298 European American exomes. Our results have important implications for the design, analysis, and interpretation of rare variant genome-wide association studies.

Identification of a regulatory variant that binds FOXA1 and FOXA2 at the CDC123/CAMK1D type 2 diabetes GWAS locus.

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Marie P Fogarty

2014-09-01

Full Text Available Many of the type 2 diabetes loci identified through genome-wide association studies localize to non-protein-coding intronic and intergenic regions and likely contain variants that regulate gene transcription. The CDC123/CAMK1D type 2 diabetes association signal on chromosome 10 spans an intergenic region between CDC123 and CAMK1D and also overlaps the CDC123 3'UTR. To gain insight into the molecular mechanisms underlying the association signal, we used open chromatin, histone modifications and transcription factor ChIP-seq data sets from type 2 diabetes-relevant cell types to identify SNPs overlapping predicted regulatory regions. Two regions containing type 2 diabetes-associated variants were tested for enhancer activity using luciferase reporter assays. One SNP, rs11257655, displayed allelic differences in transcriptional enhancer activity in 832/13 and MIN6 insulinoma cells as well as in human HepG2 hepatocellular carcinoma cells. The rs11257655 risk allele T showed greater transcriptional activity than the non-risk allele C in all cell types tested. Using electromobility shift and supershift assays we demonstrated that the rs11257655 risk allele showed allele-specific binding to FOXA1 and FOXA2. We validated FOXA1 and FOXA2 enrichment at the rs11257655 risk allele using allele-specific ChIP in human islets. These results suggest that rs11257655 affects transcriptional activity through altered binding of a protein complex that includes FOXA1 and FOXA2, providing a potential molecular mechanism at this GWAS locus.

Local exome sequences facilitate imputation of less common variants and increase power of genome wide association studies.

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Peter K Joshi

Full Text Available The analysis of less common variants in genome-wide association studies promises to elucidate complex trait genetics but is hampered by low power to reliably detect association. We show that addition of population-specific exome sequence data to global reference data allows more accurate imputation, particularly of less common SNPs (minor allele frequency 1-10% in two very different European populations. The imputation improvement corresponds to an increase in effective sample size of 28-38%, for SNPs with a minor allele frequency in the range 1-3%.

Allele-specific gene expression in a wild nonhuman primate population

Science.gov (United States)

Tung, J.; Akinyi, M. Y.; Mutura, S.; Altmann, J.; Wray, G. A.; Alberts, S. C.

2015-01-01

Natural populations hold enormous potential for evolutionary genetic studies, especially when phenotypic, genetic and environmental data are all available on the same individuals. However, untangling the genotype-phenotype relationship in natural populations remains a major challenge. Here, we describe results of an investigation of one class of phenotype, allele-specific gene expression (ASGE), in the well-studied natural population of baboons of the Amboseli basin, Kenya. ASGE measurements identify cases in which one allele of a gene is overexpressed relative to the alternative allele of the same gene, within individuals, thus providing a control for background genetic and environmental effects. Here, we characterize the incidence of ASGE in the Amboseli baboon population, focusing on the genetic and environmental contributions to ASGE in a set of eleven genes involved in immunity and defence. Within this set, we identify evidence for common ASGE in four genes. We also present examples of two relationships between cis-regulatory genetic variants and the ASGE phenotype. Finally, we identify one case in which this relationship is influenced by a novel gene-environment interaction. Specifically, the dominance rank of an individual’s mother during its early life (an aspect of that individual’s social environment) influences the expression of the gene CCL5 via an interaction with cis-regulatory genetic variation. These results illustrate how environmental and ecological data can be integrated into evolutionary genetic studies of functional variation in natural populations. They also highlight the potential importance of early life environmental variation in shaping the genetic architecture of complex traits in wild mammals. PMID:21226779

Simultaneous SNP identification and assessment of allele-specific bias from ChIP-seq data

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Ni Yunyun

2012-09-01

Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs have been associated with many aspects of human development and disease, and many non-coding SNPs associated with disease risk are presumed to affect gene regulation. We have previously shown that SNPs within transcription factor binding sites can affect transcription factor binding in an allele-specific and heritable manner. However, such analysis has relied on prior whole-genome genotypes provided by large external projects such as HapMap and the 1000 Genomes Project. This requirement limits the study of allele-specific effects of SNPs in primary patient samples from diseases of interest, where complete genotypes are not readily available. Results In this study, we show that we are able to identify SNPs de novo and accurately from ChIP-seq data generated in the ENCODE Project. Our de novo identified SNPs from ChIP-seq data are highly concordant with published genotypes. Independent experimental verification of more than 100 sites estimates our false discovery rate at less than 5%. Analysis of transcription factor binding at de novo identified SNPs revealed widespread heritable allele-specific binding, confirming previous observations. SNPs identified from ChIP-seq datasets were significantly enriched for disease-associated variants, and we identified dozens of allele-specific binding events in non-coding regions that could distinguish between disease and normal haplotypes. Conclusions Our approach combines SNP discovery, genotyping and allele-specific analysis, but is selectively focused on functional regulatory elements occupied by transcription factors or epigenetic marks, and will therefore be valuable for identifying the functional regulatory consequences of non-coding SNPs in primary disease samples.

Variants in DENND1A are associated with polycystic ovary syndrome in women of European ancestry.

Science.gov (United States)

Welt, Corrine K; Styrkarsdottir, Unnur; Ehrmann, David A; Thorleifsson, Gudmar; Arason, Gudmundur; Gudmundsson, Jens A; Ober, Carole; Rosenfield, Robert L; Saxena, Richa; Thorsteinsdottir, Unnur; Crowley, William F; Stefansson, Kari

2012-07-01

A genome-wide association study has identified three loci (five independent signals) that confer risk for polycystic ovary syndrome (PCOS) in Han Chinese women. Replication is necessary to determine whether the same variants confer risk for PCOS in women of European ancestry. The objective of the study was to test whether these PCOS risk variants in Han Chinese women confer risk for PCOS in women of European ancestry. This was a case-control study. The study was conducted at deCODE Genetics in Iceland and two academic medical centers in the United States. Cases were 376 Icelandic women and 565 and 203 women from Boston, MA, and Chicago, IL, respectively, all diagnosed with PCOS by the National Institutes of Health criteria. Controls were 16,947, 483, and 189 women not known to have PCOS from Iceland, Boston, and Chicago, respectively. There were no interventions. Main outcomes were allele frequencies for seven variants in PCOS cases and controls. Two strongly correlated Han Chinese PCOS risk variants on chromosome 9q33.3, rs10986105[C], and rs10818854[A], were replicated in samples of European ancestry with odds ratio of 1.68 (P = 0.00033) and odds ratio of 1.53 (P = 0.0019), respectively. Other risk variants at 2p16.3 (rs13405728), 2p21 (rs12468394, rs12478601, and rs13429458), and 9q33.3 (rs2479106), or variants correlated with them, did not associate with PCOS. The same allele of rs10986105 that increased the risk of PCOS also increased the risk of hyperandrogenism in women without PCOS from Iceland and demonstrated a stronger risk for PCOS defined by the National Institutes of Health criteria than the Rotterdam criteria. We replicated one of the five Chinese PCOS association signals, represented by rs10986105 and rs10818854 on 9q33, in individuals of European ancestry. Examination of the subjects meeting at least one of the Rotterdam criteria for PCOS suggests that the variant may be involved in the hyperandrogenism and possibly the irregular menses of PCOS.

Case-control study for colorectal cancer genetic susceptibility in EPICOLON: previously identified variants and mucins

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Moreno Victor

2011-08-01

Full Text Available Abstract Background Colorectal cancer (CRC is the second leading cause of cancer death in developed countries. Familial aggregation in CRC is also important outside syndromic forms and, in this case, a polygenic model with several common low-penetrance alleles contributing to CRC genetic predisposition could be hypothesized. Mucins and GALNTs (N-acetylgalactosaminyltransferase are interesting candidates for CRC genetic susceptibility and have not been previously evaluated. We present results for ten genetic variants linked to CRC risk in previous studies (previously identified category and 18 selected variants from the mucin gene family in a case-control association study from the Spanish EPICOLON consortium. Methods CRC cases and matched controls were from EPICOLON, a prospective, multicenter, nationwide Spanish initiative, comprised of two independent stages. Stage 1 corresponded to 515 CRC cases and 515 controls, whereas stage 2 consisted of 901 CRC cases and 909 controls. Also, an independent cohort of 549 CRC cases and 599 controls outside EPICOLON was available for additional replication. Genotyping was performed for ten previously identified SNPs in ADH1C, APC, CCDN1, IL6, IL8, IRS1, MTHFR, PPARG, VDR and ARL11, and 18 selected variants in the mucin gene family. Results None of the 28 SNPs analyzed in our study was found to be associated with CRC risk. Although four SNPs were significant with a P-value ADH1C (OR = 1.63, 95% CI = 1.06-2.50, P-value = 0.02, recessive, rs1800795 in IL6 (OR = 1.62, 95% CI = 1.10-2.37, P-value = 0.01, recessive, rs3803185 in ARL11 (OR = 1.58, 95% CI = 1.17-2.15, P-value = 0.007, codominant, and rs2102302 in GALNTL2 (OR = 1.20, 95% CI = 1.00-1.44, P-value = 0.04, log-additive 0, 1, 2 alleles], only rs3803185 achieved statistical significance in EPICOLON stage 2 (OR = 1.34, 95% CI = 1.06-1.69, P-value = 0.01, recessive. In the joint analysis for both stages, results were only significant for rs3803185 (OR = 1

Case-control study for colorectal cancer genetic susceptibility in EPICOLON: previously identified variants and mucins

International Nuclear Information System (INIS)

Abulí, Anna; Morillas, Juan D; Rigau, Joaquim; Latorre, Mercedes; Fernández-Bañares, Fernando; Peña, Elena; Riestra, Sabino; Payá, Artemio; Jover, Rodrigo; Xicola, Rosa M; Llor, Xavier; Fernández-Rozadilla, Ceres; Carvajal-Carmona, Luis; Villanueva, Cristina M; Moreno, Victor; Piqué, Josep M; Carracedo, Angel; Castells, Antoni; Andreu, Montserrat; Ruiz-Ponte, Clara; Castellví-Bel, Sergi; Alonso-Espinaco, Virginia; Muñoz, Jenifer; Gonzalo, Victoria; Bessa, Xavier; González, Dolors; Clofent, Joan; Cubiella, Joaquin

