Hedge fund replication with a genetic algorithm: breeding a usable mousetrap

Czech Academy of Sciences Publication Activity Database

Payne, B. C.; Trešl, Jiří

2015-01-01

Roč. 15, č. 10 (2015), s. 1705-1726 ISSN 1469-7688 R&D Projects: GA ČR(CZ) GA14-31783S Institutional support: RVO:67985998 Keywords : hedge funds * replication * genetic algorithm Subject RIV: AH - Economics Impact factor: 0.794, year: 2015

Common genetic variants on 6q24 associated with exceptional episodic memory performance in the elderly

DEFF Research Database (Denmark)

Barral, Sandra; Cosentino, Stephanie; Christensen, Kaare

2014-01-01

IMPORTANCE: There are genetic influences on memory ability as we age, but no specific genes have been identified. OBJECTIVE: To use a cognitive endophenotype, exceptional episodic memory (EEM) performance, derived from nondemented offspring from the Long Life Family Study (LLFS) to identify genetic...... individuals. Results of the individual replication cohorts were combined by meta-analysis. MAIN OUTCOME MEASURE: Episodic memory scores computed as the mean of the 2 standardized measures of Logical Memory IA and IIA. RESULTS: Heritability estimates indicated a significant genetic component for EEM (h2 = 0...... peak. Replication in one cohort identified a set of 26 SNPs associated with episodic memory (P ≤ .05). Meta-analysis of the 26 SNPs using the 4 independent replication cohorts found SNPs rs9321334 and rs6902875 to be nominally significantly associated with episodic memory (P = .009 and P = .013...

One for all and all for One: Improving replication of genetic studies through network diffusion.

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Daniel Lancour

2018-04-01

Full Text Available Improving accuracy in genetic studies would greatly accelerate understanding the genetic basis of complex diseases. One approach to achieve such an improvement for risk variants identified by the genome wide association study (GWAS approach is to incorporate previously known biology when screening variants across the genome. We developed a simple approach for improving the prioritization of candidate disease genes that incorporates a network diffusion of scores from known disease genes using a protein network and a novel integration with GWAS risk scores, and tested this approach on a large Alzheimer disease (AD GWAS dataset. Using a statistical bootstrap approach, we cross-validated the method and for the first time showed that a network approach improves the expected replication rates in GWAS studies. Several novel AD genes were predicted including CR2, SHARPIN, and PTPN2. Our re-prioritized results are enriched for established known AD-associated biological pathways including inflammation, immune response, and metabolism, whereas standard non-prioritized results were not. Our findings support a strategy of considering network information when investigating genetic risk factors.

Genome-wide association study identifies single nucleotide polymorphism in DYRK1A associated with replication of HIV-1 in monocyte-derived macrophages.

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Sebastiaan M Bol

2011-02-01

Full Text Available HIV-1 infected macrophages play an important role in rendering resting T cells permissive for infection, in spreading HIV-1 to T cells, and in the pathogenesis of AIDS dementia. During highly active anti-retroviral treatment (HAART, macrophages keep producing virus because tissue penetration of antiretrovirals is suboptimal and the efficacy of some is reduced. Thus, to cure HIV-1 infection with antiretrovirals we will also need to efficiently inhibit viral replication in macrophages. The majority of the current drugs block the action of viral enzymes, whereas there is an abundance of yet unidentified host factors that could be targeted. We here present results from a genome-wide association study identifying novel genetic polymorphisms that affect in vitro HIV-1 replication in macrophages.Monocyte-derived macrophages from 393 blood donors were infected with HIV-1 and viral replication was determined using Gag p24 antigen levels. Genomic DNA from individuals with macrophages that had relatively low (n = 96 or high (n = 96 p24 production was used for SNP genotyping with the Illumina 610 Quad beadchip. A total of 494,656 SNPs that passed quality control were tested for association with HIV-1 replication in macrophages, using linear regression. We found a strong association between in vitro HIV-1 replication in monocyte-derived macrophages and SNP rs12483205 in DYRK1A (p = 2.16 × 10(-5. While the association was not genome-wide significant (p<1 × 10(-7, we could replicate this association using monocyte-derived macrophages from an independent group of 31 individuals (p = 0.0034. Combined analysis of the initial and replication cohort increased the strength of the association (p = 4.84 × 10(-6. In addition, we found this SNP to be associated with HIV-1 disease progression in vivo in two independent cohort studies (p = 0.035 and p = 0.0048.These findings suggest that the kinase DYRK1A is involved in the replication of HIV-1, in vitro in macrophages

Replication Validity of Initial Association Studies: A Comparison between Psychiatry, Neurology and Four Somatic Diseases

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Dumas-Mallet, Estelle; Button, Katherine; Boraud, Thomas; Munafo, Marcus; Gonon, François

2016-01-01

Context There are growing concerns about effect size inflation and replication validity of association studies, but few observational investigations have explored the extent of these problems. Objective Using meta-analyses to measure the reliability of initial studies and explore whether this varies across biomedical domains and study types (cognitive/behavioral, brain imaging, genetic and “others”). Methods We analyzed 663 meta-analyses describing associations between markers or risk factors and 12 pathologies within three biomedical domains (psychiatry, neurology and four somatic diseases). We collected the effect size, sample size, publication year and Impact Factor of initial studies, largest studies (i.e., with the largest sample size) and the corresponding meta-analyses. Initial studies were considered as replicated if they were in nominal agreement with meta-analyses and if their effect size inflation was below 100%. Results Nominal agreement between initial studies and meta-analyses regarding the presence of a significant effect was not better than chance in psychiatry, whereas it was somewhat better in neurology and somatic diseases. Whereas effect sizes reported by largest studies and meta-analyses were similar, most of those reported by initial studies were inflated. Among the 256 initial studies reporting a significant effect (p<0.05) and paired with significant meta-analyses, 97 effect sizes were inflated by more than 100%. Nominal agreement and effect size inflation varied with the biomedical domain and study type. Indeed, the replication rate of initial studies reporting a significant effect ranged from 6.3% for genetic studies in psychiatry to 86.4% for cognitive/behavioral studies. Comparison between eight subgroups shows that replication rate decreases with sample size and “true” effect size. We observed no evidence of association between replication rate and publication year or Impact Factor. Conclusion The differences in reliability

Can genetic pleiotropy replicate common clinical constellations of cardiovascular disease and risk?

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Omri Gottesman

Full Text Available The relationship between obesity, diabetes, hyperlipidemia, hypertension, kidney disease and cardiovascular disease (CVD is established when looked at from a clinical, epidemiological or pathophysiological perspective. Yet, when viewed from a genetic perspective, there is comparatively little data synthesis that these conditions have an underlying relationship. We sought to investigate the overlap of genetic variants independently associated with each of these commonly co-existing conditions from the NHGRI genome-wide association study (GWAS catalog, in an attempt to replicate the established notion of shared pathophysiology and risk. We used pathway-based analyses to detect subsets of pleiotropic genes involved in similar biological processes. We identified 107 eligible GWAS studies related to CVD and its established comorbidities and risk factors and assigned genes that correspond to the associated signals based on their position. We found 44 positional genes shared across at least two CVD-related phenotypes that independently recreated the established relationship between the six phenotypes, but only if studies representing non-European populations were included. Seven genes revealed pleiotropy across three or more phenotypes, mostly related to lipid transport and metabolism. Yet, many genes had no relationship to each other or to genes with established functional connection. Whilst we successfully reproduced established relationships between CVD risk factors using GWAS findings, interpretation of biological pathways involved in the observed pleiotropy was limited. Further studies linking genetic variation to gene expression, as well as describing novel biological pathways will be needed to take full advantage of GWAS results.

Genetically Distinct Subsets within ANCA-Associated Vasculitis

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Lyons, Paul A.; Rayner, Tim F.; Trivedi, Sapna; Holle, Julia U.; Watts, Richard A.; Jayne, David R.W.; Baslund, Bo; Brenchley, Paul; Bruchfeld, Annette; Chaudhry, Afzal N.; Tervaert, Jan Willem Cohen; Deloukas, Panos; Feighery, Conleth; Gross, Wolfgang L.; Guillevin, Loic; Gunnarsson, Iva; P, Lorraine Harper M.R.C; Hrušková, Zdenka; Little, Mark A.; Martorana, Davide; Neumann, Thomas; Ohlsson, Sophie; Padmanabhan, Sandosh; Pusey, Charles D.; Salama, Alan D.; Sanders, Jan-Stephan F.; Savage, Caroline O.; Segelmark, Mårten; Stegeman, Coen A.; Tesař, Vladimir; Vaglio, Augusto; Wieczorek, Stefan; Wilde, Benjamin; Zwerina, Jochen; Rees, Andrew J.; Clayton, David G.; Smith, Kenneth G.C.

2013-01-01

BACKGROUND Antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis is a severe condition encompassing two major syndromes: granulomatosis with polyangiitis (formerly known as Wegener’s granulomatosis) and microscopic polyangiitis. Its cause is unknown, and there is debate about whether it is a single disease entity and what role ANCA plays in its pathogenesis. We investigated its genetic basis. METHODS A genomewide association study was performed in a discovery cohort of 1233 U.K. patients with ANCA-associated vasculitis and 5884 controls and was replicated in 1454 Northern European case patients and 1666 controls. Quality control, population stratification, and statistical analyses were performed according to standard criteria. RESULTS We found both major-histocompatibility-complex (MHC) and non-MHC associations with ANCA-associated vasculitis and also that granulomatosis with polyangiitis and microscopic polyangiitis were genetically distinct. The strongest genetic associations were with the antigenic specificity of ANCA, not with the clinical syndrome. Anti–proteinase 3 ANCA was associated with HLA-DP and the genes encoding α1-antitrypsin (SERPINA1) and proteinase 3 (PRTN3) (P = 6.2×10−89, P = 5.6×10−12, and P = 2.6×10−7, respectively). Anti–myeloperoxidase ANCA was associated with HLA-DQ (P = 2.1×10−8). CONCLUSIONS This study confirms that the pathogenesis of ANCA-associated vasculitis has a genetic component, shows genetic distinctions between granulomatosis with polyangiitis and microscopic polyangiitis that are associated with ANCA specificity, and suggests that the response against the autoantigen proteinase 3 is a central pathogenic feature of proteinase 3 ANCA–associated vasculitis. These data provide preliminary support for the concept that proteinase 3 ANCA–associated vasculitis and myeloperoxidase ANCA–associated vasculitis are distinct autoimmune syndromes. (Funded by the British Heart Foundation and others.) PMID

Replication of associations between LRP5 and ESRRA variants and bone density in premenopausal women.

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Giroux, S; Elfassihi, L; Cole, D E C; Rousseau, F

2008-12-01

Replication is a critical step to validate positive genetic associations. In this study, we tested two previously reported positive associations. The low density lipoprotein receptor-related protein 5 (LRP5) Val667Met and lumbar spine bone density are replicated. This result is in line with results from large consortiums such as Genomos. However, the estrogen-related receptor alpha (ESRRA) repeat in the promoter is not replicated although the polymorphism studied was functional and could have been a causative variant. We sought to validate associations previously reported between LRP5 V667M polymorphism and lumbar spine (LS, p = 0.013) and femoral neck (FN, p = 0.0002) bone mineral density (BMD), and between ESRRA 23 base pair repeat polymorphism and LS BMD (p = 0.0036) in a sample of premenopausal Caucasian women using an independent sample. For the replication sample, we recruited 673 premenopausal women from the Toronto metropolitan area. All women were Caucasian and had BMD measured. LRP5 V667M was genotyped by allele-specific PCR and ESRRA repeats by sizing of PCR products on agarose gels. We reproduced the same association as we reported previously between LRP5 V667M and LS BMD (p = 0.015) but not with FN BMD (p = 0.254). The combined data from the two populations indicate an effect size of 0.28SD for LS BMD (p = 0.00048) and an effect size of 0.26 SD for FN BMD (p = 0.00037). In contrast, the association we reported earlier between ESRRA repeats and LS BMD was not replicated in the sample from Toronto (p = 0.645). The association between LRP5 V667M and LS BMD is confirmed but not that between ESRRA repeats and LS BMD. This result indicates that it is imperative to validate any positive association in an independent sample.

Replication Protein A (RPA) Phosphorylation Prevents RPA Association with Replication Centers

OpenAIRE

Vassin, Vitaly M.; Wold, Marc S.; Borowiec, James A.

2004-01-01

Mammalian replication protein A (RPA) undergoes DNA damage-dependent phosphorylation at numerous sites on the N terminus of the RPA2 subunit. To understand the functional significance of RPA phosphorylation, we expressed RPA2 variants in which the phosphorylation sites were converted to aspartate (RPA2D) or alanine (RPA2A). Although RPA2D was incorporated into RPA heterotrimers and supported simian virus 40 DNA replication in vitro, the RPA2D mutant was selectively unable to associate with re...

Genetic Variants Associated with Circulating Parathyroid Hormone.

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Robinson-Cohen, Cassianne; Lutsey, Pamela L; Kleber, Marcus E; Nielson, Carrie M; Mitchell, Braxton D; Bis, Joshua C; Eny, Karen M; Portas, Laura; Eriksson, Joel; Lorentzon, Mattias; Koller, Daniel L; Milaneschi, Yuri; Teumer, Alexander; Pilz, Stefan; Nethander, Maria; Selvin, Elizabeth; Tang, Weihong; Weng, Lu-Chen; Wong, Hoi Suen; Lai, Dongbing; Peacock, Munro; Hannemann, Anke; Völker, Uwe; Homuth, Georg; Nauk, Matthias; Murgia, Federico; Pattee, Jack W; Orwoll, Eric; Zmuda, Joseph M; Riancho, Jose Antonio; Wolf, Myles; Williams, Frances; Penninx, Brenda; Econs, Michael J; Ryan, Kathleen A; Ohlsson, Claes; Paterson, Andrew D; Psaty, Bruce M; Siscovick, David S; Rotter, Jerome I; Pirastu, Mario; Streeten, Elizabeth; März, Winfried; Fox, Caroline; Coresh, Josef; Wallaschofski, Henri; Pankow, James S; de Boer, Ian H; Kestenbaum, Bryan

2017-05-01

Parathyroid hormone (PTH) is a primary calcium regulatory hormone. Elevated serum PTH concentrations in primary and secondary hyperparathyroidism have been associated with bone disease, hypertension, and in some studies, cardiovascular mortality. Genetic causes of variation in circulating PTH concentrations are incompletely understood. We performed a genome-wide association study of serum PTH concentrations among 29,155 participants of European ancestry from 13 cohort studies ( n =22,653 and n =6502 in discovery and replication analyses, respectively). We evaluated the association of single nucleotide polymorphisms (SNPs) with natural log-transformed PTH concentration adjusted for age, sex, season, study site, and principal components of ancestry. We discovered associations of SNPs from five independent regions with serum PTH concentration, including the strongest association with rs6127099 upstream of CYP24A1 ( P =4.2 × 10 -53 ), a gene that encodes the primary catabolic enzyme for 1,25-dihydroxyvitamin D and 25-dihydroxyvitamin D. Each additional copy of the minor allele at this SNP associated with 7% higher serum PTH concentration. The other SNPs associated with serum PTH concentration included rs4074995 within RGS14 ( P =6.6 × 10 -17 ), rs219779 adjacent to CLDN14 ( P =3.5 × 10 -16 ), rs4443100 near RTDR1 ( P =8.7 × 10 -9 ), and rs73186030 near CASR ( P =4.8 × 10 -8 ). Of these five SNPs, rs6127099, rs4074995, and rs219779 replicated. Thus, common genetic variants located near genes involved in vitamin D metabolism and calcium and renal phosphate transport associated with differences in circulating PTH concentrations. Future studies could identify the causal variants at these loci, and the clinical and functional relevance of these variants should be pursued. Copyright © 2017 by the American Society of Nephrology.

QTL replication and targeted association highlight the nerve growth factor gene for nonverbal communication deficits in autism spectrum disorders.

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Lu, A T-H; Yoon, J; Geschwind, D H; Cantor, R M

2013-02-01

Autism Spectrum Disorder (ASD) has a heterogeneous etiology that is genetically complex. It is defined by deficits in communication and social skills and the presence of restricted and repetitive behaviors. Genetic analyses of heritable quantitative traits that correlate with ASD may reduce heterogeneity. With this in mind, deficits in nonverbal communication (NVC) were quantified based on items from the Autism Diagnostic Interview Revised. Our previous analysis of 228 families from the Autism Genetics Research Exchange (AGRE) repository reported 5 potential quantitative trait loci (QTL). Here we report an NVC QTL replication study in an independent sample of 213 AGRE families. One QTL was replicated (Panalysis of 476 haplotype blocks with 708 AGRE families using the Family Based Association Test (FBAT). Blocks in two QTL genes were associated with NVC with a P-value of 0.001. Three associated haplotype blocks were intronic to the Nerve Growth Factor (NGF) gene (P=0.001, 0.001, 0.002), and one was intronic to KCND3 (P=0.001). Individual haplotypes within the associated blocks drove the associations (0.003, 0.0004 and 0.0002) for NGF and 0.0001 for KCND3. Using the same methods, these genes were tested for association with NVC in an independent sample of 1517 families from an Autism Genome Project (AGP). NVC was associated with a haplotype in an adjacent NGF block (P=0.0005) and one 46 kb away from the associated block in KCND3 (0.008). These analyses illustrate the value of QTL and targeted association studies for genetically complex disorders such as ASD. NGF is a promising risk gene for NVC deficits.

Genome-Wide Association Study Identifies Single Nucleotide Polymorphism in DYRK1A Associated with Replication of HIV-1 in Monocyte-Derived Macrophages

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Bol, Sebastiaan M.; Moerland, Perry D.; Limou, Sophie; van Remmerden, Yvonne; Coulonges, Cédric; van Manen, Daniëlle; Herbeck, Joshua T.; Fellay, Jacques; Sieberer, Margit; Sietzema, Jantine G.; van 't Slot, Ruben; Martinson, Jeremy; Zagury, Jean-François; Schuitemaker, Hanneke; van 't Wout, Angélique B.

2011-01-01

Background HIV-1 infected macrophages play an important role in rendering resting T cells permissive for infection, in spreading HIV-1 to T cells, and in the pathogenesis of AIDS dementia. During highly active anti-retroviral treatment (HAART), macrophages keep producing virus because tissue penetration of antiretrovirals is suboptimal and the efficacy of some is reduced. Thus, to cure HIV-1 infection with antiretrovirals we will also need to efficiently inhibit viral replication in macrophages. The majority of the current drugs block the action of viral enzymes, whereas there is an abundance of yet unidentified host factors that could be targeted. We here present results from a genome-wide association study identifying novel genetic polymorphisms that affect in vitro HIV-1 replication in macrophages. Methodology/Principal Findings Monocyte-derived macrophages from 393 blood donors were infected with HIV-1 and viral replication was determined using Gag p24 antigen levels. Genomic DNA from individuals with macrophages that had relatively low (n = 96) or high (n = 96) p24 production was used for SNP genotyping with the Illumina 610 Quad beadchip. A total of 494,656 SNPs that passed quality control were tested for association with HIV-1 replication in macrophages, using linear regression. We found a strong association between in vitro HIV-1 replication in monocyte-derived macrophages and SNP rs12483205 in DYRK1A (p = 2.16×10−5). While the association was not genome-wide significant (p<1×10−7), we could replicate this association using monocyte-derived macrophages from an independent group of 31 individuals (p = 0.0034). Combined analysis of the initial and replication cohort increased the strength of the association (p = 4.84×10−6). In addition, we found this SNP to be associated with HIV-1 disease progression in vivo in two independent cohort studies (p = 0.035 and p = 0.0048). Conclusions/Significance These findings suggest that

Gene ontology analysis of pairwise genetic associations in two genome-wide studies of sporadic ALS

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Kim Nora

2012-07-01

Full Text Available Abstract Background It is increasingly clear that common human diseases have a complex genetic architecture characterized by both additive and nonadditive genetic effects. The goal of the present study was to determine whether patterns of both additive and nonadditive genetic associations aggregate in specific functional groups as defined by the Gene Ontology (GO. Results We first estimated all pairwise additive and nonadditive genetic effects using the multifactor dimensionality reduction (MDR method that makes few assumptions about the underlying genetic model. Statistical significance was evaluated using permutation testing in two genome-wide association studies of ALS. The detection data consisted of 276 subjects with ALS and 271 healthy controls while the replication data consisted of 221 subjects with ALS and 211 healthy controls. Both studies included genotypes from approximately 550,000 single-nucleotide polymorphisms (SNPs. Each SNP was mapped to a gene if it was within 500 kb of the start or end. Each SNP was assigned a p-value based on its strongest joint effect with the other SNPs. We then used the Exploratory Visual Analysis (EVA method and software to assign a p-value to each gene based on the overabundance of significant SNPs at the α = 0.05 level in the gene. We also used EVA to assign p-values to each GO group based on the overabundance of significant genes at the α = 0.05 level. A GO category was determined to replicate if that category was significant at the α = 0.05 level in both studies. We found two GO categories that replicated in both studies. The first, ‘Regulation of Cellular Component Organization and Biogenesis’, a GO Biological Process, had p-values of 0.010 and 0.014 in the detection and replication studies, respectively. The second, ‘Actin Cytoskeleton’, a GO Cellular Component, had p-values of 0.040 and 0.046 in the detection and replication studies, respectively. Conclusions Pathway

Genetic variants of the alpha-synuclein gene SNCA are associated with multiple system atrophy.

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Ammar Al-Chalabi

Full Text Available BACKGROUND: Multiple system atrophy (MSA is a progressive neurodegenerative disorder characterized by parkinsonism, cerebellar ataxia and autonomic dysfunction. Pathogenic mechanisms remain obscure but the neuropathological hallmark is the presence of alpha-synuclein-immunoreactive glial cytoplasmic inclusions. Genetic variants of the alpha-synuclein gene, SNCA, are thus strong candidates for genetic association with MSA. One follow-up to a genome-wide association of Parkinson's disease has identified association of a SNP in SNCA with MSA. METHODOLOGY/FINDINGS: We evaluated 32 SNPs in the SNCA gene in a European population of 239 cases and 617 controls recruited as part of the Neuroprotection and Natural History in Parkinson Plus Syndromes (NNIPPS study. We used 161 independently collected samples for replication. Two SNCA SNPs showed association with MSA: rs3822086 (P = 0.0044, and rs3775444 (P = 0.012, although only the first survived correction for multiple testing. In the MSA-C subgroup the association strengthened despite more than halving the number of cases: rs3822086 P = 0.0024, OR 2.153, (95% CI 1.3-3.6; rs3775444 P = 0.0017, OR 4.386 (95% CI 1.6-11.7. A 7-SNP haplotype incorporating three SNPs either side of rs3822086 strengthened the association with MSA-C further (best haplotype, P = 8.7 x 10(-4. The association with rs3822086 was replicated in the independent samples (P = 0.035. CONCLUSIONS/SIGNIFICANCE: We report a genetic association between MSA and alpha-synuclein which has replicated in independent samples. The strongest association is with the cerebellar subtype of MSA. TRIAL REGISTRATION: ClinicalTrials.gov NCT00211224.

AKT1 fails to replicate as a longevity-associated gene in Danish and German nonagenarians and centenarians

DEFF Research Database (Denmark)

Nygaard, Marianne; Soerensen, Mette; Flachsbart, Friederike

2013-01-01

In addition to APOE and FOXO3, AKT1 has recently been suggested as a third consistent longevity gene, with variants in AKT1 found to be associated with human lifespan in two previous studies. Here, we evaluated AKT1 as a longevity-associated gene across populations by attempting to replicate the ...... not support AKT1 as a universal longevity-associated gene.European Journal of Human Genetics advance online publication, 29 August 2012; doi:10.1038/ejhg.2012.196....

Non-replication of genome-wide based associations between common variants in INSIG2 and PFKP and obesity in studies of 18,014 Danes

DEFF Research Database (Denmark)

Sandholt, Camilla Helene; Mogensen, Mette S; Borch-Johnsen, Knut

2008-01-01

The INSIG2 rs7566605 and PFKP rs6602024 polymorphisms have been identified as obesity gene variants in genome-wide association (GWA) studies. However, replication has been contradictory for both variants. The aims of this study were to validate these obesity-associations through case-control stud......The INSIG2 rs7566605 and PFKP rs6602024 polymorphisms have been identified as obesity gene variants in genome-wide association (GWA) studies. However, replication has been contradictory for both variants. The aims of this study were to validate these obesity-associations through case......-control studies and analyses of obesity-related quantitative traits. Moreover, since environmental and genetic factors may modulate the impact of a genetic variant, we wanted to perform such interaction analyses. We focused on physical activity as an environmental risk factor, and on the GWA identified obesity...

DNA replication and cancer: From dysfunctional replication origin activities to therapeutic opportunities.

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Boyer, Anne-Sophie; Walter, David; Sørensen, Claus Storgaard

2016-06-01

A dividing cell has to duplicate its DNA precisely once during the cell cycle to preserve genome integrity avoiding the accumulation of genetic aberrations that promote diseases such as cancer. A large number of endogenous impacts can challenge DNA replication and cells harbor a battery of pathways to promote genome integrity during DNA replication. This includes suppressing new replication origin firing, stabilization of replicating forks, and the safe restart of forks to prevent any loss of genetic information. Here, we describe mechanisms by which oncogenes can interfere with DNA replication thereby causing DNA replication stress and genome instability. Further, we describe cellular and systemic responses to these insults with a focus on DNA replication restart pathways. Finally, we discuss the therapeutic potential of exploiting intrinsic replicative stress in cancer cells for targeted therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Tests for the replication of an association between Egfr and natural variation in Drosophila melanogaster wing morphology

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Dodgson James

2005-08-01

Full Text Available Abstract Background Quantitative differences between individuals stem from a combination of genetic and environmental factors, with the heritable variation being shaped by evolutionary forces. Drosophila wing shape has emerged as an attractive system for genetic dissection of multi-dimensional traits. We utilize several experimental genetic methods to validation of the contribution of several polymorphisms in the Epidermal growth factor receptor (Egfr gene to wing shape and size, that were previously mapped in populations of Drosophila melanogaster from North Carolina (NC and California (CA. This re-evaluation utilized different genetic testcrosses to generate heterozygous individuals with a variety of genetic backgrounds as well as sampling of new alleles from Kenyan stocks. Results Only one variant, in the Egfr promoter, had replicable effects in all new experiments. However, expanded genotyping of the initial sample of inbred lines rendered the association non-significant in the CA population, while it persisted in the NC sample, suggesting population specific modification of the quantitative trait nucleotide QTN effect. Conclusion Dissection of quantitative trait variation to the nucleotide level can identify sites with replicable effects as small as one percent of the segregating genetic variation. However, the testcross approach to validate QTNs is both labor intensive and time-consuming, and is probably less useful than resampling of large independent sets of outbred individuals.

Replication of SNP associations with keratoconus in a Czech cohort.

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Petra Liskova

Full Text Available Keratoconus is a relatively frequent disease leading to severe visual impairment. Existing therapies are imperfect and clinical management may benefit from improved understanding of mechanisms leading to this disease. We aim to investigate the replication of 11 single nucleotide polymorphisms (SNPs with keratoconus.SNPs from loci previously found in association with keratoconus were genotyped in 165 keratoconus cases of Caucasian Czech origin (108 males and 57 females and 193 population and gender-matched controls. They included rs1536482 (COL5A1, rs4839200 (KCND3, rs757219 and rs214884 (IMMP2L, rs1328083 and rs1328089 (DAOA, rs2721051 (FOXO1, rs4894535 (FNDC3B, rs4954218 (MAP3K19, RAB3GAP1, rs9938149 (ZNF469 and rs1324183 (MPDZ. A case-control association analysis was assessed using Fisher's exact tests.The strongest association was found for rs1324183 (allelic test OR = 1.58; 95% CI, 1.10-2.24, p = 0.01. Statistically significant values were also obtained for rs2721051 (allelic test OR = 1.72; 95% CI, 1.07-2.77, p = 0.025 and rs4954218 (allelic test OR = 1.53; 95% CI, 1.01-2.34; p = 0.047 which showed an opposite effect direction compared to previously reported one.Independent replication of association between two SNPs and keratoconus supports the association of these loci with the risks for the disease development, while the effect of rs4954218 warrants further investigation. Understanding the role of the genetic factors involved in keratoconus etiopathogenesis may facilitate development of novel therapies and an early detection.

Rare genomic structural variants in complex disease: lessons from the replication of associations with obesity.

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Robin G Walters

Full Text Available The limited ability of common variants to account for the genetic contribution to complex disease has prompted searches for rare variants of large effect, to partly explain the 'missing heritability'. Analyses of genome-wide genotyping data have identified genomic structural variants (GSVs as a source of such rare causal variants. Recent studies have reported multiple GSV loci associated with risk of obesity. We attempted to replicate these associations by similar analysis of two familial-obesity case-control cohorts and a population cohort, and detected GSVs at 11 out of 18 loci, at frequencies similar to those previously reported. Based on their reported frequencies and effect sizes (OR≥25, we had sufficient statistical power to detect the large majority (80% of genuine associations at these loci. However, only one obesity association was replicated. Deletion of a 220 kb region on chromosome 16p11.2 has a carrier population frequency of 2×10(-4 (95% confidence interval [9.6×10(-5-3.1×10(-4]; accounts overall for 0.5% [0.19%-0.82%] of severe childhood obesity cases (P = 3.8×10(-10; odds ratio = 25.0 [9.9-60.6]; and results in a mean body mass index (BMI increase of 5.8 kg.m(-2 [1.8-10.3] in adults from the general population. We also attempted replication using BMI as a quantitative trait in our population cohort; associations with BMI at or near nominal significance were detected at two further loci near KIF2B and within FOXP2, but these did not survive correction for multiple testing. These findings emphasise several issues of importance when conducting rare GSV association, including the need for careful cohort selection and replication strategy, accurate GSV identification, and appropriate correction for multiple testing and/or control of false discovery rate. Moreover, they highlight the potential difficulty in replicating rare CNV associations across different populations. Nevertheless, we show that such studies are potentially

Genome-wide association scan shows genetic variants in the FTO gene are associated with obesity-related traits.

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Angelo Scuteri

2007-07-01

Full Text Available The obesity epidemic is responsible for a substantial economic burden in developed countries and is a major risk factor for type 2 diabetes and cardiovascular disease. The disease is the result not only of several environmental risk factors, but also of genetic predisposition. To take advantage of recent advances in gene-mapping technology, we executed a genome-wide association scan to identify genetic variants associated with obesity-related quantitative traits in the genetically isolated population of Sardinia. Initial analysis suggested that several SNPs in the FTO and PFKP genes were associated with increased BMI, hip circumference, and weight. Within the FTO gene, rs9930506 showed the strongest association with BMI (p = 8.6 x10(-7, hip circumference (p = 3.4 x 10(-8, and weight (p = 9.1 x 10(-7. In Sardinia, homozygotes for the rare "G" allele of this SNP (minor allele frequency = 0.46 were 1.3 BMI units heavier than homozygotes for the common "A" allele. Within the PFKP gene, rs6602024 showed very strong association with BMI (p = 4.9 x 10(-6. Homozygotes for the rare "A" allele of this SNP (minor allele frequency = 0.12 were 1.8 BMI units heavier than homozygotes for the common "G" allele. To replicate our findings, we genotyped these two SNPs in the GenNet study. In European Americans (N = 1,496 and in Hispanic Americans (N = 839, we replicated significant association between rs9930506 in the FTO gene and BMI (p-value for meta-analysis of European American and Hispanic American follow-up samples, p = 0.001, weight (p = 0.001, and hip circumference (p = 0.0005. We did not replicate association between rs6602024 and obesity-related traits in the GenNet sample, although we found that in European Americans, Hispanic Americans, and African Americans, homozygotes for the rare "A" allele were, on average, 1.0-3.0 BMI units heavier than homozygotes for the more common "G" allele. In summary, we have completed a whole genome-association scan for

Molecular genetic analysis of a vaccinia virus gene with an essential role in DNA replication

International Nuclear Information System (INIS)

Evans, E.V.A.

1989-01-01

The poxvirus, vaccinia, is large DNA virus which replicates in the cytoplasma of the host cell. The virus is believed to encode most or all of the functions required for the temporally regulated transcription and replication of its 186 kilobase genome. Physical and genetic autonomy from the host make vaccinia a useful eukaryotic organism in which to study replication genes and proteins, using a combination of biochemical and genetic techniques. Essential viral functions for replication are identified by conditional lethal mutants that fail to synthesize DNA at the non-permissive temperatures. One such group contains the non-complementing alleles ts17, ts24, ts69 (WR strain). Studies were undertaken to define the phenotype of ts mutants, and to identify and characterize the affected gene and protein. Mutant infection was essentially normal at 32 degree C, but at 39 degree C the mutants did not incorporate 3 H-thymidine into nascent viral DNA or synthesize late viral proteins. If mutant cultures were shifted to non-permissive conditions at the height of replication, DNA synthesis was halted rapidly, implying that the mutants are defective in DNA elongation. The gene affected in the WR mutants and in ts6389, a DNA-minus mutant of the IHD strain, was mapped by marker rescue and corresponds to open reading frame 5 (orfD5) of the viral HindIII D fragment

Success and failure in replication of genotype-phenotype associations: How does replication help in understanding the genetic basis of phenotypic variation in outbred populations?

Science.gov (United States)

Schielzeth, Holger; Rios Villamil, Alejandro; Burri, Reto

2018-03-25

Recent developments in sequencing technologies have facilitated genomewide mapping of phenotypic variation in natural populations. Such mapping efforts face a number of challenges potentially leading to low reproducibility. However, reproducible research forms the basis of scientific progress. We here discuss the options for replication and the reasons for potential nonreproducibility. We then review the evidence for reproducible quantitative trait loci (QTL) with a focus on natural animal populations. Existing case studies of replication fall into three categories: (i) traits that have been mapped to major effect loci (including chromosomal inversion and supergenes) by independent research teams; (ii) QTL fine-mapped in discovery populations; and (iii) attempts to replicate QTL across multiple populations. Major effect loci, in particular those associated with inversions, have been successfully replicated in several cases within and across populations. Beyond such major effect variants, replication has been more successful within than across populations, suggesting that QTL discovered in natural populations may often be population-specific. This suggests that biological causes (differences in linkage patterns, allele frequencies or context-dependencies of QTL) contribute to nonreproducibility. Evidence from other fields, notably animal breeding and QTL mapping in humans, suggests that a significant fraction of QTL is indeed reproducible in direction and magnitude at least within populations. However, there is also a large number of QTL that cannot be easily reproduced. We put forward that more studies should explicitly address the causes and context-dependencies of QTL signals, in particular to disentangle linkage differences, allele frequency differences and gene-by-environment interactions as biological causes of nonreproducibility of QTL, especially between populations. © 2018 John Wiley & Sons Ltd.

Identification, replication, and fine-mapping of Loci associated with adult height in individuals of african ancestry.

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Amidou N'Diaye

2011-10-01

Full Text Available Adult height is a classic polygenic trait of high heritability (h(2 approximately 0.8. More than 180 single nucleotide polymorphisms (SNPs, identified mostly in populations of European descent, are associated with height. These variants convey modest effects and explain approximately10% of the variance in height. Discovery efforts in other populations, while limited, have revealed loci for height not previously implicated in individuals of European ancestry. Here, we performed a meta-analysis of genome-wide association (GWA results for adult height in 20,427 individuals of African ancestry with replication in up to 16,436 African Americans. We found two novel height loci (Xp22-rs12393627, P = 3.4×10(-12 and 2p14-rs4315565, P = 1.2×10(-8. As a group, height associations discovered in European-ancestry samples replicate in individuals of African ancestry (P = 1.7×10(-4 for overall replication. Fine-mapping of the European height loci in African-ancestry individuals showed an enrichment of SNPs that are associated with expression of nearby genes when compared to the index European height SNPs (P<0.01. Our results highlight the utility of genetic studies in non-European populations to understand the etiology of complex human diseases and traits.

Genetics in psychiatry: common variant association studies

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Buxbaum Joseph D

2010-03-01

Full Text Available Abstract Many psychiatric conditions and traits are associated with significant heritability. Genetic risk for psychiatric conditions encompass rare variants, identified due to major effect, as well as common variants, the latter analyzed by association analyses. We review guidelines for common variant association analyses, undertaking after assessing evidence of heritability. We highlight the importance of: suitably large sample sizes; an experimental design that controls for ancestry; careful data cleaning; correction for multiple testing; small P values for positive findings; assessment of effect size for positive findings; and, inclusion of an independent replication sample. We also note the importance of a critical discussion of any prior findings, biological follow-up where possible, and a means of accessing the raw data.

Genetic recombination in escherichia coli and its relationship with DNA replication

International Nuclear Information System (INIS)

Siddiqui, O.

1974-01-01

Relationship of DNA replication with genetic recombination in Escherichia Coli was investigated by mating Hfr donors labelled with H 3 -thymine, C 13 and N 15 to C 13 N 15 labelled recipients. The DNA extracted from the zygotes was analysed on CsCl density gradients. The results show that all of the biparentally labelled DNA arises from the single strand insertions of the donor DNA. (M.G.B.)

The Idea Is Good, but…: Failure to Replicate Associations of Oxytocinergic Polymorphisms with Face-Inversion in the N170.

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Aisha J L Munk

Full Text Available In event-related potentials, the N170 manifests itself especially in reaction to faces. In the healthy population, face-inversion leads to stronger negative amplitudes and prolonged latencies of the N170, effects not being present in patients with autism-spectrum-disorder (ASD. ASD has frequently been associated with differences in oxytocinergic neurotransmission. This ERP-study aimed to investigate the face-inversion effect in association with oxytocinergic candidate genes. It was expected that risk-allele-carriers of the oxytocin-receptor-gene-polymorphism (rs53576 and of CD38 (rs379863 responded similar to upright and inverted faces as persons with ASD. Additionally, reactions to different facial emotional expressions were studied. As there have been difficulties with replications of those molecular genetic association studies, we aimed to replicate our findings in a second study.Seventy-two male subjects in the first-, and seventy-eight young male subjects in the replication-study conducted a face-inversion-paradigm, while recording EEG. DNA was extracted from buccal cells.Results revealed stronger N170-amplitudes and longer latencies in reaction to inverted faces in comparison to upright ones. Furthermore, effects of emotion on N170 were evident. Those effects were present in the first and in the second study. Whereas we found molecular-genetic associations of oxytocinergic polymorphisms with the N170 in the first study, we failed to do so in the replication sample.Results indicate that a deeper theoretical understanding of this research-field is needed, in order to generate possible explanations for these findings. Results, furthermore, support the hypotheses that success of reproducibility is correlated with strength of lower original p-values and larger effect sizes in the original study.

DNA Copy-Number Control through Inhibition of Replication Fork Progression

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Jared T. Nordman

2014-11-01

Full Text Available Proper control of DNA replication is essential to ensure faithful transmission of genetic material and prevent chromosomal aberrations that can drive cancer progression and developmental disorders. DNA replication is regulated primarily at the level of initiation and is under strict cell-cycle regulation. Importantly, DNA replication is highly influenced by developmental cues. In Drosophila, specific regions of the genome are repressed for DNA replication during differentiation by the SNF2 domain-containing protein SUUR through an unknown mechanism. We demonstrate that SUUR is recruited to active replication forks and mediates the repression of DNA replication by directly inhibiting replication fork progression instead of functioning as a replication fork barrier. Mass spectrometry identification of SUUR-associated proteins identified the replicative helicase member CDC45 as a SUUR-associated protein, supporting a role for SUUR directly at replication forks. Our results reveal that control of eukaryotic DNA copy number can occur through the inhibition of replication fork progression.

Replicating animal mitochondrial DNA

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Emily A. McKinney

2013-01-01

Full Text Available The field of mitochondrial DNA (mtDNA replication has been experiencing incredible progress in recent years, and yet little is certain about the mechanism(s used by animal cells to replicate this plasmid-like genome. The long-standing strand-displacement model of mammalian mtDNA replication (for which single-stranded DNA intermediates are a hallmark has been intensively challenged by a new set of data, which suggests that replication proceeds via coupled leading-and lagging-strand synthesis (resembling bacterial genome replication and/or via long stretches of RNA intermediates laid on the mtDNA lagging-strand (the so called RITOLS. The set of proteins required for mtDNA replication is small and includes the catalytic and accessory subunits of DNA polymerase y, the mtDNA helicase Twinkle, the mitochondrial single-stranded DNA-binding protein, and the mitochondrial RNA polymerase (which most likely functions as the mtDNA primase. Mutations in the genes coding for the first three proteins are associated with human diseases and premature aging, justifying the research interest in the genetic, biochemical and structural properties of the mtDNA replication machinery. Here we summarize these properties and discuss the current models of mtDNA replication in animal cells.

Polymorphisms in RYBP and AOAH genes are associated with chronic rhinosinusitis in a Chinese population: a replication study.

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Yuan Zhang

Full Text Available BACKGROUND: The development of CRS is believed to be the result of combined interactions between the genetic background of the affected subject and environmental factors. OBJECTIVES: To replicate and extend our recent findings from genetic association studies in chronic rhinosinusitis (CRS performed in a Canadian Caucasian population in a Chinese population. METHODS: In a case-control replication study, DNA samples were obtained from CRS with (n  = 306; CRSwNP and without (n = 332; CRSsNP nasal polyps, and controls (n = 315 in a Chinese population. A total of forty-nine single nucleotide polymorphisms (SNPs selected from previous identified SNPs associated with CRS in Canadian population, and SNPs from the CHB HapMap dataset were individually genotyped. RESULTS: We identified two SNPs respectively in RYBP (rs4532099, p = 2.15E-06, OR = 2.59 and AOAH (rs4504543, p = 0.0001152, OR = 0.58 significantly associated with whole CRS cohort. Subgroup analysis for the presence of nasal polyps (CRSwNP and CRSsNP displayed significant association in CRSwNP cohorts regarding to one SNP in RYBP (P = 3.24(E-006, OR = 2.76. Evidence of association in the CRSsNP groups in terms of 2 SNPs (AOAH_rs4504543 and RYBP_rs4532099 was detected as well. Stratifying analysis by gender demonstrated that none of the selected SNPs were associated with CRSwNP as well as CRSsNP. Meanwhile 3 SNPs (IL1A_rs17561, P = 0.005778; IL1A_rs1800587, P = 0.009561; IRAK4_rs4251513, P = 0.03837 were associated with serum total IgE level. CONCLUSIONS: These genes are biologically plausible, with roles in regulation of transcription (RYBP and inflammatory response (AOAH. The present data suggests the potential common genetic basis in the development of CRS in Chinese and Caucasian population.

Associations between Salivary Testosterone Levels, Androgen‐Related Genetic Polymorphisms, and Self‐Estimated Ejaculation Latency Time

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Patrick Jern, PhD

2014-08-01

Conclusions: We were unable to find support for the hypothesis suggesting an association between T levels and ELT, possibly because of the low number of phenotypically extreme cases (the sample used in the present study was population based. Our results concerning genetic associations should be interpreted with caution until replication studies have been conducted. Jern P, Westberg L, Ankarberg‐Lindgren C, Johansson A, Gunst A, Sandnabba NK, and Santtila P. Associations between salivary testosterone levels, androgen‐related genetic polymorphisms, and self‐estimated ejaculation latency time. Sex Med 2014;2:107–114.

Lack of replication for the myosin-18B association with mathematical ability in independent cohorts.

Science.gov (United States)

Pettigrew, K A; Fajutrao Valles, S F; Moll, K; Northstone, K; Ring, S; Pennell, C; Wang, C; Leavett, R; Hayiou-Thomas, M E; Thompson, P; Simpson, N H; Fisher, S E; Whitehouse, A J O; Snowling, M J; Newbury, D F; Paracchini, S

2015-04-01

Twin studies indicate that dyscalculia (or mathematical disability) is caused partly by a genetic component, which is yet to be understood at the molecular level. Recently, a coding variant (rs133885) in the myosin-18B gene was shown to be associated with mathematical abilities with a specific effect among children with dyslexia. This association represents one of the most significant genetic associations reported to date for mathematical abilities and the only one reaching genome-wide statistical significance. We conducted a replication study in different cohorts to assess the effect of rs133885 maths-related measures. The study was conducted primarily using the Avon Longitudinal Study of Parents and Children (ALSPAC), (N = 3819). We tested additional cohorts including the York Cohort, the Specific Language Impairment Consortium (SLIC) cohort and the Raine Cohort, and stratified them for a definition of dyslexia whenever possible. We did not observe any associations between rs133885 in myosin-18B and mathematical abilities among individuals with dyslexia or in the general population. Our results suggest that the myosin-18B variant is unlikely to be a main factor contributing to mathematical abilities. © 2015 The Authors. Genes, Brain and Behavior published by International Behavioural and Neural Genetics Society and John Wiley & Sons Ltd.

Genetic exchanges caused by ultraviolet photoproducts in phage lamda DNA molecules: the role of DNA replication

International Nuclear Information System (INIS)

Lin, P.F.; Howard-Flanders, P.; Yale Univ., New Haven, Conn.

1976-01-01

Genetic recombination induced by structural damage in DNA molecules was investigated in E. coli K12(lamda) lysogens infected with genetically marked phage lamda. Photoproducts were induced in the phage DNA before infection by exposing them either to 313 nm light in the presence of acetophenone or to 254 nm light. To test the role of the replication of the damage phage DNA on the frequency of the induced recombination , both heteroimmune and homoimmune crosses were performed, and scored for P + recombinants. In heteroimmune crosses, recombination was less frequent in infected cells exposed to visible light and in wild type cells able to perform excision repair than in excision-defective lysogens. Therefore, much of the induced recombination can be attributed to the pyrimidine dimers in the phage DNA. In homoimmune crosses, replication of the phage DNA containing ultraviolet photoproducts was represented by lamda immunity, and was further blocked by the lack of the P gene product needed for replication. The 254 nm photoproducts increased the frequency of recombination in these homoimmune crosses, even though phage DNA replication was blocked. Irradiation with 313 nm light and acetophenone M, which produces dimers and unknown photoproducts, was not as effective per dimer as the 254 nm light. It is concluded from these results that certain unidentified 254 nm photoproducts can cause recombination even in the absence of DNA replication. They are not pyrimidine dimers, as they are not susceptible to excision repair or photoreactivation. In contrast, pyrimidine dimers appear to cause recombination only when the DNA containing them undergoes replication. (orig./MG) [de

Genome-wide association study identifies genetic loci associated with iron deficiency.