2011-01-01

Colorectal cancer (CRC) is the second leading cause of cancer death in developed countries. Familial aggregation in CRC is also important outside syndromic forms and, in this case, a polygenic model with several common low-penetrance alleles contributing to CRC genetic predisposition could be hypothesized. Mucins and GALNTs (N-acetylgalactosaminyltransferase) are interesting candidates for CRC genetic susceptibility and have not been previously evaluated. We present results for ten genetic variants linked to CRC risk in previous studies (previously identified category) and 18 selected variants from the mucin gene family in a case-control association study from the Spanish EPICOLON consortium. CRC cases and matched controls were from EPICOLON, a prospective, multicenter, nationwide Spanish initiative, comprised of two independent stages. Stage 1 corresponded to 515 CRC cases and 515 controls, whereas stage 2 consisted of 901 CRC cases and 909 controls. Also, an independent cohort of 549 CRC cases and 599 controls outside EPICOLON was available for additional replication. Genotyping was performed for ten previously identified SNPs in ADH1C, APC, CCDN1, IL6, IL8, IRS1, MTHFR, PPARG, VDR and ARL11, and 18 selected variants in the mucin gene family. None of the 28 SNPs analyzed in our study was found to be associated with CRC risk. Although four SNPs were significant with a P-value < 0.05 in EPICOLON stage 1 [rs698 in ADH1C (OR = 1.63, 95% CI = 1.06-2.50, P-value = 0.02, recessive), rs1800795 in IL6 (OR = 1.62, 95% CI = 1.10-2.37, P-value = 0.01, recessive), rs3803185 in ARL11 (OR = 1.58, 95% CI = 1.17-2.15, P-value = 0.007, codominant), and rs2102302 in GALNTL2 (OR = 1.20, 95% CI = 1.00-1.44, P-value = 0.04, log-additive 0, 1, 2 alleles], only rs3803185 achieved statistical significance in EPICOLON stage 2 (OR = 1.34, 95% CI = 1.06-1.69, P-value = 0.01, recessive). In the joint analysis for both stages, results were only significant for rs3803185 (OR = 1.12, 95% CI = 1

Genetic variant SLC2A2 [corrected] Is associated with risk of cardiovascular disease – assessing the individual and cumulative effect of 46 type 2 diabetes related genetic variants.

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Anders Borglykke

Full Text Available To assess the individual and combined effect of 46 type 2 diabetes related risk alleles on incidence of a composite CVD endpoint.Data from the first Danish MONICA study (N = 3523 and the Inter99 study (N = 6049 was used. Using Cox proportional hazard regression the individual effect of each risk allele on incident CVD was analyzed. Risk was presented as hazard ratios (HR per risk allele.During 80,859 person years 1441 incident cases of CVD (fatal and non-fatal occurred in the MONICA study. In Inter99 942 incident cases were observed during 61,239 person years. In the Danish MONICA study four gene variants were significantly associated with incident CVD independently of known diabetes status at baseline; SLC2A2 rs11920090 (HR 1.147, 95% CI 1.027-1.283 , P = 0.0154, C2CD4A rs7172432 (1.112, 1.027-1.205 , P = 0.0089, GCKR rs780094 (1.094, 1.007-1.188 , P = 0.0335 and C2CD4B rs11071657 (1.092, 1.007-1.183 , P = 0.0323. The genetic score was significantly associated with increased risk of CVD (1.025, 1.010-1.041, P = 0.0016. In Inter99 two gene variants were associated with risk of CVD independently of diabetes; SLC2A2 (HR 1.180, 95% CI 1.038-1.341 P = 0.0116 and FTO (0.909, 0.827-0.998, P = 0.0463. Analysing the two populations together we found SLC2A2 rs11920090 (HR 1.164, 95% CI 1.070-1.267, P = 0.0004 meeting the Bonferroni corrected threshold for significance. GCKR rs780094 (1.076, 1.010-1.146, P = 0.0229, C2CD4B rs11071657 (1.067, 1.003-1.135, P = 0.0385 and NOTCH2 rs10923931 (1.104 (1.001 ; 1.217 , P = 0.0481 were found associated with CVD without meeting the corrected threshold. The genetic score was significantly associated with increased risk of CVD (1.018, 1.006-1.031, P = 0.0043.This study showed that out of the 46 genetic variants examined only the minor risk allele of SLC2A2 rs11920090 was significantly (P = 0.0005 associated with a composite endpoint of incident CVD below the threshold for statistical significance corrected for

Cerivastatin, Genetic Variants, and the Risk of Rhabdomyolysis

Science.gov (United States)

Marciante, Kristin D.; Durda, Jon P.; Heckbert, Susan R.; Lumley, Thomas; Rice, Ken; McKnight, Barbara; Totah, Rheem A.; Tamraz, Bani; Kroetz, Deanna L.; Fukushima, Hisayo; Kaspera, Rüdiger; Bis, Joshua C.; Glazer, Nicole L.; Li, Guo; Austin, Thomas R.; Taylor, Kent D.; Rotter, Jerome I.; Jaquish, Cashell E.; Kwok, Pui-Yan; Tracy, Russell P.; Psaty, Bruce M.

2011-01-01

Objective The withdrawal of cerivastatin involved an uncommon but serious adverse reaction, rhabdomyolysis. The bimodal response--rhabdomyolysis in a small proportion of users-- points to genetic factors as a potential cause. We conducted a case-control study to evaluate genetic markers for cerivastatin-associated rhabdomyolysis. Methods The study had two components: a candidate gene study to evaluate variants in CYP2C8, UGT1A1, UGT1A3, and SLCO1B1; and a genome-wide association (GWA) study to identify risk factors in other regions of the genome. 185 rhabdomyolysis cases were frequency matched to statin-using controls from the Cardiovascular Health Study (n=374) and the Heart and Vascular Health Study (n=358). Validation relied on functional studies. Results Permutation test results suggested an association between cerivastatin-associated rhabdomyolysis and variants in SLCO1B1 (p = 0.002), but not variants in CYP2C8 (p = 0.073) or the UGTs (p = 0.523). An additional copy of the minor allele of SLCO1B1 rs4149056 (p.Val174Ala) was associated with the risk of rhabdomyolysis (OR: 1.89, 95% CI: 1.40 to 2.56). In transfected cells, this variant reduced cerivastatin transport by 40% compared with the reference transporter (p rhabdomyolysis (OR: 0.48; 95% CI: 0.36 to 0.63). Conclusion We identified modest genetic risk factors for an extreme response to cerivastatin. Disabling genetic variants in the candidate genes were not responsible for the bimodal response to cerivastatin. PMID:21386754

Phenomenological and neuropsychological profile across motor variants of delirium in a palliative care unit

LENUS (Irish Health Repository)

Leonard, Maeve

2011-01-01

Studies using composite measurement of cognition suggest that cognitive performance is similar across motor variants of delirium. The authors assessed neuropsychological and symptom profiles in 100 consecutive cases of DSM-IV delirium allocated to motor subtypes in a palliative-care unit: Hypoactive (N=33), Hyperactive (N=18), Mixed (N=26), and No-Alteration motor groups (N=23). The Mixed group had more severe delirium, with highest scores for DRS-R-98 sleep-wake cycle disturbance, hallucinations, delusions, and language abnormalities. Neither the total Cognitive Test for Delirium nor its five neuropsychological domains differed across Hyperactive, Mixed, and Hypoactive motor groups. Most patients (70%) with no motor alteration had DRS-R-98 scores in the mild or subsyndromal range even though they met DSM-IV criteria. Motor variants in delirium have similar cognitive profiles, but mixed cases differ in expression of several noncognitive features.

Functional genetic variants in the vesicular monoamine transporter 1 (VMAT1) modulate emotion processing

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Lohoff, Falk W.; Hodge, Rachel; Narasimhan, Sneha; Nall, Aleksandra; Ferraro, Thomas N.; Mickey, Brian J.; Heitzeg, Mary M.; Langenecker, Scott A.; Zubieta, Jon-Kar; Bogdan, Ryan; Nikolova, Yuliya S.; Drabant, Emily; Hariri, Ahmad R.; Bevilacqua, Laura; Goldman, David; Doyle, Glenn A.

2012-01-01

SUMMARY Emotional behavior is in part heritable and often disrupted in psychopathology. Identification of specific genetic variants that drive this heritability may provide important new insight into molecular and neurobiological mechanisms involved in emotionality. Our results demonstrate that the presynaptic vesicular monoamine transporter 1 (VMAT1) Thr136Ile (rs1390938) polymorphism is functional in vitro, with the Ile allele leading to increased monoamine transport into presynaptic vesicles. Moreover, we show that the Thr136Ile variant predicts differential responses in emotional brain circuits consistent with its effects in vitro. Lastly, deep sequencing of bipolar disorder (BPD) patients and controls identified several rare novel VMAT1 variants. The variant Phe84Ser was only present in individuals with BPD and leads to marked increase monoamine transport in vitro. Taken together, our data show that VMAT1 polymorphisms influence monoamine signaling, the functional response of emotional brain circuits, and risk for psychopathology. PMID:23337945

SORL1 rare variants: a major risk factor for familial early-onset Alzheimer's disease.

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Nicolas, G; Charbonnier, C; Wallon, D; Quenez, O; Bellenguez, C; Grenier-Boley, B; Rousseau, S; Richard, A-C; Rovelet-Lecrux, A; Le Guennec, K; Bacq, D; Garnier, J-G; Olaso, R; Boland, A; Meyer, V; Deleuze, J-F; Amouyel, P; Munter, H M; Bourque, G; Lathrop, M; Frebourg, T; Redon, R; Letenneur, L; Dartigues, J-F; Génin, E; Lambert, J-C; Hannequin, D; Campion, D

2016-06-01

The SORL1 protein plays a protective role against the secretion of the amyloid β peptide, a key event in the pathogeny of Alzheimer's disease. We assessed the impact of SORL1 rare variants in early-onset Alzheimer's disease (EOAD) in a case-control setting. We conducted a whole exome analysis among 484 French EOAD patients and 498 ethnically matched controls. After collapsing rare variants (minor allele frequency ≤1%), we detected an enrichment of disruptive and predicted damaging missense SORL1 variants in cases (odds radio (OR)=5.03, 95% confidence interval (CI)=(2.02-14.99), P=7.49.10(-5)). This enrichment was even stronger when restricting the analysis to the 205 cases with a positive family history (OR=8.86, 95% CI=(3.35-27.31), P=3.82.10(-7)). We conclude that predicted damaging rare SORL1 variants are a strong risk factor for EOAD and that the association signal is mainly driven by cases with positive family history.

Natural Selection and Origin of a Melanistic Allele in North American Gray Wolves.

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Schweizer, Rena M; Durvasula, Arun; Smith, Joel; Vohr, Samuel H; Stahler, Daniel R; Galaverni, Marco; Thalmann, Olaf; Smith, Douglas W; Randi, Ettore; Ostrander, Elaine A; Green, Richard E; Lohmueller, Kirk E; Novembre, John; Wayne, Robert K

2018-05-01

Pigmentation is often used to understand how natural selection affects genetic variation in wild populations since it can have a simple genetic basis, and can affect a variety of fitness-related traits (e.g., camouflage, thermoregulation, and sexual display). In gray wolves, the K locus, a β-defensin gene, causes black coat color via a dominantly inherited KB allele. The allele is derived from dog-wolf hybridization and is at high frequency in North American wolf populations. We designed a DNA capture array to probe the geographic origin, age, and number of introgression events of the KB allele in a panel of 331 wolves and 20 dogs. We found low diversity in KB, but not ancestral ky, wolf haplotypes consistent with a selective sweep of the black haplotype across North America. Further, North American wolf KB haplotypes are monophyletic, suggesting that a single adaptive introgression from dogs to wolves most likely occurred in the Northwest Territories or Yukon. We use a new analytical approach to date the origin of the KB allele in Yukon wolves to between 1,598 and 7,248 years ago, suggesting that introgression with early Native American dogs was the source. Using population genetic simulations, we show that the K locus is undergoing natural selection in four wolf populations. We find evidence for balancing selection, specifically in Yellowstone wolves, which could be a result of selection for enhanced immunity in response to distemper. With these data, we demonstrate how the spread of an adaptive variant may have occurred across a species' geographic range.

Mitochondrial variants in schizophrenia, bipolar disorder, and major depressive disorder.

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Brandi Rollins

Full Text Available Mitochondria provide most of the energy for brain cells by the process of oxidative phosphorylation. Mitochondrial abnormalities and deficiencies in oxidative phosphorylation have been reported in individuals with schizophrenia (SZ, bipolar disorder (BD, and major depressive disorder (MDD in transcriptomic, proteomic, and metabolomic studies. Several mutations in mitochondrial DNA (mtDNA sequence have been reported in SZ and BD patients.Dorsolateral prefrontal cortex (DLPFC from a cohort of 77 SZ, BD, and MDD subjects and age-matched controls (C was studied for mtDNA sequence variations and heteroplasmy levels using Affymetrix mtDNA resequencing arrays. Heteroplasmy levels by microarray were compared to levels obtained with SNaPshot and allele specific real-time PCR. This study examined the association between brain pH and mtDNA alleles. The microarray resequencing of mtDNA was 100% concordant with conventional sequencing results for 103 mtDNA variants. The rate of synonymous base pair substitutions in the coding regions of the mtDNA genome was 22% higher (p = 0.0017 in DLPFC of individuals with SZ compared to controls. The association of brain pH and super haplogroup (U, K, UK was significant (p = 0.004 and independent of postmortem interval time.Focusing on haplogroup and individual susceptibility factors in psychiatric disorders by considering mtDNA variants may lead to innovative treatments to improve mitochondrial health and brain function.

Significance of common variants on human chromosome 8q24 in relation to the risk of prostate cancer in native Japanese men

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Hosoi Takayuki

2009-07-01

Full Text Available Abstract Background Common variants on human chromosome 8q24, rs1447295 (C/A and rs6983267 (T/G, have been recently linked to the prevalence of prostate cancer in European and American populations. Here, we evaluated whether the single-nucleotide polymorphisms rs1447295 and rs6983267 were associated with the risk of sporadic prostate cancer as well as latent prostate cancer in a native Japanese population. Results We analyzed genomic DNA samples from 391 sporadic prostate cancer patients, 323 controls who had died from causes unrelated to cancer and 112 Japanese men who were diagnosed as having latent prostate cancer based on autopsy results. The polymorphisms were determined by allelic discrimination using a fluorescent-based TaqMan assay. The A allele of rs1447295 was significantly associated with the risk of sporadic prostate cancer (p = 0.04; age-adjusted OR, 1.34, while the G allele of rs6983267 showed a trend towards being a high-risk allele (p = 0.06; age-adjusted OR, 1.27. No significant difference between these two polymorphisms and the risk of latent prostate cancer was observed in the present Japanese population. Conclusion Known variants on human chromosome 8q24 may be risk factors for sporadic prostate cancer in native Japanese men.

Association studies of low-frequency coding variants in nonsyndromic cleft lip with or without cleft palate.

Science.gov (United States)

Leslie, Elizabeth J; Carlson, Jenna C; Shaffer, John R; Buxó, Carmen J; Castilla, Eduardo E; Christensen, Kaare; Deleyiannis, Frederic W B; Field, Leigh L; Hecht, Jacqueline T; Moreno, Lina; Orioli, Ieda M; Padilla, Carmencita; Vieira, Alexandre R; Wehby, George L; Feingold, Eleanor; Weinberg, Seth M; Murray, Jeffrey C; Marazita, Mary L

2017-06-01

Nonsyndromic cleft lip with or without cleft palate (NSCL/P) is a group of common human birth defects with complex etiology. Although genome-wide association studies have successfully identified a number of risk loci, these loci only account for about 20% of the heritability of orofacial clefts. The "missing" heritability may be found in rare variants, copy number variants, or interactions. In this study, we investigated the role of low-frequency variants genotyped in 1995 cases and 1626 controls on the Illumina HumanCore + Exome chip. We performed two statistical tests, Sequence Kernel Association Test (SKAT) and Combined Multivariate and Collapsing (CMC) method using two minor allele frequency cutoffs (1% and 5%). We found that a burden of low-frequency coding variants in N4BP2, CDSN, PRTG, and AHRR were associated with increased risk of NSCL/P. Low-frequency variants in other genes were associated with decreased risk of NSCL/P. These results demonstrate that low-frequency variants contribute to the genetic etiology of NSCL/P. © 2017 Wiley Periodicals, Inc.

IL10 low-frequency variants in Behçet's disease patients.

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Matos, Mafalda; Xavier, Joana M; Abrantes, Patrícia; Sousa, Inês; Rei, Nádia; Davatchi, Fereydoun; Shahram, Farhad; Jesus, Gorete; Barcelos, Filipe; Vedes, Joana; Salgado, Manuel; Abdollahi, Bahar Sadeghi; Nadji, Abdolhadi; Moraes-Fontes, Maria Francisca; Shafiee, Niloofar Mojarad; Ghaderibarmi, Fahmida; Vaz Patto, José; Crespo, Jorge; Oliveira, Sofia A

2017-05-01

To explain the missing heritability after the genome-wide association studies era, sequencing studies allow the identification of low-frequency variants with a stronger effect on disease risk. Common variants in the interleukin 10 gene (IL10) have been consistently associated with Behçet's disease (BD) and the goal of this study is to investigate the role of low-frequency IL10 variants in BD susceptibility. To identify IL10 low-frequency variants, a discovery group of 50 Portuguese BD patients were Sanger-sequenced in a 7.7 kb genomic region encompassing the complete IL10 gene, 0.9 kb upstream and 2 kb downstream, and two conserved regions in the putative promoter. To assess if the novel variants are BD- and/or Portuguese-specific, they were assayed in an additional group of BD patients (26 Portuguese and 964 Iranian) and controls (104 Portuguese and 823 Iranian). Rare IL10 coding variants were not detected in BD patients, but we identified 28 known single nucleotide polymorphisms with minor allele frequencies ranging from 0.010 to 0.390, and five novel non-coding variants in five heterozygous cases. ss836185595, located in the IL10 3' untranslated region, was also detected in one Iranian control individual and therefore is not specific to BD. The remaining novel IL10 variants (ss836185596 and ss836185602 in intron 3, ss836185598 and ss836185604 in the putative promoter region) were not found in the replication dataset. This study highlights the importance of screening the whole gene and regulatory regions when searching for novel variants associated with complex diseases, and the need to develop bioinformatics tools to predict the functional impact of non-coding variants and statistical tests which incorporate these predictions. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

Transporter TAP1-637G and Immunoproteasome PSMB9-60H Variants Influence the Risk of Developing Vitiligo in the Saudi Population

Science.gov (United States)

Elhawary, Nasser Attia; Bogari, Neda; Jiffri, Essam Hussien; Rashad, Mona; Fatani, Abdulhamid; Tayeb, Mohammed

2014-01-01

We evaluated whether TAP1-rs1135216 (p.637D>G) and PSMB9-rs17587 (p.60R>H) were significantly associated with the risk and severity of vitiligo among Saudi patients. One hundred seventy-two subjects were genotyped for the TAP1-rs1135216 and PSMB9-rs17587 variants using endonuclease digestions of amplified genomic DNA. The TAP1-rs1135216 and PSMB9-rs17587 mutant alleles were strongly associated with vitiligo, with odds ratios showing five fold and two fold risks (P Vitiligo vulgaris was the most common type of disease, associated with the DG (55%) and GG (46%) genotypes for rs1135216 and with the RH genotype (59%) for rs17587. The heterozygous 637DG and 60RH genotypes were each linked with active phenotypes in 64% of cases. In conclusion, the TAP1-rs1135216 and PSMB9-rs17587 variants are significantly associated with vitiligo, and even one copy of these mutant alleles can influence the risk among Saudis. Vitiligo vulgaris is associated with genotypes containing the mutant G and H alleles. PMID:25548428

Increased burden of cardiovascular disease in carriers of APOL1 genetic variants.

Science.gov (United States)

Ito, Kaoru; Bick, Alexander G; Flannick, Jason; Friedman, David J; Genovese, Giulio; Parfenov, Michael G; Depalma, Steven R; Gupta, Namrata; Gabriel, Stacey B; Taylor, Herman A; Fox, Ervin R; Newton-Cheh, Christopher; Kathiresan, Sekar; Hirschhorn, Joel N; Altshuler, David M; Pollak, Martin R; Wilson, James G; Seidman, J G; Seidman, Christine

2014-02-28

Two distinct alleles in the gene encoding apolipoprotein L1 (APOL1), a major component of high-density lipoprotein, confer protection against Trypanosoma brucei rhodesiense infection and also increase risk for chronic kidney disease. Approximately 14% of Americans with African ancestry carry 2 APOL1 risk alleles, accounting for the high chronic kidney disease burden in this population. We tested whether APOL1 risk alleles significantly increase risk for atherosclerotic cardiovascular disease (CVD) in African Americans. We sequenced APOL1 in 1959 randomly selected African American participants in the Jackson Heart Study (JHS) and evaluated associations between APOL1 genotypes and renal and cardiovascular phenotypes. Previously identified association between APOL1 genotypes and chronic kidney disease was confirmed (P=2.4×10(-6)). Among JHS participants with 2 APOL1 risk alleles, we observed increased risk for CVD (50/763 events among participants without versus 37/280 events among participants with 2 risk alleles; odds ratio, 2.17; P=9.4×10(-4)). We replicated this novel association of APOL1 genotype with CVD in Women's Health Initiative (WHI) participants (66/292 events among participants without versus 37/101 events among participants with 2 risk alleles; odds ratio, 1.98; P=8.37×10(-3); JHS and WHI combined, P=8.5×10(-5); odds ratio, 2.12). The increased risk for CVD conferred by APOL1 alleles was robust to correction for both traditional CVD risk factors and chronic kidney disease. APOL1 variants contribute to atherosclerotic CVD risk, indicating a genetic component to cardiovascular health disparities in individuals of African ancestry. The considerable population of African Americans with 2 APOL1 risk alleles may benefit from intensive interventions to reduce CVD.