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Christine E McLaren

2011-03-01

Full Text Available The existence of multiple inherited disorders of iron metabolism in man, rodents and other vertebrates suggests genetic contributions to iron deficiency. To identify new genomic locations associated with iron deficiency, a genome-wide association study (GWAS was performed using DNA collected from white men aged≥25 y and women≥50 y in the Hemochromatosis and Iron Overload Screening (HEIRS Study with serum ferritin (SF≤12 µg/L (cases and iron replete controls (SF>100 µg/L in men, SF>50 µg/L in women. Regression analysis was used to examine the association between case-control status (336 cases, 343 controls and quantitative serum iron measures and 331,060 single nucleotide polymorphism (SNP genotypes, with replication analyses performed in a sample of 71 cases and 161 controls from a population of white male and female veterans screened at a US Veterans Affairs (VA medical center. Five SNPs identified in the GWAS met genome-wide statistical significance for association with at least one iron measure, rs2698530 on chr. 2p14; rs3811647 on chr. 3q22, a known SNP in the transferrin (TF gene region; rs1800562 on chr. 6p22, the C282Y mutation in the HFE gene; rs7787204 on chr. 7p21; and rs987710 on chr. 22q11 (GWAS observed P<1.51×10(-7 for all. An association between total iron binding capacity and SNP rs3811647 in the TF gene (GWAS observed P=7.0×10(-9, corrected P=0.012 was replicated within the VA samples (observed P=0.012. Associations with the C282Y mutation in the HFE gene also were replicated. The joint analysis of the HEIRS and VA samples revealed strong associations between rs2698530 on chr. 2p14 and iron status outcomes. These results confirm a previously-described TF polymorphism and implicate one potential new locus as a target for gene identification.

Power assessment for genetic association study of human longevity using offspring of long-lived subjects

DEFF Research Database (Denmark)

Tan, Qihua; Zhao, Jing Hua; Li, Shuxia

2010-01-01

and the proportional hazard model for generating individual lifespan. Family genotype data is generated using a genetic linkage program for given SNP allele frequency. Power is estimated by setting the type I error rate at 0.05 and by calculating the Armitage's chi-squared test statistic for 200 replicate samples...... the direct approach. It also has low power in detecting non-additive effect genes. Indirect genetic association using offspring from families with both parents as nonagenarians is nearly as powerful as using offspring from families with one centenarian parent. In conclusion, the indirect design can be a good......Recently, an indirect genetic association approach that compares genotype frequencies in offspring of long-lived subjects and offspring from random families has been introduced to study gene-longevity associations. Although the indirect genetic association has certain advantages over the direct...

Climate variables explain neutral and adaptive variation within salmonid metapopulations: The importance of replication in landscape genetics

Science.gov (United States)

Hand, Brian K.; Muhlfeld, Clint C.; Wade, Alisa A.; Kovach, Ryan; Whited, Diane C.; Narum, Shawn R.; Matala, Andrew P.; Ackerman, Michael W.; Garner, B. A.; Kimball, John S; Stanford, Jack A.; Luikart, Gordon

2016-01-01

Understanding how environmental variation influences population genetic structure is important for conservation management because it can reveal how human stressors influence population connectivity, genetic diversity and persistence. We used riverscape genetics modelling to assess whether climatic and habitat variables were related to neutral and adaptive patterns of genetic differentiation (population-specific and pairwise FST) within five metapopulations (79 populations, 4583 individuals) of steelhead trout (Oncorhynchus mykiss) in the Columbia River Basin, USA. Using 151 putatively neutral and 29 candidate adaptive SNP loci, we found that climate-related variables (winter precipitation, summer maximum temperature, winter highest 5% flow events and summer mean flow) best explained neutral and adaptive patterns of genetic differentiation within metapopulations, suggesting that climatic variation likely influences both demography (neutral variation) and local adaptation (adaptive variation). However, we did not observe consistent relationships between climate variables and FST across all metapopulations, underscoring the need for replication when extrapolating results from one scale to another (e.g. basin-wide to the metapopulation scale). Sensitivity analysis (leave-one-population-out) revealed consistent relationships between climate variables and FST within three metapopulations; however, these patterns were not consistent in two metapopulations likely due to small sample sizes (N = 10). These results provide correlative evidence that climatic variation has shaped the genetic structure of steelhead populations and highlight the need for replication and sensitivity analyses in land and riverscape genetics.

Regulation of beta cell replication

DEFF Research Database (Denmark)

Lee, Ying C; Nielsen, Jens Høiriis

2008-01-01

Beta cell mass, at any given time, is governed by cell differentiation, neogenesis, increased or decreased cell size (cell hypertrophy or atrophy), cell death (apoptosis), and beta cell proliferation. Nutrients, hormones and growth factors coupled with their signalling intermediates have been...... suggested to play a role in beta cell mass regulation. In addition, genetic mouse model studies have indicated that cyclins and cyclin-dependent kinases that determine cell cycle progression are involved in beta cell replication, and more recently, menin in association with cyclin-dependent kinase...... inhibitors has been demonstrated to be important in beta cell growth. In this review, we consider and highlight some aspects of cell cycle regulation in relation to beta cell replication. The role of cell cycle regulation in beta cell replication is mostly from studies in rodent models, but whether...

Genetic Variation in NFKBIE Is Associated With Increased Risk of Pneumococcal Meningitis in Children

DEFF Research Database (Denmark)

Lundbo, Lene F; Harboe, Zitta Barrella; Clausen, Louise N

2016-01-01

NFKBIA, NFKBIE and NFKBIZ. We aimed to replicate previous findings of genetic variation associated with invasive pneumococcal disease (IPD), and to assess whether similar associations could be found in invasive meningococcal disease (IMD). METHODS: Cases with IPD and IMD and controls were identified......BACKGROUND: Streptococcus pneumoniae and Neisseria meningitidis are frequent pathogens in life-threatening infections. Genetic variation in the immune system may predispose to these infections. Nuclear factor-κB is a key component of the TLR-pathway, controlled by inhibitors, encoded by the genes.......86-1.35). The remaining SNPs were not associated with susceptibility to invasive disease. None of the SNPs were associated with risk of IMD or mortality. CONCLUSIONS: A NFKBIE polymorphism was associated with increased risk of pneumococcal meningitis....

Heritability and confirmation of genetic association studies for childhood asthma in twins.

Science.gov (United States)

Ullemar, V; Magnusson, P K E; Lundholm, C; Zettergren, A; Melén, E; Lichtenstein, P; Almqvist, C

2016-02-01

Although the genetics of asthma has been extensively studied using both quantitative and molecular genetic analysis methods, both approaches lack studies specific to the childhood phenotype and including other allergic diseases. This study aimed to give specific estimates for the heritability of childhood asthma and other allergic diseases, to attempt to replicate findings from genomewide association studies (GWAS) for childhood asthma and to test the same variants against other allergic diseases. In a cohort of 25 306 Swedish twins aged 9 or 12 years, data on asthma were available from parental interviews and population-based registers. The interviews also inquired about wheeze, hay fever, eczema, and food allergy. Through structural equation modeling, the heritability of all phenotypes was calculated. A subset of 10 075 twins was genotyped for 16 single nucleotide polymorphisms (SNPs) selected from previous GWAS; these were first tested for association with asthma and significant findings also against the other allergic diseases. The heritability of any childhood asthma was 0.82 (95% CI 0.79-0.85). For the other allergic diseases, the range was approximately 0.60-0.80. Associations for six SNPs with asthma were replicated, including rs2305480 in the GSDMB gene (OR 0.80, 95% CI 0.74-0.86, P = 1.5*10(-8) ; other significant associations all below P = 3.5*10(-4) ). Of these, only rs3771180 in IL1RL1 was associated with any other allergic disease (for hay fever, OR 0.64, 95% CI 0.53-0.77, P = 2.5*10(-6) ). Asthma and allergic diseases of childhood are highly heritable, and these high-risk genetic variants associated specifically with childhood asthma, except for one SNP shared with hay fever. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Lack of replication for the myosin-18B association with mathematical ability in independent cohorts

Science.gov (United States)

Pettigrew, K A; Fajutrao Valles, S F; Moll, K; Northstone, K; Ring, S; Pennell, C; Wang, C; Leavett, R; Hayiou-Thomas, M E; Thompson, P; Simpson, N H; Fisher, S E; Whitehouse, A J O; Snowling, M J; Newbury, D F; Paracchini, S

2015-01-01

Twin studies indicate that dyscalculia (or mathematical disability) is caused partly by a genetic component, which is yet to be understood at the molecular level. Recently, a coding variant (rs133885) in the myosin-18B gene was shown to be associated with mathematical abilities with a specific effect among children with dyslexia. This association represents one of the most significant genetic associations reported to date for mathematical abilities and the only one reaching genome-wide statistical significance. We conducted a replication study in different cohorts to assess the effect of rs133885 maths-related measures. The study was conducted primarily using the Avon Longitudinal Study of Parents and Children (ALSPAC), (N = 3819). We tested additional cohorts including the York Cohort, the Specific Language Impairment Consortium (SLIC) cohort and the Raine Cohort, and stratified them for a definition of dyslexia whenever possible. We did not observe any associations between rs133885 in myosin-18B and mathematical abilities among individuals with dyslexia or in the general population. Our results suggest that the myosin-18B variant is unlikely to be a main factor contributing to mathematical abilities. PMID:25778778

Reverse Genetics System Demonstrates that Rotavirus Nonstructural Protein NSP6 Is Not Essential for Viral Replication in Cell Culture.

Science.gov (United States)

Komoto, Satoshi; Kanai, Yuta; Fukuda, Saori; Kugita, Masanori; Kawagishi, Takahiro; Ito, Naoto; Sugiyama, Makoto; Matsuura, Yoshiharu; Kobayashi, Takeshi; Taniguchi, Koki

2017-11-01

The use of overlapping open reading frames (ORFs) to synthesize more than one unique protein from a single mRNA has been described for several viruses. Segment 11 of the rotavirus genome encodes two nonstructural proteins, NSP5 and NSP6. The NSP6 ORF is present in the vast majority of rotavirus strains, and therefore the NSP6 protein would be expected to have a function in viral replication. However, there is no direct evidence of its function or requirement in the viral replication cycle yet. Here, taking advantage of a recently established plasmid-only-based reverse genetics system that allows rescue of recombinant rotaviruses entirely from cloned cDNAs, we generated NSP6-deficient viruses to directly address its significance in the viral replication cycle. Viable recombinant NSP6-deficient viruses could be engineered. Single-step growth curves and plaque formation of the NSP6-deficient viruses confirmed that NSP6 expression is of limited significance for RVA replication in cell culture, although the NSP6 protein seemed to promote efficient virus growth. IMPORTANCE Rotavirus is one of the most important pathogens of severe diarrhea in young children worldwide. The rotavirus genome, consisting of 11 segments of double-stranded RNA, encodes six structural proteins (VP1 to VP4, VP6, and VP7) and six nonstructural proteins (NSP1 to NSP6). Although specific functions have been ascribed to each of the 12 viral proteins, the role of NSP6 in the viral replication cycle remains unknown. In this study, we demonstrated that the NSP6 protein is not essential for viral replication in cell culture by using a recently developed plasmid-only-based reverse genetics system. This reverse genetics approach will be successfully applied to answer questions of great interest regarding the roles of rotaviral proteins in replication and pathogenicity, which can hardly be addressed by conventional approaches. Copyright © 2017 American Society for Microbiology.

Replication of LDL GWAs hits in PROSPER/PHASE as validation for future (pharmaco)genetic analyses

LENUS (Irish Health Repository)

Trompet, Stella

2011-10-06

Abstract Background The PHArmacogenetic study of Statins in the Elderly at risk (PHASE) is a genome wide association study in the PROspective Study of Pravastatin in the Elderly at risk for vascular disease (PROSPER) that investigates the genetic variation responsible for the individual variation in drug response to pravastatin. Statins lower LDL-cholesterol in general by 30%, however not in all subjects. Moreover, clinical response is highly variable and adverse effects occur in a minority of patients. In this report we first describe the rationale of the PROSPER\\/PHASE project and second show that the PROSPER\\/PHASE study can be used to study pharmacogenetics in the elderly. Methods The genome wide association study (GWAS) was conducted using the Illumina 660K-Quad beadchips following manufacturer\\'s instructions. After a stringent quality control 557,192 SNPs in 5,244 subjects were available for analysis. To maximize the availability of genetic data and coverage of the genome, imputation up to 2.5 million autosomal CEPH HapMap SNPs was performed with MACH imputation software. The GWAS for LDL-cholesterol is assessed with an additive linear regression model in PROBABEL software, adjusted for age, sex, and country of origin to account for population stratification. Results Forty-two SNPs reached the GWAS significant threshold of p = 5.0e-08 in 5 genomic loci (APOE\\/APOC1; LDLR; FADS2\\/FEN1; HMGCR; PSRC1\\/CELSR5). The top SNP (rs445925, chromosome 19) with a p-value of p = 2.8e-30 is located within the APOC1 gene and near the APOE gene. The second top SNP (rs6511720, chromosome 19) with a p-value of p = 5.22e-15 is located within the LDLR gene. All 5 genomic loci were previously associated with LDL-cholesterol levels, no novel loci were identified. Replication in WOSCOPS and CARE confirmed our results. Conclusion With the GWAS in the PROSPER\\/PHASE study we confirm the previously found genetic associations with LDL-cholesterol levels. With this proof

GWAS of 126,559 Individuals Identifies Genetic Variants Associated with Educational Attainment

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Rietveld, Cornelius A.; Medland, Sarah E.; Derringer, Jaime; Yang, Jian; Esko, Tõnu; Martin, Nicolas W.; Westra, Harm-Jan; Shakhbazov, Konstantin; Abdellaoui, Abdel; Agrawal, Arpana; Albrecht, Eva; Alizadeh, Behrooz Z.; Amin, Najaf; Barnard, John; Baumeister, Sebastian E.; Benke, Kelly S.; Bielak, Lawrence F.; Boatman, Jeffrey A.; Boyle, Patricia A.; Davies, Gail; de Leeuw, Christiaan; Eklund, Niina; Evans, Daniel S.; Ferhmann, Rudolf; Fischer, Krista; Gieger, Christian; Gjessing, Håkon K.; Hägg, Sara; Harris, Jennifer R.; Hayward, Caroline; Holzapfel, Christina; Ibrahim-Verbaas, Carla A.; Ingelsson, Erik; Jacobsson, Bo; Joshi, Peter K.; Jugessur, Astanand; Kaakinen, Marika; Kanoni, Stavroula; Karjalainen, Juha; Kolcic, Ivana; Kristiansson, Kati; Kutalik, Zoltán; Lahti, Jari; Lee, Sang H.; Lin, Peng; Lind, Penelope A.; Liu, Yongmei; Lohman, Kurt; Loitfelder, Marisa; McMahon, George; Vidal, Pedro Marques; Meirelles, Osorio; Milani, Lili; Myhre, Ronny; Nuotio, Marja-Liisa; Oldmeadow, Christopher J.; Petrovic, Katja E.; Peyrot, Wouter J.; Polašek, Ozren; Quaye, Lydia; Reinmaa, Eva; Rice, John P.; Rizzi, Thais S.; Schmidt, Helena; Schmidt, Reinhold; Smith, Albert V.; Smith, Jennifer A.; Tanaka, Toshiko; Terracciano, Antonio; van der Loos, Matthijs J.H.M.; Vitart, Veronique; Völzke, Henry; Wellmann, Jürgen; Yu, Lei; Zhao, Wei; Allik, Jüri; Attia, John R.; Bandinelli, Stefania; Bastardot, François; Beauchamp, Jonathan; Bennett, David A.; Berger, Klaus; Bierut, Laura J.; Boomsma, Dorret I.; Bültmann, Ute; Campbell, Harry; Chabris, Christopher F.; Cherkas, Lynn; Chung, Mina K.; Cucca, Francesco; de Andrade, Mariza; De Jager, Philip L.; De Neve, Jan-Emmanuel; Deary, Ian J.; Dedoussis, George V.; Deloukas, Panos; Dimitriou, Maria; Eiriksdottir, Gudny; Elderson, Martin F.; Eriksson, Johan G.; Evans, David M.; Faul, Jessica D.; Ferrucci, Luigi; Garcia, Melissa E.; Grönberg, Henrik; Gudnason, Vilmundur; Hall, Per; Harris, Juliette M.; Harris, Tamara B.; Hastie, Nicholas D.; Heath, Andrew C.; Hernandez, Dena G.; Hoffmann, Wolfgang; Hofman, Adriaan; Holle, Rolf; Holliday, Elizabeth G.; Hottenga, Jouke-Jan; Iacono, William G.; Illig, Thomas; Järvelin, Marjo-Riitta; Kähönen, Mika; Kaprio, Jaakko; Kirkpatrick, Robert M.; Kowgier, Matthew; Latvala, Antti; Launer, Lenore J.; Lawlor, Debbie A.; Lehtimäki, Terho; Li, Jingmei; Lichtenstein, Paul; Lichtner, Peter; Liewald, David C.; Madden, Pamela A.; Magnusson, Patrik K. E.; Mäkinen, Tomi E.; Masala, Marco; McGue, Matt; Metspalu, Andres; Mielck, Andreas; Miller, Michael B.; Montgomery, Grant W.; Mukherjee, Sutapa; Nyholt, Dale R.; Oostra, Ben A.; Palmer, Lyle J.; Palotie, Aarno; Penninx, Brenda; Perola, Markus; Peyser, Patricia A.; Preisig, Martin; Räikkönen, Katri; Raitakari, Olli T.; Realo, Anu; Ring, Susan M.; Ripatti, Samuli; Rivadeneira, Fernando; Rudan, Igor; Rustichini, Aldo; Salomaa, Veikko; Sarin, Antti-Pekka; Schlessinger, David; Scott, Rodney J.; Snieder, Harold; Pourcain, Beate St; Starr, John M.; Sul, Jae Hoon; Surakka, Ida; Svento, Rauli; Teumer, Alexander; Tiemeier, Henning; Rooij, Frank JAan; Van Wagoner, David R.; Vartiainen, Erkki; Viikari, Jorma; Vollenweider, Peter; Vonk, Judith M.; Waeber, Gérard; Weir, David R.; Wichmann, H.-Erich; Widen, Elisabeth; Willemsen, Gonneke; Wilson, James F.; Wright, Alan F.; Conley, Dalton; Davey-Smith, George; Franke, Lude; Groenen, Patrick J. F.; Hofman, Albert; Johannesson, Magnus; Kardia, Sharon L.R.; Krueger, Robert F.; Laibson, David; Martin, Nicholas G.; Meyer, Michelle N.; Posthuma, Danielle; Thurik, A. Roy; Timpson, Nicholas J.; Uitterlinden, André G.; van Duijn, Cornelia M.; Visscher, Peter M.; Benjamin, Daniel J.; Cesarini, David; Koellinger, Philipp D.

2013-01-01

A genome-wide association study of educational attainment was conducted in a discovery sample of 101,069 individuals and a replication sample of 25,490. Three independent SNPs are genome-wide significant (rs9320913, rs11584700, rs4851266), and all three replicate. Estimated effects sizes are small (R2 ≈ 0.02%), approximately 1 month of schooling per allele. A linear polygenic score from all measured SNPs accounts for ≈ 2% of the variance in both educational attainment and cognitive function. Genes in the region of the loci have previously been associated with health, cognitive, and central nervous system phenotypes, and bioinformatics analyses suggest the involvement of the anterior caudate nucleus. These findings provide promising candidate SNPs for follow-up work, and our effect size estimates can anchor power analyses in social-science genetics. PMID:23722424

DNA-PK/Ku complex binds to latency-associated nuclear antigen and negatively regulates Kaposi's sarcoma-associated herpesvirus latent replication

International Nuclear Information System (INIS)

Cha, Seho; Lim, Chunghun; Lee, Jae Young; Song, Yoon-Jae; Park, Junsoo; Choe, Joonho; Seo, Taegun

2010-01-01

During latent infection, latency-associated nuclear antigen (LANA) of Kaposi's sarcoma-associated herpesvirus (KSHV) plays important roles in episomal persistence and replication. Several host factors are associated with KSHV latent replication. Here, we show that the catalytic subunit of DNA protein kinase (DNA-PKcs), Ku70, and Ku86 bind the N-terminal region of LANA. LANA was phosphorylated by DNA-PK and overexpression of Ku70, but not Ku86, impaired transient replication. The efficiency of transient replication was significantly increased in the HCT116 (Ku86 +/-) cell line, compared to the HCT116 (Ku86 +/+) cell line, suggesting that the DNA-PK/Ku complex negatively regulates KSHV latent replication.

Born to Lead? A Twin Design and Genetic Association Study of Leadership Role Occupancy*

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De Neve, Jan-Emmanuel; Mikhaylov, Slava; Dawes, Christopher T.; Christakis, Nicholas A.; Fowler, James H.

2013-01-01

We address leadership emergence and the possibility that there is a partially innate predisposition to occupy a leadership role. Employing twin design methods on data from the National Longitudinal Study of Adolescent Health, we estimate the heritability of leadership role occupancy at 24%. Twin studies do not point to specific genes or neurological processes that might be involved. We therefore also conduct association analysis on the available genetic markers. The results show that leadership role occupancy is associated with rs4950, a single nucleotide polymorphism (SNP) residing on a neuronal acetylcholine receptor gene (CHRNB3). We replicate this family-based genetic association result on an independent sample in the Framingham Heart Study. This is the first study to identify a specific genotype associated with the tendency to occupy a leadership position. The results suggest that what determines whether an individual occupies a leadership position is the complex product of genetic and environmental influences; with a particular role for rs4950. PMID:23459689

Common variant of ALPK1 is not associated with gout: a replication study.

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Chiba, Toshinori; Matsuo, Hirotaka; Sakiyama, Masayuki; Nakayama, Akiyoshi; Shimizu, Seiko; Wakai, Kenji; Suma, Shino; Nakashima, Hiroshi; Sakurai, Yutaka; Shimizu, Toru; Ichida, Kimiyoshi; Shinomiya, Nariyoshi

2015-01-01

Gout is one of the most kinds of common inflammatory arthritis as a consequence of hyperuricemia. Alpha-protein kinase 1 (ALPK1) gene locates in a gout-susceptibility locus on chromosome 4q21-31, and encodes ALPK1 protein which plays a pivotal role in the phosphorylation of myosin 1. In the previous genetic study of Taiwanese populations, 3 single nucleotide polymorphisms (SNPs), rs11726117, rs231247 and rs231253, in ALPK1 gene were reported to have a significant association with gout. However, no replication study has been performed to confirm this association. Therefore, we first conducted a replication study with clinically defined gout patients in a different population. Linkage disequilibrium (LD) analyzes of the 3 SNPs in ALPK1 revealed that these SNPs are in strong LD in a Japanese population. Among the 3 SNPs of ALPK1, rs11726117 (M861T) is the only missense SNP. Therefore, rs11726117 was genotyped in a Japanese population of 903 clinically defined gout cases and 1,302 controls, and was evaluated for a possible association with gout. The minor allele frequencies of rs11726117 were 0.26 and 0.25 in the case and control groups, respectively. The association analysis has not detected a significant association between rs11726117 and gout susceptibility in a Japanese population (p = 0.44). Because ABCG2, a major causative gene for gout, also locates in the gout-susceptibility locus on chromosome 4q, these findings suggest that among genes in a gout-susceptibility locus, not ALPK1 but ABCG2 could be important as a gout-susceptible gene.

Replication and Characterization of Association between ABO SNPs and Red Blood Cell Traits by Meta-Analysis in Europeans.

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Stela McLachlan

Full Text Available Red blood cell (RBC traits are routinely measured in clinical practice as important markers of health. Deviations from the physiological ranges are usually a sign of disease, although variation between healthy individuals also occurs, at least partly due to genetic factors. Recent large scale genetic studies identified loci associated with one or more of these traits; further characterization of known loci and identification of new loci is necessary to better understand their role in health and disease and to identify potential molecular mechanisms. We performed meta-analysis of Metabochip association results for six RBC traits-hemoglobin concentration (Hb, hematocrit (Hct, mean corpuscular hemoglobin (MCH, mean corpuscular hemoglobin concentration (MCHC, mean corpuscular volume (MCV and red blood cell count (RCC-in 11 093 Europeans from seven studies of the UCL-LSHTM-Edinburgh-Bristol (UCLEB Consortium. We identified 394 non-overlapping SNPs in five loci at genome-wide significance: 6p22.1-6p21.33 (with HFE among others, 6q23.2 (with HBS1L among others, 6q23.3 (contains no genes, 9q34.3 (only ABO gene and 22q13.1 (with TMPRSS6 among others, replicating previous findings of association with RBC traits at these loci and extending them by imputation to 1000 Genomes. We further characterized associations between ABO SNPs and three traits: hemoglobin, hematocrit and red blood cell count, replicating them in an independent cohort. Conditional analyses indicated the independent association of each of these traits with ABO SNPs and a role for blood group O in mediating the association. The 15 most significant RBC-associated ABO SNPs were also associated with five cardiometabolic traits, with discordance in the direction of effect between groups of traits, suggesting that ABO may act through more than one mechanism to influence cardiometabolic risk.

DNA replication stress and cancer chemotherapy.

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Kitao, Hiroyuki; Iimori, Makoto; Kataoka, Yuki; Wakasa, Takeshi; Tokunaga, Eriko; Saeki, Hiroshi; Oki, Eiji; Maehara, Yoshihiko

2018-02-01

DNA replication is one of the fundamental biological processes in which dysregulation can cause genome instability. This instability is one of the hallmarks of cancer and confers genetic diversity during tumorigenesis. Numerous experimental and clinical studies have indicated that most tumors have experienced and overcome the stresses caused by the perturbation of DNA replication, which is also referred to as DNA replication stress (DRS). When we consider therapeutic approaches for tumors, it is important to exploit the differences in DRS between tumor and normal cells. In this review, we introduce the current understanding of DRS in tumors and discuss the underlying mechanism of cancer therapy from the aspect of DRS. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Riverscape genetics identifies replicated ecological divergence across an Amazonian ecotone.

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Cooke, Georgina M; Landguth, Erin L; Beheregaray, Luciano B

2014-07-01

Ecological speciation involves the evolution of reproductive isolation and niche divergence in the absence of a physical barrier to gene flow. The process is one of the most controversial topics of the speciation debate, particularly in tropical regions. Here, we investigate ecologically based divergence across an Amazonian ecotone in the electric fish, Steatogenys elegans. We combine phylogenetics, genome scans, and population genetics with a recently developed individual-based evolutionary landscape genetics approach that incorporates selection. This framework is used to assess the relative contributions of geography and divergent natural selection between environments as biodiversity drivers. We report on two closely related and sympatric lineages that exemplify how divergent selection across a major Amazonian aquatic ecotone (i.e., between rivers with markedly different hydrochemical properties) may result in replicated ecologically mediated speciation. The results link selection across an ecological gradient with reproductive isolation and we propose that assortative mating based on water color may be driving the divergence. Divergence resulting from ecologically driven selection highlights the importance of considering environmental heterogeneity in studies of speciation in tropical regions. Furthermore, we show that framing ecological speciation in a spatially explicit evolutionary landscape genetics framework provides an important first step in exploring a wide range of the potential effects of spatial dependence in natural selection. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

A genome-wide association study of bipolar disorder with comorbid eating disorder replicates the SOX2-OT region.

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Liu, Xiaohua; Kelsoe, John R; Greenwood, Tiffany A

2016-01-01

Bipolar disorder is a heterogeneous mood disorder associated with several important clinical comorbidities, such as eating disorders. This clinical heterogeneity complicates the identification of genetic variants contributing to bipolar susceptibility. Here we investigate comorbidity of eating disorders as a subphenotype of bipolar disorder to identify genetic variation that is common and unique to both disorders. We performed a genome-wide association analysis contrasting 184 bipolar subjects with eating disorder comorbidity against both 1370 controls and 2006 subjects with bipolar disorder only from the Bipolar Genome Study (BiGS). The most significant genome-wide finding was observed bipolar with comorbid eating disorder vs. controls within SOX2-OT (p=8.9×10(-8) for rs4854912) with a secondary peak in the adjacent FXR1 gene (p=1.2×10(-6) for rs1805576) on chromosome 3q26.33. This region was also the most prominent finding in the case-only analysis (p=3.5×10(-7) and 4.3×10(-6), respectively). Several regions of interest containing genes involved in neurodevelopment and neuroprotection processes were also identified. While our primary finding did not quite reach genome-wide significance, likely due to the relatively limited sample size, these results can be viewed as a replication of a recent study of eating disorders in a large cohort. These findings replicate the prior association of SOX2-OT with eating disorders and broadly support the involvement of neurodevelopmental/neuroprotective mechanisms in the pathophysiology of both disorders. They further suggest that different clinical manifestations of bipolar disorder may reflect differential genetic contributions and argue for the utility of clinical subphenotypes in identifying additional molecular pathways leading to illness. Copyright © 2015 Elsevier B.V. All rights reserved.

A Novel Rrm3 Function in Restricting DNA Replication via an Orc5-Binding Domain Is Genetically Separable from Rrm3 Function as an ATPase/Helicase in Facilitating Fork Progression

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Syed, Salahuddin; Desler, Claus; Rasmussen, Lene J.; Schmidt, Kristina H.

2016-01-01

In response to replication stress cells activate the intra-S checkpoint, induce DNA repair pathways, increase nucleotide levels, and inhibit origin firing. Here, we report that Rrm3 associates with a subset of replication origins and controls DNA synthesis during replication stress. The N-terminal domain required for control of DNA synthesis maps to residues 186–212 that are also critical for binding Orc5 of the origin recognition complex. Deletion of this domain is lethal to cells lacking the replication checkpoint mediator Mrc1 and leads to mutations upon exposure to the replication stressor hydroxyurea. This novel Rrm3 function is independent of its established role as an ATPase/helicase in facilitating replication fork progression through polymerase blocking obstacles. Using quantitative mass spectrometry and genetic analyses, we find that the homologous recombination factor Rdh54 and Rad5-dependent error-free DNA damage bypass act as independent mechanisms on DNA lesions that arise when Rrm3 catalytic activity is disrupted whereas these mechanisms are dispensable for DNA damage tolerance when the replication function is disrupted, indicating that the DNA lesions generated by the loss of each Rrm3 function are distinct. Although both lesion types activate the DNA-damage checkpoint, we find that the resultant increase in nucleotide levels is not sufficient for continued DNA synthesis under replication stress. Together, our findings suggest a role of Rrm3, via its Orc5-binding domain, in restricting DNA synthesis that is genetically and physically separable from its established catalytic role in facilitating fork progression through replication blocks. PMID:27923055

A Novel Rrm3 Function in Restricting DNA Replication via an Orc5-Binding Domain Is Genetically Separable from Rrm3 Function as an ATPase/Helicase in Facilitating Fork Progression.

Science.gov (United States)

Syed, Salahuddin; Desler, Claus; Rasmussen, Lene J; Schmidt, Kristina H

2016-12-01

In response to replication stress cells activate the intra-S checkpoint, induce DNA repair pathways, increase nucleotide levels, and inhibit origin firing. Here, we report that Rrm3 associates with a subset of replication origins and controls DNA synthesis during replication stress. The N-terminal domain required for control of DNA synthesis maps to residues 186-212 that are also critical for binding Orc5 of the origin recognition complex. Deletion of this domain is lethal to cells lacking the replication checkpoint mediator Mrc1 and leads to mutations upon exposure to the replication stressor hydroxyurea. This novel Rrm3 function is independent of its established role as an ATPase/helicase in facilitating replication fork progression through polymerase blocking obstacles. Using quantitative mass spectrometry and genetic analyses, we find that the homologous recombination factor Rdh54 and Rad5-dependent error-free DNA damage bypass act as independent mechanisms on DNA lesions that arise when Rrm3 catalytic activity is disrupted whereas these mechanisms are dispensable for DNA damage tolerance when the replication function is disrupted, indicating that the DNA lesions generated by the loss of each Rrm3 function are distinct. Although both lesion types activate the DNA-damage checkpoint, we find that the resultant increase in nucleotide levels is not sufficient for continued DNA synthesis under replication stress. Together, our findings suggest a role of Rrm3, via its Orc5-binding domain, in restricting DNA synthesis that is genetically and physically separable from its established catalytic role in facilitating fork progression through replication blocks.

Replicative senescence of T cells: does the Hayflick Limit lead to immune exhaustion?

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Effros, R B; Pawelec, G

1997-09-01

Extensive in vitro research on fibroblasts has defined numerous genetic and phenotypic changes associated with replicative senescence. Identification of T-cell replicative senescence as a feature of human immunodeficiency virus (HIV) disease and ageing suggests this phenomenon merits more careful consideration by immunologists, especially with regard to chronic infection, memory and adoptive immunotherapy.

Viral hijacking of a replicative helicase loader and its implications for helicase loading control and phage replication

Energy Technology Data Exchange (ETDEWEB)

Hood, Iris V.; Berger, James M.

2016-05-31

Replisome assembly requires the loading of replicative hexameric helicases onto origins by AAA+ ATPases. How loader activity is appropriately controlled remains unclear. Here, we use structural and biochemical analyses to establish how an antimicrobial phage protein interferes with the function of theStaphylococcus aureusreplicative helicase loader, DnaI. The viral protein binds to the loader’s AAA+ ATPase domain, allowing binding of the host replicative helicase but impeding loader self-assembly and ATPase activity. Close inspection of the complex highlights an unexpected locus for the binding of an interdomain linker element in DnaI/DnaC-family proteins. We find that the inhibitor protein is genetically coupled to a phage-encoded homolog of the bacterial helicase loader, which we show binds to the host helicase but not to the inhibitor itself. These findings establish a new approach by which viruses can hijack host replication processes and explain how loader activity is internally regulated to prevent aberrant auto-association.

Using CSF biomarkers to replicate genetic associations in Alzheimer's disease

NARCIS (Netherlands)

Schott, Jonathan M.; Abdi, Hervé; Abdul Hadi, Normi; Abdulkadir, Ahmed; Abdullah, Afnizanfaizal; Achuthan, Anusha; Adluru, Nagesh; Aggarwal, Namita; Aghajanian, Jania; Agyemang, Alex; Ahdidan, Jamila; Ahmad, Duaa; Ahmed, Fayeza; Ahmed, Shiek; Ahmed, Fareed; Akbarifar, Roshanak; Akhondi-Asl, Alireza; Aksu, Yaman; Alcauter, Sarael; Alexander, Daniel; Alin, Aylin; Alshuft, Hamza; Alvarez-Linera, Juan; Amin-Mansour, Ali; Anderson, Jeff; Anderson, Dallas; Andorn, Anne; Andrews, K. Abigail; Ang, Amma; Angersbach, Steve; Ansarian, Reza; Abhishek, Appaji M.; Appannah, Arti; Arfanakis, Konstantinos; Arif, Muhammad; Armentrout, Steven; Arrighi, Michael; Arumughababu, S. Vethanayaki; Arunagiri, Vidhya; Ashe-McNalley, Cody; Ashford, Wes; Le Page, Aurelie; Avants, Brian; Aviv, Richard; Avula, Ramesh; Ayache, Nicholas; Ayan-Oshodi, Mosun; Ayhan, Murat; Richard, Edo; Schmand, Ben

2012-01-01

Defining cases and controls on the basis of biomarkers rather than clinical diagnosis may reduce sample sizes required for genetic studies. The aim of this study was to assess whether characterizing case/control status on the basis of cerebrospinal fluid (CSF) profile would increase power to

Genetic variants associated with severe retinopathy of prematurity in extremely low birth weight infants.

Science.gov (United States)

Hartnett, M Elizabeth; Morrison, Margaux A; Smith, Silvia; Yanovitch, Tammy L; Young, Terri L; Colaizy, Tarah; Momany, Allison; Dagle, John; Carlo, Waldemar A; Clark, Erin A S; Page, Grier; Murray, Jeff; DeAngelis, Margaret M; Cotten, C Michael

2014-08-12

To determine genetic variants associated with severe retinopathy of prematurity (ROP) in a candidate gene cohort study of US preterm infants. Preterm infants in the discovery cohort were enrolled through the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network, and those in the replication cohort were from the University of Iowa. All infants were phenotyped for ROP severity. Because of differences in the durations of enrollment between cohorts, severe ROP was defined as threshold disease in the discovery cohort and as threshold disease or type 1 ROP in the replication cohort. Whole genome amplified DNA from stored blood spot samples from the Neonatal Research Network biorepository was genotyped using an Illumina GoldenGate platform for candidate gene single nucleotide polymorphisms (SNPs) involving angiogenic, developmental, inflammatory, and oxidative pathways. Three analyses were performed to determine significant epidemiologic variables and SNPs associated with levels of ROP severity. Analyses controlled for multiple comparisons, ancestral eigenvalues, family relatedness, and significant epidemiologic variables. Single nucleotide polymorphisms significantly associated with ROP severity from the discovery cohort were analyzed in the replication cohort and in meta-analysis. Eight hundred seventeen infants in the discovery cohort and 543 in the replication cohort were analyzed. Severe ROP occurred in 126 infants in the discovery and in 14 in the replication cohort. In both cohorts, ventilation days and seizure occurrence were associated with severe ROP. After controlling for significant factors and multiple comparisons, two intronic SNPs in the gene BDNF (rs7934165 and rs2049046, P large candidate gene study of infants with threshold ROP. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

DNA replication and cancer

DEFF Research Database (Denmark)

Boyer, Anne-Sophie; Walter, David; Sørensen, Claus Storgaard

2016-01-01

A dividing cell has to duplicate its DNA precisely once during the cell cycle to preserve genome integrity avoiding the accumulation of genetic aberrations that promote diseases such as cancer. A large number of endogenous impacts can challenge DNA replication and cells harbor a battery of pathways...... causing DNA replication stress and genome instability. Further, we describe cellular and systemic responses to these insults with a focus on DNA replication restart pathways. Finally, we discuss the therapeutic potential of exploiting intrinsic replicative stress in cancer cells for targeted therapy....

Identification of rep-associated factors in herpes simplex virus type 1-induced adeno-associated virus type 2 replication compartments.

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Nicolas, Armel; Alazard-Dany, Nathalie; Biollay, Coline; Arata, Loredana; Jolinon, Nelly; Kuhn, Lauriane; Ferro, Myriam; Weller, Sandra K; Epstein, Alberto L; Salvetti, Anna; Greco, Anna

2010-09-01

Adeno-associated virus (AAV) is a human parvovirus that replicates only in cells coinfected with a helper virus, such as adenovirus or herpes simplex virus type 1 (HSV-1). We previously showed that nine HSV-1 factors are able to support AAV rep gene expression and genome replication. To elucidate the strategy of AAV replication in the presence of HSV-1, we undertook a proteomic analysis of cellular and HSV-1 factors associated with Rep proteins and thus potentially recruited within AAV replication compartments (AAV RCs). This study resulted in the identification of approximately 60 cellular proteins, among which factors involved in DNA and RNA metabolism represented the largest functional categories. Validation analyses indicated that the cellular DNA replication enzymes RPA, RFC, and PCNA were recruited within HSV-1-induced AAV RCs. Polymerase delta was not identified but subsequently was shown to colocalize with Rep within AAV RCs even in the presence of the HSV-1 polymerase complex. In addition, we found that AAV replication is associated with the recruitment of components of the Mre11/Rad50/Nbs1 complex, Ku70 and -86, and the mismatch repair proteins MSH2, -3, and -6. Finally, several HSV-1 factors were also found to be associated with Rep, including UL12. We demonstrated for the first time that this protein plays a role during AAV replication by enhancing the resolution of AAV replicative forms and AAV particle production. Altogether, these analyses provide the basis to understand how AAV adapts its replication strategy to the nuclear environment induced by the helper virus.

Genome-wide assessment for genetic variants associated with ventricular dysfunction after primary coronary artery bypass graft surgery.

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Amanda A Fox

Full Text Available BACKGROUND: Postoperative ventricular dysfunction (VnD occurs in 9-20% of coronary artery bypass graft (CABG surgical patients and is associated with increased postoperative morbidity and mortality. Understanding genetic causes of postoperative VnD should enhance patient risk stratification and improve treatment and prevention strategies. We aimed to determine if genetic variants associate with occurrence of in-hospital VnD after CABG surgery. METHODS: A genome-wide association study identified single nucleotide polymorphisms (SNPs associated with postoperative VnD in male subjects of European ancestry undergoing isolated primary CABG surgery with cardiopulmonary bypass. VnD was defined as the need for ≥2 inotropes or mechanical ventricular support after CABG surgery. Validated SNPs were assessed further in two replication CABG cohorts and meta-analysis was performed. RESULTS: Over 100 SNPs were associated with VnD (P2.1 of developing in-hospital VnD after CABG surgery. However, three genetic loci identified by meta-analysis were more modestly associated with development of postoperative VnD. Studies of larger cohorts to assess these loci as well as to define other genetic mechanisms and related biology that link genetic variants to postoperative ventricular dysfunction are warranted.

A large replication study and meta-analysis in European samples provides further support for association of AHI1 markers with schizophrenia

DEFF Research Database (Denmark)

Ingason, Andrés; Giegling, Ina; Cichon, Sven

2010-01-01

The Abelson helper integration site 1 (AHI1) gene locus on chromosome 6q23 is among a group of candidate loci for schizophrenia susceptibility that were initially identified by linkage followed by linkage disequilibrium mapping, and subsequent replication of the association in an independent sample....... Here, we present results of a replication study of AHI1 locus markers, previously implicated in schizophrenia, in a large European sample (in total 3907 affected and 7429 controls). Furthermore, we perform a meta-analysis of the implicated markers in 4496 affected and 18,920 controls. Both...... as the neighbouring phosphodiesterase 7B (PDE7B)-may be considered candidates for involvement in the genetic aetiology of schizophrenia....

Genetic variation at the Th2 immune gene IL13 is associated with IgE-mediated paediatric food allergy.

Science.gov (United States)

Ashley, S E; Tan, H-T T; Peters, R; Allen, K J; Vuillermin, P; Dharmage, S C; Tang, M L K; Koplin, J; Lowe, A; Ponsonby, A-L; Molloy, J; Matheson, M C; Saffery, R; Ellis, J A; Martino, D

2017-08-01

Food allergies pose a considerable world-wide public health burden with incidence as high as one in ten in 12-month-old infants. Few food allergy genetic risk variants have yet been identified. The Th2 immune gene IL13 is a highly plausible genetic candidate as it is central to the initiation of IgE class switching in B cells. Here, we sought to investigate whether genetic polymorphisms at IL13 are associated with the development of challenge-proven IgE-mediated food allergy. We genotyped nine IL13 "tag" single nucleotide polymorphisms (tag SNPs) in 367 challenge-proven food allergic cases, 199 food-sensitized tolerant cases and 156 non-food allergic controls from the HealthNuts study. 12-month-old infants were phenotyped using open oral food challenges. SNPs were tested using Cochran-Mantel-Haenszel test adjusted for ancestry strata. A replication study was conducted in an independent, co-located sample of four paediatric cohorts consisting of 203 food allergic cases and 330 non-food allergic controls. Replication sample phenotypes were defined by clinical history of reactivity, 95% PPV or challenge, and IL13 genotyping was performed. IL13 rs1295686 was associated with challenge-proven food allergy in the discovery sample (P=.003; OR=1.75; CI=1.20-2.53). This association was also detected in the replication sample (P=.03, OR=1.37, CI=1.03-1.82) and further supported by a meta-analysis (P=.0006, OR=1.50). However, we cannot rule out an association with food sensitization. Carriage of the rs1295686 variant A allele was also associated with elevated total plasma IgE. We show for the first time, in two independent cohorts, that IL13 polymorphism rs1295686 (in complete linkage disequilibrium with functional variant rs20541) is associated with challenge-proven food allergy. © 2017 John Wiley & Sons Ltd.