Mutation rate heterogeneity and the generation of allele diversity at the human minisatellite MS205 (D16S309).

Science.gov (United States)

May, C A; Jeffreys, A J; Armour, J A

1996-11-01

Many tandemly repeated minisatellite loci display extreme levels of length variation as a consequence of high rates of spontaneous germline mutation altering repeat copy number. Direct screening for new allele lengths by small-pool PCR has shown that instability at the human minisatellite locus MS205 (D16S309) is largely germline specific and usually results in the gain or loss of just a few repeat units. Structural analysis of the order of variant repeats has shown that these events occur preferentially at one end of the tandem array and can result in complex rearrangements including the inter-allelic transfer of repeat units. In contrast, putative mutants recovered from somatic DNA occur at a substantially lower rate and are simple and non-polar in nature. Germline mutation rates vary considerably between alleles, consistent with regulation occurring in cis. Although examination of DNA sequence polymorphisms immediately flanking the minisatellite reveals no definitive associations with germline mutation rate variation, differences in rate may be paralleled by changes in mutation spectrum. These findings help to explain the diversity of MS205 allele structures in modern humans and suggest a common mutation pathway with some other minisatellites.

Structural Analysis of Insulin Minisatellite Alleles Reveals Unusually Large Differences in Diversity between Africans and Non-Africans

Science.gov (United States)

Stead, John D. H.; Jeffreys, Alec J.

2002-01-01

The insulin minisatellite (INS VNTR) associates with susceptibility to a variety of diseases. We have developed a high-resolution system for analyzing variant repeat distributions applicable to all known minisatellite alleles, irrespective of size, which allows lineages of related alleles to be identified. This system has previously revealed extremely low structural diversity in the minisatellite among northern Europeans from the United Kingdom, with all alleles belonging to one of only three highly diverged lineages called “I,” “IIIA,” and “IIIB.” To explore the origins of this remarkably limited lineage diversity, we have characterized an additional 780 alleles from three non-African and three African populations. In total, 22 highly diverged lineages were identified, with structural intermediates absent from extant populations, suggesting a bottleneck within the ancestry of all humans. The difference between levels of diversity in Africans and non-Africans is unusually large, with all 22 lineages identified in Africa compared with only three lineages seen not only in the United Kingdom but also in the other non-African populations. We also find evidence for overrepresentation of lineage I chromosomes in non-Africans. These data are consistent with a common out-of-Africa origin and an unusually tight bottleneck within the ancestry of all non-African populations, possibly combined with differential and positive selection for lineage I alleles in non-Africans. The important implications of these data for future disease-association studies are discussed. PMID:12404181

Evaluation of common type 2 diabetes risk variants in a South Asian population of Sri Lankan descent.

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Neelam Hassanali

Full Text Available Most studies seeking common variant associations with type 2 diabetes (T2D have focused on individuals of European ancestry. These discoveries need to be evaluated in other major ancestral groups, to understand ethnic differences in predisposition, and establish whether these contribute to variation in T2D prevalence and presentation. This study aims to establish whether common variants conferring T2D-risk in Europeans contribute to T2D-susceptibility in the South Asian population of Sri Lanka.Lead single nucleotide polymorphism (SNPs at 37 T2D-risk loci attaining genome-wide significance in Europeans were genotyped in 878 T2D cases and 1523 normoglycaemic controls from Sri Lanka. Association testing was performed by logistic regression adjusting for age and sex and by the Cochran-Mantel-Haenszel test after stratifying according to self-identified ethnolinguistic subgroup. A weighted genetic risk score was generated to examine the combined effect of these SNPs on T2D-risk in the Sri Lankan population.Of the 36 SNPs passing quality control, sixteen showed nominal (p<0.05 association in Sri Lankan samples, fifteen of those directionally-consistent with the original signal. Overall, these association findings were robust to analyses that accounted for membership of ethnolinguistic subgroups. Overall, the odds ratios for 31 of the 36 SNPs were directionally-consistent with those observed in Europeans (p = 3.2×10(-6. Allelic odds ratios and risk allele frequencies in Sri Lankan subjects were not systematically different to those reported in Europeans. Genetic risk score and risk of T2D were strongly related in Sri Lankans (per allele OR 1.10 [95%CI 1.08-1.13], p = 1.2×10(-17.Our data indicate that most T2D-risk variants identified in Europeans have similar effects in South Asians from Sri Lanka, and that systematic difference in common variant associations are unlikely to explain inter-ethnic differences in prevalence or presentation of T2D.

A Multilevel Functional Study of a SNAP25 At-Risk Variant for Bipolar Disorder and Schizophrenia.

Science.gov (United States)

Houenou, Josselin; Boisgontier, Jennifer; Henrion, Annabelle; d'Albis, Marc-Antoine; Dumaine, Anne; Linke, Julia; Wessa, Michèle; Daban, Claire; Hamdani, Nora; Delavest, Marine; Llorca, Pierre-Michel; Lançon, Christophe; Schürhoff, Franck; Szöke, Andrei; Le Corvoisier, Philippe; Barau, Caroline; Poupon, Cyril; Etain, Bruno; Leboyer, Marion; Jamain, Stéphane

2017-10-25

The synaptosomal-associated protein SNAP25 is a key player in synaptic vesicle docking and fusion and has been associated with multiple psychiatric conditions, including schizophrenia, bipolar disorder, and attention-deficit/hyperactivity disorder. We recently identified a promoter variant in SNAP25 , rs6039769 , that is associated with early-onset bipolar disorder and a higher gene expression level in human prefrontal cortex. In the current study, we showed that this variant was associated both in males and females with schizophrenia in two independent cohorts. We then combined in vitro and in vivo approaches in humans to understand the functional impact of the at-risk allele. Thus, we showed in vitro that the rs6039769 C allele was sufficient to increase the SNAP25 transcription level. In a postmortem expression analysis of 33 individuals affected with schizophrenia and 30 unaffected control subjects, we showed that the SNAP25b / SNAP25a ratio was increased in schizophrenic patients carrying the rs6039769 at-risk allele. Last, using genetics imaging in a cohort of 71 subjects, we showed that male risk carriers had an increased amygdala-ventromedial prefrontal cortex functional connectivity and a larger amygdala than non-risk carriers. The latter association has been replicated in an independent cohort of 121 independent subjects. Altogether, results from these multilevel functional studies are bringing strong evidence for the functional consequences of this allelic variation of SNAP25 on modulating the development and plasticity of the prefrontal-limbic network, which therefore may increase the vulnerability to both early-onset bipolar disorder and schizophrenia. SIGNIFICANCE STATEMENT Functional characterization of disease-associated variants is a key challenge in understanding neuropsychiatric disorders and will open an avenue in the development of personalized treatments. Recent studies have accumulated evidence that the SNARE complex, and more specifically

Insulin Like Growth Factor 2 Expression in the Rat Brain Both in Basal Condition and following Learning Predominantly Derives from the Maternal Allele.

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Xiaojing Ye

Full Text Available Insulin like growth factor 2 (Igf2 is known as a maternally imprinted gene involved in growth and development. Recently, Igf2 was found to also be regulated and required in the adult rat hippocampus for long-term memory formation, raising the question of its allelic regulation in adult brain regions following experience and in cognitive processes. We show that, in adult rats, Igf2 is abundantly expressed in brain regions involved in cognitive functions, like hippocampus and prefrontal cortex, compared to the peripheral tissues. In contrast to its maternal imprinting in peripheral tissues, Igf2 is mainly expressed from the maternal allele in these brain regions. The training-dependent increase in Igf2 expression derives proportionally from both parental alleles, and, hence, is mostly maternal. Thus, Igf2 parental expression in the adult rat brain does not follow the imprinting rules found in peripheral tissues, suggesting differential expression regulation and functions of imprinted genes in the brain.

Sexually dimorphic effects of oxytocin receptor gene (OXTR variants on Harm Avoidance

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Stankova Trayana

2012-07-01

Full Text Available Abstract Background Recent research has suggested that oxytocin receptor gene (OXTR variants may account for individual differences in social behavior, the effects of stress and parenting styles. Little is known, however, on a putative role of the gene in heritable temperamental traits. Methods We addressed effects of two common OXTR variants, rs237900 and rs237902, on personality dimensions in 99 healthy subjects using the Temperament and Character Inventory. Results When sex was controlled for and an OXTR genotype*sex interaction term was included in the regression model, 11% of the variance in Harm Avoidance could be explained (uncorrected p ≤ 0.01. Female carriers of the minor alleles scored highest, and a novel A217T mutation emerged in the most harm avoidant male participant. Conclusions Findings lend support to a modulatory effect of common OXTR variants on Harm Avoidance in healthy caucasian women and invite resequencing of the gene in anxiety phenotypes to identify more explanatory functional variation.

No evidence for association of dopamine D2 receptor variant (Ser311/Cys311) with major psychosis

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Tsukasa; Macciardi, F.M.; Badri, F. [Clarke Institute of Psychiatry, Ontario (Canada)] [and others

1996-07-26

We investigated a variant of the dopamine D2 receptor gene (Ser311/Cys311 substitution) in Caucasian patients with schizophrenia (n = 273), delusional disorder (n = 62), bipolar I affective disorder (n = 63), and controls (n = 255). No evidence for association between the receptor variant and any of the diseases was found, even when patients with younger age-of-onset (<25 years) were compared with controls. Futhermore, in a subgroup of schizophrenia patients whom we assessed for negative symptoms, those with the Cys allele did not differ from the remainder of the group. Also, the bipolar affective disorder patients with psychotic features did not show evidence for association with the receptor variant. Thus, our results do not provide evidence for an association between this D2 receptor variant and schizophrenia, or delusional disorder, or bipolar affective disorder. 11 refs., 1 tab.

The influence of VKORC1 and CYP2C9 gene sequence variants on the stability of maintenance phase warfarin treatment

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Skov, Jane; Bladbjerg, Else-Marie; Leppin, Anja

2013-01-01

alleles require lower doses and have increased risk of overanticoagulation. METHODS: We investigated the influence of the above sequence variants on stability of maintenance phase warfarin therapy in a prospective study of 300 consecutive patients followed for one year at an anticoagulant clinic. RESULTS...... of common gene sequence variants in CYP2C9 and VKORC1 on stability of maintenance phase warfarin therapy. Patients attending an anticoagulant clinic using computer-assisted dosage were safely monitored regardless of these sequence variants, but for the small subgroup of patients with the CYP2C9 genotype *2...

Study of Cytochrome P450 2E1 and its allele Variants in Liver Injury of Nondiabetic, Nonalcoholic Steatohepatitis Obese Women

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NELSON M VARELA

2008-01-01

Full Text Available CYP2E1 enzyme is related to nonalcoholic steatohepatitis (NASH due to its ability for reactive oxygen species production, which can be influenced by polymorphisms in the gene. The aim of this study was to investigate hepatic levels, activity, and polymorphisms of the CYP2E1 gene to correlate it with clinical and histological features in 48 female obese NASH patients. Subjects were divided into three groups: (i normal; (ii steatosis; and (iii steatohepatitis. CYP2E1 protein level was assayed in microsomes from liver biopsies, and in vivo chlorzoxazone hydroxylation was determined by HPLC. Genomic DNA was isolated for genotype analysis through PCR. The results showed that liver CYP2E1 content was significantly higher in the steatohepatitis (45%; p=0.024 and steatosis (22%; p=0.032 group compared with normal group. Chlorzoxazone hydroxylase activity showed significant enhancement in the steatohepatitis group (15%, p=0.027 compared with the normal group. c2 rare allele of RsallPstl polymorphisms but no C allele of Dral polymorphism was positively associated with CHZ hydroxylation, which in turn is correlated with liver CYP2E1 content (r=0.59; p=0.026. In conclusion, c2 allele is positively associated with liver injury in NASH. This allele may determine a higher transcriptional activity of the gene, with consequent enhancement in pro-oxidant activity of CYP2E1 thus affording liver toxicity

Two variants on chromosome 17 confer prostate cancer risk, and the one in TCF2 protects against type 2 diabetes

DEFF Research Database (Denmark)

Gudmundsson, Julius; Sulem, Patrick; Steinthorsdottir, Valgerdur

2007-01-01

attributable risk is substantial. One of the variants is in TCF2 (HNF1beta), a gene known to be mutated in individuals with maturity-onset diabetes of the young type 5. Results from eight case-control groups, including one West African and one Chinese, demonstrate that this variant confers protection against...... 17 with the disease. These two variants, 33 Mb apart, fall within a region previously implicated by family-based linkage studies on prostate cancer. The risks conferred by these variants are moderate individually (allele odds ratio of about 1.20), but because they are common, their joint population......We performed a genome-wide association scan to search for sequence variants conferring risk of prostate cancer using 1,501 Icelandic men with prostate cancer and 11,290 controls. Follow-up studies involving three additional case-control groups replicated an association of two variants on chromosome...

Pharmacogenetic analysis of the effects of polymorphisms in APOE, IDE and IL1B on a ketone body based therapeutic on cognition in mild to moderate Alzheimer's disease; a randomized, double-blind, placebo-controlled study

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Poirier Judes

2011-10-01

Full Text Available Abstract Background To examine the effect of genetic variation in APOE, IDE and IL1B on the response to induced ketosis in the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog in subjects with mild to moderate Alzheimer's disease (AD. Methods Genotype effects on ADAS-Cog scores from a randomized, double-blind, placebo-controlled study in mild to moderate AD were examined by an overall two way analysis of variance. In addition, interactions with the carriage status of the epsilon 4 allele of the APOE gene (APOE4 were examined. Results Significant differences in response to induced ketosis were found among non-carriers of putative gain-of-function polymorphisms in rs1143627 and rs16944 in the IL1B gene and among variants of the polymorphism rs2251101 in the IDE gene. Significant differences were found among non-carriers of the APOE4 gene, with notable improvement among the E3/E3 genotype group. Conclusions Variants in APOE, IL1B and IDE may influence the cognitive response to induced ketosis in patients with mild to moderate AD. Trial registration This trial was registered with ClinicalTrials.gov, registry number NCT00142805.

Pharmacogenetic analysis of the effects of polymorphisms in APOE, IDE and IL1B on a ketone body based therapeutic on cognition in mild to moderate Alzheimer's disease; a randomized, double-blind, placebo-controlled study

Science.gov (United States)

2011-01-01

Background To examine the effect of genetic variation in APOE, IDE and IL1B on the response to induced ketosis in the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) in subjects with mild to moderate Alzheimer's disease (AD). Methods Genotype effects on ADAS-Cog scores from a randomized, double-blind, placebo-controlled study in mild to moderate AD were examined by an overall two way analysis of variance. In addition, interactions with the carriage status of the epsilon 4 allele of the APOE gene (APOE4) were examined. Results Significant differences in response to induced ketosis were found among non-carriers of putative gain-of-function polymorphisms in rs1143627 and rs16944 in the IL1B gene and among variants of the polymorphism rs2251101 in the IDE gene. Significant differences were found among non-carriers of the APOE4 gene, with notable improvement among the E3/E3 genotype group. Conclusions Variants in APOE, IL1B and IDE may influence the cognitive response to induced ketosis in patients with mild to moderate AD. Trial registration This trial was registered with ClinicalTrials.gov, registry number NCT00142805. PMID:21992747

Protective Effect of HLA-B*5701 and HLA-C -35 Genetic Variants in HIV-Positive Caucasians from Northern Poland.

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Magdalena Leszczyszyn-Pynka

Full Text Available Association of two HLA class I variants with HIV-1 pretreatment viremia, CD4+ T cell count at the care-entry and CD4+ T cell nadir.414 HIV-positive Caucasians (30% women aged 19-73 years were genotyped for HLA-C -35 (rs9264942 and HLA-B*5701 variants. HIV-1 viral load, as well as CD4+ T cell count at care-entry and nadir, were compared across alleles, genotypes and haplotypes.HLA-C -35 C/C genotype was found in 17.6% patients, C/T genotype in 48.1%, and T/T genotype in 34.3% patients. HLA-B*5701 variant was present in 5.8% of studied population. HIV plasma viremia in the group with C allele was significantly lower (p=0.0002 compared to T/T group [mean:4.66 log (SD:1.03 vs. 5.07 (SD:0.85 log HIV-RNA copies/ml, respectively], while CD4+ T cell count at baseline was notably higher among C allele carriers compared to T/T homozygotes [median: 318 (IQR:127-537 cells/μl vs. median: 203 (IQR:55-410 cells/μl, respectively] (p=0.0007. Moreover, CD4+ T cell nadir among patients with C allele [median: 205 (IQR:83.5-390 cells/μl] was significantly higher compared to T/T group [median: 133 (IQR:46-328 cells/μl] (p=0.006. Among cases with HLA-B*5701 allele, significantly lower pretreatment viremia and higher baseline CD4+ T cell count were found (mean: 4.08 [SD: 1.2] vs. mean: 4.84 [SD:0.97] log HIV-RNA copies/ml, p=0.003 and 431 vs. 270 cells/μl, p=0.04, respectively compared to HLA-B*5701 negative individuals. The lowest viremia (mean: 3.85 log [SD:1.3] HIV-RNA copies/ml and the highest baseline and nadir CD4+ T cell [median: 476 (IQR:304-682 vs. median: 361 (IQR: 205-574 cells/μl, respectively were found in individuals with HLA-B*5701(+/HLA-C -35 C/C haplotype.HLA-C -35 C and HLA-B*5701 allele exert a favorable effect on the immunological (higher baseline and nadir CD4+ T cell count and virologic (lower pretreatment HIV viral load variables. This protective effect is additive for the compound HLA-B*5701(+/HLA-C -35 C/C haplotype.

The longitudinal association of common susceptibility variants for type 2 diabetes and obesity with fasting glucose level and BMI

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Beilby John P

2010-10-01

Full Text Available Abstract Background Variation in the effects of genetic variants on physiological traits over time or with age may alter the trajectories of these traits. However, few studies have investigated this possibility for variants associated with type 2 diabetes or obesity, and these show little consensus. We aimed to characterise the possible longitudinal associations of common diabetes-susceptibility variants in the KCNJ11, PPARG, TCF7L2, IGF2BP2, CDKAL1, SLC30A8 and HHEX gene loci, with fasting glucose level; and of an obesity-associated variant in the FTO gene, with body mass index (BMI. Methods The study analysed data from the Busselton Health Study (n = 4,554. Cross-sectional association analyses included family data and used the total association test. Longitudinal association analyses of unrelated participant data (n = 2,864 used linear mixed-effects models. Results In cross-sectional analyses, we observed associations of the T allele at the IGF2BP2 single nucleotide polymorphism (SNP rs4402960 with raised fasting glucose (p = 0.045, and the A allele at the FTO SNP rs9939609 with raised BMI (p = 0.003. Longitudinal analyses showed no significant associations between SNPs and changes in fasting glucose or BMI in the same individuals, either over mean follow-up times of 18.7 and 21.8 years respectively, or with age during adulthood. Conclusions There was no indication that the effects of common type 2 diabetes variants on fasting glucose varied with age during adulthood or over time.

Impact of ABCB1 Variants on Neutrophil Depression: A Pharmacogenomic Study of Paclitaxel in 92 Women with Ovarian Cancer

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Bergmann, Troels K; Andersen, Charlotte Brasch; Gréen, Henrik

2012-01-01

prospectively recruited Scandinavian Caucasian women with primary ovarian cancer who were treated with paclitaxel and carboplatin. A single investigator assessed the clinical toxicity in 97% of the patients. Patients carrying variant alleles of ABCB1 C3435T experienced more pronounced neutrophil decrease (63...