Genetic loci associated with chronic obstructive pulmonary disease overlap with loci for lung function and pulmonary fibrosis

NARCIS (Netherlands)

Hobbs, Brian D; de Jong, Kim; Lamontagne, Maxime; Bossé, Yohan; Shrine, Nick; Artigas, María Soler; Wain, Louise V; Hall, Ian P; Jackson, Victoria E; Wyss, Annah B; London, Stephanie J; North, Kari E; Franceschini, Nora; Strachan, David P; Beaty, Terri H; Hokanson, John E; Crapo, James D; Castaldi, Peter J; Chase, Robert P; Bartz, Traci M; Heckbert, Susan R; Psaty, Bruce M; Gharib, Sina A; Zanen, Pieter; Lammers, Jan W; Oudkerk, Matthijs; Groen, H J; Locantore, Nicholas; Tal-Singer, Ruth; Rennard, Stephen I; Vestbo, Jørgen; Timens, Wim; Paré, Peter D; Latourelle, Jeanne C; Dupuis, Josée; O'Connor, George T; Wilk, Jemma B; Kim, Woo Jin; Lee, Mi Kyeong; Oh, Yeon-Mok; Vonk, Judith M; de Koning, Harry J; Leng, Shuguang; Belinsky, Steven A; Tesfaigzi, Yohannes; Manichaikul, Ani; Wang, Xin-Qun; Rich, Stephen S; Barr, R Graham; Sparrow, David; Litonjua, Augusto A; Bakke, Per; Gulsvik, Amund; Lahousse, Lies; Brusselle, Guy G; Stricker, Bruno H; Uitterlinden, André G; Ampleford, Elizabeth J; Bleecker, Eugene R; Woodruff, Prescott G; Meyers, Deborah A; Qiao, Dandi; Lomas, David A; Yim, Jae-Joon; Kim, Deog Kyeom; Hawrylkiewicz, Iwona; Sliwinski, Pawel; Hardin, Megan; Fingerlin, Tasha E; Schwartz, David A; Postma, Dirkje S; MacNee, William; Tobin, Martin D; Silverman, Edwin K; Boezen, H Marike; Cho, Michael H

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality worldwide. We performed a genetic association study in 15,256 cases and 47,936 controls, with replication of select top results (P < 5 × 10(-6)) in 9,498 cases and 9,748 controls. In the combined meta-analysis, we

CD40: Novel Association with Crohn's Disease and Replication in Multiple Sclerosis Susceptibility

Science.gov (United States)

Alcina, Antonio; Teruel, María; Díaz-Gallo, Lina M.; Gómez-García, María; López-Nevot, Miguel A.; Rodrigo, Luis; Nieto, Antonio; Cardeña, Carlos; Alcain, Guillermo; Díaz-Rubio, Manuel; de la Concha, Emilio G.; Fernandez, Oscar; Arroyo, Rafael

2010-01-01

Background A functional polymorphism located at −1 from the start codon of the CD40 gene, rs1883832, was previously reported to disrupt a Kozak sequence essential for translation. It has been consistently associated with Graves' disease risk in populations of different ethnicity and genetic proxies of this variant evaluated in genome-wide association studies have shown evidence of an effect in rheumatoid arthritis and multiple sclerosis (MS) susceptibility. However, the protective allele associated with Graves' disease or rheumatoid arthritis has shown a risk role in MS, an effect that we aimed to replicate in the present work. We hypothesized that this functional polymorphism might also show an association with other complex autoimmune condition such as inflammatory bowel disease, given the CD40 overexpression previously observed in Crohn's disease (CD) lesions. Methodology Genotyping of rs1883832C>T was performed in 1564 MS, 1102 CD and 969 ulcerative colitis (UC) Spanish patients and in 2948 ethnically matched controls by TaqMan chemistry. Principal Findings The observed effect of the minor allele rs1883832T was replicated in our independent Spanish MS cohort [p = 0.025; OR (95% CI) = 1.12 (1.01–1.23)]. The frequency of the minor allele was also significantly higher in CD patients than in controls [p = 0.002; OR (95% CI) = 1.19 (1.06–1.33)]. This increased predisposition was not detected in UC patients [p = 0.5; OR (95% CI) = 1.04 (0.93–1.17)]. Conclusion The impact of CD40 rs1883832 on MS and CD risk points to a common signaling shared by these autoimmune conditions. PMID:20634952

Genetic Moderation of Stability in Attachment Security from Early Childhood to Age 18 Years: A Replication Study

Science.gov (United States)

Raby, K. Lee; Roisman, Glenn I.; Booth-LaForce, Cathryn

2015-01-01

A longstanding question for attachment theory and research is whether genetically based characteristics of the child influence the development of attachment security and its stability over time. This study attempted to replicate and extend recent findings indicating that the developmental stability of attachment security is moderated by oxytocin…

GWA study data mining and independent replication identify cardiomyopathy-associated 5 (CMYA5) as a risk gene for schizophrenia

DEFF Research Database (Denmark)

Chen, X; Lee, G; Maher, B S

2011-01-01

We conducted data-mining analyses using the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) and molecular genetics of schizophrenia genome-wide association study supported by the genetic association information network (MGS-GAIN) schizophrenia data sets and performed...... bioinformatic prioritization for all the markers with P-values ¿0.05 in both data sets. In this process, we found that in the CMYA5 gene, there were two non-synonymous markers, rs3828611 and rs10043986, showing nominal significance in both the CATIE and MGS-GAIN samples. In a combined analysis of both the CATIE...... in our Irish samples and was dropped out without further investigation. The other two markers were verified in 23 other independent data sets. In a meta-analysis of all 23 replication samples (family samples, 912 families with 4160 subjects; case-control samples, 11¿380 cases and 15¿021 controls), we...

STrengthening the REporting of Genetic Association Studies (STREGA – An Extension of the STROBE Statement

Directory of Open Access Journals (Sweden)

Julian Little

2009-09-01

Full Text Available Making sense of rapidly evolving evidence on genetic associations is crucial to making genuine advances in human genomics and the eventual integration of this information in the practice of medicine and public health. Assessment of the strengths and weaknesses of this evidence, and hence the ability to synthesize it, has been limited by inadequate reporting of results. The STrengthening the REporting of Genetic Association studies (STREGA initiative builds on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE Statement and provides additions to 12 of the 22 items on the STROBE checklist. The additions concern population stratification, genotyping errors, modelling haplotype variation, Hardy-Weinberg equilibrium, replication, selection of participants, rationale for choice of genes and variants, treatment effects in studying quantitative traits, statistical methods, relatedness, reporting of descriptive and outcome data, and the volume of data issues that are important to consider in genetic association studies. The STREGA recommendations do not prescribe or dictate how a genetic association study should be designed but seek to enhance the transparency of its reporting, regardless of choices made during design, conduct, or analysis.

DNA-PK/Ku complex binds to latency-associated nuclear antigen and negatively regulates Kaposi's sarcoma-associated herpesvirus latent replication

Energy Technology Data Exchange (ETDEWEB)

Cha, Seho [Department of Life Science, Dongguk Univ-Seoul, Seoul 100-715 (Korea, Republic of); Lim, Chunghun [Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Lee, Jae Young [Department of Life Science, Dongguk Univ-Seoul, Seoul 100-715 (Korea, Republic of); Song, Yoon-Jae [Department of Life Science, Kyungwon University, Seongnam-Si, Kyeonggi-Do 461-701 (Korea, Republic of); Park, Junsoo [Division of Biological Science and Technology, Yonsei University, Wonju 220-100 (Korea, Republic of); Choe, Joonho [Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Seo, Taegun, E-mail: tseo@dongguk.edu [Department of Life Science, Dongguk Univ-Seoul, Seoul 100-715 (Korea, Republic of)

2010-04-16

During latent infection, latency-associated nuclear antigen (LANA) of Kaposi's sarcoma-associated herpesvirus (KSHV) plays important roles in episomal persistence and replication. Several host factors are associated with KSHV latent replication. Here, we show that the catalytic subunit of DNA protein kinase (DNA-PKcs), Ku70, and Ku86 bind the N-terminal region of LANA. LANA was phosphorylated by DNA-PK and overexpression of Ku70, but not Ku86, impaired transient replication. The efficiency of transient replication was significantly increased in the HCT116 (Ku86 +/-) cell line, compared to the HCT116 (Ku86 +/+) cell line, suggesting that the DNA-PK/Ku complex negatively regulates KSHV latent replication.

Susceptibility loci for sporadic brain arteriovenous malformation; a replication study and meta-analysis

NARCIS (Netherlands)

Kremer, P.H.; Koeleman, B.P.C.; Rinkel, G.J.; Diekstra, F.P.; Berg, L.H. van den; Veldink, J.H.; Klijn, C.J.M.

2016-01-01

BACKGROUND: Case-control studies have reported multiple genetic loci to be associated with sporadic brain arteriovenous malformations (AVMs) but most of these have not been replicated in independent populations. The aim of this study was to find additional evidence for these reported associations

Trans-ancestry genome-wide association study identifies 12 genetic loci influencing blood pressure and implicates a role for DNA methylation

NARCIS (Netherlands)

N. Kato (Norihiro); M. Loh (Marie); F. Takeuchi (Fumihiko); N. Verweij (Niek); X. Wang (Xu); W. Zhang (Weihua); T. NKelly (Tanika); D. Saleheen; B. Lehne (Benjamin); I.M. Leach (Irene Mateo); A. Drong (Alexander); J. Abbott (James); S. Wahl (Simone); S.-T. Tan (Sian-Tsung); W.R. Scott (William R.); G. Campanella (Gianluca); M. Chadeau-Hyam (Marc); U. Afzal (Uzma); T.S. Ahluwalia (Tarunveer Singh); M.J. Bonder (Marc); P. Chen (Ping); A. Dehghan (Abbas); T.L. Edwards (Todd L.); T. Esko (Tõnu); M.J. Go (Min Jin); S.E. Harris (Sarah); J. Hartiala (Jaana); S. Kasela (Silva); A. Kasturiratne (Anuradhani); C.C. Khor; M.E. Kleber (Marcus); H. Li (Huaixing); Z.Y. Mok (Zuan Yu); M. Nakatochi (Masahiro); N.S. Sapari (Nur Sabrina); R. Saxena (Richa); A.F. Stewart (Alexandre F.); L. Stolk (Lisette); Y. Tabara (Yasuharu); A.L. Teh (Ai Ling); Y. Wu (Ying); J.-Y. Wu (Jer-Yuarn); Y. Zhang (Yi); I. Aits (Imke); A. Da Silva Couto Alves (Alexessander); S. Das (Shikta); R. Dorajoo (Rajkumar); J. CHopewell (Jemma); Y.K. Kim (Yun Kyoung); R. WKoivula (Robert); J. Luan (Jian'An); L.-P. Lyytikäinen (Leo-Pekka); Q. NNguyen (Quang); M.A. Pereira (Mark A); D. Postmus (Douwe); O. TRaitakari (Olli); M. Scannell Bryan (Molly); R.A. Scott (Robert); R. Sorice; V. Tragante (Vinicius); M. Traglia (Michela); J. White (Jon); K. Yamamoto (Ken); Y. Zhang (Yonghong); L.S. Adair (Linda); A. Ahmed (Alauddin); K. Akiyama (Koichi); R. Asif (Rasheed); T. Aung (Tin); I.E. Barroso (Inês); A. Bjonnes (Andrew); T.R. Braun (Timothy R.); H. Cai (Hui); L.-C. Chang (Li-Ching); C.-H. Chen; C-Y. Cheng (Ching-Yu); Y.-S. Chong (Yap-Seng); F.S. Collins (Francis); R. Courtney (Regina); G. Davies (Gail); G. Delgado; L.D. Do (Loi D.); P.A. Doevendans (Pieter); R.T. Gansevoort (Ron); Y. Gao; T.B. Grammer (Tanja B); N. Grarup (Niels); J. Grewal (Jagvir); D. Gu (D.); G. SWander (Gurpreet); A.L. Hartikainen; S.L. Hazen (Stanley); J. He (Jing); C.K. Heng (Chew-Kiat); E.J.A. Hixso (E. James Ames); A. Hofman (Albert); C. Hsu (Chris); W. Huang (Wei); L.L.N. Husemoen (Lise Lotte); J.-Y. Hwang (Joo-Yeon); S. Ichihara (Sahoko); M. Igase (Michiya); M. Isono (Masato); J.M. Justesen (Johanne M.); T. Katsuya (Tomohiro); M. GKibriya (Muhammad); Y.J. Kim; M. Kishimoto (Miyako); W.-P. Koh (Woon-Puay); K. Kohara (Katsuhiko); M. Kumari (Meena); K. Kwek (Kenneth); N.R. Lee (Nanette); J. Lee (Jeannette); J. Liao (Jie); W. Lieb (Wolfgang); D.C. Liewald (David C.); T. Matsubara (Tatsuaki); Y. Matsushita (Yumi); T. Meitinger (Thomas); E. Mihailov (Evelin); L. Milani (Lili); R. Mills (Rebecca); K. Mononen (Kari); M. Müller-Nurasyid (Martina); T. Nabika (Toru); E. Nakashima (Eitaro); H.K. Ng (Hong Kiat); K. Nikus (Kjell); T. Nutile; T. Ohkubo (Takayoshi); K. Ohnaka (Keizo); S. Parish (Sarah); L. Paternoster (Lavinia); H. Peng (Hao); A. Peters (Annette); S. TPham (Son); M.J. Pinidiyapathirage (Mohitha J.); M. Rahman (Mahfuzar); H. Rakugi (Hiromi); O. Rolandsson (Olov); M.A. Rozario (Michelle Ann); D. Ruggiero; C. Sala (Cinzia); R. Sarju (Ralhan); K. Shimokawa (Kazuro); H. Snieder (Harold); T. Sparsø (Thomas); W. Spiering (Wilko); J.M. Starr (John); D.J. Stott (David J.); D. OStram (Daniel); T. Sugiyama (Takao); S. Szymczak (Silke); W.H.W. Tang (W.H. Wilson); L. Tong (Lin); S. Trompet (Stella); V. Turjanmaa (Väinö); H. Ueshima (Hirotsugu); A.G. Uitterlinden (André); S. Umemura (Satoshi); M. Vaarasmaki (Marja); R.M. Dam (Rob Mvan); W.H. van Gilst (Wiek); D.J. van Veldhuisen (Dirk); J. Viikari (Jorma); M. Waldenberger (Melanie); Y. Wang (Yiqin); A. Wang (Aili); R. Wilson (Rory); T.Y. Wong (Tien Yin); Y.-B. Xiang (Yong-Bing); S. Yamaguchi (Shuhei); X. Ye (Xingwang); R. Young (Robin); T.L. Young (Terri); J.-M. Yuan (Jian-Min); X. Zhou (Xueya); F.W. Asselbergs (Folkert); M. Ciullo; R. Clarke (Robert); P. Deloukas (Panagiotis); A. Franke (Andre); W.F. Paul (W. Frank); S. Franks (Steve); Y. Friedlander (Yechiel); M.D. Gross (Myron D.); Z. Guo (Zhirong); T. Hansen (T.); M.-R. Jarvelin (Marjo-Riitta); T. Jørgensen (Torben); J.W. Jukema (Jan Wouter); M. Kähönen (Mika); H. Kajio (Hiroshi); M. Kivimaki (Mika); J.-Y. Lee (Jong-Young); T. Lehtimäki (Terho); A. Linneberg (Allan); T. Miki (Tetsuro); O. Pedersen (Oluf); N.J. Samani (Nilesh); T.I.A. Sørensen (Thorkild); R. Takayanagi (Ryoichi); D. Toniolo (Daniela); H. Ahsan (Habibul); H. Allayee (Hooman); Y.-T. Chen (Yuan-Tsong); J. Danesh (John); I.J. Deary (Ian J.); O.H. Franco (Oscar); L. Franke (Lude); B. THeijman (Bastiaan); J.D. Holbrook (Joanna D.); A.J. Isaacs (Aaron); B.-J. Kim (Bong-Jo); X. Lin (Xu); J. Liu (Jianjun); W. März (Winfried); A. Metspalu (Andres); K.L. Mohlke (Karen); K. Sangher; D. Harambir (Dharambir); X.-O. Shu (Xiao-Ou); J.B.J. van Meurs (Joyce); E.N. Vithana (Eranga); A.R. Wickremasinghe (Ananda); C. Wijmenga (Cisca); B.H.W. Wolffenbuttel (Bruce H.W.); M. Yokota (Mitsuhiro); W. Zheng (Wei); D. Zhu (Dingliang); P. Vineis (Paolo); S.A. Kyrtopoulos (Soterios A.); J.C.S. Kleinjans (Jos C.S.); M.I. McCarthy (Mark); R. Soong (Richie); C. Gieger (Christian); J. Scott (James); Y.Y. Teo (Yik Ying); J. He (Jiang); P. Elliott (Paul); E.S. Tai (Shyong); P. van der Harst (Pim); J.S. Kooner (Jaspal S.); J.C. Chambers (John)

2015-01-01

textabstractWe carried out a trans-ancestry genome-wide association and replication study of blood pressure phenotypes among up to 320,251 individuals of East Asian, European and South Asian ancestry. We find genetic variants at 12 new loci to be associated with blood pressure (P = 3.9 × 10 -11 to

Association Analysis of Genetic Variants with Type 2 Diabetes in a Mongolian Population in China

Directory of Open Access Journals (Sweden)

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.

Genetic loci associated with chronic obstructive pulmonary disease overlap with loci for lung function and pulmonary fibrosis

NARCIS (Netherlands)

Hobbs, Brian D.; de Jong, Kim; Lamontagne, Maxime; Bosse, Yohan; Shrine, Nick; Artigas, Maria Soler; Wain, Louise V.; Hall, Ian P.; Jackson, Victoria E.; Wyss, Annah B.; London, Stephanie J.; North, Kari E.; Franceschini, Nora; Strachan, David P.; Beaty, Terri H.; Hokanson, John E.; Crapo, James D.; Castaldi, Peter J.; Chase, Robert P.; Bartz, Traci M.; Heckbert, Susan R.; Psaty, Bruce M.; Gharib, Sina A.; Zanen, Pieter; Lammers, Jan W.; Oudkerk, Matthijs; Groen, H. J.; Locantore, Nicholas; Tal-Singer, Ruth; Rennard, Stephen I.; Vestbo, Jurgen; Timens, Wim; Pare, Peter D.; Latourelle, Jeanne C.; Dupuis, Josee; O'Connor, George T.; Wilk, Jemma B.; Kim, Woo Jin; Lee, Mi Kyeong; Oh, Yeon-Mok; Vonk, Judith M.; de Koning, Harry J.; Leng, Shuguang; Belinsky, Steven A.; Tesfaigzi, Yohannes; Manichaikul, Ani; Wang, Xin-Qun; Rich, Stephen S.; Postma, Dirkje S.; Boezen, H. Marike

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality worldwide(1). We performed a genetic association study in 15,256 cases and 47,936 controls, with replication of select top results (P <5 x 10(-6)) in 9,498 cases and 9,748 controls. In the combined meta-analysis, we

Nonequilibrium Phase Transitions Associated with DNA Replication

Science.gov (United States)

2011-02-11

polymerases) catalyzing the growth of a DNA primer strand (the nascent chain of nucleotides complementary to the template strand) based on the Watson ...the fraction (error rate) of monomers for which y, where y is the correct Watson - Crick complementary base of , can be obtained by ¼ X...Nonequilibrium Phase Transitions Associated with DNA Replication Hyung-June Woo* and Anders Wallqvist Biotechnology High Performance Computing

ATM is required for the repair of Topotecan-induced replication-associated double-strand breaks

International Nuclear Information System (INIS)

Köcher, Sabrina; Spies-Naumann, Anja; Kriegs, Malte; Dahm-Daphi, Jochen; Dornreiter, Irena

2013-01-01

Purpose: DNA replication is a promising target for anti-cancer therapies. Therefore, the understanding of replication-associated DNA repair mechanisms is of great interest. One key factor of DNA double-strand break (DSB) repair is the PIK kinase Ataxia-Telangiectasia Mutated (ATM) but it is still unclear whether ATM is involved in the repair of replication-associated DSBs. Here, we focused on the involvement of ATM in homology-directed repair (HDR) of indirect DSBs associated with replication. Material and methods: Experiments were performed using ATM-deficient and -proficient human cells. Replication-associated DSBs were induced with Topotecan (TPT) and compared with γ-irradiation (IR). Cell survival was measured by clonogenic assay. Overall DSB repair and HDR were evaluated by detecting residual γH2AX/53BP1 and Rad51 foci, respectively. Cell cycle distribution was analysed by flow cytometry and protein expression by Western blot. Results: ATM-deficiency leads to enhanced numbers of residual DSBs, resulting in a pronounced S/G2-block and decreased survival upon TPT-treatment. In common with IR, persisting Rad51 foci were detected following TPT-treatment. Conclusions: These results demonstrate that ATM is essentially required for the completion of HR-mediated repair of TPT-induced DSBs formed indirectly at replication forks

Genetic characterization of an adapted pandemic 2009 H1N1 influenza virus that reveals improved replication rates in human lung epithelial cells

International Nuclear Information System (INIS)

Wörmann, Xenia; Lesch, Markus; Welke, Robert-William; Okonechnikov, Konstantin; Abdurishid, Mirshat; Sieben, Christian; Geissner, Andreas; Brinkmann, Volker; Kastner, Markus; Karner, Andreas; Zhu, Rong; Hinterdorfer, Peter; Anish, Chakkumkal; Seeberger, Peter H.; Herrmann, Andreas

2016-01-01

The 2009 influenza pandemic originated from a swine-origin H1N1 virus, which, although less pathogenic than anticipated, may acquire additional virulence-associated mutations in the future. To estimate the potential risk, we sequentially passaged the isolate A/Hamburg/04/2009 in A549 human lung epithelial cells. After passage 6, we observed a 100-fold increased replication rate. High-throughput sequencing of viral gene segments identified five dominant mutations, whose contribution to the enhanced growth was analyzed by reverse genetics. The increased replication rate was pinpointed to two mutations within the hemagglutinin (HA) gene segment (HA_1 D130E, HA_2 I91L), near the receptor binding site and the stem domain. The adapted virus also replicated more efficiently in mice in vivo. Enhanced replication rate correlated with increased fusion pH of the HA protein and a decrease in receptor affinity. Our data might be relevant for surveillance of pre-pandemic strains and development of high titer cell culture strains for vaccine production. - Highlights: • We observed a spontaneous mutation of a 2009-pandemic H1N1 influenza virus in vitro. • The adaptation led to a 100-fold rise in replication rate in human A549 cells. • Adaptation was caused by two mutations in the HA gene segment. • Adaptation correlates with increased fusion pH and decreased receptor affinity.

Genetic characterization of an adapted pandemic 2009 H1N1 influenza virus that reveals improved replication rates in human lung epithelial cells

Energy Technology Data Exchange (ETDEWEB)

Wörmann, Xenia [Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin (Germany); Lesch, Markus [Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin (Germany); Steinbeis Innovation gGmbH, Center for Systems Biomedicine, Falkensee (Germany); Welke, Robert-William [Department of Biology, Molecular Biophysics, IRI Life Sciences, Humboldt-Universität zu Berlin (Germany); Okonechnikov, Konstantin; Abdurishid, Mirshat [Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin (Germany); Sieben, Christian [Department of Biology, Molecular Biophysics, IRI Life Sciences, Humboldt-Universität zu Berlin (Germany); Geissner, Andreas [Department for Biomolecular Systems, Max Planck Institute for Colloids and Interfaces, Potsdam (Germany); Institute of Chemistry and Biochemistry, Free University, Berlin (Germany); Brinkmann, Volker [Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin (Germany); Kastner, Markus [Institute for Biophysics, Johannes Kepler University, Linz (Austria); Karner, Andreas [Center for Advanced Bioanalysis GmbH (CBL), Linz (Austria); Zhu, Rong; Hinterdorfer, Peter [Institute for Biophysics, Johannes Kepler University, Linz (Austria); Anish, Chakkumkal [Department for Biomolecular Systems, Max Planck Institute for Colloids and Interfaces, Potsdam (Germany); Seeberger, Peter H. [Department for Biomolecular Systems, Max Planck Institute for Colloids and Interfaces, Potsdam (Germany); Institute of Chemistry and Biochemistry, Free University, Berlin (Germany); Herrmann, Andreas [Department of Biology, Molecular Biophysics, IRI Life Sciences, Humboldt-Universität zu Berlin (Germany); and others

2016-05-15

The 2009 influenza pandemic originated from a swine-origin H1N1 virus, which, although less pathogenic than anticipated, may acquire additional virulence-associated mutations in the future. To estimate the potential risk, we sequentially passaged the isolate A/Hamburg/04/2009 in A549 human lung epithelial cells. After passage 6, we observed a 100-fold increased replication rate. High-throughput sequencing of viral gene segments identified five dominant mutations, whose contribution to the enhanced growth was analyzed by reverse genetics. The increased replication rate was pinpointed to two mutations within the hemagglutinin (HA) gene segment (HA{sub 1} D130E, HA{sub 2} I91L), near the receptor binding site and the stem domain. The adapted virus also replicated more efficiently in mice in vivo. Enhanced replication rate correlated with increased fusion pH of the HA protein and a decrease in receptor affinity. Our data might be relevant for surveillance of pre-pandemic strains and development of high titer cell culture strains for vaccine production. - Highlights: • We observed a spontaneous mutation of a 2009-pandemic H1N1 influenza virus in vitro. • The adaptation led to a 100-fold rise in replication rate in human A549 cells. • Adaptation was caused by two mutations in the HA gene segment. • Adaptation correlates with increased fusion pH and decreased receptor affinity.

Poor replication validity of biomedical association studies reported by newspapers.

Science.gov (United States)

Dumas-Mallet, Estelle; Smith, Andy; Boraud, Thomas; Gonon, François

2017-01-01

To investigate the replication validity of biomedical association studies covered by newspapers. We used a database of 4723 primary studies included in 306 meta-analysis articles. These studies associated a risk factor with a disease in three biomedical domains, psychiatry, neurology and four somatic diseases. They were classified into a lifestyle category (e.g. smoking) and a non-lifestyle category (e.g. genetic risk). Using the database Dow Jones Factiva, we investigated the newspaper coverage of each study. Their replication validity was assessed using a comparison with their corresponding meta-analyses. Among the 5029 articles of our database, 156 primary studies (of which 63 were lifestyle studies) and 5 meta-analysis articles were reported in 1561 newspaper articles. The percentage of covered studies and the number of newspaper articles per study strongly increased with the impact factor of the journal that published each scientific study. Newspapers almost equally covered initial (5/39 12.8%) and subsequent (58/600 9.7%) lifestyle studies. In contrast, initial non-lifestyle studies were covered more often (48/366 13.1%) than subsequent ones (45/3718 1.2%). Newspapers never covered initial studies reporting null findings and rarely reported subsequent null observations. Only 48.7% of the 156 studies reported by newspapers were confirmed by the corresponding meta-analyses. Initial non-lifestyle studies were less often confirmed (16/48) than subsequent ones (29/45) and than lifestyle studies (31/63). Psychiatric studies covered by newspapers were less often confirmed (10/38) than the neurological (26/41) or somatic (40/77) ones. This is correlated to an even larger coverage of initial studies in psychiatry. Whereas 234 newspaper articles covered the 35 initial studies that were later disconfirmed, only four press articles covered a subsequent null finding and mentioned the refutation of an initial claim. Journalists preferentially cover initial findings

Poor replication validity of biomedical association studies reported by newspapers.

Directory of Open Access Journals (Sweden)

Estelle Dumas-Mallet

Full Text Available To investigate the replication validity of biomedical association studies covered by newspapers.We used a database of 4723 primary studies included in 306 meta-analysis articles. These studies associated a risk factor with a disease in three biomedical domains, psychiatry, neurology and four somatic diseases. They were classified into a lifestyle category (e.g. smoking and a non-lifestyle category (e.g. genetic risk. Using the database Dow Jones Factiva, we investigated the newspaper coverage of each study. Their replication validity was assessed using a comparison with their corresponding meta-analyses.Among the 5029 articles of our database, 156 primary studies (of which 63 were lifestyle studies and 5 meta-analysis articles were reported in 1561 newspaper articles. The percentage of covered studies and the number of newspaper articles per study strongly increased with the impact factor of the journal that published each scientific study. Newspapers almost equally covered initial (5/39 12.8% and subsequent (58/600 9.7% lifestyle studies. In contrast, initial non-lifestyle studies were covered more often (48/366 13.1% than subsequent ones (45/3718 1.2%. Newspapers never covered initial studies reporting null findings and rarely reported subsequent null observations. Only 48.7% of the 156 studies reported by newspapers were confirmed by the corresponding meta-analyses. Initial non-lifestyle studies were less often confirmed (16/48 than subsequent ones (29/45 and than lifestyle studies (31/63. Psychiatric studies covered by newspapers were less often confirmed (10/38 than the neurological (26/41 or somatic (40/77 ones. This is correlated to an even larger coverage of initial studies in psychiatry. Whereas 234 newspaper articles covered the 35 initial studies that were later disconfirmed, only four press articles covered a subsequent null finding and mentioned the refutation of an initial claim.Journalists preferentially cover initial findings

Poor replication validity of biomedical association studies reported by newspapers

Science.gov (United States)

Smith, Andy; Boraud, Thomas; Gonon, François

2017-01-01

Objective To investigate the replication validity of biomedical association studies covered by newspapers. Methods We used a database of 4723 primary studies included in 306 meta-analysis articles. These studies associated a risk factor with a disease in three biomedical domains, psychiatry, neurology and four somatic diseases. They were classified into a lifestyle category (e.g. smoking) and a non-lifestyle category (e.g. genetic risk). Using the database Dow Jones Factiva, we investigated the newspaper coverage of each study. Their replication validity was assessed using a comparison with their corresponding meta-analyses. Results Among the 5029 articles of our database, 156 primary studies (of which 63 were lifestyle studies) and 5 meta-analysis articles were reported in 1561 newspaper articles. The percentage of covered studies and the number of newspaper articles per study strongly increased with the impact factor of the journal that published each scientific study. Newspapers almost equally covered initial (5/39 12.8%) and subsequent (58/600 9.7%) lifestyle studies. In contrast, initial non-lifestyle studies were covered more often (48/366 13.1%) than subsequent ones (45/3718 1.2%). Newspapers never covered initial studies reporting null findings and rarely reported subsequent null observations. Only 48.7% of the 156 studies reported by newspapers were confirmed by the corresponding meta-analyses. Initial non-lifestyle studies were less often confirmed (16/48) than subsequent ones (29/45) and than lifestyle studies (31/63). Psychiatric studies covered by newspapers were less often confirmed (10/38) than the neurological (26/41) or somatic (40/77) ones. This is correlated to an even larger coverage of initial studies in psychiatry. Whereas 234 newspaper articles covered the 35 initial studies that were later disconfirmed, only four press articles covered a subsequent null finding and mentioned the refutation of an initial claim. Conclusion Journalists

Trans-ancestry genome-wide association study identifies 12 genetic loci influencing blood pressure and implicates a role for DNA methylation

DEFF Research Database (Denmark)

Kato, Norihiro; Loh, Marie; Takeuchi, Fumihiko

2015-01-01

We carried out a trans-ancestry genome-wide association and replication study of blood pressure phenotypes among up to 320,251 individuals of East Asian, European and South Asian ancestry. We find genetic variants at 12 new loci to be associated with blood pressure (P = 3.9 × 10(-11) to 5.0 × 10...

Trans-ancestry genome-wide association study identifies 12 genetic loci influencing blood pressure and implicates a role for DNA methylation

NARCIS (Netherlands)

Kato, Norihiro; Loh, Marie; Takeuchi, Fumihiko; Verweij, Niek; Wang, Xu; Zhang, Weihua; Kelly, Tanika N.; Saleheen, Danish; Lehne, Benjamin; Leach, Irene Mateo; Drong, Alexander W.; Abbott, James; Wahl, Simone; Tan, Sian-Tsung; Scott, William R.; Campanella, Gianluca; Chadeau-Hyam, Marc; Afzal, Uzma; Ahluwalia, Tarunveer S.; Bonder, Marc Jan; Chen, Peng; Dehghan, Abbas; Edwards, Todd L.; Esko, Tonu; Go, Min Jin; Harris, Sarah E.; Hartiala, Jaana; Kasela, Silva; Kasturiratne, Anuradhani; Khor, Chiea-Chuen; Kleber, Marcus E.; Li, Huaixing; Mok, Zuan Yu; Nakatochi, Masahiro; Sapari, Nur Sabrina; Saxena, Richa; Stewart, Alexandre F. R.; Stolk, Lisette; Tabara, Yasuharu; Teh, Ai Ling; Wu, Ying; Wu, Jer-Yuarn; Zhang, Yi; Aits, Imke; Alves, Alexessander Da Silva Couto; Das, Shikta; Dorajoo, Rajkumar; Hopewell, Jemma C.; Kim, Yun Kyoung; Koivula, Robert W.; Luan, Jian'an; Lyytikainen, Leo-Pekka; Nguyen, Quang N.; Pereira, Mark A.; Postmus, Iris; Raitakari, Olli T.; Bryan, Molly Scannell; Scott, Robert A.; Sorice, Rossella; Tragante, Vinicius; Traglia, Michela; White, Jon; Yamamoto, Ken; Zhang, Yonghong; Adair, Linda S.; Ahmed, Alauddin; Akiyama, Koichi; Asif, Rasheed; Aung, Tin; Barroso, Ines; Bjonnes, Andrew; Braun, Timothy R.; Cai, Hui; Chang, Li-Ching; Chen, Chien-Hsiun; Cheng, Ching-Yu; Chong, Yap-Seng; Collins, Rory; Courtney, Regina; Davies, Gail; Delgado, Graciela; Do, Loi D.; Doevendans, Pieter A.; Gansevoort, Ron T.; Gao, Yu-Tang; Grammer, Tanja B.; Grarup, Niels; Grewal, Jagvir; Gu, Dongfeng; Wander, Gurpreet S.; Hartikainen, Anna-Liisa; Hazen, Stanley L.; He, Jing; Heng, Chew-Kiat; Hixson, James E.; Hofman, Albert; Hsu, Chris; Huang, Wei; Husemoen, Lise L. N.; Hwang, Joo-Yeon; Ichihara, Sahoko; Igase, Michiya; Isono, Masato; Justesen, Johanne M.; Katsuy, Tomohiro; Kibriya, Muhammad G.; Kim, Young Jin; Kishimoto, Miyako; Koh, Woon-Puay; Kohara, Katsuhiko; Kumari, Meena; Kwek, Kenneth; Lee, Nanette R.; Lee, Jeannette; Liao, Jiemin; Lieb, Wolfgang; Liewald, David C. M.; Matsubara, Tatsuaki; Matsushita, Yumi; Meitinger, Thomas; Mihailov, Evelin; Milani, Lili; Mills, Rebecca; Mononen, Nina; Mueller-Nurasyid, Martina; Nabika, Toru; Nakashima, Eitaro; Ng, Hong Kiat; Nikus, Kjell; Nutile, Teresa; Ohkubo, Takayoshi; Ohnaka, Keizo; Parish, Sarah; Paternoster, Lavinia; Peng, Hao; Peters, Annette; Pham, Son T.; Pinidiyapathirage, Mohitha J.; Rahman, Mahfuzar; Rakugi, Hiromi; Rolandsson, Olov; Rozario, Michelle Ann; Ruggiero, Daniela; Sala, Cinzia F.; Sarju, Ralhan; Shimokawa, Kazuro; Snieder, Harold; Sparso, Thomas; Spiering, Wilko; Starr, John M.; Stott, David J.; Stram, Daniel O.; Sugiyama, Takao; Szymczak, Silke; Tang, W. H. Wilson; Tong, Lin; Trompet, Stella; Turjanmaa, Vaino; Ueshima, Hirotsugu; Uitterlinden, Andre G.; Umemura, Satoshi; Vaarasmaki, Marja; van Dam, Rob M.; van Gilst, Wiek H.; van Veldhuisen, Dirk J.; Viikari, Jorma S.; Waldenberger, Melanie; Wang, Yiqin; Wang, Aili; Wilson, Rory; Wong, Tien-Yin; Xiang, Yong-Bing; Yamaguchi, Shuhei; Ye, Xingwang; Young, Robin D.; Young, Terri L.; Yuan, Jian-Min; Zhou, Xueya; Asselbergs, Folkert W.; Ciullo, Marina; Clarke, Robert; Deloukas, Panos; Franke, Andre; Franks, Paul W.; Franks, Steve; Friedlander, Yechiel; Gross, Myron D.; Guo, Zhirong; Hansen, Torben; Jarvelin, Marjo-Riitta; Jorgensen, Torben; Jukema, J. Wouter; Kahonen, Mika; Kajio, Hiroshi; Kivimaki, Mika; Lee, Jong-Young; Lehtimaki, Terho; Linneberg, Allan; Miki, Tetsuro; Pedersen, Oluf; Samani, Nilesh J.; Sorensen, Thorkild I. A.; Takayanagi, Ryoichi; Toniolo, Daniela; Ahsan, Habibul; Allayee, Hooman; Chen, Yuan-Tsong; Danesh, John; Deary, Ian J.; Franco, Oscar H.; Franke, Lude; Heijman, Bastiaan T.; Holbrook, Joanna D.; Isaacs, Aaron; Kim, Bong-Jo; Lin, Xu; Liu, Jianjun; Maerz, Winfried; Metspalu, Andres; Mohlke, Karen L.; Sanghera, Dharambir K.; Shu, Xiao-Ou; van Meurs, Joyce B. J.; Vithana, Eranga; Wickremasinghe, Ananda R.; Wijmenga, Cisca; Wolffenbuttel, Bruce H. W.; Yokota, Mitsuhiro; Zheng, Wei; Zhu, Dingliang; Vineis, Paolo; Kyrtopoulos, Soterios A.; Kleinjans, Jos C. S.; McCarthy, Mark I.; Soong, Richie; Gieger, Christian; Scott, James; Teo, Yik-Ying; He, Jiang; Elliott, Paul; Tai, E. Shyong; van der Harst, Pim; Kooner, Jaspal S.; Chambers, John C.

2015-01-01

We carried out a trans-ancestry genome-wide association and replication study of blood pressure phenotypes among up to 320,251 individuals of East Asian, European and South Asian ancestry. We find genetic variants at 12 new loci to be associated with blood pressure (P = 3.9 x 10(-11) to 5.0 x

The role of IREB2 and transforming growth factor beta-1 genetic variants in COPD: a replication case-control study

LENUS (Irish Health Repository)

Chappell, Sally L

2011-02-14

Abstract Background Genetic factors are known to contribute to COPD susceptibility and these factors are not fully understood. Conflicting results have been reported for many genetic studies of candidate genes based on their role in the disease. Genome-wide association studies in combination with expression profiling have identified a number of new candidates including IREB2. A meta-analysis has implicated transforming growth factor beta-1 (TGFbeta1) as a contributor to disease susceptibility. Methods We have examined previously reported associations in both genes in a collection of 1017 white COPD patients and 912 non-diseased smoking controls. Genotype information was obtained for seven SNPs in the IREB2 gene, and for four SNPs in the TGFbeta1 gene. Allele and genotype frequencies were compared between COPD cases and controls, and odds ratios were calculated. The analysis was adjusted for age, sex, smoking and centre, including interactions of age, sex and smoking with centre. Results Our data replicate the association of IREB2 SNPs in association with COPD for SNP rs2568494, rs2656069 and rs12593229 with respective adjusted p-values of 0.0018, 0.0039 and 0.0053. No significant associations were identified for TGFbeta1. Conclusions These studies have therefore confirmed that the IREB2 locus is a contributor to COPD susceptibility and suggests a new pathway in COPD pathogenesis invoking iron homeostasis.

Genetic susceptibility markers for a breast-colorectal cancer phenotype: Exploratory results from genome-wide association studies

Science.gov (United States)

Joon, Aron; Brewster, Abenaa M.; Chen, Wei V.; Eng, Cathy; Shete, Sanjay; Casey, Graham; Schumacher, Fredrick; Lin, Yi; Harrison, Tabitha A.; White, Emily; Ahsan, Habibul; Andrulis, Irene L.; Whittemore, Alice S.; Ko Win, Aung; Schmidt, Daniel F.; Kapuscinski, Miroslaw K.; Ochs-Balcom, Heather M.; Gallinger, Steven; Jenkins, Mark A.; Newcomb, Polly A.; Lindor, Noralane M.; Peters, Ulrike; Amos, Christopher I.; Lynch, Patrick M.

2018-01-01

Background Clustering of breast and colorectal cancer has been observed within some families and cannot be explained by chance or known high-risk mutations in major susceptibility genes. Potential shared genetic susceptibility between breast and colorectal cancer, not explained by high-penetrance genes, has been postulated. We hypothesized that yet undiscovered genetic variants predispose to a breast-colorectal cancer phenotype. Methods To identify variants associated with a breast-colorectal cancer phenotype, we analyzed genome-wide association study (GWAS) data from cases and controls that met the following criteria: cases (n = 985) were women with breast cancer who had one or more first- or second-degree relatives with colorectal cancer, men/women with colorectal cancer who had one or more first- or second-degree relatives with breast cancer, and women diagnosed with both breast and colorectal cancer. Controls (n = 1769), were unrelated, breast and colorectal cancer-free, and age- and sex- frequency-matched to cases. After imputation, 6,220,060 variants were analyzed using the discovery set and variants associated with the breast-colorectal cancer phenotype at Pcolorectal cancer phenotype in the discovery and replication data (most significant; rs7430339, Pdiscovery = 1.2E-04; rs7429100, Preplication = 2.8E-03). In meta-analysis of the discovery and replication data, the most significant association remained at rs7429100 (P = 1.84E-06). Conclusion The results of this exploratory analysis did not find clear evidence for a susceptibility locus with a pleiotropic effect on hereditary breast and colorectal cancer risk, although the suggestive association of genetic variation in the region of ROBO1, a potential tumor suppressor gene, merits further investigation. PMID:29698419

MMS exposure promotes increased MtDNA mutagenesis in the presence of replication-defective disease-associated DNA polymerase γ variants.

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Stumpf, Jeffrey D; Copeland, William C

2014-10-01

Mitochondrial DNA (mtDNA) encodes proteins essential for ATP production. Mutant variants of the mtDNA polymerase cause mutagenesis that contributes to aging, genetic diseases, and sensitivity to environmental agents. We interrogated mtDNA replication in Saccharomyces cerevisiae strains with disease-associated mutations affecting conserved regions of the mtDNA polymerase, Mip1, in the presence of the wild type Mip1. Mutant frequency arising from mtDNA base substitutions that confer erythromycin resistance and deletions between 21-nucleotide direct repeats was determined. Previously, increased mutagenesis was observed in strains encoding mutant variants that were insufficient to maintain mtDNA and that were not expected to reduce polymerase fidelity or exonuclease proofreading. Increased mutagenesis could be explained by mutant variants stalling the replication fork, thereby predisposing the template DNA to irreparable damage that is bypassed with poor fidelity. This hypothesis suggests that the exogenous base-alkylating agent, methyl methanesulfonate (MMS), would further increase mtDNA mutagenesis. Mitochondrial mutagenesis associated with MMS exposure was increased up to 30-fold in mip1 mutants containing disease-associated alterations that affect polymerase activity. Disrupting exonuclease activity of mutant variants was not associated with increased spontaneous mutagenesis compared with exonuclease-proficient alleles, suggesting that most or all of the mtDNA was replicated by wild type Mip1. A novel subset of C to G transversions was responsible for about half of the mutants arising after MMS exposure implicating error-prone bypass of methylated cytosines as the predominant mutational mechanism. Exposure to MMS does not disrupt exonuclease activity that suppresses deletions between 21-nucleotide direct repeats, suggesting the MMS-induce mutagenesis is not explained by inactivated exonuclease activity. Further, trace amounts of CdCl2 inhibit mtDNA replication but

Epigenetically-inherited centromere and neocentromere DNA replicates earliest in S-phase.

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Amnon Koren

2010-08-01

Full Text Available Eukaryotic centromeres are maintained at specific chromosomal sites over many generations. In the budding yeast Saccharomyces cerevisiae, centromeres are genetic elements defined by a DNA sequence that is both necessary and sufficient for function; whereas, in most other eukaryotes, centromeres are maintained by poorly characterized epigenetic mechanisms in which DNA has a less definitive role. Here we use the pathogenic yeast Candida albicans as a model organism to study the DNA replication properties of centromeric DNA. By determining the genome-wide replication timing program of the C. albicans genome, we discovered that each centromere is associated with a replication origin that is the first to fire on its respective chromosome. Importantly, epigenetic formation of new ectopic centromeres (neocentromeres was accompanied by shifts in replication timing, such that a neocentromere became the first to replicate and became associated with origin recognition complex (ORC components. Furthermore, changing the level of the centromere-specific histone H3 isoform led to a concomitant change in levels of ORC association with centromere regions, further supporting the idea that centromere proteins determine origin activity. Finally, analysis of centromere-associated DNA revealed a replication-dependent sequence pattern characteristic of constitutively active replication origins. This strand-biased pattern is conserved, together with centromere position, among related strains and species, in a manner independent of primary DNA sequence. Thus, inheritance of centromere position is correlated with a constitutively active origin of replication that fires at a distinct early time. We suggest a model in which the distinct timing of DNA replication serves as an epigenetic mechanism for the inheritance of centromere position.

Reduced genetic distance and high replication levels increase the RNA recombination rate of hepatitis delta virus.

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Lin, Chia-Chi; Yang, Zhi-Wei; Iang, Shan-Bei; Chao, Mei

2015-01-02

Hepatitis delta virus (HDV) replication is carried out by host RNA polymerases. Since homologous inter-genotypic RNA recombination is known to occur in HDV, possibly via a replication-dependent process, we hypothesized that the degree of sequence homology and the replication level should be related to the recombination frequency in cells co-expressing two HDV sequences. To confirm this, we separately co-transfected cells with three different pairs of HDV genomic RNAs and analyzed the obtained recombinants by RT-PCR followed by restriction fragment length polymorphism and sequencing analyses. The sequence divergence between the clones ranged from 24% to less than 0.1%, and the difference in replication levels was as high as 100-fold. As expected, significant differences were observed in the recombination frequencies, which ranged from 0.5% to 47.5%. Furthermore, varying the relative amounts of parental RNA altered the dominant recombinant species produced, suggesting that template switching occurs frequently during the synthesis of genomic HDV RNA. Taken together, these data suggest that during the host RNA polymerase-driven RNA recombination of HDV, both inter- and intra-genotypic recombination events are important in shaping the genetic diversity of HDV. Copyright © 2014 Elsevier B.V. All rights reserved.

Genetic response to metabolic fluctuations: correlation between central carbon metabolism and DNA replication in Escherichia coli

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Szalewska-Pałasz Agnieszka

2011-03-01

Full Text Available Abstract Background Until now, the direct link between central carbon metabolism and DNA replication has been demonstrated only in Bacillus. subtilis. Therefore, we asked if this is a specific phenomenon, characteristic for this bacterium and perhaps for its close relatives, or a more general biological rule. Results We found that temperature-sensitivity of mutants in particular genes coding for replication proteins could be suppressed by deletions of certain genes coding for enzymes of the central carbon metabolism. Namely, the effects of dnaA46(ts mutation could be suppressed by dysfunction of pta or ackA, effects of dnaB(ts by dysfunction of pgi or pta, effects of dnaE486(ts by dysfunction of tktB, effects of dnaG(ts by dysfunction of gpmA, pta or ackA, and effects of dnaN159(ts by dysfunction of pta or ackA. The observed suppression effects were not caused by a decrease in bacterial growth rate. Conclusions The genetic correlation exists between central carbon metabolism and DNA replication in the model Gram-negative bacterium, E. coli. This link exists at the steps of initiation and elongation of DNA replication, indicating the important global correlation between metabolic status of the cell and the events leading to cell reproduction.

Association between Maternal Fish Consumption and Gestational Weight Gain: Influence of Molecular Genetic Predisposition to Obesity.

Directory of Open Access Journals (Sweden)

Sofus C Larsen

Full Text Available Studies suggest that fish consumption can restrict weight gain. However, little is known about how fish consumption affects gestational weight gain (GWG, and whether this relationship depends on genetic makeup.To examine the association between fish consumption and GWG, and whether this relationship is dependent on molecular genetic predisposition to obesity.A nested case-cohort study based on the Danish National Birth Cohort (DNBC sampling the most obese women (n = 990 and a random sample of the remaining participants (n = 1,128. Replication of statistically significant findings was attempted in the Avon Longitudinal Study of Parents and Children (ALSPAC (n = 4,841. We included 32 body mass index (BMI associated single nucleotide polymorphisms (SNPs and 5 SNPs found associated with GWG. BMI associated SNPs were combined in a genetic risk score (GRS. Associations between consumption of fish, GRS or individual variants and GWG were analysed, and interactions between fish and the GRS or individual variants were examined.In the DNBC, each portion/week (150 g of fatty fish was associated with a higher GWG of 0.58 kg (95% CI: 0.16, 0.99, P<0.01. For total fish and lean fish, similar patterns were observed, but these associations were not statistically significant. We found no association between GRS and GWG, and no interactions between GRS and dietary fish on GWG. However, we found an interaction between the PPARG Pro12Ala variant and dietary fish. Each additional Pro12Ala G-allele was associated with a GWG of -0.83 kg (95% CI: -1.29, -0.37, P<0.01 per portion/week of dietary fish, with the same pattern for both lean and fatty fish. In ALSPAC, we were unable to replicate these findings.We found no consistent evidence of association between fish consumption and GWG, and our results indicate that the association between dietary fish and GWG has little or no dependency on GRS or individual SNPs.

Genetic Association of CD247 (CD3ζ) with SLE in a Large-Scale Multiethnic Study

OpenAIRE

Martins, Madalena; Williams, Adrienne H.; Comeau, Mary; Marion, Miranda; Ziegler, Julie T.; Freedman, Barry I.; Merrill, Joan T.; Glenn, Stuart B.; Kelly, Jennifer A.; Sivils, Kathy M.; James, Judith A.; Guthridge, Joel M.; Alarcón-Riquelme, Marta E.; Bae, Sang-Cheol; Kim, Jae-Hoon

2015-01-01

A classic T-cell phenotype in systemic lupus erythematosus (SLE) is the downregulation and replacement of the CD3ζ chain that alters T-cell receptor signaling. However, genetic associations with SLE in the human CD247 locus that encodes CD3ζ are not well established and require replication in independent cohorts. Our aim was therefore to examine, localize and validate CD247-SLE association in a large multiethnic population. We typed 44 contiguous CD247 single-nucleotide polymorphisms (SNPs) i...

Genome-wide association identifies genetic variants associated with lentiform nucleus volume in N = 1345 young and elderly subjects.

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Hibar, Derrek P; Stein, Jason L; Ryles, April B; Kohannim, Omid; Jahanshad, Neda; Medland, Sarah E; Hansell, Narelle K; McMahon, Katie L; de Zubicaray, Greig I; Montgomery, Grant W; Martin, Nicholas G; Wright, Margaret J; Saykin, Andrew J; Jack, Clifford R; Weiner, Michael W; Toga, Arthur W; Thompson, Paul M

2013-06-01

Deficits in lentiform nucleus volume and morphometry are implicated in a number of genetically influenced disorders, including Parkinson's disease, schizophrenia, and ADHD. Here we performed genome-wide searches to discover common genetic variants associated with differences in lentiform nucleus volume in human populations. We assessed structural MRI scans of the brain in two large genotyped samples: the Alzheimer's Disease Neuroimaging Initiative (ADNI; N = 706) and the Queensland Twin Imaging Study (QTIM; N = 639). Statistics of association from each cohort were combined meta-analytically using a fixed-effects model to boost power and to reduce the prevalence of false positive findings. We identified a number of associations in and around the flavin-containing monooxygenase (FMO) gene cluster. The most highly associated SNP, rs1795240, was located in the FMO3 gene; after meta-analysis, it showed genome-wide significant evidence of association with lentiform nucleus volume (P MA  = 4.79 × 10(-8)). This commonly-carried genetic variant accounted for 2.68 % and 0.84 % of the trait variability in the ADNI and QTIM samples, respectively, even though the QTIM sample was on average 50 years younger. Pathway enrichment analysis revealed significant contributions of this gene to the cytochrome P450 pathway, which is involved in metabolizing numerous therapeutic drugs for pain, seizures, mania, depression, anxiety, and psychosis. The genetic variants we identified provide replicated, genome-wide significant evidence for the FMO gene cluster's involvement in lentiform nucleus volume differences in human populations.

Web-based genome-wide association study identifies two novel loci and a substantial genetic component for Parkinson's disease.

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Chuong B Do

2011-06-01

Full Text Available Although the causes of Parkinson's disease (PD are thought to be primarily environmental, recent studies suggest that a number of genes influence susceptibility. Using targeted case recruitment and online survey instruments, we conducted the largest case-control genome-wide association study (GWAS of PD based on a single collection of individuals to date (3,426 cases and 29,624 controls. We discovered two novel, genome-wide significant associations with PD-rs6812193 near SCARB2 (p = 7.6 × 10(-10, OR = 0.84 and rs11868035 near SREBF1/RAI1 (p = 5.6 × 10(-8, OR = 0.85-both replicated in an independent cohort. We also replicated 20 previously discovered genetic associations (including LRRK2, GBA, SNCA, MAPT, GAK, and the HLA region, providing support for our novel study design. Relying on a recently proposed method based on genome-wide sharing estimates between distantly related individuals, we estimated the heritability of PD to be at least 0.27. Finally, using sparse regression techniques, we constructed predictive models that account for 6%-7% of the total variance in liability and that suggest the presence of true associations just beyond genome-wide significance, as confirmed through both internal and external cross-validation. These results indicate a substantial, but by no means total, contribution of genetics underlying susceptibility to both early-onset and late-onset PD, suggesting that, despite the novel associations discovered here and elsewhere, the majority of the genetic component for Parkinson's disease remains to be discovered.

Drosophila duplication hotspots are associated with late-replicating regions of the genome.

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Margarida Cardoso-Moreira

2011-11-01

Full Text Available Duplications play a significant role in both extremes of the phenotypic spectrum of newly arising mutations: they can have severe deleterious effects (e.g. duplications underlie a variety of diseases but can also be highly advantageous. The phenotypic potential of newly arisen duplications has stimulated wide interest in both the mutational and selective processes shaping these variants in the genome. Here we take advantage of the Drosophila simulans-Drosophila melanogaster genetic system to further our understanding of both processes. Regarding mutational processes, the study of two closely related species allows investigation of the potential existence of shared duplication hotspots, and the similarities and differences between the two genomes can be used to dissect its underlying causes. Regarding selection, the difference in the effective population size between the two species can be leveraged to ask questions about the strength of selection acting on different classes of duplications. In this study, we conducted a survey of duplication polymorphisms in 14 different lines of D. simulans using tiling microarrays and combined it with an analogous survey for the D. melanogaster genome. By integrating the two datasets, we identified duplication hotspots conserved between the two species. However, unlike the duplication hotspots identified in mammalian genomes, Drosophila duplication hotspots are not associated with sequences of high sequence identity capable of mediating non-allelic homologous recombination. Instead, Drosophila duplication hotspots are associated with late-replicating regions of the genome, suggesting a link between DNA replication and duplication rates. We also found evidence supporting a higher effectiveness of selection on duplications in D. simulans than in D. melanogaster. This is also true for duplications segregating at high frequency, where we find evidence in D. simulans that a sizeable fraction of these mutations is

Replication the association of 2q32.2-q32.3 and 14q32.11 with hepatocellular carcinoma.

Science.gov (United States)

Chen, Wei; Wang, Mingquan; Zhang, Zhen; Tang, Huayang; Zuo, Xianbo; Meng, Xiangling; Xiong, Maoming; Zhou, Fusheng; Liang, Bo; Dai, Fen; Fang, Jun; Gao, Jinping; Zhu, Jun; Zhu, Yong; Wan, Hong; Wang, Miaofeng; Chan, Shixin; Sun, Liangdan

2015-04-25

Hepatocellular carcinoma (HCC) is a malignant tumor. The morbidity and mortality of HCC tend to ascend and become a serious threat to the population health. Genetic studies of HCC have identified several susceptibility loci of HCC. In this study, we aim to replicate the association of these loci in our samples from Chinese population and further investigate the genetic interaction. We selected 16 SNPs within 1p36.22, 2q32.2-q32.3, 3p21.33, 8p12, 14q32.11 and 21q21.3 and genotyped in 507 HCC patients and 3014 controls by using Sequenom MassARRAY system. Association analyses were performed by using PLINK 1.07. We observed that the STAT4 (2q32.2-q32.3) at rs7574865 (P=1.17×10(-3), OR=0.79) and EFCAB11 (14q32.11) at rs8013403 (P=1.54×10(-3), OR=0.80) were significantly associated with HCC in this study. In 3p21.33, genetic variant rs6795737 within GLB1 was also observed with suggestive evidence (P=9.98×10(-3), OR=0.84). In the interaction analysis, the pair of associated SNPs (rs7574865 within STAT4, rs8013403 within EFCAB11) generated evidence for interaction (P=4.10×10(-3)). In summary, our work first reported the association of 14q32.11 (EFCAB11) with HCC in Chinese Han population and revealed the genetic interaction between STAT4 (2q32.2-q32.3) and EFCAB11 (14q32.11) in HCC. Copyright © 2015 Elsevier B.V. All rights reserved.

Primer-Independent DNA Synthesis by a Family B DNA Polymerase from Self-Replicating Mobile Genetic Elements

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Modesto Redrejo-Rodríguez

2017-11-01

Full Text Available Family B DNA polymerases (PolBs play a central role during replication of viral and cellular chromosomes. Here, we report the discovery of a third major group of PolBs, which we denote primer-independent PolB (piPolB, that might be a link between the previously known protein-primed and RNA/DNA-primed PolBs. PiPolBs are encoded by highly diverse mobile genetic elements, pipolins, integrated in the genomes of diverse bacteria and also present as circular plasmids in mitochondria. Biochemical characterization showed that piPolB displays efficient DNA polymerization activity that can use undamaged and damaged templates and is endowed with proofreading and strand displacement capacities. Remarkably, the protein is also capable of template-dependent de novo DNA synthesis, i.e., DNA-priming activity, thereby breaking the long-standing dogma that replicative DNA polymerases require a pre-existing primer for DNA synthesis. We suggest that piPolBs are involved in self-replication of pipolins and may also contribute to bacterial DNA damage tolerance.

GWA study data mining and independent replication identify cardiomyopathy-associated 5 (CMYA5) as a risk gene for schizophrenia.

LENUS (Irish Health Repository)

Chen, X

2011-11-01

We conducted data-mining analyses using the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) and molecular genetics of schizophrenia genome-wide association study supported by the genetic association information network (MGS-GAIN) schizophrenia data sets and performed bioinformatic prioritization for all the markers with P-values ≤0.05 in both data sets. In this process, we found that in the CMYA5 gene, there were two non-synonymous markers, rs3828611 and rs10043986, showing nominal significance in both the CATIE and MGS-GAIN samples. In a combined analysis of both the CATIE and MGS-GAIN samples, rs4704591 was identified as the most significant marker in the gene. Linkage disequilibrium analyses indicated that these markers were in low LD (3 828 611-rs10043986, r(2)=0.008; rs10043986-rs4704591, r(2)=0.204). In addition, CMYA5 was reported to be physically interacting with the DTNBP1 gene, a promising candidate for schizophrenia, suggesting that CMYA5 may be involved in the same biological pathway and process. On the basis of this information, we performed replication studies for these three single-nucleotide polymorphisms. The rs3828611 was found to have conflicting results in our Irish samples and was dropped out without further investigation. The other two markers were verified in 23 other independent data sets. In a meta-analysis of all 23 replication samples (family samples, 912 families with 4160 subjects; case-control samples, 11 380 cases and 15 021 controls), we found that both markers are significantly associated with schizophrenia (rs10043986, odds ratio (OR)=1.11, 95% confidence interval (CI)=1.04-1.18, P=8.2 × 10(-4) and rs4704591, OR=1.07, 95% CI=1.03-1.11, P=3.0 × 10(-4)). The results were also significant for the 22 Caucasian replication samples (rs10043986, OR=1.11, 95% CI=1.03-1.17, P=0.0026 and rs4704591, OR=1.07, 95% CI=1.02-1.11, P=0.0015). Furthermore, haplotype conditioned analyses indicated that the association

Association between common variants near LBX1 and adolescent idiopathic scoliosis replicated in the Chinese Han population.

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Wenjie Gao

Full Text Available BACKGROUND: Adolescent idiopathic scoliosis (AIS is one of the most common spinal deformities found in adolescent populations. Recently, a genome-wide association study (GWAS in a Japanese population indicated that three single nucleotide polymorphisms (SNPs, rs11190870, rs625039 and rs11598564, all located near the LBX1 gene, may be associated with AIS susceptibility [1]. This study suggests a novel AIS predisposition candidate gene and supports the hypothesis that somatosensory functional disorders could contribute to the pathogenesis of AIS. These findings warrant replication in other populations. METHODOLOGY/PRINCIPAL FINDINGS: First, we conducted a case-control study consisting of 953 Chinese Han individuals from southern China (513 patients and 440 healthy controls, and the three SNPs were all found to be associated with AIS predisposition. The ORs were observed as 1.49 (95% CI 1.23-1.80, P = 5.09E-5, 1.70 (95% CI 1.42-2.04, P = 1.17E-8 and 1.52 (95% CI 1.27-1.83, P = 5.54E-6 for rs625039, rs11190870 and rs11598564, respectively. Second, a case-only study including a subgroup of AIS patients (N = 234 was performed to determine the effects of these variants on the severity of the condition. However, we did not find any association between these variants and the severity of curvature. CONCLUSION: This study shows that the genetic variants near the LBX1 gene are associated with AIS susceptibility in Chinese Han population. It successfully replicates the results of the GWAS, which was performed in a Japanese population.

Analysis of DNA replication associated chromatin decondensation: in vivo assay for understanding chromatin remodeling mechanisms of selected proteins.

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Borysov, Sergiy; Bryant, Victoria L; Alexandrow, Mark G

2015-01-01

Of critical importance to many of the events underlying transcriptional control of gene expression are modifications to core and linker histones that regulate the accessibility of trans-acting factors to the DNA substrate within the context of chromatin. Likewise, control over the initiation of DNA replication, as well as the ability of the replication machinery to proceed during elongation through the multiple levels of chromatin condensation that are likely to be encountered, is known to involve the creation of chromatin accessibility. In the latter case, chromatin access will likely need to be a transient event so as to prevent total genomic unraveling of the chromatin that would be deleterious to cells. While there are many molecular and biochemical approaches in use to study histone changes and their relationship to transcription and chromatin accessibility, few techniques exist that allow a molecular dissection of the events underlying DNA replication control as it pertains to chromatin changes and accessibility. Here, we outline a novel experimental strategy for addressing the ability of specific proteins to induce large-scale chromatin unfolding (decondensation) in vivo upon site-specific targeting to an engineered locus. Our laboratory has used this powerful system in novel ways to directly address the ability of DNA replication proteins to create chromatin accessibility, and have incorporated modifications to the basic approach that allow for a molecular genetic analysis of the mechanisms and associated factors involved in causing chromatin decondensation by a protein of interest. Alternative approaches involving co-expression of other proteins (competitors or stimulators), concurrent drug treatments, and analysis of co-localizing histone modifications are also addressed, all of which are illustrative of the utility of this experimental system for extending basic findings to physiologically relevant mechanisms. Although used by our group to analyze

Identification of Host Cell Factors Associated with Astrovirus Replication in Caco-2 Cells.

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Murillo, Andrea; Vera-Estrella, Rosario; Barkla, Bronwyn J; Méndez, Ernesto; Arias, Carlos F

2015-10-01

Astroviruses are small, nonenveloped viruses with a single-stranded positive-sense RNA genome causing acute gastroenteritis in children and immunocompromised patients. Since positive-sense RNA viruses have frequently been found to replicate in association with membranous structures, in this work we characterized the replication of the human astrovirus serotype 8 strain Yuc8 in Caco-2 cells, using density gradient centrifugation and free-flow zonal electrophoresis (FFZE) to fractionate cellular membranes. Structural and nonstructural viral proteins, positive- and negative-sense viral RNA, and infectious virus particles were found to be associated with a distinct population of membranes separated by FFZE. The cellular proteins associated with this membrane population in infected and mock-infected cells were identified by tandem mass spectrometry. The results indicated that membranes derived from multiple cell organelles were present in the population. Gene ontology and protein-protein interaction network analysis showed that groups of proteins with roles in fatty acid synthesis and ATP biosynthesis were highly enriched in the fractions of this population in infected cells. Based on this information, we investigated by RNA interference the role that some of the identified proteins might have in the replication cycle of the virus. Silencing of the expression of genes involved in cholesterol (DHCR7, CYP51A1) and fatty acid (FASN) synthesis, phosphatidylinositol (PI4KIIIβ) and inositol phosphate (ITPR3) metabolism, and RNA helicase activity (DDX23) significantly decreased the amounts of Yuc8 genomic and antigenomic RNA, synthesis of the structural protein VP90, and virus yield. These results strongly suggest that astrovirus RNA replication and particle assembly take place in association with modified membranes potentially derived from multiple cell organelles. Astroviruses are common etiological agents of acute gastroenteritis in children and immunocompromised patients

Identification of Host Cell Factors Associated with Astrovirus Replication in Caco-2 Cells

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Murillo, Andrea; Vera-Estrella, Rosario; Barkla, Bronwyn J.; Méndez, Ernesto

2015-01-01

ABSTRACT Astroviruses are small, nonenveloped viruses with a single-stranded positive-sense RNA genome causing acute gastroenteritis in children and immunocompromised patients. Since positive-sense RNA viruses have frequently been found to replicate in association with membranous structures, in this work we characterized the replication of the human astrovirus serotype 8 strain Yuc8 in Caco-2 cells, using density gradient centrifugation and free-flow zonal electrophoresis (FFZE) to fractionate cellular membranes. Structural and nonstructural viral proteins, positive- and negative-sense viral RNA, and infectious virus particles were found to be associated with a distinct population of membranes separated by FFZE. The cellular proteins associated with this membrane population in infected and mock-infected cells were identified by tandem mass spectrometry. The results indicated that membranes derived from multiple cell organelles were present in the population. Gene ontology and protein-protein interaction network analysis showed that groups of proteins with roles in fatty acid synthesis and ATP biosynthesis were highly enriched in the fractions of this population in infected cells. Based on this information, we investigated by RNA interference the role that some of the identified proteins might have in the replication cycle of the virus. Silencing of the expression of genes involved in cholesterol (DHCR7, CYP51A1) and fatty acid (FASN) synthesis, phosphatidylinositol (PI4KIIIβ) and inositol phosphate (ITPR3) metabolism, and RNA helicase activity (DDX23) significantly decreased the amounts of Yuc8 genomic and antigenomic RNA, synthesis of the structural protein VP90, and virus yield. These results strongly suggest that astrovirus RNA replication and particle assembly take place in association with modified membranes potentially derived from multiple cell organelles. IMPORTANCE Astroviruses are common etiological agents of acute gastroenteritis in children and

Genome-wide association study of triglyceride response to a high-fat meal among participants of the NHLBI Genetics of Lipid Lowering Drugs and Diet Network (GOLDN).

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Wojczynski, Mary K; Parnell, Laurence D; Pollin, Toni I; Lai, Chao Q; Feitosa, Mary F; O'Connell, Jeff R; Frazier-Wood, Alexis C; Gibson, Quince; Aslibekyan, Stella; Ryan, Kathy A; Province, Michael A; Tiwari, Hemant K; Ordovas, Jose M; Shuldiner, Alan R; Arnett, Donna K; Borecki, Ingrid B

2015-10-01

The triglyceride (TG) response to a high-fat meal (postprandial lipemia, PPL) affects cardiovascular disease risk and is influenced by genes and environment. Genes involved in lipid metabolism have dominated genetic studies of PPL TG response. We sought to elucidate common genetic variants through a genome-wide association (GWA) study in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN). The GOLDN GWAS discovery sample consisted of 872 participants within families of European ancestry. Genotypes for 2,543,887 variants were measured or imputed from HapMap. Replication of our top results was performed in the Heredity and Phenotype Intervention (HAPI) Heart Study (n = 843). PPL TG response phenotypes were constructed from plasma TG measured at baseline (fasting, 0 hour), 3.5 and 6 hours after a high-fat meal, using a random coefficient regression model. Association analyses were adjusted for covariates and principal components, as necessary, in a linear mixed model using the kinship matrix; additional models further adjusted for fasting TG were also performed. Meta-analysis of the discovery and replication studies (n = 1715) was performed on the top SNPs from GOLDN. GOLDN revealed 111 suggestive (p 5E-08). Of the two significant SNPs, rs964184 demonstrated evidence of replication (p = 1.20E-03) in the HAPI Heart Study and in a joint analysis, was GWA significant (p = 1.26E-09). Rs964184 has been associated with fasting lipids (TG and HDL) and is near ZPR1 (formerly ZNF259), close to the APOA1/C3/A4/A5 cluster. This association was attenuated upon additional adjustment for fasting TG. This is the first report of a genome-wide significant association with replication for a novel phenotype, namely PPL TG response. Future investigation into response phenotypes is warranted using pathway analyses, or newer genetic technologies such as metabolomics. Copyright © 2015 Elsevier Inc. All rights reserved.

Using Y-Chromosomal Haplogroups in Genetic Association Studies and Suggested Implications.

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Erzurumluoglu, A Mesut; Baird, Denis; Richardson, Tom G; Timpson, Nicholas J; Rodriguez, Santiago

2018-01-22

Y-chromosomal (Y-DNA) haplogroups are more widely used in population genetics than in genetic epidemiology, although associations between Y-DNA haplogroups and several traits, including cardiometabolic traits, have been reported. In apparently homogeneous populations defined by principal component analyses, there is still Y-DNA haplogroup variation which will result from population history. Therefore, hidden stratification and/or differential phenotypic effects by Y-DNA haplogroups could exist. To test this, we hypothesised that stratifying individuals according to their Y-DNA haplogroups before testing for associations between autosomal single nucleotide polymorphisms (SNPs) and phenotypes will yield difference in association. For proof of concept, we derived Y-DNA haplogroups from 6537 males from two epidemiological cohorts, Avon Longitudinal Study of Parents and Children (ALSPAC) ( n = 5080; 816 Y-DNA SNPs) and the 1958 Birth Cohort ( n = 1457; 1849 Y-DNA SNPs), and studied the robust associations between 32 SNPs and body mass index (BMI), including SNPs in or near Fat Mass and Obesity-associated protein ( FTO ) which yield the strongest effects. Overall, no association was replicated in both cohorts when Y-DNA haplogroups were considered and this suggests that, for BMI at least, there is little evidence of differences in phenotype or SNP association by Y-DNA structure. Further studies using other traits, phenome-wide association studies (PheWAS), other haplogroups and/or autosomal SNPs are required to test the generalisability and utility of this approach.

Mechanisms of bacterial DNA replication restart

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Windgassen, Tricia A; Wessel, Sarah R; Bhattacharyya, Basudeb

2018-01-01

Abstract Multi-protein DNA replication complexes called replisomes perform the essential process of copying cellular genetic information prior to cell division. Under ideal conditions, replisomes dissociate only after the entire genome has been duplicated. However, DNA replication rarely occurs without interruptions that can dislodge replisomes from DNA. Such events produce incompletely replicated chromosomes that, if left unrepaired, prevent the segregation of full genomes to daughter cells. To mitigate this threat, cells have evolved ‘DNA replication restart’ pathways that have been best defined in bacteria. Replication restart requires recognition and remodeling of abandoned replication forks by DNA replication restart proteins followed by reloading of the replicative DNA helicase, which subsequently directs assembly of the remaining replisome subunits. This review summarizes our current understanding of the mechanisms underlying replication restart and the proteins that drive the process in Escherichia coli (PriA, PriB, PriC and DnaT). PMID:29202195

Statistical correction of the Winner's Curse explains replication variability in quantitative trait genome-wide association studies.

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Cameron Palmer

2017-07-01

Full Text Available Genome-wide association studies (GWAS have identified hundreds of SNPs responsible for variation in human quantitative traits. However, genome-wide-significant associations often fail to replicate across independent cohorts, in apparent inconsistency with their apparent strong effects in discovery cohorts. This limited success of replication raises pervasive questions about the utility of the GWAS field. We identify all 332 studies of quantitative traits from the NHGRI-EBI GWAS Database with attempted replication. We find that the majority of studies provide insufficient data to evaluate replication rates. The remaining papers replicate significantly worse than expected (p < 10-14, even when adjusting for regression-to-the-mean of effect size between discovery- and replication-cohorts termed the Winner's Curse (p < 10-16. We show this is due in part to misreporting replication cohort-size as a maximum number, rather than per-locus one. In 39 studies accurately reporting per-locus cohort-size for attempted replication of 707 loci in samples with similar ancestry, replication rate matched expectation (predicted 458, observed 457, p = 0.94. In contrast, ancestry differences between replication and discovery (13 studies, 385 loci cause the most highly-powered decile of loci to replicate worse than expected, due to difference in linkage disequilibrium.

Eukaryotic DNA Replication Fork.

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Burgers, Peter M J; Kunkel, Thomas A

2017-06-20

This review focuses on the biogenesis and composition of the eukaryotic DNA replication fork, with an emphasis on the enzymes that synthesize DNA and repair discontinuities on the lagging strand of the replication fork. Physical and genetic methodologies aimed at understanding these processes are discussed. The preponderance of evidence supports a model in which DNA polymerase ε (Pol ε) carries out the bulk of leading strand DNA synthesis at an undisturbed replication fork. DNA polymerases α and δ carry out the initiation of Okazaki fragment synthesis and its elongation and maturation, respectively. This review also discusses alternative proposals, including cellular processes during which alternative forks may be utilized, and new biochemical studies with purified proteins that are aimed at reconstituting leading and lagging strand DNA synthesis separately and as an integrated replication fork.

Replicating chromatin: a tale of histones

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Groth, Anja

2009-01-01

Chromatin serves structural and functional roles crucial for genome stability and correct gene expression. This organization must be reproduced on daughter strands during replication to maintain proper overlay of epigenetic fabric onto genetic sequence. Nucleosomes constitute the structural...... framework of chromatin and carry information to specify higher-order organization and gene expression. When replication forks traverse the chromosomes, nucleosomes are transiently disrupted, allowing the replication machinery to gain access to DNA. Histone recycling, together with new deposition, ensures...

Effects of genetic variants previously associated with fasting glucose and insulin in the Diabetes Prevention Program.

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Jose C Florez

Full Text Available Common genetic variants have been recently associated with fasting glucose and insulin levels in white populations. Whether these associations replicate in pre-diabetes is not known. We extended these findings to the Diabetes Prevention Program, a clinical trial in which participants at high risk for diabetes were randomized to placebo, lifestyle modification or metformin for diabetes prevention. We genotyped previously reported polymorphisms (or their proxies in/near G6PC2, MTNR1B, GCK, DGKB, GCKR, ADCY5, MADD, CRY2, ADRA2A, FADS1, PROX1, SLC2A2, GLIS3, C2CD4B, IGF1, and IRS1 in 3,548 Diabetes Prevention Program participants. We analyzed variants for association with baseline glycemic traits, incident diabetes and their interaction with response to metformin or lifestyle intervention. We replicated associations with fasting glucose at MTNR1B (P<0.001, G6PC2 (P = 0.002 and GCKR (P = 0.001. We noted impaired β-cell function in carriers of glucose-raising alleles at MTNR1B (P<0.001, and an increase in the insulinogenic index for the glucose-raising allele at G6PC2 (P<0.001. The association of MTNR1B with fasting glucose and impaired β-cell function persisted at 1 year despite adjustment for the baseline trait, indicating a sustained deleterious effect at this locus. We also replicated the association of MADD with fasting proinsulin levels (P<0.001. We detected no significant impact of these variants on diabetes incidence or interaction with preventive interventions. The association of several polymorphisms with quantitative glycemic traits is replicated in a cohort of high-risk persons. These variants do not have a detectable impact on diabetes incidence or response to metformin or lifestyle modification in the Diabetes Prevention Program.

Strand-Specific Analysis of DNA Synthesis and Proteins Association with DNA Replication Forks in Budding Yeast.

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Yu, Chuanhe; Gan, Haiyun; Zhang, Zhiguo

2018-01-01

DNA replication initiates at DNA replication origins after unwinding of double-strand DNA(dsDNA) by replicative helicase to generate single-stranded DNA (ssDNA) templates for the continuous synthesis of leading-strand and the discontinuous synthesis of lagging-strand. Therefore, methods capable of detecting strand-specific information will likely yield insight into the association of proteins at leading and lagging strand of DNA replication forks and the regulation of leading and lagging strand synthesis during DNA replication. The enrichment and Sequencing of Protein-Associated Nascent DNA (eSPAN), which measure the relative amounts of proteins at nascent leading and lagging strands of DNA replication forks, is a step-wise procedure involving the chromatin immunoprecipitation (ChIP) of a protein of interest followed by the enrichment of protein-associated nascent DNA through BrdU immunoprecipitation. The isolated ssDNA is then subjected to strand-specific sequencing. This method can detect whether a protein is enriched at leading or lagging strand of DNA replication forks. In addition to eSPAN, two other strand-specific methods, (ChIP-ssSeq), which detects potential protein-ssDNA binding and BrdU-IP-ssSeq, which can measure synthesis of both leading and lagging strand, were developed along the way. These methods can provide strand-specific and complementary information about the association of the target protein with DNA replication forks as well as synthesis of leading and lagging strands genome wide. Below, we describe the detailed eSPAN, ChIP-ssSeq, and BrdU-IP-ssSeq protocols.

Replicated Risk Nicotinic Cholinergic Receptor Genes for Nicotine Dependence

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Lingjun Zuo

2016-11-01

Full Text Available It has been hypothesized that the nicotinic acetylcholine receptors (nAChRs play important roles in nicotine dependence (ND and influence the number of cigarettes smoked per day (CPD in smokers. We compiled the associations between nicotinic cholinergic receptor genes (CHRNs and ND/CPD that were replicated across different studies, reviewed the expression of these risk genes in human/mouse brains, and verified their expression using independent samples of both human and mouse brains. The potential functions of the replicated risk variants were examined using cis-eQTL analysis or predicted using a series of bioinformatics analyses. We found replicated and significant associations for ND/CPD at 19 SNPs in six genes in three genomic regions (CHRNB3-A6, CHRNA5-A3-B4 and CHRNA4. These six risk genes are expressed in at least 18 distinct areas of the human/mouse brain, with verification in our independent human and mouse brain samples. The risk variants might influence the transcription, expression and splicing of the risk genes, alter RNA secondary or protein structure. We conclude that the replicated associations between CHRNB3-A6, CHRNA5-A3-B4, CHRNA4 and ND/CPD are very robust. More research is needed to examine how these genetic variants contribute to the risk for ND/CPD.

Genetically Thermo-Stabilised, Immunogenic Poliovirus Empty Capsids; a Strategy for Non-replicating Vaccines.

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Helen Fox

2017-01-01

Full Text Available While wild type polio has been nearly eradicated there will be a need to continue immunisation programmes for some time because of the possibility of re-emergence and the existence of long term excreters of poliovirus. All vaccines in current use depend on growth of virus and most of the non-replicating (inactivated vaccines involve wild type viruses known to cause poliomyelitis. The attenuated vaccine strains involved in the eradication programme have been used to develop new inactivated vaccines as production is thought safer. However it is known that the Sabin vaccine strains are genetically unstable and can revert to a virulent transmissible form. A possible solution to the need for virus growth would be to generate empty viral capsids by recombinant technology, but hitherto such particles are so unstable as to be unusable. We report here the genetic manipulation of the virus to generate stable empty capsids for all three serotypes. The particles are shown to be extremely stable and to generate high levels of protective antibodies in animal models.

Peer Influence, Genetic Propensity, and Binge Drinking: A Natural Experiment and a Replication.

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Guo, Guang; Li, Yi; Wang, Hongyu; Cai, Tianji; Duncan, Greg J

2015-11-01

The authors draw data from the College Roommate Study (ROOM) and the National Longitudinal Study of Adolescent Health to investigate gene-environment interaction effects on youth binge drinking. In ROOM, the environmental influence was measured by the precollege drinking behavior of randomly assigned roommates. Random assignment safeguards against friend selection and removes the threat of gene-environment correlation that makes gene-environment interaction effects difficult to interpret. On average, being randomly assigned a drinking peer as opposed to a nondrinking peer increased college binge drinking by 0.5-1.0 episodes per month, or 20%-40% the average amount of binge drinking. However, this peer influence was found only among youths with a medium level of genetic propensity for alcohol use; those with either a low or high genetic propensity were not influenced by peer drinking. A replication of the findings is provided in data drawn from Add Health. The study shows that gene-environment interaction analysis can uncover social-contextual effects likely to be missed by traditional sociological approaches.

Transcriptionally Driven DNA Replication Program of the Human Parasite Leishmania major.

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Lombraña, Rodrigo; Álvarez, Alba; Fernández-Justel, José Miguel; Almeida, Ricardo; Poza-Carrión, César; Gomes, Fábia; Calzada, Arturo; Requena, José María; Gómez, María

2016-08-09

Faithful inheritance of eukaryotic genomes requires the orchestrated activation of multiple DNA replication origins (ORIs). Although origin firing is mechanistically conserved, how origins are specified and selected for activation varies across different model systems. Here, we provide a complete analysis of the nucleosomal landscape and replication program of the human parasite Leishmania major, building on a better evolutionary understanding of replication organization in Eukarya. We found that active transcription is a driving force for the nucleosomal organization of the L. major genome and that both the spatial and the temporal program of DNA replication can be explained as associated to RNA polymerase kinetics. This simple scenario likely provides flexibility and robustness to deal with the environmental changes that impose alterations in the genetic programs during parasitic life cycle stages. Our findings also suggest that coupling replication initiation to transcription elongation could be an ancient solution used by eukaryotic cells for origin maintenance. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Transcriptionally Driven DNA Replication Program of the Human Parasite Leishmania major

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Rodrigo Lombraña

2016-08-01

Full Text Available Faithful inheritance of eukaryotic genomes requires the orchestrated activation of multiple DNA replication origins (ORIs. Although origin firing is mechanistically conserved, how origins are specified and selected for activation varies across different model systems. Here, we provide a complete analysis of the nucleosomal landscape and replication program of the human parasite Leishmania major, building on a better evolutionary understanding of replication organization in Eukarya. We found that active transcription is a driving force for the nucleosomal organization of the L. major genome and that both the spatial and the temporal program of DNA replication can be explained as associated to RNA polymerase kinetics. This simple scenario likely provides flexibility and robustness to deal with the environmental changes that impose alterations in the genetic programs during parasitic life cycle stages. Our findings also suggest that coupling replication initiation to transcription elongation could be an ancient solution used by eukaryotic cells for origin maintenance.

Stalled replication forks generate a distinct mutational signature in yeast

DEFF Research Database (Denmark)

Larsen, Nicolai B.; Liberti, Sascha E.; Vogel, Ivan

2017-01-01

Proliferating cells acquire genome alterations during the act of DNA replication. This leads to mutation accumulation and somatic cell mosaicism in multicellular organisms, and is also implicated as an underlying cause of aging and tumorigenesis. The molecular mechanisms of DNA replication...... Escherichia coli Tus/Ter complex) engineered into the yeast genome. We demonstrate that transient stalling at this barrier induces a distinct pattern of genome rearrangements in the newly replicated region behind the stalled fork, which primarily consist of localized losses and duplications of DNA sequences....... These genetic alterations arise through the aberrant repair of a single-stranded DNA gap, in a process that is dependent on Exo1- and Shu1-dependent homologous recombination repair (HRR). Furthermore, aberrant processing of HRR intermediates, and elevated HRR-associated mutagenesis, is detectable in a yeast...

Oncolytic Replication of E1b-Deleted Adenoviruses

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Pei-Hsin Cheng

2015-11-01

Full Text Available Various viruses have been studied and developed for oncolytic virotherapies. In virotherapy, a relatively small amount of viruses used in an intratumoral injection preferentially replicate in and lyse cancer cells, leading to the release of amplified viral particles that spread the infection to the surrounding tumor cells and reduce the tumor mass. Adenoviruses (Ads are most commonly used for oncolytic virotherapy due to their infection efficacy, high titer production, safety, easy genetic modification, and well-studied replication characteristics. Ads with deletion of E1b55K preferentially replicate in and destroy cancer cells and have been used in multiple clinical trials. H101, one of the E1b55K-deleted Ads, has been used for the treatment of late-stage cancers as the first approved virotherapy agent. However, the mechanism of selective replication of E1b-deleted Ads in cancer cells is still not well characterized. This review will focus on three potential molecular mechanisms of oncolytic replication of E1b55K-deleted Ads. These mechanisms are based upon the functions of the viral E1B55K protein that are associated with p53 inhibition, late viralmRNAexport, and cell cycle disruption.

Genetic variants associated with subjective well-being, depressive symptoms and neuroticism identified through genome-wide analyses

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Derringer, Jaime; Gratten, Jacob; Lee, James J; Liu, Jimmy Z; de Vlaming, Ronald; Ahluwalia, Tarunveer S; Buchwald, Jadwiga; Cavadino, Alana; Frazier-Wood, Alexis C; Davies, Gail; Furlotte, Nicholas A; Garfield, Victoria; Geisel, Marie Henrike; Gonzalez, Juan R; Haitjema, Saskia; Karlsson, Robert; van der Laan, Sander W; Ladwig, Karl-Heinz; Lahti, Jari; van der Lee, Sven J; Miller, Michael B; Lind, Penelope A; Liu, Tian; Matteson, Lindsay; Mihailov, Evelin; Minica, Camelia C; Nolte, Ilja M; Mook-Kanamori, Dennis O; van der Most, Peter J; Oldmeadow, Christopher; Qian, Yong; Raitakari, Olli; Rawal, Rajesh; Realo, Anu; Rueedi, Rico; Schmidt, Börge; Smith, Albert V; Stergiakouli, Evie; Tanaka, Toshiko; Taylor, Kent; Thorleifsson, Gudmar; Wedenoja, Juho; Wellmann, Juergen; Westra, Harm-Jan; Willems, Sara M; Zhao, Wei; Amin, Najaf; Bakshi, Andrew; Bergmann, Sven; Bjornsdottir, Gyda; Boyle, Patricia A; Cherney, Samantha; Cox, Simon R; Davis, Oliver S P; Ding, Jun; Direk, Nese; Eibich, Peter; Emeny, Rebecca T; Fatemifar, Ghazaleh; Faul, Jessica D; Ferrucci, Luigi; Forstner, Andreas J; Gieger, Christian; Gupta, Richa; Harris, Tamara B; Harris, Juliette M; Holliday, Elizabeth G; Hottenga, Jouke-Jan; De Jager, Philip L; Kaakinen, Marika A; Kajantie, Eero; Karhunen, Ville; Kolcic, Ivana; Kumari, Meena; Launer, Lenore J; Franke, Lude; Li-Gao, Ruifang; Liewald, David C; Koini, Marisa; Loukola, Anu; Marques-Vidal, Pedro; Montgomery, Grant W; Mosing, Miriam A; Paternoster, Lavinia; Pattie, Alison; Petrovic, Katja E; Pulkki-Råback, Laura; Quaye, Lydia; Räikkönen, Katri; Rudan, Igor; Scott, Rodney J; Smith, Jennifer A; Sutin, Angelina R; Trzaskowski, Maciej; Vinkhuyzen, Anna E; Yu, Lei; Zabaneh, Delilah; Attia, John R; Bennett, David A; Berger, Klaus; Bertram, Lars; Boomsma, Dorret I; Snieder, Harold; Chang, Shun-Chiao; Cucca, Francesco; Deary, Ian J; van Duijn, Cornelia M; Eriksson, Johan G; Bültmann, Ute; de Geus, Eco J C; Groenen, Patrick J F; Gudnason, Vilmundur; Hansen, Torben; Hartman, Catharine A; Haworth, Claire M A; Hayward, Caroline; Heath, Andrew C; Hinds, David A; Hyppönen, Elina; Iacono, William G; Järvelin, Marjo-Riitta; Jöckel, Karl-Heinz; Kaprio, Jaakko; Kardia, Sharon L R; Keltikangas-Järvinen, Liisa; Kraft, Peter; Kubzansky, Laura D; Lehtimäki, Terho; Magnusson, Patrik K E; Martin, Nicholas G; McGue, Matt; Metspalu, Andres; Mills, Melinda; de Mutsert, Renée; Oldehinkel, Albertine J; Pasterkamp, Gerard; Pedersen, Nancy L; Plomin, Robert; Polasek, Ozren; Power, Christine; Rich, Stephen S; Rosendaal, Frits R; den Ruijter, Hester M; Schlessinger, David; Schmidt, Helena; Svento, Rauli; Schmidt, Reinhold; Alizadeh, Behrooz Z; Sørensen, Thorkild I A; Spector, Tim D; Starr, John M; Stefansson, Kari; Steptoe, Andrew; Terracciano, Antonio; Thorsteinsdottir, Unnur; Thurik, A Roy; Timpson, Nicholas J; Tiemeier, Henning; Uitterlinden, André G; Vollenweider, Peter; Wagner, Gert G; Weir, David R; Yang, Jian; Conley, Dalton C; Smith, George Davey; Hofman, Albert; Johannesson, Magnus; Laibson, David I; Medland, Sarah E; Meyer, Michelle N; Pickrell, Joseph K; Esko, Tõnu; Krueger, Robert F; Beauchamp, Jonathan P; Koellinger, Philipp D; Benjamin, Daniel J; Bartels, Meike; Cesarini, David

2016-01-01

We conducted genome-wide association studies of three phenotypes: subjective well-being (N = 298,420), depressive symptoms (N = 161,460), and neuroticism (N = 170,910). We identified three variants associated with subjective well-being, two with depressive symptoms, and eleven with neuroticism, including two inversion polymorphisms. The two depressive symptoms loci replicate in an independent depression sample. Joint analyses that exploit the high genetic correlations between the phenotypes (|ρ^| ≈ 0.8) strengthen the overall credibility of the findings, and allow us to identify additional variants. Across our phenotypes, loci regulating expression in central nervous system and adrenal/pancreas tissues are strongly enriched for association. PMID:27089181

Genetic association study identifies HSPB7 as a risk gene for idiopathic dilated cardiomyopathy.

Directory of Open Access Journals (Sweden)

Klaus Stark

2010-10-01

Full Text Available Dilated cardiomyopathy (DCM is a structural heart disease with strong genetic background. Monogenic forms of DCM are observed in families with mutations located mostly in genes encoding structural and sarcomeric proteins. However, strong evidence suggests that genetic factors also affect the susceptibility to idiopathic DCM. To identify risk alleles for non-familial forms of DCM, we carried out a case-control association study, genotyping 664 DCM cases and 1,874 population-based healthy controls from Germany using a 50K human cardiovascular disease bead chip covering more than 2,000 genes pre-selected for cardiovascular relevance. After quality control, 30,920 single nucleotide polymorphisms (SNP were tested for association with the disease by logistic regression adjusted for gender, and results were genomic-control corrected. The analysis revealed a significant association between a SNP in HSPB7 gene (rs1739843, minor allele frequency 39% and idiopathic DCM (p = 1.06 × 10⁻⁶, OR  = 0.67 [95% CI 0.57-0.79] for the minor allele T. Three more SNPs showed p < 2.21 × 10⁻⁵. De novo genotyping of these four SNPs was done in three independent case-control studies of idiopathic DCM. Association between SNP rs1739843 and DCM was significant in all replication samples: Germany (n =564, n = 981 controls, p = 2.07 × 10⁻³, OR = 0.79 [95% CI 0.67-0.92], France 1 (n = 433 cases, n = 395 controls, p =3.73 × 10⁻³, OR  = 0.74 [95% CI 0.60-0.91], and France 2 (n = 249 cases, n = 380 controls, p = 2.26 × 10⁻⁴, OR  = 0.63 [95% CI 0.50-0.81]. The combined analysis of all four studies including a total of n = 1,910 cases and n = 3,630 controls showed highly significant evidence for association between rs1739843 and idiopathic DCM (p = 5.28 × 10⁻¹³, OR= 0.72 [95% CI 0.65-0.78]. None of the other three SNPs showed significant results in the replication stage.This finding of the HSPB7 gene from a genetic search for idiopathic DCM using

Homologous recombination in mammalian cells: effect of p53 and Bcl-2 proteins, replication inhibition and ionizing radiations

International Nuclear Information System (INIS)

Saintigny, Yannick

1999-01-01

The control of cell cycle, associated with the mechanisms of replication, DNA repair/recombination allows the cells to maintain their genetic integrity. The p53 protein ensures the control of G1/S transition. Its inactivation would allow to initial replication on damaged matrix and lead to the block of replication forks followed by DNA strand breaks, good substrates for recombination. This work shows that the expression of mutant p53 protein stimulates both spontaneous and radio-induced homologous recombination, independently of the control of cell cycle. Moreover, the use of a set of replication inhibitors show that inhibition of the replication elongation stimulates recombination more strongly than the initiation inhibition. Replication arrest by these inhibitors also significantly increases the number of DNA strand breaks. These results highlighted a point of action of p53 protein on the ultimate stages of the homologous recombination mechanism. Lastly, the expression of Bcl-2 protein inhibits apoptosis and increases survival, but specifically inhibits conservative recombination, after radiation as well as in absence of apoptotic stress. The extinction of this mechanism of DNA repair is associated with an increase of mutagenesis. Taken together, these results allow ta consider the maintenance of the genetic stability as a cellular network involving different pathways. A multiple stages model for tumoral progression can be deduced. (author) [fr

Assessment of heterogeneity between European Populations: a Baltic and Danish replication case-control study of SNPs from a recent European ulcerative colitis genome wide association study.