HLA-DRB1 alleles in four Amerindian populations from Argentina and Paraguay

Science.gov (United States)

2009-01-01

The major histocompatibility complex (MHC) is one of the biological systems of major polymorphisms. The study of HLA class II variability has allowed the identification of several alleles that are characteristic to Amerindian populations, and it is an excellent tool to define the relations and biological affinities among them. In this work, we analyzed the allelic distribution of the HLA-DRB1 class II locus in four Amerindian populations: Mapuche (n = 34) and Tehuelche (n = 23) from the Patagonian region of Argentina, and Wichi SV (n = 24) and Lengua (n = 17) from the Argentinean and Paraguayan Chaco regions, respectively. In all of these groups, relatively high frequencies of Amerindian HLA-DRB1 alleles were observed (DRB1*0403, DRB1*0407, DRB1*0411, DRB1*0417, DRB1*0802, DRB1*0901, DRB1*1402, DRB1*1406 and DRB1*1602). However, we also detected the presence of non-Amerindian variants in Mapuche (35%) and Tehuelche (22%). We compared our data with those obtained in six indigenous groups of the Argentinean Chaco region and in a sample from Buenos Aires City. The genetic distance dendrogram showed a clear-cut division between the Patagonian and Chaco populations, which formed two different clusters. In spite of their linguistic differences, it can be inferred that the biological affinities observed are in concordance with the geographic distributions and interethnic relations established among the groups studied. PMID:21637670

Association between Age at Diagnosis of Graves' Disease and Variants in Genes Involved in Immune Response

Science.gov (United States)

Jurecka-Lubieniecka, Beata; Ploski, Rafal; Kula, Dorota; Krol, Aleksandra; Bednarczuk, Tomasz; Kolosza, Zofia; Tukiendorf, Andrzej; Szpak-Ulczok, Sylwia; Stanjek-Cichoracka, Anita; Polanska, Joanna; Jarzab, Barbara

2013-01-01

Background Graves' disease (GD) is a complex disease in which genetic predisposition is modified by environmental factors. The aim of the study was to examine the association between genetic variants in genes encoding proteins involved in immune response and the age at diagnosis of GD. Methods 735 GD patients and 1216 healthy controls from Poland were included into the study. Eight genetic variants in the HLA-DRB1, TNF, CTLA4, CD40, NFKb, PTPN22, IL4 and IL10 genes were genotyped. Patients were stratified by the age at diagnosis of GD and the association with genotype was analysed. Results Polymorphism in the HLA-DRB1, TNF and CTLA4 genes were associated with GD. The carriers of the HLA DRB1*03 allele were more frequent in patients with age at GD diagnosis ≤30 years than in patients with older age at GD diagnosis. Conclusions HLADRB1*03 allele is associated with young age at diagnosis of Graves' disease in polish population. PMID:23544060

Development of a High Resolution Virulence Allelic Profiling (HReVAP) Approach Based on the Accessory Genome of Escherichia coli to Characterize Shiga-Toxin Producing E. coli (STEC)

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Michelacci, Valeria; Orsini, Massimiliano; Knijn, Arnold; Delannoy, Sabine; Fach, Patrick; Caprioli, Alfredo; Morabito, Stefano

2016-01-01

Shiga-toxin producing Escherichia coli (STEC) strains possess a large accessory genome composed of virulence genes existing in multiple allelic variants, which sometimes segregate with specific STEC subpopulations. We analyzed the allelic variability of 91 virulence genes of STEC by Real Time PCR followed by melting curves analysis in 713 E. coli strains including 358 STEC. The 91 genes investigated were located on the locus of enterocyte effacement (LEE), OI-57, and OI-122 pathogenicity islands and displayed a total of 476 alleles in the study population. The combinations of the 91 alleles of each strain were termed allelic signatures and used to perform cluster analyses. We termed such an approach High Resolution Virulence Allelic Profiling (HReVAP) and used it to investigate the phylogeny of STEC of multiple serogroups. The dendrograms obtained identified groups of STEC segregating approximately with the serogroups and allowed the identification of subpopulations within the single groups. The study of the allelic signatures provided further evidence of the coevolution of the LEE and OI-122, reflecting the occurrence of their acquisition through a single event. The HReVAP analysis represents a sensitive tool for studying the evolution of LEE-positive STEC. PMID:26941726

Tracking human migrations by the analysis of the distribution of HLA alleles, lineages and haplotypes in closed and open populations

Science.gov (United States)

Vina, Marcelo A. Fernandez; Hollenbach, Jill A.; Lyke, Kirsten E.; Sztein, Marcelo B.; Maiers, Martin; Klitz, William; Cano, Pedro; Mack, Steven; Single, Richard; Brautbar, Chaim; Israel, Shosahna; Raimondi, Eduardo; Khoriaty, Evelyne; Inati, Adlette; Andreani, Marco; Testi, Manuela; Moraes, Maria Elisa; Thomson, Glenys; Stastny, Peter; Cao, Kai

2012-01-01

The human leucocyte antigen (HLA) system shows extensive variation in the number and function of loci and the number of alleles present at any one locus. Allele distribution has been analysed in many populations through the course of several decades, and the implementation of molecular typing has significantly increased the level of diversity revealing that many serotypes have multiple functional variants. While the degree of diversity in many populations is equivalent and may result from functional polymorphism(s) in peptide presentation, homogeneous and heterogeneous populations present contrasting numbers of alleles and lineages at the loci with high-density expression products. In spite of these differences, the homozygosity levels are comparable in almost all of them. The balanced distribution of HLA alleles is consistent with overdominant selection. The genetic distances between outbred populations correlate with their geographical locations; the formal genetic distance measurements are larger than expected between inbred populations in the same region. The latter present many unique alleles grouped in a few lineages consistent with limited founder polymorphism in which any novel allele may have been positively selected to enlarge the communal peptide-binding repertoire of a given population. On the other hand, it has been observed that some alleles are found in multiple populations with distinctive haplotypic associations suggesting that convergent evolution events may have taken place as well. It appears that the HLA system has been under strong selection, probably owing to its fundamental role in varying immune responses. Therefore, allelic diversity in HLA should be analysed in conjunction with other genetic markers to accurately track the migrations of modern humans. PMID:22312049

Single nucleotide polymorphisms at erythropoietin, superoxide dismutase 1, splicing factor, arginine/serin-rich 15 and plasmacytoma variant translocation genes association with diabetic nephropathy

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Maisaa Alwohhaib

2014-01-01

Full Text Available A number of genes have been identified in diabetic nephropathy. Association between diabetes-associated nephropathy and polymorphisms in the erythropoietin (EPO gene, variants in the superoxide dismutase 1 (SOD1 gene and plasmacytoma variant translocation 1 (PVT1 gene have been identified. The EPO, SOD1:SFRS15 and PVT1 genes were genotyped using the single nucleotide polymorphism (SNP technique in 38 diabetic nephropathy patients (Group 1 compared with 64 diabetic type 2 subjects without nephropathy (Group 2 at the Mubarak Alkabeer Hospital, Kuwait. The frequency of the risk allele T of the EPO (rs1617640 gene was high in both groups (0.96 in Group 1 and 0.92 in Group 2. Similarly, SNPs of the PVT1 (rs2720709 gene showed a higher frequency of the risk allele G in both groups (0.70 in the Group 1 and 0.68 in Group 2. Although the frequency of the risk allele A was higher than the frequency of the non-risk allele C of the SOD1:SFRS15 gene in both groups, the lowest probability value was observed in those gene SNPs (P = 0.05. We observed that the A allele of the SOD1:SFRS15 gene (rs17880135 was more frequently present in Group 1 (0.75 compared with Group 2 (0.62. Susceptibility to diabetes-associated nephropathy is partially mediated by genetic predisposition, and screening tests may open the gate for new therapeutic approaches.

Whole genome sequencing reveals a novel deletion variant in the KIT gene in horses with white spotted coat colour phenotypes.

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Dürig, N; Jude, R; Holl, H; Brooks, S A; Lafayette, C; Jagannathan, V; Leeb, T

2017-08-01

White spotting phenotypes in horses can range in severity from the common white markings up to completely white horses. EDNRB, KIT, MITF, PAX3 and TRPM1 represent known candidate genes for such phenotypes in horses. For the present study, we re-investigated a large horse family segregating a variable white spotting phenotype, for which conventional Sanger sequencing of the candidate genes' individual exons had failed to reveal the causative variant. We obtained whole genome sequence data from an affected horse and specifically searched for structural variants in the known candidate genes. This analysis revealed a heterozygous ~1.9-kb deletion spanning exons 10-13 of the KIT gene (chr3:77,740,239_77,742,136del1898insTATAT). In continuity with previously named equine KIT variants we propose to designate the newly identified deletion variant W22. We had access to 21 horses carrying the W22 allele. Four of them were compound heterozygous W20/W22 and had a completely white phenotype. Our data suggest that W22 represents a true null allele of the KIT gene, whereas the previously identified W20 leads to a partial loss of function. These findings will enable more precise genetic testing for depigmentation phenotypes in horses. © 2017 Stichting International Foundation for Animal Genetics.

Allelic heterogeneity and trade-off shape natural variation for response to soil micronutrient.

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Seifollah Poormohammad Kiani

Full Text Available As sessile organisms, plants have to cope with diverse environmental constraints that may vary through time and space, eventually leading to changes in the phenotype of populations through fixation of adaptive genetic variation. To fully comprehend the mechanisms of evolution and make sense of the extensive genotypic diversity currently revealed by new sequencing technologies, we are challenged with identifying the molecular basis of such adaptive variation. Here, we have identified a new variant of a molybdenum (Mo transporter, MOT1, which is causal for fitness changes under artificial conditions of both Mo-deficiency and Mo-toxicity and in which allelic variation among West-Asian populations is strictly correlated with the concentration of available Mo in native soils. In addition, this association is accompanied at different scales with patterns of polymorphisms that are not consistent with neutral evolution and show signs of diversifying selection. Resolving such a case of allelic heterogeneity helps explain species-wide phenotypic variation for Mo homeostasis and potentially reveals trade-off effects, a finding still rarely linked to fitness.

Evidence for Association of the E23K Variant of KCNJ11 Gene with Type 2 Diabetes in Tunisian Population: Population-Based Study and Meta-Analysis

OpenAIRE

Lasram, Khaled; Ben Halim, Nizar; Hsouna, Sana; Kefi, Rym; Arfa, Imen; Ghazouani, Welid; Jamoussi, Henda; Benrahma, Houda; Kharrat, Najla; Rebai, Ahmed; Ben Ammar, Slim; Bahri, Sonia; Barakat, Abdelhamid; Abid, Abdelmajid; Abdelhak, Sonia

2014-01-01

Aims. Genetic association studies have reported the E23K variant of KCNJ11 gene to be associated with Type 2 diabetes. In Arab populations, only four studies have investigated the role of this variant. We aimed to replicate and validate the association between the E23K variant and Type 2 diabetes in Tunisian and Arab populations. Methods. We have performed a case-control association study including 250 Tunisian patients with Type 2 diabetes and 267 controls. Allelic association has also been ...