Science.gov (United States)

Andersen, Vibeke; Ernst, Anja; Sventoraityte, Jurgita; Kupcinskas, Limas; Jacobsen, Bent A; Krarup, Henrik B; Vogel, Ulla; Jonaitis, Laimas; Denapiene, Goda; Kiudelis, Gediminas; Balschun, Tobias; Franke, Andre

2011-10-13

Differences in the genetic architecture of inflammatory bowel disease between different European countries and ethnicities have previously been reported. In the present study, we wanted to assess the role of 11 newly identified UC risk variants, derived from a recent European UC genome wide association study (GWAS) (Franke et al., 2010), for 1) association with UC in the Nordic countries, 2) for population heterogeneity between the Nordic countries and the rest of Europe, and, 3) eventually, to drive some of the previous findings towards overall genome-wide significance. Eleven SNPs were replicated in a Danish sample consisting of 560 UC patients and 796 controls and nine missing SNPs of the German GWAS study were successfully genotyped in the Baltic sample comprising 441 UC cases and 1156 controls. The independent replication data was then jointly analysed with the original data and systematic comparisons of the findings between ethnicities were made. Pearson's χ2, Breslow-Day (BD) and Cochran-Mantel-Haenszel (CMH) tests were used for association analyses and heterogeneity testing. The rs5771069 (IL17REL) SNP was not associated with UC in the Danish panel. The rs5771069 (IL17REL) SNP was significantly associated with UC in the combined Baltic, Danish and Norwegian UC study sample driven by the Norwegian panel (OR = 0.89, 95% CI: 0.79-0.98, P = 0.02). No association was found between rs7809799 (SMURF1/KPNA7) and UC (OR = 1.20, 95% CI: 0.95-1.52, P = 0.10) or between UC and all other remaining SNPs. We had 94% chance of detecting an association for rs7809799 (SMURF1/KPNA7) in the combined replication sample, whereas the power were 55% or lower for the remaining SNPs.Statistically significant PBD was found for OR heterogeneity between the combined Baltic, Danish, and Norwegian panel versus the combined German, British, Belgian, and Greek panel (rs7520292 (P = 0.001), rs12518307 (P = 0.007), and rs2395609 (TCP11) (P = 0.01), respectively).No SNP reached genome

Mapping autonomously replicating sequence elements in a 73-kb ...

Indian Academy of Sciences (India)

Autonomously replicating sequence (ARS) elements are the genetic determinants of replication origin function in yeasts. They can be easily identified as the plasmids containing them transform yeast cells at a high frequency. As the first step towards identifying all potential replication origins in a 73-kb region of the long arm ...

Functions of Ubiquitin and SUMO in DNA Replication and Replication Stress

Science.gov (United States)

García-Rodríguez, Néstor; Wong, Ronald P.; Ulrich, Helle D.

2016-01-01

Complete and faithful duplication of its entire genetic material is one of the essential prerequisites for a proliferating cell to maintain genome stability. Yet, during replication DNA is particularly vulnerable to insults. On the one hand, lesions in replicating DNA frequently cause a stalling of the replication machinery, as most DNA polymerases cannot cope with defective templates. This situation is aggravated by the fact that strand separation in preparation for DNA synthesis prevents common repair mechanisms relying on strand complementarity, such as base and nucleotide excision repair, from working properly. On the other hand, the replication process itself subjects the DNA to a series of hazardous transformations, ranging from the exposure of single-stranded DNA to topological contortions and the generation of nicks and fragments, which all bear the risk of inducing genomic instability. Dealing with these problems requires rapid and flexible responses, for which posttranslational protein modifications that act independently of protein synthesis are particularly well suited. Hence, it is not surprising that members of the ubiquitin family, particularly ubiquitin itself and SUMO, feature prominently in controlling many of the defensive and restorative measures involved in the protection of DNA during replication. In this review we will discuss the contributions of ubiquitin and SUMO to genome maintenance specifically as they relate to DNA replication. We will consider cases where the modifiers act during regular, i.e., unperturbed stages of replication, such as initiation, fork progression, and termination, but also give an account of their functions in dealing with lesions, replication stalling and fork collapse. PMID:27242895

Adeno-associated virus type 2 enhances goose parvovirus replication in embryonated goose eggs

International Nuclear Information System (INIS)

Malkinson, Mertyn; Winocour, Ernest

2005-01-01

The autonomous goose parvovirus (GPV) and the human helper-dependent adeno-associated virus type 2 (AAV2) share a high degree of homology. To determine if this evolutionary relationship has a biological impact, we studied viral replication in human 293 cells and in embryonated goose eggs coinfected with both viruses. Similar experiments were performed with the minute virus of mice (MVM), an autonomous murine parvovirus with less homology to AAV2. In human 293 cells, both GPV and MVM augmented AAV2 replication. In contrast, AAV2 markedly enhanced GPV replication in embryonated goose eggs under conditions where a similar effect was not observed with MVM. AAV2 did not replicate in embryonated goose eggs and AAV2 inactivated by UV-irradiation also enhanced GPV replication. To our knowledge, this is the first report that a human helper-dependent member of the Parvoviridae can provide helper activity for an autonomous parvovirus in a natural host

Genetic Influences on Conduct Disorder

Science.gov (United States)

Salvatore, Jessica E.; Dick, Danielle M.

2016-01-01

Conduct disorder (CD) is a moderately heritable psychiatric disorder of childhood and adolescence characterized by aggression toward people and animals, destruction of property, deceitfulness or theft, and serious violation of rules. Genome-wide scans using linkage and association methods have identified a number of suggestive genomic regions that are pending replication. A small number of candidate genes (e.g., GABRA2, MAOA, SLC6A4, AVPR1A) are associated with CD related phenotypes across independent studies; however, failures to replicate also exist. Studies of gene-environment interplay show that CD genetic predispositions also contribute to selection into higher-risk environments, and that environmental factors can alter the importance of CD genetic factors and differentially methylate CD candidate genes. The field’s understanding of CD etiology will benefit from larger, adequately powered studies in gene identification efforts; the incorporation of polygenic approaches in gene-environment interplay studies; attention to the mechanisms of risk from genes to brain to behavior; and the use of genetically informative data to test quasi-causal hypotheses about purported risk factors. PMID:27350097

Pervasive Sharing of Genetic Effects in Autoimmune Disease

DEFF Research Database (Denmark)

Cotsapas, Chris; Voight, Benjamin F.; Rossin, Elizabeth

2011-01-01

Genome-wide association (GWA) studies have identified numerous, replicable, genetic associations between common single nucleotide polymorphisms (SNPs) and risk of common autoimmune and inflammatory (immune-mediated) diseases, some of which are shared between two diseases. Along with epidemiologic...

Interpretation of genetic association studies: markers with replicated highly significant odds ratios may be poor classifiers.

Directory of Open Access Journals (Sweden)

Johanna Jakobsdottir

2009-02-01

Full Text Available Recent successful discoveries of potentially causal single nucleotide polymorphisms (SNPs for complex diseases hold great promise, and commercialization of genomics in personalized medicine has already begun. The hope is that genetic testing will benefit patients and their families, and encourage positive lifestyle changes and guide clinical decisions. However, for many complex diseases, it is arguable whether the era of genomics in personalized medicine is here yet. We focus on the clinical validity of genetic testing with an emphasis on two popular statistical methods for evaluating markers. The two methods, logistic regression and receiver operating characteristic (ROC curve analysis, are applied to our age-related macular degeneration dataset. By using an additive model of the CFH, LOC387715, and C2 variants, the odds ratios are 2.9, 3.4, and 0.4, with p-values of 10(-13, 10(-13, and 10(-3, respectively. The area under the ROC curve (AUC is 0.79, but assuming prevalences of 15%, 5.5%, and 1.5% (which are realistic for age groups 80 y, 65 y, and 40 y and older, respectively, only 30%, 12%, and 3% of the group classified as high risk are cases. Additionally, we present examples for four other diseases for which strongly associated variants have been discovered. In type 2 diabetes, our classification model of 12 SNPs has an AUC of only 0.64, and two SNPs achieve an AUC of only 0.56 for prostate cancer. Nine SNPs were not sufficient to improve the discrimination power over that of nongenetic predictors for risk of cardiovascular events. Finally, in Crohn's disease, a model of five SNPs, one with a quite low odds ratio of 0.26, has an AUC of only 0.66. Our analyses and examples show that strong association, although very valuable for establishing etiological hypotheses, does not guarantee effective discrimination between cases and controls. The scientific community should be cautious to avoid overstating the value of association findings in terms

The DNA Replication Stress Hypothesis of Alzheimer’s Disease

Directory of Open Access Journals (Sweden)

Yuri B. Yurov

2011-01-01

Full Text Available A well-recognized theory of Alzheimer’s disease (AD pathogenesis suggests ectopic cell cycle events to mediate neurodegeneration. Vulnerable neurons of the AD brain exhibit biomarkers of cell cycle progression and DNA replication suggesting a reentry into the cell cycle. Chromosome reduplication without proper cell cycle completion and mitotic division probably causes neuronal cell dysfunction and death. However, this theory seems to require some inputs in accordance with the generally recognized amyloid cascade theory as well as to explain causes and consequences of genomic instability (aneuploidy in the AD brain. We propose that unscheduled and incomplete DNA replication (replication stress destabilizes (epigenomic landscape in the brain and leads to DNA replication “catastrophe” causing cell death during the S phase (replicative cell death. DNA replication stress can be a key element of the pathogenetic cascade explaining the interplay between ectopic cell cycle events and genetic instabilities in the AD brain. Abnormal cell cycle reentry and somatic genome variations can be used for updating the cell cycle theory introducing replication stress as a missing link between cell genetics and neurobiology of AD.

Repair replication in replicating and nonreplicating DNA after irradiation with uv light

Energy Technology Data Exchange (ETDEWEB)

Slor, H.; Cleaver, J.E.

1978-06-01

Ultraviolet light induces more pyrimidine dimers and more repair replication in DNA that replicates within 2 to 3 h of irradiation than in DNA that does not replicate during this period. This difference may be due to special conformational changes in DNA and chromatin that might be associated with semiconservative DNA replication.

Replication of recently identified systemic lupus erythematosus genetic associations: a case-control study

Czech Academy of Sciences Publication Activity Database

Suarez-Gestal, M.; Calaza, M.; Endreffy, E.; Pullmann, R.; Ordi-Ros, J.; Sebastiani, D.G.; Růžičková, Šárka; Santos, J.M.; Papasteriades, C.; Marchini, M.; Skopouli, F.N.; Suarez, A.; Blanco, F.J.; D'Alfonso, S.; Bijl, M.; Carreira, P.; Witte, T.; Migliaresi, S.; Gomez-Reino, J.J.; Gonzalez, A.

2009-01-01

Roč. 11, č. 3 (2009), R69 ISSN 1478-6362 Keywords : Single nucleotide polymorphism susceptibility * sytemic lupus erythematosus Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.271, year: 2009

A Follow-up Association Study of Genetic Variants for Bone Mineral Density in a Korean Population

Directory of Open Access Journals (Sweden)

Seokjin Ham

2014-09-01

Full Text Available Bone mineral density (BMD is one of the quantitative traits that are genetically inherited and affected by various factors. Over the past years, genome-wide association studies (GWASs have searched for many genetic loci that influence BMD. A recent meta-analysis of 17 GWASs for BMD of the femoral neck and lumbar spine is the largest GWAS for BMD to date and offers 64 single-nucleotide polymorphisms (SNPs in 56 associated loci. We investigated these BMD loci in a Korean population called Korea Association REsource (KARE to identify their validity in an independent study. The KARE population contains genotypes from 8,842 individuals, and their BMD levels were measured at the distal radius (BMD-RT and midshaft tibia (BMD-TT. Thirteen genomic loci among 56 loci were significantly associated with BMD variations, and 3 loci were involved in known biological pathways related to BMD. In order to find putative functional variants, nearby SNPs in relation to linkage equilibrium were annotated, and their possible functional effects were predicted. These findings reveal that tens of variants, not a single factor, may contribute to the genetic architecture of BMD; have an important role regardless of ethnic group; and may highlight the importance of a replication study in GWASs to validate genuine loci for BMD variation.

Identification of Host Cell Factors Associated with Astrovirus Replication in Caco-2 Cells

OpenAIRE

Murillo, Andrea; Vera-Estrella, Rosario; Barkla, Bronwyn J.; Méndez, Ernesto; Arias, Carlos F.

2015-01-01

Astroviruses are small, nonenveloped viruses with a single-stranded positive-sense RNA genome causing acute gastroenteritis in children and immunocompromised patients. Since positive-sense RNA viruses have frequently been found to replicate in association with membranous structures, in this work we characterized the replication of the human astrovirus serotype 8 strain Yuc8 in Caco-2 cells, using density gradient centrifugation and free-flow zonal electrophoresis (FFZE) to fractionate cellula...

Evolution of complexity in RNA-like replicator systems

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Hogeweg Paulien

2008-03-01

Full Text Available Abstract Background The evolution of complexity is among the most important questions in biology. The evolution of complexity is often observed as the increase of genetic information or that of the organizational complexity of a system. It is well recognized that the formation of biological organization – be it of molecules or ecosystems – is ultimately instructed by the genetic information, whereas it is also true that the genetic information is functional only in the context of the organization. Therefore, to obtain a more complete picture of the evolution of complexity, we must study the evolution of both information and organization. Results Here we investigate the evolution of complexity in a simulated RNA-like replicator system. The simplicity of the system allows us to explicitly model the genotype-phenotype-interaction mapping of individual replicators, whereby we avoid preconceiving the functionality of genotypes (information or the ecological organization of replicators in the model. In particular, the model assumes that interactions among replicators – to replicate or to be replicated – depend on their secondary structures and base-pair matching. The results showed that a population of replicators, originally consisting of one genotype, evolves to form a complex ecosystem of up to four species. During this diversification, the species evolve through acquiring unique genotypes with distinct ecological functionality. The analysis of this diversification reveals that parasitic replicators, which have been thought to destabilize the replicator's diversity, actually promote the evolution of diversity through generating a novel "niche" for catalytic replicators. This also makes the current replicator system extremely stable upon the evolution of parasites. The results also show that the stability of the system crucially depends on the spatial pattern formation of replicators. Finally, the evolutionary dynamics is shown to

Hili Inhibits HIV Replication in Activated T Cells.

Science.gov (United States)

Peterlin, B Matija; Liu, Pingyang; Wang, Xiaoyun; Cary, Daniele; Shao, Wei; Leoz, Marie; Hong, Tian; Pan, Tao; Fujinaga, Koh

2017-06-01

P-element-induced wimpy-like (Piwil) proteins restrict the replication of mobile genetic elements in the germ line. They are also expressed in many transformed cell lines. In this study, we discovered that the human Piwil 2 (Hili) protein can also inhibit HIV replication, especially in activated CD4 + T cells that are the preferred target cells for this virus in the infected host. Although resting cells did not express Hili, its expression was rapidly induced following T cell activation. In these cells and transformed cell lines, depletion of Hili increased levels of viral proteins and new viral particles. Further studies revealed that Hili binds to tRNA. Some of the tRNAs represent rare tRNA species, whose codons are overrepresented in the viral genome. Targeting tRNA Arg (UCU) with an antisense oligonucleotide replicated effects of Hili and also inhibited HIV replication. Finally, Hili also inhibited the retrotransposition of the endogenous intracysternal A particle (IAP) by a similar mechanism. Thus, Hili joins a list of host proteins that inhibit the replication of HIV and other mobile genetic elements. IMPORTANCE Piwil proteins inhibit the movement of mobile genetic elements in the germ line. In their absence, sperm does not form and male mice are sterile. This inhibition is thought to occur via small Piwi-interacting RNAs (piRNAs). However, in some species and in human somatic cells, Piwil proteins bind primarily to tRNA. In this report, we demonstrate that human Piwil proteins, especially Hili, not only bind to select tRNA species, including rare tRNAs, but also inhibit HIV replication. Importantly, T cell activation induces the expression of Hili in CD4 + T cells. Since Hili also inhibited the movement of an endogenous retrovirus (IAP), our finding shed new light on this intracellular resistance to exogenous and endogenous retroviruses as well as other mobile genetic elements. Copyright © 2017 American Society for Microbiology.

Differential association with cellular substructures of pseudorabies virus DNA during early and late phases of replication

International Nuclear Information System (INIS)

Ben-Porat, T.; Veach, R.A.; Blankenship, M.L.; Kaplan, A.S.

1984-01-01

Pseudorabies virus DNA synthesis can be divided into two phases, early and late, which can be distinguished from each other on the basis of the structures of the replicating DNA. The two types of replicating virus DNA can also be distinguished from each other on the basis of the cellular substructures with which each is associated. Analysis by electron microscopic autoradiography showed that during the first round of replication, nascent virus DNA was found in the vicinity of the nuclear membrane; during later rounds of replication the nascent virus DNA was located centrally within the nucleus. The degree of association of virus DNA synthesized at early and late phases with the nuclear matrix fractions also differed; a larger proportion of late than of early nascent virus DNA was associated with this fraction. While nascent cellular DNA only was associated in significant amounts with the nuclear matrix fraction, a large part (up to 40%) of all the virus DNA remained associated with this fraction. However, no retention of specific virus proteins in this fraction was observed. Except for two virus proteins, which were preferentially extracted from the nuclear matrix, approximately 20% of all virus proteins remained in the nuclear matrix fraction. The large proportion of virus DNA associated with the nuclear fraction indicated that virus DNA may be intimately associated with some proteins

Genetic Determinants of Metabolism and Benign Prostate Enlargement: Associations with Prostate Volume.

Directory of Open Access Journals (Sweden)

Ayush Giri

Full Text Available Prostate enlargement leading to clinical benign prostatic hyperplasia (BPH is associated with metabolic dysregulation and obesity. The genetic basis of this association is unclear. Our objective was to evaluate whether single nucleotide polymorphisms (SNPs previously associated with metabolic disorders are also associated with prostate volume (PV. Participants included 876 men referred for prostate biopsy and found to be prostate cancer free. PV was measured by transrectal ultrasound. Samples were genotyped using the Illumina Cardio-MetaboChip platform. Multivariable adjusted linear regression models were used to evaluate SNPs (additive coding in relation to natural-log transformed (log PV. We compared SNP-PV results from biopsy-negative men to 442 men with low-grade prostate cancer with similar levels of obesity and PV. Beta-coefficients from the discovery and replication samples were then aggregated with fixed effects inverse variance weighted meta-analysis. SNP rs11736129 (near the pseudo-gene LOC100131429 was significantly associated with log-PV (beta: 0.16, p-value 1.16x10(-8 after adjusting for multiple testing. Other noteworthy SNPs that were nominally associated (p-value < 1x10(-4 with log-PV included rs9583484 (intronic SNP in COL4A2, rs10146527 (intronic SNP in NRXN3, rs9909466 (SNP near RPL32P31, and rs2241606 (synonymous SNP in SLC12A7. We found several SNPs in metabolic loci associated with PV. Further studies are needed to confirm our results and elucidate the mechanism between these genetic loci, PV, and clinical BPH.

Genetic Predisposition to Dyslipidemia and Risk of Preeclampsia.

Science.gov (United States)

Spracklen, Cassandra N; Saftlas, Audrey F; Triche, Elizabeth W; Bjonnes, Andrew; Keating, Brendan; Saxena, Richa; Breheny, Patrick J; Dewan, Andrew T; Robinson, Jennifer G; Hoh, Josephine; Ryckman, Kelli K

2015-07-01

Large epidemiologic studies support the role of dyslipidemia in preeclampsia; however, the etiology of preeclampsia or whether dyslipidemia plays a causal role remains unclear. We examined the association between the genetic predisposition to dyslipidemia and risk of preeclampsia using validated genetic markers of dyslipidemia. Preeclampsia cases (n = 164) and normotensive controls (n = 110) were selected from live birth certificates to nulliparous Iowa women during the period August 2002 to May 2005. Disease status was verified by medical chart review. Genetic predisposition to dyslipidemia was estimated by 4 genetic risk scores (GRS) (total cholesterol (TC), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), and triglycerides) on the basis of established loci for blood lipids. Logistic regression analyses were used to evaluate the relationships between each of the 4 genotype scores and preeclampsia. Replication analyses were performed in an independent, US population of preeclampsia cases (n = 516) and controls (n = 1,097) of European ancestry. The GRS related to higher levels of TC, LDL-C, and triglycerides demonstrated no association with the risk of preeclampsia in either the Iowa or replication population. The GRS related to lower HDL-C was marginally associated with an increased risk for preeclampsia (odds ratio (OR) = 1.03, 95% confidence interval (CI) = 0.99-1.07; P = 0.10). In the independent replication population, the association with the HDL-C GRS was also marginally significant (OR = 1.03, 95% CI: 1.00-1.06; P = 0.04). Our data suggest a potential effect between the genetic predisposition to dyslipidemic levels of HDL-C and an increased risk of preeclampsia, and, as such, suggest that dyslipidemia may be a component along the causal pathway to preeclampsia. © American Journal of Hypertension, Ltd 2014. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Dengue virus replicates and accumulates in Aedes aegypti salivary glands

Energy Technology Data Exchange (ETDEWEB)

Raquin, Vincent, E-mail: vincent.raquin@univ-lyon1.fr [Insect-Virus Interactions Group, Department of Genomes and Genetics, Institut Pasteur, 75015 Paris (France); Centre National de la Recherche Scientifique, Unité de Recherche Associée 3012, 75015 Paris (France); Lambrechts, Louis, E-mail: louis.lambrechts@pasteur.fr [Insect-Virus Interactions Group, Department of Genomes and Genetics, Institut Pasteur, 75015 Paris (France); Centre National de la Recherche Scientifique, Unité de Recherche Associée 3012, 75015 Paris (France)

2017-07-15

Dengue virus (DENV) is an RNA virus transmitted among humans by mosquito vectors, mainly Aedes aegypti. DENV transmission requires viral dissemination from the mosquito midgut to the salivary glands. During this process the virus undergoes several population bottlenecks, which are stochastic reductions in population size that restrict intra-host viral genetic diversity and limit the efficiency of natural selection. Despite the implications for virus transmission and evolution, DENV replication in salivary glands has not been directly demonstrated. Here, we used a strand-specific quantitative RT-PCR assay to demonstrate that negative-strand DENV RNA is produced in Ae. aegypti salivary glands, providing conclusive evidence that viral replication occurs in this tissue. Furthermore, we showed that the concentration of DENV genomic RNA in salivary glands increases significantly over time, indicating that active replication likely replenishes DENV genetic diversity prior to transmission. These findings improve our understanding of the biological determinants of DENV fitness and evolution. - Highlights: •Strand-specific RT-qPCR allows accurate quantification of DENV (-) RNA in mosquito tissues. •Detection of DENV (-) RNA in salivary glands provides evidence of viral replication in this tissue. •Viral replication in salivary glands likely replenishes DENV genetic diversity prior to transmission.

Dengue virus replicates and accumulates in Aedes aegypti salivary glands

International Nuclear Information System (INIS)

Raquin, Vincent; Lambrechts, Louis

2017-01-01

Dengue virus (DENV) is an RNA virus transmitted among humans by mosquito vectors, mainly Aedes aegypti. DENV transmission requires viral dissemination from the mosquito midgut to the salivary glands. During this process the virus undergoes several population bottlenecks, which are stochastic reductions in population size that restrict intra-host viral genetic diversity and limit the efficiency of natural selection. Despite the implications for virus transmission and evolution, DENV replication in salivary glands has not been directly demonstrated. Here, we used a strand-specific quantitative RT-PCR assay to demonstrate that negative-strand DENV RNA is produced in Ae. aegypti salivary glands, providing conclusive evidence that viral replication occurs in this tissue. Furthermore, we showed that the concentration of DENV genomic RNA in salivary glands increases significantly over time, indicating that active replication likely replenishes DENV genetic diversity prior to transmission. These findings improve our understanding of the biological determinants of DENV fitness and evolution. - Highlights: •Strand-specific RT-qPCR allows accurate quantification of DENV (-) RNA in mosquito tissues. •Detection of DENV (-) RNA in salivary glands provides evidence of viral replication in this tissue. •Viral replication in salivary glands likely replenishes DENV genetic diversity prior to transmission.

Recent advances in asthma genetics

Directory of Open Access Journals (Sweden)

Sandford Andrew J

2008-01-01

Full Text Available Abstract There are over 100 genes that have been reported to be associated with asthma or related phenotypes. In 2006–2007 alone there were 53 novel candidate gene associations reported in the literature. Replication of genetic associations and demonstration of a functional mechanism for the associated variants are needed to confirm an asthma susceptibility gene. For most of the candidate genes there is little functional information. In a previous review by Hoffjan et al. published in 2003, functional information was reported for 40 polymorphisms and here we list another 22 genes which have such data. Some important genes such as filaggrin, interleukin-13, interleukin-17 and the cysteinyl leukotriene receptor-1 which not only were replicated by independent association studies but also have functional data are reviewed in this article.

Assessment of heterogeneity between European Populations: a Baltic and Danish replication case-control study of SNPs from a recent European ulcerative colitis genome wide association study

Directory of Open Access Journals (Sweden)

Jonaitis Laimas

2011-10-01

Full Text Available Abstract Background Differences in the genetic architecture of inflammatory bowel disease between different European countries and ethnicities have previously been reported. In the present study, we wanted to assess the role of 11 newly identified UC risk variants, derived from a recent European UC genome wide association study (GWAS (Franke et al., 2010, for 1 association with UC in the Nordic countries, 2 for population heterogeneity between the Nordic countries and the rest of Europe, and, 3 eventually, to drive some of the previous findings towards overall genome-wide significance. Methods Eleven SNPs were replicated in a Danish sample consisting of 560 UC patients and 796 controls and nine missing SNPs of the German GWAS study were successfully genotyped in the Baltic sample comprising 441 UC cases and 1156 controls. The independent replication data was then jointly analysed with the original data and systematic comparisons of the findings between ethnicities were made. Pearson's χ2, Breslow-Day (BD and Cochran-Mantel-Haenszel (CMH tests were used for association analyses and heterogeneity testing. Results The rs5771069 (IL17REL SNP was not associated with UC in the Danish panel. The rs5771069 (IL17REL SNP was significantly associated with UC in the combined Baltic, Danish and Norwegian UC study sample driven by the Norwegian panel (OR = 0.89, 95% CI: 0.79-0.98, P = 0.02. No association was found between rs7809799 (SMURF1/KPNA7 and UC (OR = 1.20, 95% CI: 0.95-1.52, P = 0.10 or between UC and all other remaining SNPs. We had 94% chance of detecting an association for rs7809799 (SMURF1/KPNA7 in the combined replication sample, whereas the power were 55% or lower for the remaining SNPs. Statistically significant PBD was found for OR heterogeneity between the combined Baltic, Danish, and Norwegian panel versus the combined German, British, Belgian, and Greek panel (rs7520292 (P = 0.001, rs12518307 (P = 0.007, and rs2395609 (TCP11 (P = 0

Investigation of genetic variation in scavenger receptor class B, member 1 (SCARB1) and association with serum carotenoids

Science.gov (United States)

McKay, Gareth J; Loane, Edward; Nolan, John M; Patterson, Christopher C; Meyers, Kristin J; Mares, Julie A; Yonova-Doing, Ekaterina; Hammond, Christopher J; Beatty, Stephen; Silvestri, Giuliana

2013-01-01

Objective To investigate association of scavenger receptor class B, member 1 (SCARB1) genetic variants with serum carotenoid levels of lutein (L) and zeaxanthin (Z) and macular pigment optical density (MPOD). Design A cross-sectional study of healthy adults aged 20-70. Participants 302 participants recruited following local advertisement. Methods MPOD was measured by customized heterochromatic flicker photometry. Fasting blood samples were taken for serum L and Z measurement by HPLC and lipoprotein analysis by spectrophotometric assay. Forty-seven single nucleotide polymorphisms (SNPs) across SCARB1 were genotyped using Sequenom technology. Association analyses were performed using PLINK to compare allele and haplotype means, with adjustment for potential confounding and correction for multiple comparisons by permutation testing. Replication analysis was performed in the TwinsUK and CAREDS cohorts. Main outcome measures Odds ratios (ORs) for macular pigment optical density area, serum lutein and zeaxanthin concentrations associated with genetic variations in SCARB1 and interactions between SCARB1 and sex. Results Following multiple regression analysis with adjustment for age, body mass index, sex, high-density lipoprotein cholesterol (HDLc), low-density lipoprotein cholesterol (LDLc), triglycerides, smoking, dietary L and Z levels, 5 SNPs were significantly associated with serum L concentration and 1 SNP with MPOD (P<0.01). Only the association between rs11057841 and serum L withstood correction for multiple comparisons by permutation testing (P<0.01) and replicated in the TwinsUK cohort (P=0.014). Independent replication was also observed in the CAREDS cohort with rs10846744 (P=2×10−4), a SNP in high linkage disequilibrium with rs11057841 (r2=0.93). No significant interactions by sex were found. Haplotype analysis revealed no stronger association than obtained with single SNP analyses. Conclusions Our study has identified association between rs11057841 and

DNA replication origins—where do we begin?

Science.gov (United States)

Prioleau, Marie-Noëlle; MacAlpine, David M.

2016-01-01

For more than three decades, investigators have sought to identify the precise locations where DNA replication initiates in mammalian genomes. The development of molecular and biochemical approaches to identify start sites of DNA replication (origins) based on the presence of defining and characteristic replication intermediates at specific loci led to the identification of only a handful of mammalian replication origins. The limited number of identified origins prevented a comprehensive and exhaustive search for conserved genomic features that were capable of specifying origins of DNA replication. More recently, the adaptation of origin-mapping assays to genome-wide approaches has led to the identification of tens of thousands of replication origins throughout mammalian genomes, providing an unprecedented opportunity to identify both genetic and epigenetic features that define and regulate their distribution and utilization. Here we summarize recent advances in our understanding of how primary sequence, chromatin environment, and nuclear architecture contribute to the dynamic selection and activation of replication origins across diverse cell types and developmental stages. PMID:27542827

Phenome Wide Association Studies demonstrating pleiotropy of genetic variants within FTO with and without adjustment for body mass index

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Robert Michael Cronin

2014-08-01

Full Text Available Phenome-wide association studies (PheWAS have demonstrated utility in validating genetic associations derived from traditional genetic studies as well as identifying novel genetic associations. Here we used an electronic health record (EHR-based PheWAS to explore pleiotropy of genetic variants in the fat mass and obesity associated gene (FTO, some of which have been previously associated with obesity and type 2 diabetes (T2D. We used a population of 10,487 individuals of European ancestry with genome-wide genotyping from the Electronic Medical Records and Genomics (eMERGE Network and another population of 13,711 individuals of European ancestry from the BioVU DNA biobank at Vanderbilt genotyped using Illumina HumanExome BeadChip. A meta-analysis of the two study populations replicated the well-described associations between FTO variants and obesity (odds ratio [OR]=1.25, 95% Confidence Interval=1.11-1.24, p=2.10 x 10 9 and FTO variants and T2D (OR=1.14, 95% CI=1.08-1.21, p=2.34 x 10 6. The meta-analysis also demonstrated that FTO variant rs8050136 was significantly associated with sleep apnea (OR=1.14, 95% CI=1.07-1.22, p=3.33 x 10 5; however, the association was attenuated after adjustment for body mass index (BMI. Novel phenotype associations with obesity-associated FTO variants included fibrocystic breast disease (rs9941349, OR=0.81, 95% CI=0.74-0.91, p=5.41x10 5 and trends toward associations with nonalcoholic liver disease and gram-positive bacterial infections. FTO variants not associated with obesity demonstrated other potential disease associations including noninflammatory disorders of the cervix and chronic periodontitis. These results suggest that genetic variants in FTO may have pleiotropic associations, some of which are not mediated by obesity.

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

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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.

Genetics

International Nuclear Information System (INIS)

Hubitschek, H.E.

1975-01-01

Progress is reported on the following research projects: genetic effects of high LET radiations; genetic regulation, alteration, and repair; chromosome replication and the division cycle of Escherichia coli; effects of radioisotope decay in the DNA of microorganisms; initiation and termination of DNA replication in Bacillus subtilis; mutagenesis in mouse myeloma cells; lethal and mutagenic effects of near-uv radiation; effect of 8-methoxypsoralen on photodynamic lethality and mutagenicity in Escherichia coli; DNA repair of the lethal effects of far-uv; and near uv irradiation of bacterial cells

Association of Genetic Variants Related to Serum Calcium Levels With Coronary Artery Disease and Myocardial Infarction.

Science.gov (United States)

Larsson, Susanna C; Burgess, Stephen; Michaëlsson, Karl

2017-07-25

Serum calcium has been associated with cardiovascular disease in observational studies and evidence from randomized clinical trials indicates that calcium supplementation, which raises serum calcium levels, may increase the risk of cardiovascular events, particularly myocardial infarction. To evaluate the potential causal association between genetic variants related to elevated serum calcium levels and risk of coronary artery disease (CAD) and myocardial infarction using mendelian randomization. The analyses were performed using summary statistics obtained for single-nucleotide polymorphisms (SNPs) identified from a genome-wide association meta-analysis of serum calcium levels (N = up to 61 079 individuals) and from the Coronary Artery Disease Genome-wide Replication and Meta-analysis Plus the Coronary Artery Disease Genetics (CardiogramplusC4D) consortium's 1000 genomes-based genome-wide association meta-analysis (N = up to 184 305 individuals) that included cases (individuals with CAD and myocardial infarction) and noncases, with baseline data collected from 1948 and populations derived from across the globe. The association of each SNP with CAD and myocardial infarction was weighted by its association with serum calcium, and estimates were combined using an inverse-variance weighted meta-analysis. Genetic risk score based on genetic variants related to elevated serum calcium levels. Co-primary outcomes were the odds of CAD and myocardial infarction. Among the mendelian randomized analytic sample of 184 305 individuals (60 801 CAD cases [approximately 70% with myocardial infarction] and 123 504 noncases), the 6 SNPs related to serum calcium levels and without pleiotropic associations with potential confounders were estimated to explain about 0.8% of the variation in serum calcium levels. In the inverse-variance weighted meta-analysis (combining the estimates of the 6 SNPs), the odds ratios per 0.5-mg/dL increase (about 1 SD) in genetically

An ADAM33 polymorphism associates with progression of preschool wheeze into childhood asthma: a prospective case-control study with replication in a birth cohort study.

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Ester M M Klaassen

Full Text Available The influence of asthma candidate genes on the development from wheeze to asthma in young children still needs to be defined.To link genetic variants in asthma candidate genes to progression of wheeze to persistent wheeze into childhood asthma.In a prospective study, children with recurrent wheeze from the ADEM (Asthma DEtection and Monitoring study were followed until the age of six. At that age a classification (transient wheeze or asthma was based on symptoms, lung function and medication use. In 198 children the relationship between this classification and 30 polymorphisms in 16 asthma candidate genes was assessed by logistic regression. In case of an association based on a p<0.10, replication analysis was performed in an independent birth cohort study (KOALA study, n = 248 included for the present analysis.In the ADEM study, the minor alleles of ADAM33 rs511898 and rs528557 and the ORMDL3/GSDMB rs7216389 polymorphisms were negatively associated, whereas the minor alleles of IL4 rs2243250 and rs2070874 polymorphisms were positively associated with childhood asthma. When replicated in the KOALA study, ADAM33 rs528557 showed a negative association of the CG/GG-genotype with progression of recurrent wheeze into childhood asthma (0.50 (0.26-0.97 p = 0.04 and no association with preschool wheeze.Polymorphisms in ADAM33, ORMDL3/GSDMB and IL4 were associated with childhood asthma in a group of children with recurrent wheeze. The replication of the negative association of the CG/GG-genotype of rs528557 ADAM33 with childhood asthma in an independent birth cohort study confirms that a compromised ADAM33 gene may be implicated in the progression of wheeze into childhood asthma.

The expanding universe of inflammatory bowel disease genetics.

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Achkar, Jean-Paul; Duerr, Richard

2008-07-01

Genetic factors play an important role in the pathogenesis of inflammatory bowel disease. In this review, we will provide an update on the rapid advances in the discovery of inflammatory bowel disease, primarily Crohn's disease, associated genes. Seven recently published Crohn's disease genome-wide association studies have confirmed prior findings related to the nucleotide-binding oligomerization domain 2 (NOD2) gene and the IBD5 locus. In addition, 10 novel loci have been identified and well replicated. Several promising associations between Crohn's disease and gene variants have been identified and replicated, the two most widely replicated being variants in the IL23R and ATG16L1 genes. These findings highlight and further support the importance of the immune system and its interactions with the intestinal microflora in the pathogenesis of inflammatory bowel disease.

Molecular Mechanisms of DNA Replication Checkpoint Activation

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Bénédicte Recolin

2014-03-01

Full Text Available The major challenge of the cell cycle is to deliver an intact, and fully duplicated, genetic material to the daughter cells. To this end, progression of DNA synthesis is monitored by a feedback mechanism known as replication checkpoint that is untimely linked to DNA replication. This signaling pathway ensures coordination of DNA synthesis with cell cycle progression. Failure to activate this checkpoint in response to perturbation of DNA synthesis (replication stress results in forced cell division leading to chromosome fragmentation, aneuploidy, and genomic instability. In this review, we will describe current knowledge of the molecular determinants of the DNA replication checkpoint in eukaryotic cells and discuss a model of activation of this signaling pathway crucial for maintenance of genomic stability.

Genetic Associations with Gestational Duration and Spontaneous Preterm Birth

DEFF Research Database (Denmark)

Zhang, G.; Feenstra, B.; Bacelis, J.

2017-01-01

. METHODS: We performed a genomewide association study in a discovery set of samples obtained from 43,568 women of European ancestry using gestational duration as a continuous trait and term or preterm (... of 8643 women) to test for replication of genomic loci that had significant genomewide association (Pdiscovery set. RESULTS: In the discovery and replication data sets, four loci (EBF1, EEFSEC, AGTR2, and WNT4) were...... significantly associated with gestational duration. Functional analysis showed that an implicated variant in WNT4 alters the binding of the estrogen receptor. The association between variants in ADCY5 and RAP2C and gestational duration had suggestive significance in the discovery set and significant evidence...

DNA replication origins-where do we begin?

Science.gov (United States)

Prioleau, Marie-Noëlle; MacAlpine, David M

2016-08-01

For more than three decades, investigators have sought to identify the precise locations where DNA replication initiates in mammalian genomes. The development of molecular and biochemical approaches to identify start sites of DNA replication (origins) based on the presence of defining and characteristic replication intermediates at specific loci led to the identification of only a handful of mammalian replication origins. The limited number of identified origins prevented a comprehensive and exhaustive search for conserved genomic features that were capable of specifying origins of DNA replication. More recently, the adaptation of origin-mapping assays to genome-wide approaches has led to the identification of tens of thousands of replication origins throughout mammalian genomes, providing an unprecedented opportunity to identify both genetic and epigenetic features that define and regulate their distribution and utilization. Here we summarize recent advances in our understanding of how primary sequence, chromatin environment, and nuclear architecture contribute to the dynamic selection and activation of replication origins across diverse cell types and developmental stages. © 2016 Prioleau and MacAlpine; Published by Cold Spring Harbor Laboratory Press.

Chronic Stress and Neuropathology: Neurochemical, Molecular, and Genetic Factors

National Research Council Canada - National Science Library

Koob, George F; Zorrilla, Eric P

2005-01-01

... to selective breeding in the rat. Genetic differences in stress responsiveness in replicate line 1 were associated with differences in anxiety-like behavior, body weight gain and voluntary intake of sweet solutions and ethanol...

The use of genome-wide eQTL associations in lymphoblastoid cell lines to identify novel genetic pathways involved in complex traits.

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Josine L Min

Full Text Available The integrated analysis of genotypic and expression data for association with complex traits could identify novel genetic pathways involved in complex traits. We profiled 19,573 expression probes in Epstein-Barr virus-transformed lymphoblastoid cell lines (LCLs from 299 twins and correlated these with 44 quantitative traits (QTs. For 939 expressed probes correlating with more than one QT, we investigated the presence of eQTL associations in three datasets of 57 CEU HapMap founders and 86 unrelated twins. Genome-wide association analysis of these probes with 2.2 m SNPs revealed 131 potential eQTLs (1,989 eQTL SNPs overlapping between the HapMap datasets, five of which were in cis (58 eQTL SNPs. We then tested 535 SNPs tagging the eQTL SNPs, for association with the relevant QT in 2,905 twins. We identified nine potential SNP-QT associations (P<0.01 but none significantly replicated in five large consortia of 1,097-16,129 subjects. We also failed to replicate previous reported eQTL associations with body mass index, plasma low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides levels derived from lymphocytes, adipose and liver tissue. Our results and additional power calculations suggest that proponents may have been overoptimistic in the power of LCLs in eQTL approaches to elucidate regulatory genetic effects on complex traits using the small datasets generated to date. Nevertheless, larger tissue-specific expression data sets relevant to specific traits are becoming available, and should enable the adoption of similar integrated analyses in the near future.

Genetic influences on hand osteoarthritis in Finnish women--a replication study of candidate genes.

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Satu Hämäläinen

Full Text Available OBJECTIVES: Our aims were to replicate some previously reported associations of single nucleotide polymorphisms (SNPs in five genes (A2BP1, COG5, GDF5, HFE, ESR1 with hand osteoarthritis (OA, and to examine whether genes (BCAP29, DIO2, DUS4L, DVWA, HLA, PTGS2, PARD3B, TGFB1 and TRIB1 associated with OA at other joint sites were associated with hand OA among Finnish women. DESIGN: We examined the bilateral hand radiographs of 542 occupationally active Finnish female dentists and teachers aged 45 to 63 and classified them according to the presence of OA by using reference images. Data regarding finger joint pain and other risk factors were collected using a questionnaire. We defined two hand OA phenotypes: radiographic OA in at least three joints (ROA and symptomatic DIP OA. The genotypes were determined by PCR-based methods. In statistical analysis, we used SNPStats software, the chi-square test and logistic regression. RESULTS: Of the SNPs, rs716508 in A2BP1 was associated with ROA (OR = 0.7, 95% CI 0.5-0.9 and rs1800470 in TGFB1 with symptomatic DIP OA (1.8, 1.2-2.9. We found an interaction between ESR1 (rs9340799 and occupation: teachers with the minor allele were at an increased risk of symptomatic DIP OA (2.8, 1.3-6.5. We saw no association among the dentists. We also found that the carriage of the COG5 rs3757713 C allele increased the risk of ROA only among women with the BCAP29 rs10953541 CC genotype (2.6; 1.1-6.1. There was also a suggestive interaction between the HFE rs179945 and the ESR1 rs9340799, and the carriage of the minor allele of either of these SNPs was associated with an increased risk of symptomatic DIP OA (2.1, 1.3-2.5. CONCLUSIONS: Our results support the earlier findings of A2BP1 and TBGF1 being OA susceptibility genes and provide evidence of a possible gene-gene interaction in the genetic influence on hand OA predisposition.

Evolution of Replication Machines

Science.gov (United States)

Yao, Nina Y.; O'Donnell, Mike E.