Association Analysis of Genetic Variants with Type 2 Diabetes in a Mongolian Population in China

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Haihua Bai

2015-01-01

Full Text Available The large scale genome wide association studies (GWAS have identified approximately 80 single nucleotide polymorphisms (SNPs conferring susceptibility to type 2 diabetes (T2D. However, most of these loci have not been replicated in diverse populations and much genetic heterogeneity has been observed across ethnic groups. We tested 28 SNPs previously found to be associated with T2D by GWAS in a Mongolian sample of Northern China (497 diagnosed with T2D and 469 controls for association with T2D and diabetes related quantitative traits. We replicated T2D association of 11 SNPs, namely, rs7578326 (IRS1, rs1531343 (HMGA2, rs8042680 (PRC1, rs7578597 (THADA, rs1333051 (CDKN2, rs6723108 (TMEM163, rs163182 and rs2237897 (KCNQ1, rs1387153 (MTNR1B, rs243021 (BCL11A, and rs10229583 (PAX4 in our sample. Further, we showed that risk allele of the strongest T2D associated SNP in our sample, rs757832 (IRS1, is associated with increased level of TG. We observed substantial difference of T2D risk allele frequency between the Mongolian sample and the 1000G Caucasian sample for a few SNPs, including rs6723108 (TMEM163 whose risk allele reaches near fixation in the Mongolian sample. Further study of genetic architecture of these variants in susceptibility of T2D is needed to understand the role of these variants in heterogeneous populations.

Use of allele-specific FAIRE to determine functional regulatory polymorphism using large-scale genotyping arrays

DEFF Research Database (Denmark)

Smith, Frank Andrew; Howard, Philip; Shah, Sonia

2012-01-01

Following the widespread use of genome-wide association studies (GWAS), focus is turning towards identification of causal variants rather than simply genetic markers of diseases and traits. As a step towards a high-throughput method to identify genome-wide, non-coding, functional regulatory...... discrimination. Examination of this SNP in two prospective Caucasian cohorts comprising 15,000 individuals confirmed the association with HDL-C levels (combined beta = 0.016; p = 0.0006), and analysis of gene expression identified an allelic association with LXR-α expression in heart tissue. Using increasingly...

The allele frequency of two single nucleotide polymorphisms in the von Hippel-Lindau (VHL) tumor suppressor gene in the Taiwanese population.

Science.gov (United States)

Wang, Wen-Chung; Chen, Hui-Ju; Shu, Wei-Pang; Tsai, Yi-Chang; Lai, Yen-Chein

2011-10-01

The von Hippel-Lindau (VHL) tumor suppressor gene located on chromosome 3p25-26 is implicated in VHL disease. Two informative single nucleotide polymorphisms are at positions 19 and 1149 on the nucleotide sequence from Gene Bank NM_000551. In this study we examined the allele frequencies at these two loci in the Taiwanese population and compared the results to those from European ethnic populations. The allele frequency was examined in 616 healthy individuals including 301 university students and 315 neonates. Both A/G polymorphisms were investigated using restriction fragment length polymorphism analysis created by restriction enzymes, BsaJ I and Acc I. Among these subjects, the allele frequencies at 19 SNP and 1149 SNP for variant G were 0.130 and 0.133, respectively. And these results were significant differences from those of the Caucasian populations. In addition, 90% of the tested subjects had identical genotypes at these two loci suggesting the existence of nonrandom association of alleles. We found that the G allele frequency at these two loci in the Taiwanese population is much lower than that in people from Western countries. This phenomenon may be attributed to ethnic effects. Copyright © 2011. Published by Elsevier B.V.

Creation of Novel Protein Variants with CRISPR/Cas9-Mediated Mutagenesis: Turning a Screening By-Product into a Discovery Tool.

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Katherine F Donovan

Full Text Available CRISPR/Cas9 screening has proven to be a versatile tool for genomics research. Based on unexpected results from a genome-wide screen, we developed a CRISPR/Cas9-mediated approach to mutagenesis, exploiting the allelic diversity generated by error-prone non-homologous end-joining (NHEJ to identify novel gain-of-function and drug resistant alleles of the MAPK signaling pathway genes MEK1 and BRAF. We define the parameters of a scalable technique to easily generate cell populations containing thousands of endogenous allelic variants to map gene functions. Further, these results highlight an unexpected but important phenomenon, that Cas9-induced gain-of-function alleles are an inherent by-product of normal Cas9 loss-of-function screens and should be investigated during analysis of data from large-scale positive selection screens.

Exome Sequencing Identifies Potential Risk Variants for Mendelian Disorders at High Prevalence in Qatar

Science.gov (United States)

Rodriguez-Flores, Juan L.; Fakhro, Khalid; Hackett, Neil R.; Salit, Jacqueline; Fuller, Jennifer; Agosto-Perez, Francisco; Gharbiah, Maey; Malek, Joel A.; Zirie, Mahmoud; Jayyousi, Amin; Badii, Ramin; Al-Marri, Ajayeb Al-Nabet; Chouchane, Lotfi; Stadler, Dora J.; Hunter-Zinck, Haley; Mezey, Jason G.; Crystal, Ronald G.

2013-01-01

Exome sequencing of families of related individuals has been highly successful in identifying genetic polymorphisms responsible for Mendelian disorders. Here, we demonstrate the value of the reverse approach, where we use exome sequencing of a sample of unrelated individuals to analyze allele frequencies of known causal mutations for Mendelian diseases. We sequenced the exomes of 100 individuals representing the three major genetic subgroups of the Qatari population (Q1 Bedouin, Q2 Persian-South Asian, Q3 African) and identified 37 variants in 33 genes with effects on 36 clinically significant Mendelian diseases. These include variants not present in 1000 Genomes and variants at high frequency when compared to 1000 Genomes populations. Several of these Mendelian variants were only segregating in one Qatari subpopulation, where the observed subpopulation specificity trends were confirmed in an independent population of 386 Qataris. Pre-marital genetic screening in Qatar tests for only 4 out of the 37, such that this study provides a set of Mendelian disease variants with potential impact on the epidemiological profile of the population that could be incorporated into the testing program if further experimental and clinical characterization confirms high penetrance. PMID:24123366

De novo and inherited private variants in MAP1B in periventricular nodular heterotopia.

Science.gov (United States)

Heinzen, Erin L; O'Neill, Adam C; Zhu, Xiaolin; Allen, Andrew S; Bahlo, Melanie; Chelly, Jamel; Dobyns, William B; Freytag, Saskia; Guerrini, Renzo; Leventer, Richard J; Poduri, Annapurna; Robertson, Stephen P; Walsh, Christopher A; Zhang, Mengqi

2018-05-08

Periventricular nodular heterotopia (PVNH) is a malformation of cortical development commonly associated with epilepsy. We exome sequenced 202 individuals with sporadic PVNH to identify novel genetic risk loci. We first performed a trio-based analysis and identified 219 de novo variants. Although no novel genes were implicated in this initial analysis, PVNH cases were found overall to have a significant excess of nonsynonymous de novo variants in intolerant genes (p = 3.27x10-7), suggesting a role for rare new alleles in genes yet to be associated with the condition. Using a gene-level collapsing analysis comparing cases and controls, we identified a genome-wide significant signal driven by four ultra-rare loss-of-function heterozygous variants in MAP1B, including one de novo variant. In at least one instance, the MAP1B variant was inherited from a parent with previously undiagnosed PVNH. The PVNH was frontally predominant and associated with perisylvian polymicrogyria. These results implicate MAP1B in PVNH. More broadly, our findings suggest that detrimental mutations likely arising in immediately preceding generations with incomplete penetrance may also be responsible for some apparently sporadic diseases.

Beta2-adrenergic receptor allele frequencies in the Quechua, a high altitude native population.

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Rupert, J L; Monsalve, M V; Devine, D V; Hochachka, P W

2000-03-01

The beta2-adrenergic receptor is involved in the control of numerous physiological processes and, as the primary catecholamine receptor in the lungs, is of particular importance in the regulation of pulmonary function. There are several polymorphic loci in the beta2-adrenergic receptor gene that have alleles that alter receptor function, including two (A/G46, G/C79) that increase agonist sensitivity. As such a phenotype may increase vaso and bronchial dilation, thereby facilitating air and blood flow through the lungs, we hypothesized that selection may have favoured these alleles in high altitude populations as part of an adaptive strategy to deal with the hypoxic conditions characteristic of such environments. We tested this hypothesis by determining the allele frequencies for these two polymorphisms, as well one additional missense mutation (C/T491) and two silent mutations (G/A252 and C/A523) in 63 Quechua speaking natives from communities located between 3200 and 4200 m on the Peruvian altiplano. These frequencies were compared with those of two lowland populations, one native American (Na-Dene from the west coast of Canada) and one Caucasian of Western European descent. The Quechua manifest many of the pulmonary characteristics of high altitude populations and differences in allele frequencies between the Quechua and lowlanders could be indicative of a selective advantage conferred by certain genotypes in high altitude environments. Allele frequencies varied between populations at some loci and patterns of linkage disequilibrium differed between the old-world and new-world samples; however, as these populations are not closely related, significant variation would be expected due to stochastic effects alone. Neither of the alleles associated with increased receptor sensitivity (A46, G79) was significantly over-represented in the Quechua compared with either lowland group. The Quechua were monomorphic for the C allele at base 79. This variant has been

Who's behind that mask and cape? The Asian leopard cat's Agouti (ASIP) allele likely affects coat colour phenotype in the Bengal cat breed.

Science.gov (United States)

Gershony, L C; Penedo, M C T; Davis, B W; Murphy, W J; Helps, C R; Lyons, L A

2014-12-01

Coat colours and patterns are highly variable in cats and are determined mainly by several genes with Mendelian inheritance. A 2-bp deletion in agouti signalling protein (ASIP) is associated with melanism in domestic cats. Bengal cats are hybrids between domestic cats and Asian leopard cats (Prionailurus bengalensis), and the charcoal coat colouration/pattern in Bengals presents as a possible incomplete melanism. The complete coding region of ASIP was directly sequenced in Asian leopard, domestic and Bengal cats. Twenty-seven variants were identified between domestic and leopard cats and were investigated in Bengals and Savannahs, a hybrid with servals (Leptailurus serval). The leopard cat ASIP haplotype was distinguished from domestic cat by four synonymous and four non-synonymous exonic SNPs, as well as 19 intronic variants, including a 42-bp deletion in intron 4. Fifty-six of 64 reported charcoal cats were compound heterozygotes at ASIP, with leopard cat agouti (A(P) (be) ) and domestic cat non-agouti (a) haplotypes. Twenty-four Bengals had an additional unique haplotype (A2) for exon 2 that was not identified in leopard cats, servals or jungle cats (Felis chaus). The compound heterozygote state suggests the leopard cat allele, in combination with the recessive non-agouti allele, influences Bengal markings, producing a darker, yet not completely melanistic coat. This is the first validation of a leopard cat allele segregating in the Bengal breed and likely affecting their overall pelage phenotype. Genetic testing services need to be aware of the possible segregation of wild felid alleles in all assays performed on hybrid cats. © 2014 The Authors. Animal Genetics published by John Wiley & Sons Ltd on behalf of Stichting International Foundation for Animal Genetics.