2016-01-01

The machines that decode and regulate genetic information require the translation, transcription and replication pathways essential to all living cells. Thus, it might be expected that all cells share the same basic machinery for these pathways that were inherited from the primordial ancestor cell from which they evolved. A clear example of this is found in the translation machinery that converts RNA sequence to protein. The translation process requires numerous structural and catalytic RNAs and proteins, the central factors of which are homologous in all three domains of life, bacteria, archaea and eukarya. Likewise, the central actor in transcription, RNA polymerase, shows homology among the catalytic subunits in bacteria, archaea and eukarya. In contrast, while some “gears” of the genome replication machinery are homologous in all domains of life, most components of the replication machine appear to be unrelated between bacteria and those of archaea and eukarya. This review will compare and contrast the central proteins of the “replisome” machines that duplicate DNA in bacteria, archaea and eukarya, with an eye to understanding the issues surrounding the evolution of the DNA replication apparatus. PMID:27160337

Genome-wide association study identifies 74 loci associated with educational attainment

Science.gov (United States)

Okbay, Aysu; Beauchamp, Jonathan P.; Fontana, Mark A.; Lee, James J.; Pers, Tune H.; Rietveld, Cornelius A.; Turley, Patrick; Chen, Guo-Bo; Emilsson, Valur; Meddens, S. Fleur W.; Oskarsson, Sven; Pickrell, Joseph K.; Thom, Kevin; Timshel, Pascal; de Vlaming, Ronald; Abdellaoui, Abdel; Ahluwalia, Tarunveer S.; Bacelis, Jonas; Baumbach, Clemens; Bjornsdottir, Gyda; Brandsma, Johannes H.; Concas, Maria Pina; Derringer, Jaime; Furlotte, Nicholas A.; Galesloot, Tessel E.; Girotto, Giorgia; Gupta, Richa; Hall, Leanne M.; Harris, Sarah E.; Hofer, Edith; Horikoshi, Momoko; Huffman, Jennifer E.; Kaasik, Kadri; Kalafati, Ioanna P.; Karlsson, Robert; Kong, Augustine; Lahti, Jari; van der Lee, Sven J.; de Leeuw, Christiaan; Lind, Penelope A.; Lindgren, Karl-Oskar; Liu, Tian; Mangino, Massimo; Marten, Jonathan; Mihailov, Evelin; Miller, Michael B.; van der Most, Peter J.; Oldmeadow, Christopher; Payton, Antony; Pervjakova, Natalia; Peyrot, Wouter J.; Qian, Yong; Raitakari, Olli; Rueedi, Rico; Salvi, Erika; Schmidt, Börge; Schraut, Katharina E.; Shi, Jianxin; Smith, Albert V.; Poot, Raymond A.; Pourcain, Beate; Teumer, Alexander; Thorleifsson, Gudmar; Verweij, Niek; Vuckovic, Dragana; Wellmann, Juergen; Westra, Harm-Jan; Yang, Jingyun; Zhao, Wei; Zhu, Zhihong; Alizadeh, Behrooz Z.; Amin, Najaf; Bakshi, Andrew; Baumeister, Sebastian E.; Biino, Ginevra; Bønnelykke, Klaus; Boyle, Patricia A.; Campbell, Harry; Cappuccio, Francesco P.; Davies, Gail; De Neve, Jan-Emmanuel; Deloukas, Panos; Demuth, Ilja; Ding, Jun; Eibich, Peter; Eisele, Lewin; Eklund, Niina; Evans68, David M.; Faul, Jessica D.; Feitosa, Mary F.; Forstner, Andreas J.; Gandin, Ilaria; Gunnarsson, Bjarni; Halldórsson, Bjarni V.; Harris, Tamara B.; Heath, Andrew C.; Hocking, Lynne J.; Holliday, Elizabeth G.; Homuth, Georg; Horan, Michael A.; Hottenga, Jouke-Jan; de Jager, Philip L.; Joshi, Peter K.; Jugessur, Astanand; Kaakinen, Marika A.; Kähönen, Mika; Kanoni, Stavroula; Keltigangas-Järvinen, Liisa; Kiemeney, Lambertus A.L.M.; Kolcic, Ivana; Koskinen, Seppo; Kraja, Aldi T.; Kroh, Martin; Kutalik, Zoltan; Latvala, Antti; Launer, Lenore J.; Lebreton, Maël P.; Levinson, Douglas F.; Lichtenstein, Paul; Lichtner, Peter; Liewald, David C.M.; Loukola, Anu; Madden, Pamela A.; Mägi, Reedik; Mäki-Opas, Tomi; Marioni, Riccardo E.; Marques-Vidal, Pedro; Meddens, Gerardus A.; McMahon, George; Meisinger, Christa; Meitinger, Thomas; Milaneschi, Yusplitri; Milani, Lili; Montgomery, Grant W.; Myhre, Ronny; Nelson, Christopher P.; Nyholt, Dale R.; Ollier, William E.R.; Palotie, Aarno; Paternoster, Lavinia; Pedersen, Nancy L.; Petrovic, Katja E.; Porteous, David J.; Räikkönen, Katri; Ring, Susan M.; Robino, Antonietta; Rostapshova, Olga; Rudan, Igor; Rustichini, Aldo; Salomaa, Veikko; Sanders, Alan R.; Sarin, Antti-Pekka; Schmidt, Helena; Scott, Rodney J.; Smith, Blair H.; Smith, Jennifer A.; Staessen, Jan A.; Steinhagen-Thiessen, Elisabeth; Strauch, Konstantin; Terracciano, Antonio; Tobin, Martin D.; Ulivi, Sheila; Vaccargiu, Simona; Quaye, Lydia; van Rooij, Frank J.A.; Venturini, Cristina; Vinkhuyzen, Anna A.E.; Völker, Uwe; Völzke, Henry; Vonk, Judith M.; Vozzi, Diego; Waage, Johannes; Ware, Erin B.; Willemsen, Gonneke; Attia, John R.; Bennett, David A.; Berger, Klaus; Bertram, Lars; Bisgaard, Hans; Boomsma, Dorret I.; Borecki, Ingrid B.; Bultmann, Ute; Chabris, Christopher F.; Cucca, Francesco; Cusi, Daniele; Deary, Ian J.; Dedoussis, George V.; van Duijn, Cornelia M.; Eriksson, Johan G.; Franke, Barbara; Franke, Lude; Gasparini, Paolo; Gejman, Pablo V.; Gieger, Christian; Grabe, Hans-Jörgen; Gratten, Jacob; Groenen, Patrick J.F.; Gudnason, Vilmundur; van der Harst, Pim; Hayward, Caroline; Hinds, David A.; Hoffmann, Wolfgang; Hyppönen, Elina; Iacono, William G.; Jacobsson, Bo; Järvelin, Marjo-Riitta; Jöckel, Karl-Heinz; Kaprio, Jaakko; Kardia, Sharon L.R.; Lehtimäki, Terho; Lehrer, Steven F.; Magnusson, Patrik K.E.; Martin, Nicholas G.; McGue, Matt; Metspalu, Andres; Pendleton, Neil; Penninx, Brenda W.J.H.; Perola, Markus; Pirastu, Nicola; Pirastu, Mario; Polasek, Ozren; Posthuma, Danielle; Power, Christine; Province, Michael A.; Samani, Nilesh J.; Schlessinger, David; Schmidt, Reinhold; Sørensen, Thorkild I.A.; Spector, Tim D.; Stefansson, Kari; Thorsteinsdottir, Unnur; Thurik, A. Roy; Timpson, Nicholas J.; Tiemeier, Henning; Tung, Joyce Y.; Uitterlinden, André G.; Vitart, Veronique; Vollenweider, Peter; Weir, David R.; Wilson, James F.; Wright, Alan F.; Conley, Dalton C.; Krueger, Robert F.; Smith, George Davey; Hofman, Albert; Laibson, David I.; Medland, Sarah E.; Meyer, Michelle N.; Yang, Jian; Johannesson, Magnus; Visscher, Peter M.; Esko, Tõnu; Koellinger, Philipp D.; Cesarini, David; Benjamin, Daniel J.

2016-01-01

Summary Educational attainment (EA) is strongly influenced by social and other environmental factors, but genetic factors are also estimated to account for at least 20% of the variation across individuals1. We report the results of a genome-wide association study (GWAS) for EA that extends our earlier discovery sample1,2 of 101,069 individuals to 293,723 individuals, and a replication in an independent sample of 111,349 individuals from the UK Biobank. We now identify 74 genome-wide significant loci associated with number of years of schooling completed. Single-nucleotide polymorphisms (SNPs) associated with educational attainment are disproportionately found in genomic regions regulating gene expression in the fetal brain. Candidate genes are preferentially expressed in neural tissue, especially during the prenatal period, and enriched for biological pathways involved in neural development. Our findings demonstrate that, even for a behavioral phenotype that is mostly environmentally determined, a well-powered GWAS identifies replicable associated genetic variants that suggest biologically relevant pathways. Because EA is measured in large numbers of individuals, it will continue to be useful as a proxy phenotype in efforts to characterize the genetic influences of related phenotypes, including cognition and neuropsychiatric disease. PMID:27225129

Phenotypic and genetic associations between the big five and trait emotional intelligence.

Science.gov (United States)

Vernon, Philip A; Villani, Vanessa C; Schermer, Julie Aitken; Petrides, K V

2008-10-01

This study reports the first behavioral genetic investigation of the extent to which genetic and/or environmental factors contribute to the relationship between the Big Five personality factors and trait emotional intelligence. 213 pairs of adult monozygotic twins and 103 pairs of same-sex dizygotic twins completed the NEO-PI-R and the Trait Emotional Intelligence Questionnaire (TEIQue). Replicating previous non-twin studies, many significant phenotypic correlations were found between the Big Five factors - especially Neuroticism, Extraversion, and Conscientiousness - and the facets, factors, and global scores derived from the TEIQue. Bivariate behavioral genetic model-fitting analyses revealed that these phenotypic correlations were primarily attributable to correlated genetic factors and secondarily to correlated non-shared environmental factors. The results support the feasibility of incorporating EI as a trait within existing personality taxonomies.

Identification and replication of the interplay of four genetic high-risk variants for urinary bladder cancer.

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Selinski, Silvia; Blaszkewicz, Meinolf; Ickstadt, Katja; Gerullis, Holger; Otto, Thomas; Roth, Emanuel; Volkert, Frank; Ovsiannikov, Daniel; Moormann, Oliver; Banfi, Gergely; Nyirady, Peter; Vermeulen, Sita H; Garcia-Closas, Montserrat; Figueroa, Jonine D; Johnson, Alison; Karagas, Margaret R; Kogevinas, Manolis; Malats, Nuria; Schwenn, Molly; Silverman, Debra T; Koutros, Stella; Rothman, Nathaniel; Kiemeney, Lambertus A; Hengstler, Jan G; Golka, Klaus

2017-12-07

Little is known whether genetic variants identified in genome-wide association studies interact to increase bladder cancer risk. Recently, we identified two- and three-variant combinations associated with a particular increase of bladder cancer risk in a urinary bladder cancer case-control series (Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund (IfADo), 1501 cases, 1565 controls). In an independent case-control series (Nijmegen Bladder Cancer Study, NBCS, 1468 cases, 1720 controls) we confirmed these two- and three-variant combinations. Pooled analysis of the two studies as discovery group (IfADo-NBCS) resulted in sufficient statistical power to test up to four-variant combinations by a logistic regression approach. The New England and Spanish Bladder Cancer Studies (2080 cases and 2167 controls) were used as a replication series. Twelve previously identified risk variants were considered. The strongest four-variant combination was obtained in never smokers. The combination of rs1014971[AA] near apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3A (APOBEC3A) and chromobox homolog 6 (CBX6), solute carrier family 1s4 (urea transporter), member 1 (Kidd blood group) (SLC14A1) exon single nucleotide polymorphism (SNP) rs1058396[AG, GG], UDP glucuronosyltransferase 1 family, polypeptide A complex locus (UGT1A) intron SNP rs11892031[AA] and rs8102137[CC, CT] near cyclin E1 (CCNE1) resulted in an unadjusted odds ratio (OR) of 2.59 (95% CI = 1.93-3.47; P = 1.87 × 10-10), while the individual variant ORs ranged only between 1.11 and 1.30. The combination replicated in the New England and Spanish Bladder Cancer Studies (ORunadjusted = 1.60, 95% CI = 1.10-2.33; P = 0.013). The four-variant combination is relatively frequent, with 25% in never smoking cases and 11% in never smoking controls (total study group: 19% cases, 14% controls). In conclusion, we show that four high-risk variants can statistically interact to confer

Genetic association between human chitinases and lung function in COPD.

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Aminuddin, F; Akhabir, L; Stefanowicz, D; Paré, P D; Connett, J E; Anthonisen, N R; Fahy, J V; Seibold, M A; Burchard, E G; Eng, C; Gulsvik, A; Bakke, P; Cho, M H; Litonjua, A; Lomas, D A; Anderson, W H; Beaty, T H; Crapo, J D; Silverman, E K; Sandford, A J

2012-07-01

Two primary chitinases have been identified in humans--acid mammalian chitinase (AMCase) and chitotriosidase (CHIT1). Mammalian chitinases have been observed to affect the host's immune response. The aim of this study was to test for association between genetic variation in the chitinases and phenotypes related to chronic obstructive pulmonary disease (COPD). Polymorphisms in the chitinase genes were selected based on previous associations with respiratory diseases. Polymorphisms that were associated with lung function level or rate of decline in the Lung Health Study (LHS) cohort were analyzed for association with COPD affection status in four other COPD case-control populations. Chitinase activity and protein levels were also related to genotypes. In the caucasian LHS population, the baseline forced expiratory volume in one second (FEV(1)) was significantly different between the AA and GG genotypic groups of the AMCase rs3818822 polymorphism. Subjects with the GG genotype had higher AMCase protein and chitinase activity compared with AA homozygotes. For CHIT1 rs2494303, a significant association was observed between rate of decline in FEV(1) and the different genotypes. In the African American LHS population, CHIT1 rs2494303 and AMCase G339T genotypes were associated with rate of decline in FEV(1). Although a significant effect of chitinase gene alleles was found on lung function level and decline in the LHS, we were unable to replicate the associations with COPD affection status in the other COPD study groups.

An ADAM33 polymorphism associates with progression of preschool wheeze into childhood asthma: a prospective case-control study with replication in a birth cohort study.

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Klaassen, Ester M M; Penders, John; Jöbsis, Quirijn; van de Kant, Kim D G; Thijs, Carel; Mommers, Monique; van Schayck, Constant P; van Eys, Guillaume; Koppelman, Gerard H; Dompeling, Edward

2015-01-01

The influence of asthma candidate genes on the development from wheeze to asthma in young children still needs to be defined. To link genetic variants in asthma candidate genes to progression of wheeze to persistent wheeze into childhood asthma. In a prospective study, children with recurrent wheeze from the ADEM (Asthma DEtection and Monitoring) study were followed until the age of six. At that age a classification (transient wheeze or asthma) was based on symptoms, lung function and medication use. In 198 children the relationship between this classification and 30 polymorphisms in 16 asthma candidate genes was assessed by logistic regression. In case of an association based on a pchildhood asthma. When replicated in the KOALA study, ADAM33 rs528557 showed a negative association of the CG/GG-genotype with progression of recurrent wheeze into childhood asthma (0.50 (0.26-0.97) p = 0.04) and no association with preschool wheeze. Polymorphisms in ADAM33, ORMDL3/GSDMB and IL4 were associated with childhood asthma in a group of children with recurrent wheeze. The replication of the negative association of the CG/GG-genotype of rs528557 ADAM33 with childhood asthma in an independent birth cohort study confirms that a compromised ADAM33 gene may be implicated in the progression of wheeze into childhood asthma.

A possible genetic association with chronic fatigue in primary Sjögren's syndrome: a candidate gene study.

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Norheim, Katrine Brække; Le Hellard, Stephanie; Nordmark, Gunnel; Harboe, Erna; Gøransson, Lasse; Brun, Johan G; Wahren-Herlenius, Marie; Jonsson, Roland; Omdal, Roald

2014-02-01

Fatigue is prevalent and disabling in primary Sjögren's syndrome (pSS). Results from studies in chronic fatigue syndrome (CFS) indicate that genetic variation may influence fatigue. The aim of this study was to investigate single nucleotide polymorphism (SNP) variations in pSS patients with high and low fatigue. A panel of 85 SNPs in 12 genes was selected based on previous studies in CFS. A total of 207 pSS patients and 376 healthy controls were genotyped. One-hundred and ninety-three patients and 70 SNPs in 11 genes were available for analysis after quality control. Patients were dichotomized based on fatigue visual analogue scale (VAS) scores, with VAS fatigue" (n = 53) and VAS ≥50 denominated "high fatigue" (n = 140). We detected signals of association with pSS for one SNP in SLC25A40 (unadjusted p = 0.007) and two SNPs in PKN1 (both p = 0.03) in our pSS case versus control analysis. The association with SLC25A40 was stronger when only pSS high fatigue patients were analysed versus controls (p = 0.002). One SNP in PKN1 displayed an association in the case-only analysis of pSS high fatigue versus pSS low fatigue (p = 0.005). This candidate gene study in pSS did reveal a trend for associations between genetic variation in candidate genes and fatigue. The results will need to be replicated. More research on genetic associations with fatigue is warranted, and future trials should include larger cohorts and multicentre collaborations with sharing of genetic material to increase the statistical power.

The genetic validation of heterogeneity in schizophrenia.

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Tsutsumi, Atsushi; Glatt, Stephen J; Kanazawa, Tetsufumi; Kawashige, Seiya; Uenishi, Hiroyuki; Hokyo, Akira; Kaneko, Takao; Moritani, Makiko; Kikuyama, Hiroki; Koh, Jun; Matsumura, Hitoshi; Yoneda, Hiroshi

2011-10-07

Schizophrenia is a heritable disorder, however clear genetic architecture has not been detected. To overcome this state of uncertainty, the SZGene database has been established by including all published case-control genetic association studies appearing in peer-reviewed journals. In the current study, we aimed to determine if genetic variants strongly suggested by SZGene are associated with risk of schizophrenia in our case-control samples of Japanese ancestry. In addition, by employing the additive model for aggregating the effect of seven variants, we aimed to verify the genetic heterogeneity of schizophrenia diagnosed by an operative diagnostic manual, the DSM-IV. Each positively suggested genetic polymorphism was ranked according to its p-value, then the seven top-ranked variants (p Japanese population. It is also important to aggregate the updated positive variants in the SZGene database when the replication work is conducted.

Non‐Canonical Replication Initiation: You’re Fired!

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Bazilė Ravoitytė

2017-01-01

Full Text Available The division of prokaryotic and eukaryotic cells produces two cells that inherit a perfect copy of the genetic material originally derived from the mother cell. The initiation of canonical DNA replication must be coordinated to the cell cycle to ensure the accuracy of genome duplication. Controlled replication initiation depends on a complex interplay of cis‐acting DNA sequences, the so‐called origins of replication (ori, with trans‐acting factors involved in the onset of DNA synthesis. The interplay of cis‐acting elements and trans‐acting factors ensures that cells initiate replication at sequence‐specific sites only once, and in a timely order, to avoid chromosomal endoreplication. However, chromosome breakage and excessive RNA:DNA hybrid formation can cause breakinduced (BIR or transcription‐initiated replication (TIR, respectively. These non‐canonical replication events are expected to affect eukaryotic genome function and maintenance, and could be important for genome evolution and disease development. In this review, we describe the difference between canonical and non‐canonical DNA replication, and focus on mechanistic differences and common features between BIR and TIR. Finally, we discuss open issues on the factors and molecular mechanisms involved in TIR.

The influence of familial factors on the intelligence-mortality association

DEFF Research Database (Denmark)

Christensen, G. T.; Osler, M.; Madsen, M.

2017-01-01

The aim was to investigate whether the widely reported inverse intelligence-mortality association could be replicated in twin intrapair analyses in which genetic and shared environmental factors are controlled for, as per the study design. Furthermore, the issue of generalizability of twin findings......-mortality associations were replicated in intrapair analyses of all twins and DZ twins where genetic and shared familial factors were partly controlled for, as per the study design. For twin pairs with a difference in intelligence test-score of half a standard deviation or more, the proportion of twin pairs in which...

Genetic moderation of effects of maternal sensitivity on girl's age of menarche: Replication of the Manuck et al. study.

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Hartman, Sarah; Widaman, Keith F; Belsky, Jay

2015-08-01

Manuck, Craig, Flory, Halder, and Ferrell (2011) reported that a theoretically anticipated effect of family rearing on girls' menarcheal age was genetically moderated by two single nucleotide polymorphisms (SNPs) of the estrogen receptor-α gene. We sought to replicate and extend these findings, studying 210 White females followed from birth. The replication was general because a different measure of the rearing environment was used in this inquiry (i.e., maternal sensitivity) than in the prior one (i.e., family cohesion). Extensions of the work included prospective rather than retrospective measurements of the rearing environment, reports of first menstruation within a year of its occurrence rather than decades later, accounting for some heritability of menarcheal age by controlling for maternal age of menarche, and using a new model-fitting approach to competitively compare diathesis-stress versus differential-susceptibility models of Gene × Environment interaction. The replication/extension effort proved successful in the case of both estrogen receptor-α SNPs, with the Gene × Environment interactions principally reflecting diathesis-stress: lower levels of maternal sensitivity predicted earlier age of menarche for girls homozygous for the minor alleles of either SNP but not for girls carrying other genotypes. Results are discussed in light of the new analytic methods adopted.

Cooperative working of bacterial chromosome replication proteins generated by a reconstituted protein expression system

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Fujiwara, Kei; Katayama, Tsutomu; Nomura, Shin-ichiro M.

2013-01-01

Replication of all living cells relies on the multirounds flow of the central dogma. Especially, expression of DNA replication proteins is a key step to circulate the processes of the central dogma. Here we achieved the entire sequential transcription–translation–replication process by autonomous expression of chromosomal DNA replication machineries from a reconstituted transcription–translation system (PURE system). We found that low temperature is essential to express a complex protein, DNA polymerase III, in a single tube using the PURE system. Addition of the 13 genes, encoding initiator, DNA helicase, helicase loader, RNA primase and DNA polymerase III to the PURE system gave rise to a DNA replication system by a coupling manner. An artificial genetic circuit demonstrated that the DNA produced as a result of the replication is able to provide genetic information for proteins, indicating the in vitro central dogma can sequentially undergo two rounds. PMID:23737447

Epigenome-wide association study of DNA methylation in narcolepsy: an integrated genetic and epigenetic approach.

Science.gov (United States)

Shimada, Mihoko; Miyagawa, Taku; Toyoda, Hiromi; Tokunaga, Katsushi; Honda, Makoto

2018-04-01

Narcolepsy with cataplexy, which is a hypersomnia characterized by excessive daytime sleepiness and cataplexy, is a multifactorial disease caused by both genetic and environmental factors. Several genetic factors including HLA-DQB1*06:02 have been identified; however, the disease etiology is still unclear. Epigenetic modifications, such as DNA methylation, have been suggested to play an important role in the pathogenesis of complex diseases. Here, we examined DNA methylation profiles of blood samples from narcolepsy and healthy control individuals and performed an epigenome-wide association study (EWAS) to investigate methylation loci associated with narcolepsy. Moreover, data from the EWAS and a previously performed narcolepsy genome-wide association study were integrated to search for methylation loci with causal links to the disease. We found that (1) genes annotated to the top-ranked differentially methylated positions (DMPs) in narcolepsy were associated with pathways of hormone secretion and monocarboxylic acid metabolism. (2) Top-ranked narcolepsy-associated DMPs were significantly more abundant in non-CpG island regions and more than 95 per cent of such sites were hypomethylated in narcolepsy patients. (3) The integrative analysis identified the CCR3 region where both a single methylation site and multiple single-nucleotide polymorphisms were found to be associated with the disease as a candidate region responsible for narcolepsy. The findings of this study suggest the importance of future replication studies, using methylation technologies with wider genome coverage and/or larger number of samples, to confirm and expand on these results.

Alzheimer's Disease Sequencing Project discovery and replication criteria for cases and controls: Data from a community-based prospective cohort study with autopsy follow-up.

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Crane, Paul K; Foroud, Tatiana; Montine, Thomas J; Larson, Eric B

2017-12-01

The Alzheimer's Disease Sequencing Project (ADSP) used different criteria for assigning case and control status from the discovery and replication phases of the project. We considered data from a community-based prospective cohort study with autopsy follow-up where participants could be categorized as case, control, or neither by both definitions and compared the two sets of criteria. We used data from the Adult Changes in Thought (ACT) study including Diagnostic and Statistical Manual-IV criteria for dementia status, McKhann et al. criteria for clinical Alzheimer's disease, and Braak and Consortium to Establish a Registry for AD findings on neurofibrillary tangles and neuritic plaques to categorize the 621 ACT participants of European ancestry who died and came to autopsy. We applied ADSP discovery and replication definitions to identify controls, cases, and people who were neither controls nor cases. There was some agreement between the discovery and replication definitions. Major areas of discrepancy included the finding that only 40% of the discovery sample controls had sufficiently low levels of neurofibrillary tangles and neuritic plaques to be considered controls by the replication criteria and the finding that 16% of the replication phase cases were diagnosed with non-AD dementia during life and thus were excluded as cases for the discovery phase. These findings should inform interpretation of genetic association findings from the ADSP. Differences in genetic association findings between the two phases of the study may reflect these different phenotype definitions from the discovery and replication phase of the ADSP. Copyright © 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Evolving temporal association rules with genetic algorithms

OpenAIRE

Matthews, Stephen G.; Gongora, Mario A.; Hopgood, Adrian A.

2010-01-01

A novel framework for mining temporal association rules by discovering itemsets with a genetic algorithm is introduced. Metaheuristics have been applied to association rule mining, we show the efficacy of extending this to another variant - temporal association rule mining. Our framework is an enhancement to existing temporal association rule mining methods as it employs a genetic algorithm to simultaneously search the rule space and temporal space. A methodology for validating the ability of...

Genetic association studies of glutamate, GABA and related genes in schizophrenia and bipolar disorder: a decade of advance.

Science.gov (United States)

Cherlyn, Suat Ying Tan; Woon, Puay San; Liu, Jian Jun; Ong, Wei Yi; Tsai, Guo Chuan; Sim, Kang

2010-05-01

Schizophrenia (SZ) and bipolar disorder (BD) are debilitating neurobehavioural disorders likely influenced by genetic and non-genetic factors and which can be seen as complex disorders of synaptic neurotransmission. The glutamatergic and GABAergic neurotransmission systems have been implicated in both diseases and we have reviewed extensive literature over a decade for evidence to support the association of glutamate and GABA genes in SZ and BD. Candidate-gene based population and family association studies have implicated some ionotrophic glutamate receptor genes (GRIN1, GRIN2A, GRIN2B and GRIK3), metabotropic glutamate receptor genes (such as GRM3), the G72/G30 locus and GABAergic genes (e.g. GAD1 and GABRB2) in both illnesses to varying degrees, but further replication studies are needed to validate these results. There is at present no consensus on specific single nucleotide polymorphisms or haplotypes associated with the particular candidate gene loci in these illnesses. The genetic architecture of glutamate systems in bipolar disorder need to be better studied in view of recent data suggesting an overlap in the genetic aetiology of SZ and BD. There is a pressing need to integrate research platforms in genomics, epistatic models, proteomics, metabolomics, neuroimaging technology and translational studies in order to allow a more integrated understanding of glutamate and GABAergic signalling processes and aberrations in SZ and BD as well as their relationships with clinical presentations and treatment progress over time. (c) 2010 Elsevier Ltd. All rights reserved.

Variability, heritability and genetic association in vegetable amaranth (Amaranthus tricolor L.)

Energy Technology Data Exchange (ETDEWEB)

Sarker, U.; Islam, Md T.; Rabbani, Md G.; Oba, S.

2015-07-01

Forty three vegetable amaranth (Amaranthus tricolor L.) genotypes selected from different eco-geographic regions of Bangladesh were evaluated during 3 years (2012-2014) for genetic variability, heritability and genetic association among mineral elements and quality and agronomic traits in randomized complete block design (RCBD) with five replications. The analysis showed that vegetable amaranth is a rich source of K, Ca, Mg, proteins and dietary fibre with average values among the 43 genotypes (1.014%, 2.476%, 2.984, 1.258% and 7.81%, respectively). Six genotypes (VA13, VA14, VA16, VA18, VA26, VA27) showed a biological yield >2000 g/m2 and high mineral, protein and dietary fibre contents; eleven genotypes had high amount of minerals, protein and dietary fibre with above average biological yield; nine genotypes had below average biological yield but were rich in minerals, protein and dietary fibre. Biological yield exhibited a strong positive correlation with leaf area, shoot weight, shoot/root weight and stem base diameter. Insignificant genotypic correlation was observed among mineral, quality and agronomic traits, except K vs. Mg, protein vs. dietary fibre and stem base diameter vs. Ca. Some of these genotypes can be used for improvement of vegetable amaranth regarding mineral, protein and dietary fibre content without compromising yield loss. (Author)

Hydroxyurea-Induced Replication Stress

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Kenza Lahkim Bennani-Belhaj

2010-01-01

Full Text Available Bloom's syndrome (BS displays one of the strongest known correlations between chromosomal instability and a high risk of cancer at an early age. BS cells combine a reduced average fork velocity with constitutive endogenous replication stress. However, the response of BS cells to replication stress induced by hydroxyurea (HU, which strongly slows the progression of replication forks, remains unclear due to publication of conflicting results. Using two different cellular models of BS, we showed that BLM deficiency is not associated with sensitivity to HU, in terms of clonogenic survival, DSB generation, and SCE induction. We suggest that surviving BLM-deficient cells are selected on the basis of their ability to deal with an endogenous replication stress induced by replication fork slowing, resulting in insensitivity to HU-induced replication stress.

Reactivation and Lytic Replication of Kaposi’s Sarcoma-Associated Herpesvirus: An Update

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Aneja, Kawalpreet K.; Yuan, Yan

2017-01-01

The life cycle of Kaposi’s sarcoma-associated herpesvirus (KSHV) consists of two phases, latent and lytic. The virus establishes latency as a strategy for avoiding host immune surveillance and fusing symbiotically with the host for lifetime persistent infection. However, latency can be disrupted and KSHV is reactivated for entry into the lytic replication. Viral lytic replication is crucial for efficient dissemination from its long-term reservoir to the sites of disease and for the spread of the virus to new hosts. The balance of these two phases in the KSHV life cycle is important for both the virus and the host and control of the switch between these two phases is extremely complex. Various environmental factors such as oxidative stress, hypoxia, and certain chemicals have been shown to switch KSHV from latency to lytic reactivation. Immunosuppression, unbalanced inflammatory cytokines, and other viral co-infections also lead to the reactivation of KSHV. This review article summarizes the current understanding of the initiation and regulation of KSHV reactivation and the mechanisms underlying the process of viral lytic replication. In particular, the central role of an immediate-early gene product RTA in KSHV reactivation has been extensively investigated. These studies revealed multiple layers of regulation in activation of RTA as well as the multifunctional roles of RTA in the lytic replication cascade. Epigenetic regulation is known as a critical layer of control for the switch of KSHV between latency and lytic replication. The viral non-coding RNA, PAN, was demonstrated to play a central role in the epigenetic regulation by serving as a guide RNA that brought chromatin remodeling enzymes to the promoters of RTA and other lytic genes. In addition, a novel dimension of regulation by microPeptides emerged and has been shown to regulate RTA expression at the protein level. Overall, extensive investigation of KSHV reactivation and lytic replication has revealed

Genetic and Non-genetic Factors Associated WithConstipation in Cancer Patients Receiving Opioids

OpenAIRE

Laugsand, Eivor Alette; Skorpen, Frank; Kaasa, Stein; Sabatowski, Rainer; Strasser, Florian; Fayers, Peter; Klepstad, Pål

2015-01-01

Objectives: To examine whether the inter-individual variation in constipation among patients receiving opioids for cancer pain is associated with genetic or non-genetic factors. Methods: Cancer patients receiving opioids were included from 17 centers in 11 European countries. Intensity of constipation was reported by 1,568 patients on a four-point categorical scale. Non-genetic factors were included as covariates in stratified regression analyses on the association between constipation a...

Different domains of P21Cip1/waf1 regulate DNA replication and DNA repair-associated processes after UV

International Nuclear Information System (INIS)

Soria, Gaston; Speroni, Juliana; Podhajcer, Osvaldo L.; Gottifredi, Vanesa; Prives, Carol

2007-01-01

Full text: Many genotoxic insults result in p21 up-regulation and p21-dependent cell cycle arrest but UV irradiation triggers p21 proteolysis. The significance of the increased p21 turnover is unclear and might be associated to DNA repair. While the role of p21 in Nucleotide Excision Repair (NER) remains controversial, two recent reports explore its effect on Translesion DNA Synthesis (TLS), a process that avoids replication blockage during S phase. The first report shows that p21 degradation is required for efficient PCNA ubiquitination, a post transcriptional modification that is relevant for TLS. The second report demonstrates that p21 (-/-) cells have increased TLS-associated mutagenic rates. Herein we analyze the effect of p21 on different PCNA-driven processes including DNA replication, NER and TLS. Whereas only the CDK binding domain of p21 is required for cell cycle arrest in unstressed cells; neither the CDK- nor the PCNA-binding domains of p21 are able to block early and late steps of NER. Intriguingly, through its PCNA binding domain, p21 inhibited recruitment of the TLS-polymerase, polη to PCNA foci after UV. Moreover, this obstruction correlates with accumulation of γH2AX and increased apoptosis. Taking together, our data emphasizes the link between p21 turnover and efficient TLS. This might also suggest a potential effect of p21 on other activities of polζ, a DNA polymerase with central roles in other biological scenarios such as genetic conversion, homologous recombination and modulation of the cellular response to genotoxic agents [es

Inhibition of DNA2 nuclease as a therapeutic strategy targeting replication stress in cancer cells.

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Kumar, S; Peng, X; Daley, J; Yang, L; Shen, J; Nguyen, N; Bae, G; Niu, H; Peng, Y; Hsieh, H-J; Wang, L; Rao, C; Stephan, C C; Sung, P; Ira, G; Peng, G

2017-04-17

Replication stress is a characteristic feature of cancer cells, which is resulted from sustained proliferative signaling induced by activation of oncogenes or loss of tumor suppressors. In cancer cells, oncogene-induced replication stress manifests as replication-associated lesions, predominantly double-strand DNA breaks (DSBs). An essential mechanism utilized by cells to repair replication-associated DSBs is homologous recombination (HR). In order to overcome replication stress and survive, cancer cells often require enhanced HR repair capacity. Therefore, the key link between HR repair and cellular tolerance to replication-associated DSBs provides us with a mechanistic rationale for exploiting synthetic lethality between HR repair inhibition and replication stress. DNA2 nuclease is an evolutionarily conserved essential enzyme in replication and HR repair. Here we demonstrate that DNA2 is overexpressed in pancreatic cancers, one of the deadliest and more aggressive forms of human cancers, where mutations in the KRAS are present in 90-95% of cases. In addition, depletion of DNA2 significantly reduces pancreatic cancer cell survival and xenograft tumor growth, suggesting the therapeutic potential of DNA2 inhibition. Finally, we develop a robust high-throughput biochemistry assay to screen for inhibitors of the DNA2 nuclease activity. The top inhibitors were shown to be efficacious against both yeast Dna2 and human DNA2. Treatment of cancer cells with DNA2 inhibitors recapitulates phenotypes observed upon DNA2 depletion, including decreased DNA double strand break end resection and attenuation of HR repair. Similar to genetic ablation of DNA2, chemical inhibition of DNA2 selectively attenuates the growth of various cancer cells with oncogene-induced replication stress. Taken together, our findings open a new avenue to develop a new class of anticancer drugs by targeting druggable nuclease DNA2. We propose DNA2 inhibition as new strategy in cancer therapy by targeting

Lack of replication of thirteen single-nucleotide polymorphisms implicated in Parkinson’s disease: a large-scale international study

Science.gov (United States)

Elbaz, Alexis; Nelson, Lorene M; Payami, Haydeh; Ioannidis, John P A; Fiske, Brian K; Annesi, Grazia; Belin, Andrea Carmine; Factor, Stewart A; Ferrarese, Carlo; Hadjigeorgiou, Georgios M; Higgins, Donald S; Kawakami, Hideshi; Krüger, Rejko; Marder, Karen S; Mayeux, Richard P; Mellick, George D; Nutt, John G; Ritz, Beate; Samii, Ali; Tanner, Caroline M; Van Broeckhoven, Christine; Van Den Eeden, Stephen K; Wirdefeldt, Karin; Zabetian, Cyrus P; Dehem, Marie; Montimurro, Jennifer S; Southwick, Audrey; Myers, Richard M; Trikalinos, Thomas A

2013-01-01

Summary Background A genome-wide association study identified 13 single-nucleotide polymorphisms (SNPs) significantly associated with Parkinson’s disease. Small-scale replication studies were largely non-confirmatory, but a meta-analysis that included data from the original study could not exclude all SNP associations, leaving relevance of several markers uncertain. Methods Investigators from three Michael J Fox Foundation for Parkinson’s Research-funded genetics consortia—comprising 14 teams—contributed DNA samples from 5526 patients with Parkinson’s disease and 6682 controls, which were genotyped for the 13 SNPs. Most (88%) participants were of white, non-Hispanic descent. We assessed log-additive genetic effects using fixed and random effects models stratified by team and ethnic origin, and tested for heterogeneity across strata. A meta-analysis was undertaken that incorporated data from the original genome-wide study as well as subsequent replication studies. Findings In fixed and random-effects models no associations with any of the 13 SNPs were identified (odds ratios 0·89 to 1·09). Heterogeneity between studies and between ethnic groups was low for all SNPs. Subgroup analyses by age at study entry, ethnic origin, sex, and family history did not show any consistent associations. In our meta-analysis, no SNP showed significant association (summary odds ratios 0·95 to 1.08); there was little heterogeneity except for SNP rs7520966. Interpretation Our results do not lend support to the finding that the 13 SNPs reported in the original genome-wide association study are genetic susceptibility factors for Parkinson’s disease. PMID:17052658

Replication of genome wide association studies on hepatocellular carcinoma susceptibility loci of STAT4 and HLA-DQ in a Korean population.

Science.gov (United States)

Kim, Lyoung Hyo; Cheong, Hyun Sub; Namgoong, Suhg; Kim, Ji On; Kim, Jeong-Hyun; Park, Byung Lae; Cho, Sung Won; Park, Neung Hwa; Cheong, Jae Youn; Koh, InSong; Shin, Hyoung Doo; Kim, Yoon-Jun

2015-07-01

A recent genome-wide association study (GWAS) for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) identified two loci (rs7574865 in STAT4 and rs9275319 in HLA-DQ) in a Chinese population. We attempted to replicate the associations between the two SNP loci and the risk of HCC in a Korean population. The rs7574865 in STAT4 and rs9275319 in HLA-DQ were genotyped in a total of 3838 Korean subjects composed of 287 HBV-related hepatocellular carcinoma patients, 671 chronic hepatitis B virus (CHB) patients, and 2880 population controls using TaqMan genotyping assay. Gene expression was measured by microarray. A logistic regression analysis revealed that rs7574865 in STAT4 and rs9275319 in HLA-DQ were associated with the risk of CHB (OR = 1.25, P = 0.0002 and OR = 1.57, P= 1.44 × 10(-10), respectively). However, these loci were no association with the risk of HBV-related HCC among CHB patients. In the gene expression analyses, although no significant differences in mRNA expression of nearby genes according to genotypes were detected, a significantly decreased mRNA expression in HCC subjects was observed in STAT4, HLA-DQA1, and HLA-DQB1. Although the genetic effects of two HCC susceptibility loci were not replicated, the two loci were found to exert susceptibility effects on the risk of CHB in a Korean population. In addition, the decreased mRNA expression of STAT4, HLA-DQA1, and HLA-DQB1 in HCC tissue might provide a clue to understanding their role in the progression to HCC. Copyright © 2015 Elsevier B.V. All rights reserved.

Comprehensive genetic assessment of a functional TLR9 promoter polymorphism: no replicable association with asthma or asthma-related phenotypes

Directory of Open Access Journals (Sweden)

Celedón Juan C

2011-02-01

Full Text Available Abstract Background Prior studies suggest a role for a variant (rs5743836 in the promoter of toll-like receptor 9 (TLR9 in asthma and other inflammatory diseases. We performed detailed genetic association studies of the functional variant rs5743836 with asthma susceptibility and asthma-related phenotypes in three independent cohorts. Methods rs5743836 was genotyped in two family-based cohorts of children with asthma and a case-control study of adult asthmatics. Association analyses were performed using chi square, family-based and population-based testing. A luciferase assay was performed to investigate whether rs5743836 genotype influences TLR9 promoter activity. Results Contrary to prior reports, rs5743836 was not associated with asthma in any of the three cohorts. Marginally significant associations were found with FEV1 and FVC (p = 0.003 and p = 0.008, respectively in one of the family-based cohorts, but these associations were not significant after correcting for multiple comparisons. Higher promoter activity of the CC genotype was demonstrated by luciferase assay, confirming the functional importance of this variant. Conclusion Although rs5743836 confers regulatory effects on TLR9 transcription, this variant does not appear to be an important asthma-susceptibility locus.

A unique epigenetic signature is associated with active DNA replication loci in human embryonic stem cells.

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Li, Bing; Su, Trent; Ferrari, Roberto; Li, Jing-Yu; Kurdistani, Siavash K

2014-02-01

The cellular epigenetic landscape changes as pluripotent stem cells differentiate to somatic cells or when differentiated cells transform to a cancerous state. These epigenetic changes are commonly correlated with differences in gene expression. Whether active DNA replication is also associated with distinct chromatin environments in these developmentally and phenotypically diverse cell types has not been known. Here, we used BrdU-seq to map active DNA replication loci in human embryonic stem cells (hESCs), normal primary fibroblasts and a cancer cell line, and correlated these maps to the epigenome. In all cell lines, the majority of BrdU peaks were enriched in euchromatin and at DNA repetitive elements, especially at microsatellite repeats, and coincided with previously determined replication origins. The most prominent BrdU peaks were shared between all cells but a sizable fraction of the peaks were specific to each cell type and associated with cell type-specific genes. Surprisingly, the BrdU peaks that were common to all cell lines were associated with H3K18ac, H3K56ac, and H4K20me1 histone marks only in hESCs but not in normal fibroblasts or cancer cells. Depletion of the histone acetyltransferases for H3K18 and H3K56 dramatically decreased the number and intensity of BrdU peaks in hESCs. Our data reveal a unique epigenetic signature that distinguishes active replication loci in hESCs from normal somatic or malignant cells.

New developments in genetics of myositis.

Science.gov (United States)

Rothwell, Simon; Lamb, Janine A; Chinoy, Hector

2016-11-01

This article reviews the advances that have been made in our understanding of the genetics of the idiopathic inflammatory myopathies (IIM) in the past 2 years, with a particular focus on polymyositis, dermatomyositis and inclusion body myositis. Two large human leukocyte antigen (HLA) imputation studies have confirmed a strong association with the 8.1 ancestral haplotype in clinical subgroups of myositis and suggest multiple independent associations on this haplotype. Risk in these genes may be due to specific amino acid positions within the peptide-binding grooves of HLA molecules. A large genetic study in 2566 IIM patients revealed associations such as PTPN22, STAT4, UBE2L3 and BLK, which overlap with risk variants reported in other seropositive autoimmune diseases. There is also evidence of different genetic architectures in clinical subgroups of IIM. Candidate gene studies in the Japanese and Chinese populations have replicated previous IIM associations which suggest common aetiology between ethnicities. International collaborations have facilitated large genetic studies in IIM that have revealed much about the genetics of this rare complex disease both within the HLA region and genome-wide. Future approaches, such as sequencing and trans-ethnic meta-analyses, will advance our knowledge of IIM genetics.

Homologous Recombination as a Replication Fork Escort: Fork-Protection and Recovery

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Audrey Costes

2012-12-01

Full Text Available Homologous recombination is a universal mechanism that allows DNA repair and ensures the efficiency of DNA replication. The substrate initiating the process of homologous recombination is a single-stranded DNA that promotes a strand exchange reaction resulting in a genetic exchange that promotes genetic diversity and DNA repair. The molecular mechanisms by which homologous recombination repairs a double-strand break have been extensively studied and are now well characterized. However, the mechanisms by which homologous recombination contribute to DNA replication in eukaryotes remains poorly understood. Studies in bacteria have identified multiple roles for the machinery of homologous recombination at replication forks. Here, we review our understanding of the molecular pathways involving the homologous recombination machinery to support the robustness of DNA replication. In addition to its role in fork-recovery and in rebuilding a functional replication fork apparatus, homologous recombination may also act as a fork-protection mechanism. We discuss that some of the fork-escort functions of homologous recombination might be achieved by loading of the recombination machinery at inactivated forks without a need for a strand exchange step; as well as the consequence of such a model for the stability of eukaryotic genomes.

Elg1 forms an alternative RFC complex important for DNA replication and genome integrity

NARCIS (Netherlands)

Bellaoui, Mohammed; Chang, Michael; Ou, Jiongwen; Xu, Hong; Boone, Charles; Brown, Grant W

2003-01-01

Genome-wide synthetic genetic interaction screens with mutants in the mus81 and mms4 replication fork-processing genes identified a novel replication factor C (RFC) homolog, Elg1, which forms an alternative RFC complex with Rfc2-5. This complex is distinct from the DNA replication RFC, the DNA

Jnk2 effects on tumor development, genetic instability and replicative stress in an oncogene-driven mouse mammary tumor model.

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Peila Chen

2010-05-01

Full Text Available Oncogenes induce cell proliferation leading to replicative stress, DNA damage and genomic instability. A wide variety of cellular stresses activate c-Jun N-terminal kinase (JNK proteins, but few studies have directly addressed the roles of JNK isoforms in tumor development. Herein, we show that jnk2 knockout mice expressing the Polyoma Middle T Antigen transgene developed mammary tumors earlier and experienced higher tumor multiplicity compared to jnk2 wildtype mice. Lack of jnk2 expression was associated with higher tumor aneuploidy and reduced DNA damage response, as marked by fewer pH2AX and 53BP1 nuclear foci. Comparative genomic hybridization further confirmed increased genomic instability in PyV MT/jnk2-/- tumors. In vitro, PyV MT/jnk2-/- cells underwent replicative stress and cell death as evidenced by lower BrdU incorporation, and sustained chromatin licensing and DNA replication factor 1 (CDT1 and p21(Waf1 protein expression, and phosphorylation of Chk1 after serum stimulation, but this response was not associated with phosphorylation of p53 Ser15. Adenoviral overexpression of CDT1 led to similar differences between jnk2 wildtype and knockout cells. In normal mammary cells undergoing UV induced single stranded DNA breaks, JNK2 localized to RPA (Replication Protein A coated strands indicating that JNK2 responds early to single stranded DNA damage and is critical for subsequent recruitment of DNA repair proteins. Together, these data support that JNK2 prevents replicative stress by coordinating cell cycle progression and DNA damage repair mechanisms.

Population genetic structure in Atlantic and Pacific Ocean common murres (Uria aalge): Natural replicate tests of post-Pleistocene evolution

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Morris-Pocock, J. A.; Taylor, S.A.; Birt, T.P.; Damus, M.; Piatt, John F.; Warheit, K.I.; Friesen, Vicki L.