A genome-wide scan for common alleles affecting risk for autism

Science.gov (United States)

Anney, Richard; Klei, Lambertus; Pinto, Dalila; Regan, Regina; Conroy, Judith; Magalhaes, Tiago R.; Correia, Catarina; Abrahams, Brett S.; Sykes, Nuala; Pagnamenta, Alistair T.; Almeida, Joana; Bacchelli, Elena; Bailey, Anthony J.; Baird, Gillian; Battaglia, Agatino; Berney, Tom; Bolshakova, Nadia; Bölte, Sven; Bolton, Patrick F.; Bourgeron, Thomas; Brennan, Sean; Brian, Jessica; Carson, Andrew R.; Casallo, Guillermo; Casey, Jillian; Chu, Su H.; Cochrane, Lynne; Corsello, Christina; Crawford, Emily L.; Crossett, Andrew; Dawson, Geraldine; de Jonge, Maretha; Delorme, Richard; Drmic, Irene; Duketis, Eftichia; Duque, Frederico; Estes, Annette; Farrar, Penny; Fernandez, Bridget A.; Folstein, Susan E.; Fombonne, Eric; Freitag, Christine M.; Gilbert, John; Gillberg, Christopher; Glessner, Joseph T.; Goldberg, Jeremy; Green, Jonathan; Guter, Stephen J.; Hakonarson, Hakon; Heron, Elizabeth A.; Hill, Matthew; Holt, Richard; Howe, Jennifer L.; Hughes, Gillian; Hus, Vanessa; Igliozzi, Roberta; Kim, Cecilia; Klauck, Sabine M.; Kolevzon, Alexander; Korvatska, Olena; Kustanovich, Vlad; Lajonchere, Clara M.; Lamb, Janine A.; Laskawiec, Magdalena; Leboyer, Marion; Le Couteur, Ann; Leventhal, Bennett L.; Lionel, Anath C.; Liu, Xiao-Qing; Lord, Catherine; Lotspeich, Linda; Lund, Sabata C.; Maestrini, Elena; Mahoney, William; Mantoulan, Carine; Marshall, Christian R.; McConachie, Helen; McDougle, Christopher J.; McGrath, Jane; McMahon, William M.; Melhem, Nadine M.; Merikangas, Alison; Migita, Ohsuke; Minshew, Nancy J.; Mirza, Ghazala K.; Munson, Jeff; Nelson, Stanley F.; Noakes, Carolyn; Noor, Abdul; Nygren, Gudrun; Oliveira, Guiomar; Papanikolaou, Katerina; Parr, Jeremy R.; Parrini, Barbara; Paton, Tara; Pickles, Andrew; Piven, Joseph; Posey, David J; Poustka, Annemarie; Poustka, Fritz; Prasad, Aparna; Ragoussis, Jiannis; Renshaw, Katy; Rickaby, Jessica; Roberts, Wendy; Roeder, Kathryn; Roge, Bernadette; Rutter, Michael L.; Bierut, Laura J.; Rice, John P.; Salt, Jeff; Sansom, Katherine; Sato, Daisuke; Segurado, Ricardo; Senman, Lili; Shah, Naisha; Sheffield, Val C.; Soorya, Latha; Sousa, Inês; Stoppioni, Vera; Strawbridge, Christina; Tancredi, Raffaella; Tansey, Katherine; Thiruvahindrapduram, Bhooma; Thompson, Ann P.; Thomson, Susanne; Tryfon, Ana; Tsiantis, John; Van Engeland, Herman; Vincent, John B.; Volkmar, Fred; Wallace, Simon; Wang, Kai; Wang, Zhouzhi; Wassink, Thomas H.; Wing, Kirsty; Wittemeyer, Kerstin; Wood, Shawn; Yaspan, Brian L.; Zurawiecki, Danielle; Zwaigenbaum, Lonnie; Betancur, Catalina; Buxbaum, Joseph D.; Cantor, Rita M.; Cook, Edwin H.; Coon, Hilary; Cuccaro, Michael L.; Gallagher, Louise; Geschwind, Daniel H.; Gill, Michael; Haines, Jonathan L.; Miller, Judith; Monaco, Anthony P.; Nurnberger, John I.; Paterson, Andrew D.; Pericak-Vance, Margaret A.; Schellenberg, Gerard D.; Scherer, Stephen W.; Sutcliffe, James S.; Szatmari, Peter; Vicente, Astrid M.; Vieland, Veronica J.; Wijsman, Ellen M.; Devlin, Bernie; Ennis, Sean; Hallmayer, Joachim

2010-01-01

Although autism spectrum disorders (ASDs) have a substantial genetic basis, most of the known genetic risk has been traced to rare variants, principally copy number variants (CNVs). To identify common risk variation, the Autism Genome Project (AGP) Consortium genotyped 1558 rigorously defined ASD families for 1 million single-nucleotide polymorphisms (SNPs) and analyzed these SNP genotypes for association with ASD. In one of four primary association analyses, the association signal for marker rs4141463, located within MACROD2, crossed the genome-wide association significance threshold of P < 5 × 10−8. When a smaller replication sample was analyzed, the risk allele at rs4141463 was again over-transmitted; yet, consistent with the winner's curse, its effect size in the replication sample was much smaller; and, for the combined samples, the association signal barely fell below the P < 5 × 10−8 threshold. Exploratory analyses of phenotypic subtypes yielded no significant associations after correction for multiple testing. They did, however, yield strong signals within several genes, KIAA0564, PLD5, POU6F2, ST8SIA2 and TAF1C. PMID:20663923

Influences of the common FTO rs9939609 variant on inflammatory markers throughout a broad range of body mass index

DEFF Research Database (Denmark)

Zimmermann, Esther; Skogstrand, Kristin; Hougaard, David M

2011-01-01

A recent study reported that the fatness associated A-allele of FTO rs9939609 increased plasma high sensitivity C-reactive protein (hs-CRP) levels independent of fatness. We aimed to investigate if this gene variant had fatness-independent effects on plasma hs-CRP and 10 additional circulating...

Comprehensive analysis of RET common and rare variants in a series of Spanish Hirschsprung patients confirms a synergistic effect of both kinds of events

Directory of Open Access Journals (Sweden)

Castaño Luis

2011-10-01

Full Text Available Abstract Background RET is the major gene associated to Hirschsprung disease (HSCR with differential contributions of its rare and common, coding and noncoding mutations to the multifactorial nature of this pathology. In the present study, we have performed a comprehensive study of our HSCR series evaluating the involvement of both RET rare variants (RVs and common variants (CVs in the context of the disease. Methods RET mutational screening was performed by dHPLC and direct sequencing for the identification of RVs. In addition Taqman technology was applied for the genotyping of 3 RET CVs previously associated to HSCR, including a variant lying in an enhancer domain within RET intron 1 (rs2435357. Statistical analyses were performed using the SPSS v.17.0 to analyze the distribution of the variants. Results Our results confirm the strongest association to HSCR for the "enhancer" variant, and demonstrate a significantly higher impact of it in male versus female patients. Integration of the RET RVs and CVs analysis showed that in 91.66% of cases with both kinds of mutational events, the enhancer allele is in trans with the allele bearing the RET RV. Conclusions A gender effect exists on both the transmission and distribution of rare coding and common HSCR causing mutations. In addition, these RET CVs and RVs seem to act in a synergistic way leading to HSCR phenotype.

The SLC4A7 variant rs4973768 is associated with breast cancer risk: evidence from a case-control study and a meta-analysis.

Science.gov (United States)

Chen, Wei; Zhong, Rong; Ming, Jie; Zou, Li; Zhu, Beibei; Lu, Xuzai; Ke, Juntao; Zhang, Yu; Liu, Li; Miao, Xiaoping; Huang, Tao

2012-12-01

Recent genome-wide association study has identified a genetic variant rs4973768, located in 3'-UTR of solute carrier family 4, sodium bicarbonate cotransporter, member 7 (SLC4A7), was associated with increased risk of breast cancer (BC). However, several following replication studies cannot yield consistent results. We thus conducted a hospital-based case-control study including 485 patients and 514 controls, combined a meta-analysis including 108,632 cases and 135,818 controls to explore the relationship between this variant and BC risk. Our case-control study showed that rs4973768 was significantly associated with increased BC risk with the odds ratio (OR) of 1.29 (95 % confidence interval [CI]: 1.04-1.60) under the allelic model. In addition, the meta-analysis also indicated that the variant slightly increased the risk of BC with the pooled OR of the per-allele effect being 1.08 (95 % CI: 1.04-1.11) although with significant heterogeneity between studies. Stratified analyses showed that ethnicity, sample size, and study design may explain part of the heterogeneity. Moreover, the bioinformatics analysis suggested that this variant may influence the transcriptional capacity of SLC4A7. In summary, our results showed that the SLC4A7 variant, rs4973768, is associated with risk of BC although the underlying biologic mechanism warrants further studies.

Two novel rare variants of APOA5 gene found in subjects with severe hypertriglyceridemia.

Science.gov (United States)

Pisciotta, Livia; Fresa, Raffaele; Bellocchio, Antonella; Guido, Virgilia; Priore Oliva, Claudio; Calandra, Sebastiano; Bertolini, Stefano

2011-11-20

Common variants of APOA5 gene affect plasma triglyceride (TG) in the population and a number of rare variants APOA5 have been reported in individuals with hypertriglyceridemia (HTG). APOA5 was analysed in 98 HTG individuals (plasma TG >9 mmol/L) in whom no mutations in LPL and APOC2 had been found. Two patients were found to be heterozygous for two novel APOA5 variants. The first variant (p.L253P) was identified in an obese male who consumed a diet rich in fat and simple sugars. He was also a carrier in trans of the common TG-raising p.S19W SNP (5*3 haplotype). The second variant (c.295-297 del GAG, p.E99 del) was found in a lean male with no life style or metabolic factors known to affect plasma TG. He was a carrier in trans of the TG-raising 5*2 haplotype and was homozygous for the rare c.1337T allele of a SNP of GCKR gene. No mutations in other genes affecting plasma TG (LMF1 and GPIHBP1) were found in these patients. These APOA5 variants, resulted to be deleterious in silico, were not found in 350 control subjects. These novel APOA5 variants predispose to HTG in combination with other genetic or nutritional factors. Copyright © 2011 Elsevier B.V. All rights reserved.