2008-01-01

Understanding the factors that influence population differentiation in temperate taxa can be difficult because the signatures of both historic and contemporary demographics are often reflected in population genetic patterns. Fortunately, analyses based on coalescent theory can help untangle the relative influence of these historic and contemporary factors. Common murres (Uria aalge) are vagile seabirds that breed in the boreal and low arctic waters of the Northern Hemisphere. Previous analyses revealed that Atlantic and Pacific populations are genetically distinct; however, less is known about population genetic structure within ocean basins. We employed the mitochondrial control region, four microsatellite loci and four intron loci to investigate population genetic structure throughout the range of common murres. As in previous studies, we found that Atlantic and Pacific populations diverged during the Pleistocene and do not currently exchange migrants. Therefore, Atlantic and Pacific murre populations can be used as natural replicates to test mechanisms of population differentiation. While we found little population genetic structure within the Pacific, we detected significant east-west structuring among Atlantic colonies. The degree that population genetic structure reflected contemporary population demographics also differed between ocean basins. Specifically, while the low levels of population differentiation in the Pacific are at least partially due to high levels of contemporary gene flow, the east-west structuring of populations within the Atlantic appears to be the result of historic fragmentation of populations rather than restricted contemporary gene flow. The contrasting results in the Atlantic and Pacific Oceans highlight the necessity of carefully considering multilocus nonequilibrium population genetic approaches when reconstructing the demographic history of temperate Northern Hemisphere taxa. ?? 2008 The Authors.

Piper betle L. Modulates Senescence-Associated Genes Expression in Replicative Senescent Human Diploid Fibroblasts

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Lina Wati Durani

2017-01-01

Full Text Available Piper betle (PB is a traditional medicine that is widely used to treat different diseases around Asian region. The leaf extracts contain various bioactive compounds, which were reported to have antidiabetic, antibacterial, anti-inflammatory, antioxidant, and anticancer effects. In this study, the effect of PB aqueous extracts on replicative senescent human diploid fibroblasts (HDFs was investigated by determining the expressions of senescence-associated genes using quantitative PCR. Our results showed that PB extracts at 0.4 mg/ml can improve cell proliferation of young (143%, presenescent (127.3%, and senescent (157.3% HDFs. Increased expressions of PRDX6, TP53, CDKN2A, PAK2, and MAPK14 were observed in senescent HDFs compared to young and/or presenescent HDFs. Treatment with PB extracts modulates the transcriptional profile changes in senescent HDFs. By contrast, expressions of SOD1 increased, whereas GPX1, PRDX6, TP53, CDKN2A, PAK2, and MAPK14 were decreased in PB-treated senescent HDFs compared to untreated senescent HDFs. In conclusion, this study indicates the modulation of PB extracts on senescence-associated genes expression of replicative senescent HDFs. Further studies warrant determining the mechanism of PB in modulating replicative senescence of HDFs through these signaling pathways.

Piper betle L. Modulates Senescence-Associated Genes Expression in Replicative Senescent Human Diploid Fibroblasts.

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Durani, Lina Wati; Khor, Shy Cian; Tan, Jen Kit; Chua, Kien Hui; Mohd Yusof, Yasmin Anum; Makpol, Suzana

2017-01-01

Piper betle (PB) is a traditional medicine that is widely used to treat different diseases around Asian region. The leaf extracts contain various bioactive compounds, which were reported to have antidiabetic, antibacterial, anti-inflammatory, antioxidant, and anticancer effects. In this study, the effect of PB aqueous extracts on replicative senescent human diploid fibroblasts (HDFs) was investigated by determining the expressions of senescence-associated genes using quantitative PCR. Our results showed that PB extracts at 0.4 mg/ml can improve cell proliferation of young (143%), presenescent (127.3%), and senescent (157.3%) HDFs. Increased expressions of PRDX6 , TP53 , CDKN2A , PAK2 , and MAPK14 were observed in senescent HDFs compared to young and/or presenescent HDFs. Treatment with PB extracts modulates the transcriptional profile changes in senescent HDFs. By contrast, expressions of SOD1 increased, whereas GPX1 , PRDX6 , TP53 , CDKN2A , PAK2 , and MAPK14 were decreased in PB-treated senescent HDFs compared to untreated senescent HDFs. In conclusion, this study indicates the modulation of PB extracts on senescence-associated genes expression of replicative senescent HDFs. Further studies warrant determining the mechanism of PB in modulating replicative senescence of HDFs through these signaling pathways.

Role of genetics in infection-associated arthritis.

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Benham, Helen; Robinson, Philip C; Baillet, Athan C; Rehaume, Linda M; Thomas, Ranjeny

2015-04-01

Genetic discoveries in arthritis and their associated biological pathways spanning the innate and adaptive immune system demonstrate the strong association between susceptibility to arthritis and control of exogenous organisms. The canonical theory of the aetiology of immune-mediated arthritis and other immune-mediated diseases is that the introduction of exogenous antigenic stimuli to a genetically susceptible host sets up the environment for an abnormal immune response manifesting as disease. A disruption in host-microbe homeostasis driven by disease-associated genetic variants could ultimately provide the source of exogenous antigen triggering disease development. We discuss genetic variants impacting the innate and adaptive arms of the immune system and their relationship to microbial control and arthritic disease. We go on to consider the evidence for a relationship between HLA-B27, infection and arthritis, and then emerging evidence for an interaction between microbiota and rheumatoid arthritis. Copyright © 2015 Elsevier Ltd. All rights reserved.

The p150 subunit of CAF-1 causes association of SUMO2/3 with the DNA replication foci

International Nuclear Information System (INIS)

Uwada, Junsuke; Tanaka, Niina; Yamaguchi, Yutaro; Uchimura, Yasuhiro; Shibahara, Kei-ichi; Nakao, Mitsuyoshi; Saitoh, Hisato

2010-01-01

The small ubiquitin-related modifier 2/3 (SUMO2/3) can be post-translationally conjugated to a wide variety of proteins constituting chromatin, the platform for genetic and epigenetic regulation. Nevertheless, it is unclear how SUMO2/3 and SUMO2/3-modified proteins are delivered to the chromatin fibers. Here we report that the largest subunit of chromatin assembly factor 1 (CAF-1), human p150, interacts directly and preferentially with SUMO2/3. Amino acid residue of 98-105 in p150 is essential and sufficient for SUMO2/3 interaction. p150-SUMO2/3 interaction coincided with regions that replicate chromatin fibers, because accumulation of the proliferating cell nuclear antigen (PCNA), and incorporation of bromodeoxyuridine (BrdU) were detected at foci co-localized with both p150 and SUMO2/3 during the S-phase in a cell line expressing epitope-tagged p150. Although inhibition of SUMO2/3 expression had only a small effect on p150 deposition on the replication sites, depletion of p150 led to delocalization of SUMO2/3 from the replication foci. Furthermore, p150 mutants deficient in SUMO2/3 interaction, caused a major reduction of SUMO2/3 at the replication foci. Thus, our findings suggest an expanded role of p150 as a SUMO2/3-interacting factor, and raise the intriguing possibility that p150 plays a role in promoting delivery of SUMO2/3 or SUMO2/3-modified proteins (or both) on chromatin fibers during replication.

Distinct functions of human RecQ helicases during DNA replication

Czech Academy of Sciences Publication Activity Database

Urban, Václav; Dobrovolná, Jana; Janščák, Pavel

2017-01-01

Roč. 225, červen (2017), s. 20-26 ISSN 0301-4622 R&D Projects: GA ČR(CZ) GA14-05743S; GA MŠk LH14037 Institutional support: RVO:68378050 Keywords : DNA replication * Replication stress * RecQ helicases * Genomic instability * Cancer Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 2.402, year: 2016

Covariance Association Test (CVAT) Identifies Genetic Markers Associated with Schizophrenia in Functionally Associated Biological Processes.

Science.gov (United States)

Rohde, Palle Duun; Demontis, Ditte; Cuyabano, Beatriz Castro Dias; Børglum, Anders D; Sørensen, Peter

2016-08-01

Schizophrenia is a psychiatric disorder with large personal and social costs, and understanding the genetic etiology is important. Such knowledge can be obtained by testing the association between a disease phenotype and individual genetic markers; however, such single-marker methods have limited power to detect genetic markers with small effects. Instead, aggregating genetic markers based on biological information might increase the power to identify sets of genetic markers of etiological significance. Several set test methods have been proposed: Here we propose a new set test derived from genomic best linear unbiased prediction (GBLUP), the covariance association test (CVAT). We compared the performance of CVAT to other commonly used set tests. The comparison was conducted using a simulated study population having the same genetic parameters as for schizophrenia. We found that CVAT was among the top performers. When extending CVAT to utilize a mixture of SNP effects, we found an increase in power to detect the causal sets. Applying the methods to a Danish schizophrenia case-control data set, we found genomic evidence for association of schizophrenia with vitamin A metabolism and immunological responses, which previously have been implicated with schizophrenia based on experimental and observational studies. Copyright © 2016 by the Genetics Society of America.

Identification of novel genetic Loci associated with thyroid peroxidase antibodies and clinical thyroid disease.

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Marco Medici

2014-02-01

Full Text Available Autoimmune thyroid diseases (AITD are common, affecting 2-5% of the general population. Individuals with positive thyroid peroxidase antibodies (TPOAbs have an increased risk of autoimmune hypothyroidism (Hashimoto's thyroiditis, as well as autoimmune hyperthyroidism (Graves' disease. As the possible causative genes of TPOAbs and AITD remain largely unknown, we performed GWAS meta-analyses in 18,297 individuals for TPOAb-positivity (1769 TPOAb-positives and 16,528 TPOAb-negatives and in 12,353 individuals for TPOAb serum levels, with replication in 8,990 individuals. Significant associations (P<5×10(-8 were detected at TPO-rs11675434, ATXN2-rs653178, and BACH2-rs10944479 for TPOAb-positivity, and at TPO-rs11675434, MAGI3-rs1230666, and KALRN-rs2010099 for TPOAb levels. Individual and combined effects (genetic risk scores of these variants on (subclinical hypo- and hyperthyroidism, goiter and thyroid cancer were studied. Individuals with a high genetic risk score had, besides an increased risk of TPOAb-positivity (OR: 2.18, 95% CI 1.68-2.81, P = 8.1×10(-8, a higher risk of increased thyroid-stimulating hormone levels (OR: 1.51, 95% CI 1.26-1.82, P = 2.9×10(-6, as well as a decreased risk of goiter (OR: 0.77, 95% CI 0.66-0.89, P = 6.5×10(-4. The MAGI3 and BACH2 variants were associated with an increased risk of hyperthyroidism, which was replicated in an independent cohort of patients with Graves' disease (OR: 1.37, 95% CI 1.22-1.54, P = 1.2×10(-7 and OR: 1.25, 95% CI 1.12-1.39, P = 6.2×10(-5. The MAGI3 variant was also associated with an increased risk of hypothyroidism (OR: 1.57, 95% CI 1.18-2.10, P = 1.9×10(-3. This first GWAS meta-analysis for TPOAbs identified five newly associated loci, three of which were also associated with clinical thyroid disease. With these markers we identified a large subgroup in the general population with a substantially increased risk of TPOAbs. The results provide insight into why

A genome-wide association study identifies rs2000999 as a strong genetic determinant of circulating haptoglobin levels.

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Philippe Froguel

Full Text Available Haptoglobin is an acute phase inflammatory marker. Its main function is to bind hemoglobin released from erythrocytes to aid its elimination, and thereby haptoglobin prevents the generation of reactive oxygen species in the blood. Haptoglobin levels have been repeatedly associated with a variety of inflammation-linked infectious and non-infectious diseases, including malaria, tuberculosis, human immunodeficiency virus, hepatitis C, diabetes, carotid atherosclerosis, and acute myocardial infarction. However, a comprehensive genetic assessment of the inter-individual variability of circulating haptoglobin levels has not been conducted so far.We used a genome-wide association study initially conducted in 631 French children followed by a replication in three additional European sample sets and we identified a common single nucleotide polymorphism (SNP, rs2000999 located in the Haptoglobin gene (HP as a strong genetic predictor of circulating Haptoglobin levels (P(overall = 8.1 × 10(-59, explaining 45.4% of its genetic variability (11.8% of Hp global variance. The functional relevance of rs2000999 was further demonstrated by its specific association with HP mRNA levels (β = 0.23 ± 0.08, P = 0.007. Finally, SNP rs2000999 was associated with decreased total and low-density lipoprotein cholesterol in 8,789 European children (P(total cholesterol = 0.002 and P(LDL = 0.0008.Given the central position of haptoglobin in many inflammation-related metabolic pathways, the relevance of rs2000999 genotyping when evaluating haptoglobin concentration should be further investigated in order to improve its diagnostic/therapeutic and/or prevention impact.

Intramolecular telomeric G-quadruplexes dramatically inhibit DNA synthesis by replicative and translesion polymerases, revealing their potential to lead to genetic change.

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Deanna N Edwards

Full Text Available Recent research indicates that hundreds of thousands of G-rich sequences within the human genome have the potential to form secondary structures known as G-quadruplexes. Telomeric regions, consisting of long arrays of TTAGGG/AATCCC repeats, are among the most likely areas in which these structures might form. Since G-quadruplexes assemble from certain G-rich single-stranded sequences, they might arise when duplex DNA is unwound such as during replication. Coincidentally, these bulky structures when present in the DNA template might also hinder the action of DNA polymerases. In this study, single-stranded telomeric templates with the potential to form G-quadruplexes were examined for their effects on a variety of replicative and translesion DNA polymerases from humans and lower organisms. Our results demonstrate that single-stranded templates containing four telomeric GGG runs fold into intramolecular G-quadruplex structures. These intramolecular G quadruplexes are somewhat dynamic in nature and stabilized by increasing KCl concentrations and decreasing temperatures. Furthermore, the presence of these intramolecular G-quadruplexes in the template dramatically inhibits DNA synthesis by various DNA polymerases, including the human polymerase δ employed during lagging strand replication of G-rich telomeric strands and several human translesion DNA polymerases potentially recruited to sites of replication blockage. Notably, misincorporation of nucleotides is observed when certain translesion polymerases are employed on substrates containing intramolecular G-quadruplexes, as is extension of the resulting mismatched base pairs upon dynamic unfolding of this secondary structure. These findings reveal the potential for blockage of DNA replication and genetic changes related to sequences capable of forming intramolecular G-quadruplexes.

The Genetics, Neurogenetics and Pharmacogenetics of Addiction.

Science.gov (United States)

Demers, Catherine H; Bogdan, Ryan; Agrawal, Arpana

2014-03-01

Addictions are prevalent psychiatric disorders that confer remarkable personal and social burden. Despite substantial evidence for their moderate, yet robust, heritability (approx. 50%), specific genetic mechanisms underlying their development and maintenance remain unclear. The goal of this selective review is to highlight progress in unveiling the genetic underpinnings of addiction. First, we revisit the basis for heritable variation in addiction before reviewing the most replicable candidate gene findings and emerging signals from genomewide association studies for alcohol, nicotine and cannabis addictions. Second, we survey the modest but growing field of neurogenetics examining how genetic variation influences corticostriatal structure, function, and connectivity to identify neural mechanisms that may underlie associations between genetic variation and addiction. Third, we outline how extant genomic findings are being used to develop and refine pharmacotherapies. Finally, as sample sizes for genetically informed studies of addiction approach critical mass, we posit five exciting possibilities that may propel further discovery (improved phenotyping, rare variant discovery, gene-environment interplay, epigenetics, and novel neuroimaging designs).

Mapping genetic variants associated with beta-adrenergic responses in inbred mice.

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Micha Hersch

Full Text Available β-blockers and β-agonists are primarily used to treat cardiovascular diseases. Inter-individual variability in response to both drug classes is well recognized, yet the identity and relative contribution of the genetic players involved are poorly understood. This work is the first genome-wide association study (GWAS addressing the values and susceptibility of cardiovascular-related traits to a selective β(1-blocker, Atenolol (ate, and a β-agonist, Isoproterenol (iso. The phenotypic dataset consisted of 27 highly heritable traits, each measured across 22 inbred mouse strains and four pharmacological conditions. The genotypic panel comprised 79922 informative SNPs of the mouse HapMap resource. Associations were mapped by Efficient Mixed Model Association (EMMA, a method that corrects for the population structure and genetic relatedness of the various strains. A total of 205 separate genome-wide scans were analyzed. The most significant hits include three candidate loci related to cardiac and body weight, three loci for electrocardiographic (ECG values, two loci for the susceptibility of atrial weight index to iso, four loci for the susceptibility of systolic blood pressure (SBP to perturbations of the β-adrenergic system, and one locus for the responsiveness of QTc (p<10(-8. An additional 60 loci were suggestive for one or the other of the 27 traits, while 46 others were suggestive for one or the other drug effects (p<10(-6. Most hits tagged unexpected regions, yet at least two loci for the susceptibility of SBP to β-adrenergic drugs pointed at members of the hypothalamic-pituitary-thyroid axis. Loci for cardiac-related traits were preferentially enriched in genes expressed in the heart, while 23% of the testable loci were replicated with datasets of the Mouse Phenome Database (MPD. Altogether these data and validation tests indicate that the mapped loci are relevant to the traits and responses studied.

Chromatin replication and histone dynamics

DEFF Research Database (Denmark)

Alabert, Constance; Jasencakova, Zuzana; Groth, Anja

2017-01-01

Inheritance of the DNA sequence and its proper organization into chromatin is fundamental for genome stability and function. Therefore, how specific chromatin structures are restored on newly synthesized DNA and transmitted through cell division remains a central question to understand cell fate...... choices and self-renewal. Propagation of genetic information and chromatin-based information in cycling cells entails genome-wide disruption and restoration of chromatin, coupled with faithful replication of DNA. In this chapter, we describe how cells duplicate the genome while maintaining its proper...... organization into chromatin. We reveal how specialized replication-coupled mechanisms rapidly assemble newly synthesized DNA into nucleosomes, while the complete restoration of chromatin organization including histone marks is a continuous process taking place throughout the cell cycle. Because failure...

Topology of a Membrane Associated Regulator of Prokaryotic DNA Replication

National Research Council Canada - National Science Library

Firshein, William

1998-01-01

This proposal has focused on a broad host range plasmid, RK2, as a model system to study how a pair of initiation proteins encoded by the plasmid for DNA replication function when replication occurs...

Chromatin Controls DNA Replication Origin Selection, Lagging-Strand Synthesis, and Replication Fork Rates.

Science.gov (United States)

Kurat, Christoph F; Yeeles, Joseph T P; Patel, Harshil; Early, Anne; Diffley, John F X

2017-01-05

The integrity of eukaryotic genomes requires rapid and regulated chromatin replication. How this is accomplished is still poorly understood. Using purified yeast replication proteins and fully chromatinized templates, we have reconstituted this process in vitro. We show that chromatin enforces DNA replication origin specificity by preventing non-specific MCM helicase loading. Helicase activation occurs efficiently in the context of chromatin, but subsequent replisome progression requires the histone chaperone FACT (facilitates chromatin transcription). The FACT-associated Nhp6 protein, the nucleosome remodelers INO80 or ISW1A, and the lysine acetyltransferases Gcn5 and Esa1 each contribute separately to maximum DNA synthesis rates. Chromatin promotes the regular priming of lagging-strand DNA synthesis by facilitating DNA polymerase α function at replication forks. Finally, nucleosomes disrupted during replication are efficiently re-assembled into regular arrays on nascent DNA. Our work defines the minimum requirements for chromatin replication in vitro and shows how multiple chromatin factors might modulate replication fork rates in vivo. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

The evolutionary ecology of molecular replicators.

Science.gov (United States)

Nee, Sean

2016-08-01

By reasonable criteria, life on the Earth consists mainly of molecular replicators. These include viruses, transposons, transpovirons, coviruses and many more, with continuous new discoveries like Sputnik Virophage. Their study is inherently multidisciplinary, spanning microbiology, genetics, immunology and evolutionary theory, and the current view is that taking a unified approach has great power and promise. We support this with a new, unified, model of their evolutionary ecology, using contemporary evolutionary theory coupling the Price equation with game theory, studying the consequences of the molecular replicators' promiscuous use of each others' gene products for their natural history and evolutionary ecology. Even at this simple expository level, we can make a firm prediction of a new class of replicators exploiting viruses such as lentiviruses like SIVs, a family which includes HIV: these have been explicitly stated in the primary literature to be non-existent. Closely connected to this departure is the view that multicellular organism immunology is more about the management of chronic infections rather than the elimination of acute ones and new understandings emerging are changing our view of the kind of theatre we ourselves provide for the evolutionary play of molecular replicators. This study adds molecular replicators to bacteria in the emerging field of sociomicrobiology.

Non-Equilibrium Thermodynamics of Self-Replicating Protocells

DEFF Research Database (Denmark)

Fellermann, Harold; Corominas-Murtra, Bernat; Hansen, Per Lyngs

2018-01-01

We provide a non-equilibrium thermodynamic description of the life-cycle of a droplet based, chemically feasible, system of protocells. By coupling the protocells metabolic kinetics with its thermodynamics, we demonstrate how the system can be driven out of equilibrium to ensure protocell growth...... and replication. This coupling allows us to derive the equations of evolution and to rigorously demonstrate how growth and replication life-cycle can be understood as a non-equilibrium thermodynamic cycle. The process does not appeal to genetic information or inheritance, and is based only on non......-equilibrium physics considerations. Our non-equilibrium thermodynamic description of simple, yet realistic, processes of protocell growth and replication, represents an advance in our physical understanding of a central biological phenomenon both in connection to the origin of life and for modern biology....

Moving into a new era of periodontal genetic studies: relevance of large case-control samples using severe phenotypes for genome-wide association studies.

Science.gov (United States)

Vaithilingam, R D; Safii, S H; Baharuddin, N A; Ng, C C; Cheong, S C; Bartold, P M; Schaefer, A S; Loos, B G

2014-12-01

Studies to elucidate the role of genetics as a risk factor for periodontal disease have gone through various phases. In the majority of cases, the initial 'hypothesis-dependent' candidate-gene polymorphism studies did not report valid genetic risk loci. Following a large-scale replication study, these initially positive results are believed to be caused by type 1 errors. However, susceptibility genes, such as CDKN2BAS (Cyclin Dependend KiNase 2B AntiSense RNA; alias ANRIL [ANtisense Rna In the Ink locus]), glycosyltransferase 6 domain containing 1 (GLT6D1) and cyclooxygenase 2 (COX2), have been reported as conclusive risk loci of periodontitis. The search for genetic risk factors accelerated with the advent of 'hypothesis-free' genome-wide association studies (GWAS). However, despite many different GWAS being performed for almost all human diseases, only three GWAS on periodontitis have been published - one reported genome-wide association of GLT6D1 with aggressive periodontitis (a severe phenotype of periodontitis), whereas the remaining two, which were performed on patients with chronic periodontitis, were not able to find significant associations. This review discusses the problems faced and the lessons learned from the search for genetic risk variants of periodontitis. Current and future strategies for identifying genetic variance in periodontitis, and the importance of planning a well-designed genetic study with large and sufficiently powered case-control samples of severe phenotypes, are also discussed. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Replication study for the association of 9 East Asian GWAS-derived loci with susceptibility to type 2 diabetes in a Japanese population.

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Kensuke Sakai

Full Text Available AIMS: East Asian genome-wide association studies (GWAS for type 2 diabetes identified 8 loci with genome-wide significance, and 2 loci with a borderline association. However, the associations of these loci except MAEA locus with type 2 diabetes have not been evaluated in independent East Asian cohorts. We performed a replication study to investigate the association of these susceptibility loci with type 2 diabetes in an independent Japanese population. METHODS: We genotyped 7,379 Japanese participants (5,315 type 2 diabetes and 2,064 controls for each of the 9 single nucleotide polymorphisms (SNPs, rs7041847 in GLIS3, rs6017317 in FITM2-R3HDML-HNF4A, rs6467136 near GCCI-PAX4, rs831571 near PSMD6, rs9470794 in ZFAND3, rs3786897 in PEPD, rs1535500 in KCNK16, rs16955379 in CMIP, and rs17797882 near WWOX. Because the sample size in this study was not sufficient to replicate single SNP associations, we constructed a genetic risk score (GRS by summing a number of risk alleles of the 9 SNPs, and examined the association of the GRS with type 2 diabetes using logistic regression analysis. RESULTS: With the exception of rs1535500 in KCNK16, all SNPs had the same direction of effect (odds ratio [OR]>1.0 as in the original reports. The GRS constructed from the 9 SNPs was significantly associated with type 2 diabetes in the Japanese population (p = 4.0 × 10(-4, OR = 1.05, 95% confidence interval: 1.02-1.09. In quantitative trait analyses, rs16955379 in CMIP was nominally associated with a decreased homeostasis model assessment of β-cell function and with increased fasting plasma glucose, but neither the individual SNPs nor the GRS showed a significant association with the glycemic traits. CONCLUSIONS: These results indicate that 9 loci that were identified in the East Asian GWAS meta-analysis have a significant effect on the susceptibility to type 2 diabetes in the Japanese population.

Epigenome-wide association study of fasting measures of glucose, insulin, and HOMA-IR in the Genetics of Lipid Lowering Drugs and Diet Network study.

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Hidalgo, Bertha; Irvin, M Ryan; Sha, Jin; Zhi, Degui; Aslibekyan, Stella; Absher, Devin; Tiwari, Hemant K; Kabagambe, Edmond K; Ordovas, Jose M; Arnett, Donna K

2014-02-01

Known genetic susceptibility loci for type 2 diabetes (T2D) explain only a small proportion of heritable T2D risk. We hypothesize that DNA methylation patterns may contribute to variation in diabetes-related risk factors, and this epigenetic variation across the genome can contribute to the missing heritability in T2D and related metabolic traits. We conducted an epigenome-wide association study for fasting glucose, insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) among 837 nondiabetic participants in the Genetics of Lipid Lowering Drugs and Diet Network study, divided into discovery (N = 544) and replication (N = 293) stages. Cytosine guanine dinucleotide (CpG) methylation at ∼470,000 CpG sites was assayed in CD4(+) T cells using the Illumina Infinium HumanMethylation 450 Beadchip. We fit a mixed model with the methylation status of each CpG as the dependent variable, adjusting for age, sex, study site, and T-cell purity as fixed-effects and family structure as a random-effect. A Bonferroni corrected P value of 1.1 × 10(-7) was considered significant in the discovery stage. Significant associations were tested in the replication stage using identical models. Methylation of a CpG site in ABCG1 on chromosome 21 was significantly associated with insulin (P = 1.83 × 10(-7)) and HOMA-IR (P = 1.60 × 10(-9)). Another site in the same gene was significant for HOMA-IR and of borderline significance for insulin (P = 1.29 × 10(-7) and P = 3.36 × 10(-6), respectively). Associations with the top two signals replicated for insulin and HOMA-IR (P = 5.75 × 10(-3) and P = 3.35 × 10(-2), respectively). Our findings suggest that methylation of a CpG site within ABCG1 is associated with fasting insulin and merits further evaluation as a novel disease risk marker.

Avian metapneumovirus M2:2 protein inhibits replication in Vero cells: modification facilitates live vaccine development.

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Clubbe, Jayne; Naylor, Clive J

2011-11-28

Throughout the world, avian metapneumovirus (AMPV) infection of subtype A is principally controlled by two live vaccines both derived from UK field strain #8544. Improvements of those vaccines by use of reverse genetics technology was found to be hampered by the inability of #8544 to replicate in the commonly exploited Vero cell based reverse genetics system. A systematic reverse genetics based genome modification of a DNA copy of #8544, employing sequence data from a Vero grown, #8544 derived, live vaccine; was used to determine mutations required to facilitate virus recovery and replication in Vero cells. This identified a single coding substitution in the M2:2 reading frame as responsible. Furthermore, ablation of M2:2 was found to elicit the same outcome. M2:2 sequence analysis of seven AMPVs found Vero cell adaption to be associated with non similar amino acid changes in M2:2. The study shows that M2:2 modification of field virus #8544 will enable research leading to improved vaccines. This may have more general application to other AMPV field strains. Copyright © 2011 Elsevier Ltd. All rights reserved.

Novel genetic loci associated with hippocampal volume.

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Hibar, Derrek P; Adams, Hieab H H; Jahanshad, Neda; Chauhan, Ganesh; Stein, Jason L; Hofer, Edith; Renteria, Miguel E; Bis, Joshua C; Arias-Vasquez, Alejandro; Ikram, M Kamran; Desrivières, Sylvane; Vernooij, Meike W; Abramovic, Lucija; Alhusaini, Saud; Amin, Najaf; Andersson, Micael; Arfanakis, Konstantinos; Aribisala, Benjamin S; Armstrong, Nicola J; Athanasiu, Lavinia; Axelsson, Tomas; Beecham, Ashley H; Beiser, Alexa; Bernard, Manon; Blanton, Susan H; Bohlken, Marc M; Boks, Marco P; Bralten, Janita; Brickman, Adam M; Carmichael, Owen; Chakravarty, M Mallar; Chen, Qiang; Ching, Christopher R K; Chouraki, Vincent; Cuellar-Partida, Gabriel; Crivello, Fabrice; Den Braber, Anouk; Doan, Nhat Trung; Ehrlich, Stefan; Giddaluru, Sudheer; Goldman, Aaron L; Gottesman, Rebecca F; Grimm, Oliver; Griswold, Michael E; Guadalupe, Tulio; Gutman, Boris A; Hass, Johanna; Haukvik, Unn K; Hoehn, David; Holmes, Avram J; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Jørgensen, Kjetil N; Karbalai, Nazanin; Kasperaviciute, Dalia; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H; Liewald, David C M; Lopez, Lorna M; Luciano, Michelle; Macare, Christine; Marquand, Andre F; Matarin, Mar; Mather, Karen A; Mattheisen, Manuel; McKay, David R; Milaneschi, Yuri; Muñoz Maniega, Susana; Nho, Kwangsik; Nugent, Allison C; Nyquist, Paul; Loohuis, Loes M Olde; Oosterlaan, Jaap; Papmeyer, Martina; Pirpamer, Lukas; Pütz, Benno; Ramasamy, Adaikalavan; Richards, Jennifer S; Risacher, Shannon L; Roiz-Santiañez, Roberto; Rommelse, Nanda; Ropele, Stefan; Rose, Emma J; Royle, Natalie A; Rundek, Tatjana; Sämann, Philipp G; Saremi, Arvin; Satizabal, Claudia L; Schmaal, Lianne; Schork, Andrew J; Shen, Li; Shin, Jean; Shumskaya, Elena; Smith, Albert V; Sprooten, Emma; Strike, Lachlan T; Teumer, Alexander; Tordesillas-Gutierrez, Diana; Toro, Roberto; Trabzuni, Daniah; Trompet, Stella; Vaidya, Dhananjay; Van der Grond, Jeroen; Van der Lee, Sven J; Van der Meer, Dennis; Van Donkelaar, Marjolein M J; Van Eijk, Kristel R; Van Erp, Theo G M; Van Rooij, Daan; Walton, Esther; Westlye, Lars T; Whelan, Christopher D; Windham, Beverly G; Winkler, Anderson M; Wittfeld, Katharina; Woldehawariat, Girma; Wolf, Christiane; Wolfers, Thomas; Yanek, Lisa R; Yang, Jingyun; Zijdenbos, Alex; Zwiers, Marcel P; Agartz, Ingrid; Almasy, Laura; Ames, David; Amouyel, Philippe; Andreassen, Ole A; Arepalli, Sampath; Assareh, Amelia A; Barral, Sandra; Bastin, Mark E; Becker, Diane M; Becker, James T; Bennett, David A; Blangero, John; van Bokhoven, Hans; Boomsma, Dorret I; Brodaty, Henry; Brouwer, Rachel M; Brunner, Han G; Buckner, Randy L; Buitelaar, Jan K; Bulayeva, Kazima B; Cahn, Wiepke; Calhoun, Vince D; Cannon, Dara M; Cavalleri, Gianpiero L; Cheng, Ching-Yu; Cichon, Sven; Cookson, Mark R; Corvin, Aiden; Crespo-Facorro, Benedicto; Curran, Joanne E; Czisch, Michael; Dale, Anders M; Davies, Gareth E; De Craen, Anton J M; De Geus, Eco J C; De Jager, Philip L; De Zubicaray, Greig I; Deary, Ian J; Debette, Stéphanie; DeCarli, Charles; Delanty, Norman; Depondt, Chantal; DeStefano, Anita; Dillman, Allissa; Djurovic, Srdjan; Donohoe, Gary; Drevets, Wayne C; Duggirala, Ravi; Dyer, Thomas D; Enzinger, Christian; Erk, Susanne; Espeseth, Thomas; Fedko, Iryna O; Fernández, Guillén; Ferrucci, Luigi; Fisher, Simon E; Fleischman, Debra A; Ford, Ian; Fornage, Myriam; Foroud, Tatiana M; Fox, Peter T; Francks, Clyde; Fukunaga, Masaki; Gibbs, J Raphael; Glahn, David C; Gollub, Randy L; Göring, Harald H H; Green, Robert C; Gruber, Oliver; Gudnason, Vilmundur; Guelfi, Sebastian; Håberg, Asta K; Hansell, Narelle K; Hardy, John; Hartman, Catharina A; Hashimoto, Ryota; Hegenscheid, Katrin; Heinz, Andreas; Le Hellard, Stephanie; Hernandez, Dena G; Heslenfeld, Dirk J; Ho, Beng-Choon; Hoekstra, Pieter J; Hoffmann, Wolfgang; Hofman, Albert; Holsboer, Florian; Homuth, Georg; Hosten, Norbert; Hottenga, Jouke-Jan; Huentelman, Matthew; Hulshoff Pol, Hilleke E; Ikeda, Masashi; Jack, Clifford R; Jenkinson, Mark; Johnson, Robert; Jönsson, Erik G; Jukema, J Wouter; Kahn, René S; Kanai, Ryota; Kloszewska, Iwona; Knopman, David S; Kochunov, Peter; Kwok, John B; Lawrie, Stephen M; Lemaître, Hervé; Liu, Xinmin; Longo, Dan L; Lopez, Oscar L; Lovestone, Simon; Martinez, Oliver; Martinot, Jean-Luc; Mattay, Venkata S; McDonald, Colm; McIntosh, Andrew M; McMahon, Francis J; McMahon, Katie L; Mecocci, Patrizia; Melle, Ingrid; Meyer-Lindenberg, Andreas; Mohnke, Sebastian; Montgomery, Grant W; Morris, Derek W; Mosley, Thomas H; Mühleisen, Thomas W; Müller-Myhsok, Bertram; Nalls, Michael A; Nauck, Matthias; Nichols, Thomas E; Niessen, Wiro J; Nöthen, Markus M; Nyberg, Lars; Ohi, Kazutaka; Olvera, Rene L; Ophoff, Roel A; Pandolfo, Massimo; Paus, Tomas; Pausova, Zdenka; Penninx, Brenda W J H; Pike, G Bruce; Potkin, Steven G; Psaty, Bruce M; Reppermund, Simone; Rietschel, Marcella; Roffman, Joshua L; Romanczuk-Seiferth, Nina; Rotter, Jerome I; Ryten, Mina; Sacco, Ralph L; Sachdev, Perminder S; Saykin, Andrew J; Schmidt, Reinhold; Schmidt, Helena; Schofield, Peter R; Sigursson, Sigurdur; Simmons, Andrew; Singleton, Andrew; Sisodiya, Sanjay M; Smith, Colin; Smoller, Jordan W; Soininen, Hilkka; Steen, Vidar M; Stott, David J; Sussmann, Jessika E; Thalamuthu, Anbupalam; Toga, Arthur W; Traynor, Bryan J; Troncoso, Juan; Tsolaki, Magda; Tzourio, Christophe; Uitterlinden, Andre G; Hernández, Maria C Valdés; Van der Brug, Marcel; van der Lugt, Aad; van der Wee, Nic J A; Van Haren, Neeltje E M; van 't Ent, Dennis; Van Tol, Marie-Jose; Vardarajan, Badri N; Vellas, Bruno; Veltman, Dick J; Völzke, Henry; Walter, Henrik; Wardlaw, Joanna M; Wassink, Thomas H; Weale, Michael E; Weinberger, Daniel R; Weiner, Michael W; Wen, Wei; Westman, Eric; White, Tonya; Wong, Tien Y; Wright, Clinton B; Zielke, Ronald H; Zonderman, Alan B; Martin, Nicholas G; Van Duijn, Cornelia M; Wright, Margaret J; Longstreth, W T; Schumann, Gunter; Grabe, Hans J; Franke, Barbara; Launer, Lenore J; Medland, Sarah E; Seshadri, Sudha; Thompson, Paul M; Ikram, M Arfan

2017-01-18

The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (r g =-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness.

Genome-wide association analyses identify 18 new loci associated with serum urate concentrations

NARCIS (Netherlands)

Kottgen, A.; Albrecht, E.; Teumer, A.; Vitart, V.; Krumsiek, J.; Hundertmark, C.; Pistis, G.; Ruggiero, D.; O'Seaghdha, C.M.; Haller, T.; Yang, Q.; Johnson, A.D.; Kutalik, Z.; Smith, A.V.; Shi, J.L.; Struchalin, M.; Middelberg, R.P.S.; Brown, M.J.; Gaffo, A.L.; Pirastu, N.; Li, G.; Hayward, C.; Zemunik, T.; Huffman, J.; Yengo, L.; Zhao, J.H.; Demirkan, A.; Feitosa, M.F.; Liu, X.; Malerba, G.; Lopez, L.M.; van der Harst, P.; Li, X.Z.; Kleber, M.E.; Hicks, A.A.; Nolte, I.M.; Johansson, A.; Murgia, F.; Wild, S.H.; Bakker, S.J.L.; Peden, J.F.; Dehghan, A.; Steri, M.; Tenesa, A.; Lagou, V.; Salo, P.; Mangino, M.; Rose, L.M.; Lehtimaki, T.; Woodward, O.M.; Okada, Y.; Tin, A.; Muller, C.; Oldmeadow, C.; Putku, M.; Czamara, D.; Kraft, P.; Frogheri, L.; Thun, G.A.; Grotevendt, A.; Gislason, G.K.; Harris, T.B.; Launer, L.J.; McArdle, P.; Shuldiner, A.R.; Boerwinkle, E.; Coresh, J.; Schmidt, H.; Schallert, M.; Martin, N.G.; Montgomery, G.W.; Kubo, M.; Nakamura, Y.; Tanaka, T.; Munroe, P.B.; Samani, N.J.; Jacobs, D.R.; Liu, K.; d'Adamo, P.; Ulivi, S.; Rotter, J.I.; Psaty, B.M.; Vollenweider, P.; Waeber, G.; Campbell, S.; Devuyst, O.; Navarro, P.; Kolcic, I.; Hastie, N.; Balkau, B.; Froguel, P.; Esko, T.; Salumets, A.; Khaw, K.T.; Langenberg, C.; Wareham, N.J.; Isaacs, A.; Kraja, A.; Zhang, Q.Y.; Penninx, B.W.J.H.; Smit, J.H.; Bochud, M.; Gieger, C.

2013-01-01

Elevated serum urate concentrations can cause gout, a prevalent and painful inflammatory arthritis. By combining data from >140,000 individuals of European ancestry within the Global Urate Genetics Consortium (GUGC), we identified and replicated 28 genome-wide significant loci in association with

Genome-wide association analyses identify 18 new loci associated with serum urate concentrations

NARCIS (Netherlands)

Köttgen, Anna; Albrecht, Eva; Teumer, Alexander; Vitart, Veronique; Krumsiek, Jan; Hundertmark, Claudia; Pistis, Giorgio; Ruggiero, Daniela; O'Seaghdha, Conall M; Haller, Toomas; Yang, Qiong; Tanaka, Toshiko; Johnson, Andrew D; Kutalik, Zoltán; Smith, Albert V; Shi, Julia; Struchalin, Maksim; Middelberg, Rita P S; Brown, Morris J; Gaffo, Angelo L; Pirastu, Nicola; Li, Guo; Hayward, Caroline; Zemunik, Tatijana; Huffman, Jennifer; Yengo, Loic; Zhao, Jing Hua; Demirkan, Ayse; Feitosa, Mary F; Liu, Xuan; Malerba, Giovanni; Lopez, Lorna M; van der Harst, Pim; Li, Xinzhong; Kleber, Marcus E; Hicks, Andrew A; Nolte, Ilja M; Johansson, Asa; Murgia, Federico; Bakker, Stephan J L; Lagou, Vasiliki; Bruinenberg, Marcel; Stolk, Ronald P; Penninx, Brenda W; Mateo Leach, Irene; van Gilst, Wiek H; Hillege, Hans L; Wolffenbuttel, Bruce H R; Snieder, Harold; Navis, Gerjan

Elevated serum urate concentrations can cause gout, a prevalent and painful inflammatory arthritis. By combining data from >140,000 individuals of European ancestry within the Global Urate Genetics Consortium (GUGC), we identified and replicated 28 genome-wide significant loci in association with

Genetic Risk Score for Essential Hypertension and Risk of Preeclampsia.

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Smith, Caitlin J; Saftlas, Audrey F; Spracklen, Cassandra N; Triche, Elizabeth W; Bjonnes, Andrew; Keating, Brendan; Saxena, Richa; Breheny, Patrick J; Dewan, Andrew T; Robinson, Jennifer G; Hoh, Josephine; Ryckman, Kelli K

2016-01-01

Preeclampsia is a hypertensive complication of pregnancy characterized by novel onset of hypertension after 20 weeks gestation, accompanied by proteinuria. Epidemiological evidence suggests that genetic susceptibility exists for preeclampsia; however, whether preeclampsia is the result of underlying genetic risk for essential hypertension has yet to be investigated. Based on the hypertensive state that is characteristic of preeclampsia, we aimed to determine if established genetic risk scores (GRSs) for hypertension and blood pressure are associated with preeclampsia. Subjects consisted of 162 preeclamptic cases and 108 normotensive pregnant controls, all of Iowa residence. Subjects' DNA was extracted from buccal swab samples and genotyped on the Affymetrix Genome-wide Human SNP Array 6.0 (Affymetrix, Santa Clara, CA). Missing genotypes were imputed using MaCH and Minimac software. GRSs were calculated for hypertension, systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) using established genetic risk loci for each outcome. Regression analyses were performed to determine the association between GRS and risk of preeclampsia. These analyses were replicated in an independent US population of 516 cases and 1,097 controls of European ancestry. GRSs for hypertension, SBP, DBP, and MAP were not significantly associated with risk for preeclampsia (P > 0.189). The results of the replication analysis also yielded nonsignificant associations. GRSs for hypertension and blood pressure are not associated with preeclampsia, suggesting that an underlying predisposition to essential hypertension is not on the causal pathway of preeclampsia. © American Journal of Hypertension, Ltd 2015. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

In Situ Tagged nsp15 Reveals Interactions with Coronavirus Replication/Transcription Complex-Associated Proteins

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Jeremiah Athmer

2017-01-01

Full Text Available Coronavirus (CoV replication and transcription are carried out in close proximity to restructured endoplasmic reticulum (ER membranes in replication/transcription complexes (RTC. Many of the CoV nonstructural proteins (nsps are required for RTC function; however, not all of their functions are known. nsp15 contains an endoribonuclease domain that is conserved in the CoV family. While the enzymatic activity and crystal structure of nsp15 are well defined, its role in replication remains elusive. nsp15 localizes to sites of RNA replication, but whether it acts independently or requires additional interactions for its function remains unknown. To begin to address these questions, we created an in situ tagged form of nsp15 using the prototypic CoV, mouse hepatitis virus (MHV. In MHV, nsp15 contains the genomic RNA packaging signal (P/S, a 95-bp RNA stem-loop structure that is not required for viral replication or nsp15 function. Utilizing this knowledge, we constructed an internal hemagglutinin (HA tag that replaced the P/S. We found that nsp15-HA was localized to discrete perinuclear puncta and strongly colocalized with nsp8 and nsp12, both well-defined members of the RTC, but not the membrane (M protein, involved in virus assembly. Finally, we found that nsp15 interacted with RTC-associated proteins nsp8 and nsp12 during infection, and this interaction was RNA independent. From this, we conclude that nsp15 localizes and interacts with CoV proteins in the RTC, suggesting it plays a direct or indirect role in virus replication. Furthermore, the use of in situ epitope tags could be used to determine novel nsp-nsp interactions in coronaviruses.

Adenovirus-encoding virus-associated RNAs suppress HDGF gene expression to support efficient viral replication.

Directory of Open Access Journals (Sweden)

Saki Kondo

Full Text Available Non-coding small RNAs are involved in many physiological responses including viral life cycles. Adenovirus-encoding small RNAs, known as virus-associated RNAs (VA RNAs, are transcribed throughout the replication process in the host cells, and their transcript levels depend on the copy numbers of the viral genome. Therefore, VA RNAs are abundant in infected cells after genome replication, i.e. during the late phase of viral infection. Their function during the late phase is the inhibition of interferon-inducible protein kinase R (PKR activity to prevent antiviral responses; recently, mivaRNAs, the microRNAs processed from VA RNAs, have been reported to inhibit cellular gene expression. Although VA RNA transcription starts during the early phase, little is known about its function. The reason may be because much smaller amount of VA RNAs are transcribed during the early phase than the late phase. In this study, we applied replication-deficient adenovirus vectors (AdVs and novel AdVs lacking VA RNA genes to analyze the expression changes in cellular genes mediated by VA RNAs using microarray analysis. AdVs are suitable to examine the function of VA RNAs during the early phase, since they constitutively express VA RNAs but do not replicate except in 293 cells. We found that the expression level of hepatoma-derived growth factor (HDGF significantly decreased in response to the VA RNAs under replication-deficient condition, and this suppression was also observed during the early phase under replication-competent conditions. The suppression was independent of mivaRNA-induced downregulation, suggesting that the function of VA RNAs during the early phase differs from that during the late phase. Notably, overexpression of HDGF inhibited AdV growth. This is the first report to show the function, in part, of VA RNAs during the early phase that may be contribute to efficient viral growth.

Pitfalls in setting up genetic studies on preeclampsia.

Science.gov (United States)

Laivuori, Hannele

2013-04-01

This presentation will consider approaches to discover susceptibility genes for a complex genetic disorder such as preeclampsia. The clinical disease presumably results from the additive effects of multiple sequence variants from the mother and the foetus together with environmental factors. Disease heterogeneity and underpowered study designs are likely to be behind non-reproducible results in candidate gene association studies. To avoid spurious findings, sample size and characteristics of the study populations as well as replication studies in an independent study population should be an essential part of a study design. In family-based linkage studies relationship with genotype and phenotype may be modified by a variety of factors. The large number of families needed in discovering genetic variants with modest effect sizes is difficult to attain. Moreover, the identification of underlying mutations has proven difficult. When pooling data or performing meta-analyses from different populations, disease and locus heterogeneity may become a major issue. First genome-wide association studies (GWAS) have identified risk loci for preeclampsia. Adequately powered replication studies are critical in order to replicate the initial GWAS findings. This approach requires rigorous multiple testing correction. The expected effect sizes of individual sequence variants on preeclampsia are small, but this approach is likely to decipher new clues to the pathogenesis. The rare variants, gene-gene and gene-environmental interactions as well as noncoding genetic variations and epigenetics are expected to explain the missing heritability. Next-generation sequencing technologies will make large amount of data on genomes and transcriptomes available. Complexity of the data poses a challenge. Different depths of coverage might be chosen depending on the design of the study, and validation of the results by different methods is mandatory. In order to minimize disease heterogeneity in

Genetic mutations associated with status epilepticus.

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Bhatnagar, M; Shorvon, S

2015-08-01

This paper reports the results of a preliminary search of the literature aimed at identifying the genetic mutations reported to be strongly associated with status epilepticus. Genetic mutations were selected for inclusion if status epilepticus was specifically mentioned as a consequence of the mutation in standard genetic databases or in a case report or review article. Mutations in 122 genes were identified. The genetic mutations identified were found in only rare conditions (sometimes vanishingly rare) and mostly in infants and young children with multiple other handicaps. Most of the genetic mutations can be subdivided into those associated with cortical dysplasias, inborn errors of metabolism, mitochondrial disease, or epileptic encephalopathies and childhood syndromes. There are no identified 'pure status epilepticus genes'. The range of genes underpinning status epilepticus differs in many ways from the range of genes underpinning epilepsy, which suggests that the processes underpinning status epilepticus differ from those underpinning epilepsy. It has been frequently postulated that status epilepticus is the result of a failure of 'seizure termination mechanisms', but the wide variety of genes affecting very diverse biochemical pathways identified in this survey makes any unitary cause unlikely. The genetic influences in status epilepticus are likely to involve a wide range of mechanisms, some related to development, some to cerebral energy production, some to diverse altered biochemical pathways, some to transmitter and membrane function, and some to defects in networks or systems. The fact that many of the identified genes are involved with cerebral development suggests that status epilepticus might often be a system or network phenomenon. To date, there are very few genes identified which are associated with adult-onset status epilepticus (except in those with preexisting neurological damage), and this is disappointing as the cause of many adult

Genetic Aspects of Alzheimer Disease

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Williamson, Jennifer; Goldman, Jill; Marder, Karen S.

2011-01-01

Background Alzheimer disease (AD) is a genetically complex disorder. Mutations in 3 genes, presenilin 1, amyloid precursor protein, and presenilin 2, lead to early-onset familial AD in rare families with onset of disease occurring prior to age 65. Specific polymorphisms in apolipoprotein E are associated with the more common, late-onset AD occurring after age 65. In this review, we discuss current advances in AD genetics, the implications of the known AD genes, presenilin 1, presenilin 2, amyloid precursor protein, and apolipoprotein E, and other possible genes on the clinical diagnosis, treatment, and genetic counseling of patients and families with early- and late-onset AD. Review Summary In addition to the mutations in 4 known genes associated with AD, mutations in other genes may be implicated in the pathogenesis of the disease. Most recently, 2 different research groups have reported genetic association between 2 genes, sortilin-related receptor and GAB2, and AD. These associations have not changed the diagnostic and medical management of AD. Conclusions New research in the genetics of AD have implicated novel genes as having a role in the disease, but these findings have not been replicated nor have specific disease causing mutations been identified. To date, clinical genetic testing is limited to familial early-onset disease for symptomatic individuals and asymptomatic relatives and, although not recommended, amyloid precursor protein apolipoprotein E testing as an adjunct to diagnosis of symptomatic individuals. PMID:19276785

Association of Genetic Variants With Response to Anti-Vascular Endothelial Growth Factor Therapy in Age-Related Macular Degeneration.

Science.gov (United States)

Lorés-Motta, Laura; Riaz, Moeen; Grunin, Michelle; Corominas, Jordi; van Asten, Freekje; Pauper, Marc; Leenders, Mathieu; Richardson, Andrea J; Muether, Philipp; Cree, Angela J; Griffiths, Helen L; Pham, Connie; Belanger, Marie-Claude; Meester-Smoor, Magda A; Ali, Manir; Heid, Iris M; Fritsche, Lars G; Chakravarthy, Usha; Gale, Richard; McKibbin, Martin; Inglehearn, Chris F; Schlingemann, Reinier O; Omar, Amer; Chen, John; Koenekoop, Robert K; Fauser, Sascha; Guymer, Robyn H; Hoyng, Carel B; de Jong, Eiko K; Lotery, Andrew J; Mitchell, Paul; den Hollander, Anneke I; Baird, Paul N; Chowers, Itay

2018-05-31

Visual acuity (VA) outcomes differ considerably among patients with neovascular age-related macular degeneration (nAMD) treated with anti-vascular endothelial growth factor (VEGF) drugs. Identification of pharmacogenetic associations may help clinicians understand the mechanisms underlying this variability as well as pave the way for personalized treatment in nAMD. To identify genetic factors associated with variability in the response to anti-VEGF therapy for patients with nAMD. In this multicenter genome-wide association study, 678 patients with nAMD with genome-wide genotyping data were included in the discovery phase; 1380 additional patients with nAMD were genotyped for selected common variants in the replication phase. All participants received 3 monthly injections of bevacizumab or ranibizumab. Clinical data were evaluated for inclusion/exclusion criteria from October 2014 to October 2015, followed by data analysis from October 2015 to February 2016. For replication cohort genotyping, clinical data collection and analysis (including meta-analysis) was performed from March 2016 to April 2017. Change in VA after the loading dose of 3 monthly anti-VEGF injections compared with baseline. Of the 2058 included patients, 1210 (58.8%) were women, and the mean (SD) age across all cohorts was 78 (7.4) years. Patients included in the discovery cohort and most of the patients in the replication cohorts were of European descent. The mean (SD) baseline VA was 51.3 (20.3) Early Treatment Diabetic Retinopathy Study (ETDRS) score letters, and the mean (SD) change in VA after the loading dose of 3 monthly injections was a gain of 5.1 (13.9) ETDRS score letters (ie, 1-line gain). Genome-wide single-variant analyses of common variants revealed 5 independent loci that reached a P value less than 10 × 10-5. After replication and meta-analysis of the lead variants, rs12138564 located in the CCT3 gene remained nominally associated with a better treatment outcome (ETDRS letter

Genetic association between Interleukin-17A gene polymorphisms and the pathogenesis of Graves' disease in the Han Chinese population.

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Qi, Yicheng; Zheng, Huan; Liu, Nan; Guo, Ting; Zhu, Wei; Wang, Shu; Cui, Bin; Ning, Guang

2015-01-19

Graves' disease, one of the commonest autoimmune disorders, has a complex genetic basis. Interleukin-17A (IL-17A) is an important cytokine involved in innate and adaptive immune responses. This case-control study sought to investigate genetic association between the IL-17A gene and the process of Graves' disease (GD). Our pilot study was performed on a cohort from Shanghai, which included 713 patients with GD and 756 healthy controls. A replicate cohort was from Xiamen, recruiting 444 patients with GD and 427 healthy subjects. Six single nucleotide polymorphisms (SNPs) (rs4711998, rs3819024, rs2275913, rs8193037, rs3819025 and rs3748067) within the IL-17A gene were genotyped by the SNPstream Genotyping Systems and Taqman PCR method. In Shanghai cohorts, the frequencies of rs8193037 alleles were strongly different between patients with Graves' disease (G, 87·6% and A, 12·4%) and healthy controls (G, 91·4% and A, 8·6%) (P = 0·00067). The A carriers were associated with increased Graves' disease risks when compared with the G carriers (OR = 1·51, 95%CI = 1·19-1·92). In replicate cohorts, the proportion of individuals carrying the A allele of rs8193037 was significantly higher in patients with Graves' disease than in controls [Graves' disease vs control, 14·3% vs 9·1%, OR = 1·66 (95% CI: 1·23-2·24), P allele  = 0·0082]. In addition, rs8193037 and rs3748067 were found to be different in both genotype and allele distributions in Graves' disease-associated ophthalmopathy patients and controls in Shanghai cohorts. Haplotype association analysis also identified five main haplotypes of those six SNPs. These results suggested that the polymorphism of IL-17A rs8193037 was strongly associated with Graves' disease susceptibility in the Chinese Han population.z. © 2015 John Wiley & Sons Ltd.

Genetic polymorphisms associated with breast cancer in malaysian cohort.

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Chahil, Jagdish Kaur; Munretnam, Khamsigan; Samsudin, Nurulhafizah; Lye, Say Hean; Hashim, Nikman Adli Nor; Ramzi, Nurul Hanis; Velapasamy, Sharmila; Wee, Ler Lian; Alex, Livy

2015-04-01

Genome-wide association studies have discovered multiple single nucleotide polymorphisms (SNPs) associated with the risk of common diseases. The objective of this study was to demonstrate the replication of previously published SNPs that showed statistical significance for breast cancer in the Malaysian population. In this case-control study, 80 subjects for each group were recruited from various hospitals in Malaysia. A total of 768 SNPs were genotyped and analyzed to distinguish risk and protective alleles. A total of three SNPs were found to be associated with increased risk of breast cancer while six SNPs showed protective effect. All nine were statistically significant SNPs (p ≤ 0.01), five SNPs from previous studies were successfully replicated in our study. Significant modifiable (diet) and non-modifiable (family history of breast cancer in first degree relative) risk factors were also observed. We identified nine SNPs from this study to be either conferring susceptibility or protection to breast cancer which may serve as potential markers in risk prediction.

Slow Replication Fork Velocity of Homologous Recombination-Defective Cells Results from Endogenous Oxidative Stress

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Magdalou, Indiana; Machon, Christelle; Dardillac, Elodie; Técher, Hervé; Guitton, Jérôme; Debatisse, Michelle; Lopez, Bernard S.

2016-01-01

Replications forks are routinely hindered by different endogenous stresses. Because homologous recombination plays a pivotal role in the reactivation of arrested replication forks, defects in homologous recombination reveal the initial endogenous stress(es). Homologous recombination-defective cells consistently exhibit a spontaneously reduced replication speed, leading to mitotic extra centrosomes. Here, we identify oxidative stress as a major endogenous source of replication speed deceleration in homologous recombination-defective cells. The treatment of homologous recombination-defective cells with the antioxidant N-acetyl-cysteine or the maintenance of the cells at low O2 levels (3%) rescues both the replication fork speed, as monitored by single-molecule analysis (molecular combing), and the associated mitotic extra centrosome frequency. Reciprocally, the exposure of wild-type cells to H2O2 reduces the replication fork speed and generates mitotic extra centrosomes. Supplying deoxynucleotide precursors to H2O2-exposed cells rescued the replication speed. Remarkably, treatment with N-acetyl-cysteine strongly expanded the nucleotide pool, accounting for the replication speed rescue. Remarkably, homologous recombination-defective cells exhibit a high level of endogenous reactive oxygen species. Consistently, homologous recombination-defective cells accumulate spontaneous γH2AX or XRCC1 foci that are abolished by treatment with N-acetyl-cysteine or maintenance at 3% O2. Finally, oxidative stress stimulated homologous recombination, which is suppressed by supplying deoxynucleotide precursors. Therefore, the cellular redox status strongly impacts genome duplication and transmission. Oxidative stress should generate replication stress through different mechanisms, including DNA damage and nucleotide pool imbalance. These data highlight the intricacy of endogenous replication and oxidative stresses, which are both evoked during tumorigenesis and senescence initiation

Slow Replication Fork Velocity of Homologous Recombination-Defective Cells Results from Endogenous Oxidative Stress.

Directory of Open Access Journals (Sweden)

Therese Wilhelm

2016-05-01

Full Text Available Replications forks are routinely hindered by different endogenous stresses. Because homologous recombination plays a pivotal role in the reactivation of arrested replication forks, defects in homologous recombination reveal the initial endogenous stress(es. Homologous recombination-defective cells consistently exhibit a spontaneously reduced replication speed, leading to mitotic extra centrosomes. Here, we identify oxidative stress as a major endogenous source of replication speed deceleration in homologous recombination-defective cells. The treatment of homologous recombination-defective cells with the antioxidant N-acetyl-cysteine or the maintenance of the cells at low O2 levels (3% rescues both the replication fork speed, as monitored by single-molecule analysis (molecular combing, and the associated mitotic extra centrosome frequency. Reciprocally, the exposure of wild-type cells to H2O2 reduces the replication fork speed and generates mitotic extra centrosomes. Supplying deoxynucleotide precursors to H2O2-exposed cells rescued the replication speed. Remarkably, treatment with N-acetyl-cysteine strongly expanded the nucleotide pool, accounting for the replication speed rescue. Remarkably, homologous recombination-defective cells exhibit a high level of endogenous reactive oxygen species. Consistently, homologous recombination-defective cells accumulate spontaneous γH2AX or XRCC1 foci that are abolished by treatment with N-acetyl-cysteine or maintenance at 3% O2. Finally, oxidative stress stimulated homologous recombination, which is suppressed by supplying deoxynucleotide precursors. Therefore, the cellular redox status strongly impacts genome duplication and transmission. Oxidative stress should generate replication stress through different mechanisms, including DNA damage and nucleotide pool imbalance. These data highlight the intricacy of endogenous replication and oxidative stresses, which are both evoked during tumorigenesis and

Slow Replication Fork Velocity of Homologous Recombination-Defective Cells Results from Endogenous Oxidative Stress.

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Wilhelm, Therese; Ragu, Sandrine; Magdalou, Indiana; Machon, Christelle; Dardillac, Elodie; Técher, Hervé; Guitton, Jérôme; Debatisse, Michelle; Lopez, Bernard S

2016-05-01

Replications forks are routinely hindered by different endogenous stresses. Because homologous recombination plays a pivotal role in the reactivation of arrested replication forks, defects in homologous recombination reveal the initial endogenous stress(es). Homologous recombination-defective cells consistently exhibit a spontaneously reduced replication speed, leading to mitotic extra centrosomes. Here, we identify oxidative stress as a major endogenous source of replication speed deceleration in homologous recombination-defective cells. The treatment of homologous recombination-defective cells with the antioxidant N-acetyl-cysteine or the maintenance of the cells at low O2 levels (3%) rescues both the replication fork speed, as monitored by single-molecule analysis (molecular combing), and the associated mitotic extra centrosome frequency. Reciprocally, the exposure of wild-type cells to H2O2 reduces the replication fork speed and generates mitotic extra centrosomes. Supplying deoxynucleotide precursors to H2O2-exposed cells rescued the replication speed. Remarkably, treatment with N-acetyl-cysteine strongly expanded the nucleotide pool, accounting for the replication speed rescue. Remarkably, homologous recombination-defective cells exhibit a high level of endogenous reactive oxygen species. Consistently, homologous recombination-defective cells accumulate spontaneous γH2AX or XRCC1 foci that are abolished by treatment with N-acetyl-cysteine or maintenance at 3% O2. Finally, oxidative stress stimulated homologous recombination, which is suppressed by supplying deoxynucleotide precursors. Therefore, the cellular redox status strongly impacts genome duplication and transmission. Oxidative stress should generate replication stress through different mechanisms, including DNA damage and nucleotide pool imbalance. These data highlight the intricacy of endogenous replication and oxidative stresses, which are both evoked during tumorigenesis and senescence initiation

Intrapulmonary Human Cytomegalovirus Replication in Lung Transplant Recipients Is Associated With a Rise of CCL-18 and CCL-20 Chemokine Levels.

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Weseslindtner, Lukas; Görzer, Irene; Roedl, Kevin; Küng, Erik; Jaksch, Peter; Klepetko, Walter; Puchhammer-Stöckl, Elisabeth

2017-01-01

In lung transplant recipients (LTRs), human cytomegalovirus (HCMV) DNA detection in the bronchoalveolar lavage fluid (BALF) indicates HCMV replication in the pulmonary compartment. Such local HCMV replication episodes may remain asymptomatic or may lead to symptomatic HCMV disease. Here, we investigated LTRs with intrapulmonary HCMV replication for the chemokines CCL-18 and CCL-20. In particular, we analyzed whether these chemokines rise in the allograft and/or the blood and are associated with HCMV disease. CCL-18 and CCL-20 levels were quantitated by ELISA in BALF and serum samples from 60 LTRs. During the posttransplant follow-up, these LTRs displayed HCMV DNA detection in the BALF by PCR, whereas other infectious agents were undetectable. Furthermore, we investigated samples from 10 controls who did not display any HCMV replication episode during the follow-up. HCMV replication in the allograft was associated with a significant increase of CCL-18 and CCL-20 BALF levels (P Wilcoxon signed-rank test) and a significant rise of CCL-20 (P Wilcoxon signed-rank test) but not of CCL-18 in the blood. In controls, no such chemokine increase was observed. Furthermore, CCL-18 BALF levels were significantly higher in 8 LTRs who additionally developed HCMV disease, as compared with the other 52 patients in whom HCMV replication remained asymptomatic (P test). HCMV replication in the allograft causes an intrapulmonary increase of CCL-18 and CCL-20 and a systemic rise of CCL-20 serum levels. Strong intrapulmonary CCL-18 responses are associated with symptomatic HCMV disease, proposing that CCL-18 BALF levels could serve as a marker.

DNA replication restart and cellular dynamics of Hef helicase/nuclease protein in Haloferax volcanii.

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Lestini, Roxane; Delpech, Floriane; Myllykallio, Hannu

2015-11-01

Understanding how frequently spontaneous replication arrests occur and how archaea deal with these arrests are very interesting and challenging research topics. Here we will described how genetic and imaging studies have revealed the central role of the archaeal helicase/nuclease Hef belonging to the XPF/MUS81/FANCM family of endonucleases in repair of arrested replication forks. Special focus will be on description of a recently developed combination of genetic and imaging tools to study the dynamic localization of a functional Hef::GFP (Green Fluorescent Protein) fusion protein in the living cells of halophilic archaea Haloferax volcanii. As Archaea provide an excellent and unique model for understanding how DNA replication is regulated to allow replication of a circular DNA molecule either from single or multiple replication origins, we will also summarize recent studies that have revealed peculiar features regarding DNA replication, particularly in halophilic archaea. We strongly believe that fundamental knowledge of our on-going studies will shed light on the evolutionary history of the DNA replication machinery and will help to establish general rules concerning replication restart and the key role of recombination proteins not only in bacteria, yeast and higher eukaryotes but also in archaea. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

No Reliable Association between Runs of Homozygosity and Schizophrenia in a Well-Powered Replication Study

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Bjelland, Douglas W.; Howrigan, Daniel P.; Abdellaoui, Abdel; Breen, Gerome; Borglum, Anders; Cichon, Sven; Degenhardt, Franziska; Forstner, Andreas J.; Genovese, Giulio; Heilmann-Heimbach, Stefanie; Hoffman, Per; Maier, Wolfgang; Mattheisen, Manuel; Morris, Derek; Mowry, Bryan; Müller-Mhysok, Betram; Neale, Benjamin; Nenadic, Igor; Nöthen, Markus M.; O’Dushlaine, Colm; Rietschel, Marcella; Ruderfer, Douglas M.; Rujescu, Dan; Schulze, Thomas G.; Simonson, Matthew A.; Stahl, Eli; Strohmaier, Jana; Sullivan, Patrick F.; Keller, Matthew C.

2016-01-01

It is well known that inbreeding increases the risk of recessive monogenic diseases, but it is less certain whether it contributes to the etiology of complex diseases such as schizophrenia. One way to estimate the effects of inbreeding is to examine the association between disease diagnosis and genome-wide autozygosity estimated using runs of homozygosity (ROH) in genome-wide single nucleotide polymorphism arrays. Using data for schizophrenia from the Psychiatric Genomics Consortium (n = 21,868), Keller et al. (2012) estimated that the odds of developing schizophrenia increased by approximately 17% for every additional percent of the genome that is autozygous (β = 16.1, CI(β) = [6.93, 25.7], Z = 3.44, p = 0.0006). Here we describe replication results from 22 independent schizophrenia case-control datasets from the Psychiatric Genomics Consortium (n = 39,830). Using the same ROH calling thresholds and procedures as Keller et al. (2012), we were unable to replicate the significant association between ROH burden and schizophrenia in the independent PGC phase II data, although the effect was in the predicted direction, and the combined (original + replication) dataset yielded an attenuated but significant relationship between Froh and schizophrenia (β = 4.86,CI(β) = [0.90,8.83],Z = 2.40,p = 0.02). Since Keller et al. (2012), several studies reported inconsistent association of ROH burden with complex traits, particularly in case-control data. These conflicting results might suggest that the effects of autozygosity are confounded by various factors, such as socioeconomic status, education, urbanicity, and religiosity, which may be associated with both real inbreeding and the outcome measures of interest. PMID:27792727

Genetic and clinic predictors of new onset diabetes mellitus after transplantation.

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Saigi-Morgui, Núria; Quteineh, Lina; Bochud, Pierre-Yves; Crettol, Severine; Kutalik, Zoltán; Mueller, Nicolas J; Binet, Isabelle; Van Delden, Christian; Steiger, Jürg; Mohacsi, Paul; Dufour, Jean-Francois; Soccal, Paola M; Pascual, Manuel; Eap, Chin B

2017-12-27

New Onset Diabetes after Transplantation (NODAT) is a frequent complication after solid organ transplantation, with higher incidence during the first year. Several clinical and genetic factors have been described as risk factors of Type 2 Diabetes (T2DM). Additionally, T2DM shares some genetic factors with NODAT. We investigated if three genetic risk scores (w-GRS) and clinical factors were associated with NODAT and how they predicted NODAT development 1 year after transplantation. In both main (n = 725) and replication (n = 156) samples the clinical risk score was significantly associated with NODAT (OR main : 1.60 [1.36-1.90], p = 3.72*10 -8 and OR replication : 2.14 [1.39-3.41], p = 0.0008, respectively). Two w-GRS were significantly associated with NODAT in the main sample (OR w-GRS 2 :1.09 [1.04-1.15], p = 0.001 and OR w-GRS 3 :1.14 [1.01-1.29], p = 0.03) and a similar OR w-GRS 2 was found in the replication sample, although it did not reach significance probably due to a power issue. Despite the low OR of w-GRS on NODAT compared to clinical covariates, when integrating w-GRS 2 and w-GRS 3 in the clinical model, the Area under the Receiver Operating Characteristics curve (AUROC), specificity, sensitivity and accuracy were 0.69, 0.71, 0.58 and 0.68, respectively, with significant Likelihood Ratio test discrimination index (p-value 0.0004), performing better in NODAT discrimination than the clinical model alone. Twenty-five patients needed to be genotyped in order to detect one misclassified case that would have developed NODAT 1 year after transplantation if using only clinical covariates. To our knowledge, this is the first study extensively examining genetic risk scores contributing to NODAT development.

Pooled genome wide association detects association upstream of FCRL3 with Graves' disease.

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Khong, Jwu Jin; Burdon, Kathryn P; Lu, Yi; Laurie, Kate; Leonardos, Lefta; Baird, Paul N; Sahebjada, Srujana; Walsh, John P; Gajdatsy, Adam; Ebeling, Peter R; Hamblin, Peter Shane; Wong, Rosemary; Forehan, Simon P; Fourlanos, Spiros; Roberts, Anthony P; Doogue, Matthew; Selva, Dinesh; Montgomery, Grant W; Macgregor, Stuart; Craig, Jamie E

2016-11-18

Graves' disease is an autoimmune thyroid disease of complex inheritance. Multiple genetic susceptibility loci are thought to be involved in Graves' disease and it is therefore likely that these can be identified by genome wide association studies. This study aimed to determine if a genome wide association study, using a pooling methodology, could detect genomic loci associated with Graves' disease. Nineteen of the top ranking single nucleotide polymorphisms including HLA-DQA1 and C6orf10, were clustered within the Major Histo-compatibility Complex region on chromosome 6p21, with rs1613056 reaching genome wide significance (p = 5 × 10 -8 ). Technical validation of top ranking non-Major Histo-compatablity complex single nucleotide polymorphisms with individual genotyping in the discovery cohort revealed four single nucleotide polymorphisms with p ≤ 10 -4 . Rs17676303 on chromosome 1q23.1, located upstream of FCRL3, showed evidence of association with Graves' disease across the discovery, replication and combined cohorts. A second single nucleotide polymorphism rs9644119 downstream of DPYSL2 showed some evidence of association supported by finding in the replication cohort that warrants further study. Pooled genome wide association study identified a genetic variant upstream of FCRL3 as a susceptibility locus for Graves' disease in addition to those identified in the Major Histo-compatibility Complex. A second locus downstream of DPYSL2 is potentially a novel genetic variant in Graves' disease that requires further confirmation.

Human Parvovirus B19 Utilizes Cellular DNA Replication Machinery for Viral DNA Replication.

Science.gov (United States)

Zou, Wei; Wang, Zekun; Xiong, Min; Chen, Aaron Yun; Xu, Peng; Ganaie, Safder S; Badawi, Yomna; Kleiboeker, Steve; Nishimune, Hiroshi; Ye, Shui Qing; Qiu, Jianming

2018-03-01

associated with the replicating single-stranded DNA viral genome and played a critical role in viral DNA replication. In contrast, the DNA damage response-induced phosphorylated forms of RPA32 were dispensable for viral DNA replication. Copyright © 2018 American Society for Microbiology.

Covariance Association Test (CVAT) Identifies Genetic Markers Associated with Schizophrenia in Functionally Associated Biological Processes

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Rohde, Palle Duun; Demontis, Ditte; Castro Dias Cuyabano, Beatriz

2016-01-01

was among the top performers. When extending CVAT to utilize a mixture of SNP effects, we found an increase in power to detect the causal sets. Applying the methods to a Danish schizophrenia case–control data set, we found genomic evidence for association of schizophrenia with vitamin A metabolism......Schizophrenia is a psychiatric disorder with large personal and social costs, and understanding the genetic etiology is important. Such knowledge can be obtained by testing the association between a disease phenotype and individual genetic markers; however, such single-marker methods have limited...... genomic best linear unbiased prediction (GBLUP), the covariance association test (CVAT). We compared the performance of CVAT to other commonly used set tests. The comparison was conducted using a simulated study population having the same genetic parameters as for schizophrenia. We found that CVAT...

Genome-wide association study identifies variants in HORMAD2 associated with tonsillectomy

DEFF Research Database (Denmark)

Feenstra, Bjarke; Bager, Peter; Liu, Xueping

2017-01-01

BACKGROUND: Inflammation of the tonsils is a normal response to infection, but some individuals experience recurrent, severe tonsillitis and massive hypertrophy of the tonsils in which case surgical removal of the tonsils may be considered. OBJECTIVE: To identify common genetic variants associate...... the molecular mechanisms underlying the genetic association involve general lymphoid hyper-reaction throughout the mucosa-associated lymphoid tissue system.......BACKGROUND: Inflammation of the tonsils is a normal response to infection, but some individuals experience recurrent, severe tonsillitis and massive hypertrophy of the tonsils in which case surgical removal of the tonsils may be considered. OBJECTIVE: To identify common genetic variants associated...... with tonsillectomy. METHODS: We used tonsillectomy information from Danish health registers and carried out a genome-wide association study comprising 1464 patients and 12 019 controls of Northwestern European ancestry, with replication in an independent sample set of 1575 patients and 1367 controls. RESULTS...

Excess Polθ functions in response to replicative stress in homologous recombination-proficient cancer cells

Directory of Open Access Journals (Sweden)

T. Goullet de Rugy

2016-10-01

Full Text Available DNA polymerase theta (Polθ is a specialized A-family DNA polymerase that functions in processes such as translesion synthesis (TLS, DNA double-strand break repair and DNA replication timing. Overexpression of POLQ, the gene encoding Polθ, is a prognostic marker for an adverse outcome in a wide range of human cancers. While increased Polθ dosage was recently suggested to promote survival of homologous recombination (HR-deficient cancer cells, it remains unclear whether POLQ overexpression could be also beneficial to HR-proficient cancer cells. By performing a short interfering (siRNA screen in which genes encoding druggable proteins were knocked down in Polθ-overexpressing cells as a means to uncover genetic vulnerabilities associated with POLQ overexpression, we could not identify genes that were essential for viability in Polθ-overexpressing cells in normal growth conditions. We also showed that, upon external DNA replication stress, Polθ expression promotes cell survival and limits genetic instability. Finally, we report that POLQ expression correlates with the expression of a set of HR genes in breast, lung and colorectal cancers. Collectively, our data suggest that Polθ upregulation, besides its importance for survival of HR-deficient cancer cells, may be crucial also for HR-proficient cells to better tolerate DNA replication stress, as part of a global gene deregulation response, including HR genes.

Comprehensive genetic study of fatty acids helps explain the role of noncoding inflammatory bowel disease associated SNPs and fatty acid metabolism in disease pathogenesis.

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Jezernik, Gregor; Potočnik, Uroš

2018-03-01

Fatty acids and their derivatives play an important role in inflammation. Diet and genetics influence fatty acid profiles. Abnormalities of fatty acid profiles have been observed in inflammatory bowel diseases (IBD), a group of complex diseases defined by chronic gastrointestinal inflammation. IBD associated fatty acid profile abnormalities were observed independently of nutritional status or disease activity, suggesting a common genetic background. However, no study so far has attempted to look for overlap between IBD loci and fatty acid associated loci or investigate the genetics of fatty acid profiles in IBD. To this end, we conducted a comprehensive genetic study of fatty acid profiles in IBD using iCHIP, a custom microarray platform designed for deep sequencing of immune-mediated disease associated loci. This study identifies 10 loci associated with fatty acid profiles in IBD. The most significant associations were a locus near CBS (p = 7.62 × 10 -8 ) and a locus in LRRK2 (p = 1.4 × 10 -7 ). Of note, this study replicates the FADS gene cluster locus, previously associated with both fatty acid profiles and IBD pathogenesis. Furthermore, we identify 18 carbon chain trans-fatty acids (p = 1.12 × 10 -3 ), total trans-fatty acids (p = 4.49 × 10 -3 ), palmitic acid (p = 5.85 × 10 -3 ) and arachidonic acid (p = 8.58 × 10 -3 ) as significantly associated with IBD pathogenesis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Multiple-cohort genetic association study reveals CXCR6 as a new chemokine receptor involved in long-term nonprogression to AIDS

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Limou, Sophie; Coulonges, Cédric; Herbeck, Joshua T.; van Manen, Daniëlle; An, Ping; Le Clerc, Sigrid; Delaneau, Olivier; Diop, Gora; Taing, Lieng; Montes, Matthieu; van't Wout, Angélique B.; Gottlieb, Geoffrey S.; Therwath, Amu; Rouzioux, Christine; Delfraissy, Jean-François; Lelièvre, Jean-Daniel; Lévy, Yves; Hercberg, Serge; Dina, Christian; Phair, John; Donfield, Sharyne; Goedert, James J.; Buchbinder, Susan; Estaquier, Jérôme; Schächter, François; Gut, Ivo; Froguel, Philippe; Mullins, James I.; Schuitemaker, Hanneke; Winkler, Cheryl; Zagury, Jean-François

2010-01-01

Background. The compilation of previous genomewide association studies of AIDS shows a major polymorphism in the HCP5 gene associated with both control of the viral load and long-term nonprogression (LTNP) to AIDS. Methods. To look for genetic variants that affect LTNP without necessary control of the viral load, we reanalyzed the genomewide data of the unique LTNP Genomics of Resistance to Immunodeficiency Virus (GRIV) cohort by excluding “elite controller” patients, who were controlling the viral load at very low levels (<100 copies/mL). Results. The rs2234358 polymorphism in the CXCR6 gene was the strongest signal (P = 2.5 × 10−7; odds ratio, 1.85) obtained for the genomewide association study comparing the 186 GRIV LTNPs who were not elite controllers with 697 uninfected control subjects. This association was replicated in 3 additional independent European studies, reaching genomewide significance of Pcombined = 9.7 × 10−10. This association with LTNP is independent of the combined CCR2-CCR5 locus and the HCP5 polymorphisms. Conclusion. The statistical significance, the replication, and the magnitude of the association demonstrate that CXCR6 is likely involved in the molecular etiology of AIDS and, in particular, in LTNP, emphasizing the power of extreme-phenotype cohorts. CXCR6 is a chemokine receptor that is known as a minor coreceptor in human immunodeficiency virus type 1 infection but could participate in disease progression through its role as a mediator of inflammation. PMID:20704485

USP7 is a SUMO deubiquitinase essential for DNA replication

DEFF Research Database (Denmark)

Lecona, Emilio; Rodriguez-Acebes, Sara; Specks, Julia

2016-01-01

Post-translational modification of proteins by ubiquitin (Ub) and Ub-like modifiers regulates DNA replication. We have previously shown that chromatin around replisomes is rich in SUMO and poor in Ub, whereas mature chromatin exhibits an opposite pattern. How this SUMO-rich, Ub-poor environment...... is maintained at sites of DNA replication in mammalian cells remains unexplored. Here we identify USP7 as a replisome-enriched SUMO deubiquitinase that is essential for DNA replication. By acting on SUMO and SUMOylated proteins, USP7 counteracts their ubiquitination. Inhibition or genetic deletion of USP7 leads...... to the accumulation of Ub on SUMOylated proteins, which are displaced away from replisomes. Our findings provide a model explaining the differential accumulation of SUMO and Ub at replication forks and identify an essential role of USP7 in DNA replication that should be considered in the development of USP7...

Celiac disease : moving from genetic associations to causal variants

NARCIS (Netherlands)

Hrdlickova, B.; Westra, H-J; Franke, L.; Wijmenga, C.

Genome-wide association studies are providing insight into the genetic basis of common complex diseases: more than 1150 genetic loci [2165 unique single nucleotide polymorphisms (SNPs)] have recently been associated to 159 complex diseases. The hunt for genes contributing to immune-related diseases

Trans-ancestry genome-wide association study identifies 12 genetic loci influencing blood pressure and implicates a role for DNA methylation

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Drong, Alexander W; Abbott, James; Wahl, Simone; Tan, Sian-Tsung; Scott, William R; Campanella, Gianluca; Chadeau-Hyam, Marc; Afzal, Uzma; Ahluwalia, Tarunveer S; Bonder, Marc Jan; Chen, Peng; Dehghan, Abbas; Edwards, Todd L; Esko, Tõnu; Go, Min Jin; Harris, Sarah E; Hartiala, Jaana; Kasela, Silva; Kasturiratne, Anuradhani; Khor, Chiea-Chuen; Kleber, Marcus E; Li, Huaixing; Yu Mok, Zuan; Nakatochi, Masahiro; Sapari, Nur Sabrina; Saxena, Richa; Stewart, Alexandre F R; Stolk, Lisette; Tabara, Yasuharu; Teh, Ai Ling; Wu, Ying; Wu, Jer-Yuarn; Zhang, Yi; Aits, Imke; Da Silva Couto Alves, Alexessander; Das, Shikta; Dorajoo, Rajkumar; Hopewell, Jemma C; Kim, Yun Kyoung; Koivula, Robert W; Luan, Jian’an; Lyytikäinen, Leo-Pekka; Nguyen, Quang N; Pereira, Mark A; Postmus, Iris; Raitakari, Olli T; Bryan, Molly Scannell; Scott, Robert A; Sorice, Rossella; Tragante, Vinicius; Traglia, Michela; White, Jon; Yamamoto, Ken; Zhang, Yonghong; Adair, Linda S; Ahmed, Alauddin; Akiyama, Koichi; Asif, Rasheed; Aung, Tin; Barroso, Inês; Bjonnes, Andrew; Braun, Timothy R; Cai, Hui; Chang, Li-Ching; Chen, Chien-Hsiun; Cheng, Ching-Yu; Chong, Yap-Seng; Collins, Rory; Courtney, Regina; Davies, Gail; Delgado, Graciela; Do, Loi D; Doevendans, Pieter A; Gansevoort, Ron T; Gao, Yu-Tang; Grammer, Tanja B; Grarup, Niels; Grewal, Jagvir; Gu, Dongfeng; Wander, Gurpreet S; Hartikainen, Anna-Liisa; Hazen, Stanley L; He, Jing; Heng, Chew-Kiat; Hixson, James E; Hofman, Albert; Hsu, Chris; Huang, Wei; Husemoen, Lise L N; Hwang, Joo-Yeon; Ichihara, Sahoko; Igase, Michiya; Isono, Masato; Justesen, Johanne M; Katsuya, Tomohiro; Kibriya, Muhammad G; Kim, Young Jin; Kishimoto, Miyako; Koh, Woon-Puay; Kohara, Katsuhiko; Kumari, Meena; Kwek, Kenneth; Lee, Nanette R; Lee, Jeannette; Liao, Jiemin; Lieb, Wolfgang; Liewald, David C M; Matsubara, Tatsuaki; Matsushita, Yumi; Meitinger, Thomas; Mihailov, Evelin; Milani, Lili; Mills, Rebecca; Mononen, Nina; Müller-Nurasyid, Martina; Nabika, Toru; Nakashima, Eitaro; Ng, Hong Kiat; Nikus, Kjell; Nutile, Teresa; Ohkubo, Takayoshi; Ohnaka, Keizo; Parish, Sarah; Paternoster, Lavinia; Peng, Hao; Peters, Annette; Pham, Son T; Pinidiyapathirage, Mohitha J; Rahman, Mahfuzar; Rakugi, Hiromi; Rolandsson, Olov; Ann Rozario, Michelle; Ruggiero, Daniela; Sala, Cinzia F; Sarju, Ralhan; Shimokawa, Kazuro; Snieder, Harold; Sparsø, Thomas; Spiering, Wilko; Starr, John M; Stott, David J; Stram, Daniel O; Sugiyama, Takao; Szymczak, Silke; Tang, W H Wilson; Tong, Lin; Trompet, Stella; Turjanmaa, Väinö; Ueshima, Hirotsugu; Uitterlinden, André G; Umemura, Satoshi; Vaarasmaki, Marja; van Dam, Rob M; van Gilst, Wiek H; van Veldhuisen, Dirk J; Viikari, Jorma S; Waldenberger, Melanie; Wang, Yiqin; Wang, Aili; Wilson, Rory; Wong, Tien-Yin; Xiang, Yong-Bing; Yamaguchi, Shuhei; Ye, Xingwang; Young, Robin D; Young, Terri L; Yuan, Jian-Min; Zhou, Xueya; Asselbergs, Folkert W; Ciullo, Marina; Clarke, Robert; Deloukas, Panos; Franke, Andre; Franks, Paul W; Franks, Steve; Friedlander, Yechiel; Gross, Myron D; Guo, Zhirong; Hansen, Torben; Jarvelin, Marjo-Riitta; Jørgensen, Torben; Jukema, J Wouter; kähönen, Mika; Kajio, Hiroshi; Kivimaki, Mika; Lee, Jong-Young; Lehtimäki, Terho; Linneberg, Allan; Miki, Tetsuro; Pedersen, Oluf; Samani, Nilesh J; Sørensen, Thorkild I A; Takayanagi, Ryoichi; Toniolo, Daniela; Ahsan, Habibul; Allayee, Hooman; Chen, Yuan-Tsong; Danesh, John; Deary, Ian J; Franco, Oscar H; Franke, Lude; Heijman, Bastiaan T; Holbrook, Joanna D; Isaacs, Aaron; Kim, Bong-Jo; Lin, Xu; Liu, Jianjun; März, Winfried; Metspalu, Andres; Mohlke, Karen L; Sanghera, Dharambir K; Shu, Xiao-Ou; van Meurs, Joyce B J; Vithana, Eranga; Wickremasinghe, Ananda R; Wijmenga, Cisca; Wolffenbuttel, Bruce H W; Yokota, Mitsuhiro; Zheng, Wei; Zhu, Dingliang; Vineis, Paolo; Kyrtopoulos, Soterios A; Kleinjans, Jos C S; McCarthy, Mark I; Soong, Richie; Gieger, Christian; Scott, James

2016-01-01

We carried out a trans-ancestry genome-wide association and replication study of blood pressure phenotypes among up to 320,251 individuals of East Asian, European and South Asian ancestry. We find genetic variants at 12 new loci to be associated with blood pressure (P = 3.9 × 10−11 to 5.0 × 10−21). The sentinel blood pressure SNPs are enriched for association with DNA methylation at multiple nearby CpG sites, suggesting that, at some of the loci identified, DNA methylation may lie on the regulatory pathway linking sequence variation to blood pressure. The sentinel SNPs at the 12 new loci point to genes involved in vascular smooth muscle (IGFBP3, KCNK3, PDE3A and PRDM6) and renal (ARHGAP24, OSR1, SLC22A7 and TBX2) function. The new and known genetic variants predict increased left ventricular mass, circulating levels of NT-proBNP, and cardiovascular and all-cause mortality (P = 0.04 to 8.6 × 10−6). Our results provide new evidence for the role of DNA methylation in blood pressure regulation. PMID:26390057

Mcm10 regulates DNA replication elongation by stimulating the CMG replicative helicase.

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Lõoke, Marko; Maloney, Michael F; Bell, Stephen P

2017-02-01

Activation of the Mcm2-7 replicative DNA helicase is the committed step in eukaryotic DNA replication initiation. Although Mcm2-7 activation requires binding of the helicase-activating proteins Cdc45 and GINS (forming the CMG complex), an additional protein, Mcm10, drives initial origin DNA unwinding by an unknown mechanism. We show that Mcm10 binds a conserved motif located between the oligonucleotide/oligosaccharide fold (OB-fold) and A subdomain of Mcm2. Although buried in the interface between these domains in Mcm2-7 structures, mutations predicted to separate the domains and expose this motif restore growth to conditional-lethal MCM10 mutant cells. We found that, in addition to stimulating initial DNA unwinding, Mcm10 stabilizes Cdc45 and GINS association with Mcm2-7 and stimulates replication elongation in vivo and in vitro. Furthermore, we identified a lethal allele of MCM10 that stimulates initial DNA unwinding but is defective in replication elongation and CMG binding. Our findings expand the roles of Mcm10 during DNA replication and suggest a new model for Mcm10 function as an activator of the CMG complex throughout DNA replication. © 2017 Lõoke et al.; Published by Cold Spring Harbor Laboratory Press.

Genetic and epigenetic differences associated with environmental gradients in replicate populations of two salt marsh perennials

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Foust, C.M.; Preite, V.; Schrey, A.W.; Alvarez, M.; Robertson, M.H.; Verhoeven, K.J.F.; Richards, Christina L.

2016-01-01

While traits and trait plasticity are partly genetically based, investigating epigenetic mechanisms may provide more nuanced understanding of the mechanisms underlying response to environment. Using AFLP and methylation-sensitive AFLP, we tested the hypothesis that differentiation to habitats along

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.

Crinivirus replication and host interactions

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Zsofia A Kiss

2013-05-01

Full Text Available Criniviruses comprise one of the genera within the family Closteroviridae. Members in this family are restricted to the phloem and rely on whitefly vectors of the genera Bemisia and/or Trialeurodes for plant-to-plant transmission. All criniviruses have bipartite, positive-sense ssRNA genomes, although there is an unconfirmed report of one having a tripartite genome. Lettuce infectious yellows virus (LIYV is the type species of the genus, the best studied so far of the criniviruses and the first for which a reverse genetics system was available. LIYV RNA 1 encodes for proteins predicted to be involved in replication, and alone is competent for replication in protoplasts. Replication results in accumulation of cytoplasmic vesiculated membranous structures which are characteristic of most studied members of the Closteroviridae. These membranous structures, often referred to as BYV-type vesicles, are likely sites of RNA replication. LIYV RNA 2 is replicated in trans when co-infecting cells with RNA 1, but is temporally delayed relative to RNA1. Efficient RNA 2 replication also is dependent on the RNA 1-encoded RNA binding protein, P34. No LIYV RNA 2-encoded proteins have been shown to affect RNA replication, but at least four, CP, CPm, Hsp70h, and p59 are virion structural components and CPm is a determinant of whitefly transmissibility. Roles of other LIYV RNA 2-encoded proteins are largely as yet unknown, but P26 is a non-virion protein that accumulates in cells as characteristic plasmalemma deposits which in plants are localized within phloem parenchyma and companion cells over plasmodesmata connections to sieve elements. The two remaining crinivirus-conserved RNA 2-encoded proteins are P5 and P9. P5 is 39 amino acid protein and is encoded at the 5’ end of RNA 2 as ORF1 and is part of the hallmark closterovirus gene array. The orthologous gene in BYV has been shown to play a role in cell-to-cell movement and indicated to be localized to the

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...

Chymotrypsinogen C Genetic Variants, Including c.180TT, Are Strongly Associated With Chronic Pancreatitis in Pediatric Patients.

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Grabarczyk, Alicja Monika; Oracz, Grzegorz; Wertheim-Tysarowska, Katarzyna; Kujko, Aleksandra Anna; Wejnarska, Karolina; Kolodziejczyk, Elwira; Bal, Jerzy; Koziel, Dorota; Kowalik, Artur; Gluszek, Stanislaw; Rygiel, Agnieszka Magdalena

2017-12-01

Genetic studies in adults/adolescent patients with chronic pancreatitis (CP) identified chymotrypsinogen C (CTRC) genetic variants but their association with CP risk has been difficult to replicate. To evaluate the risk of CP associated with CTRC variants in CP pediatric patients-control study. The distribution of CTRC variants in CP pediatric cohort (n = 136, median age at CP onset 8 years) with no history of alcohol/smoking abuse was compared with controls (n = 401, median age 45). We showed that p.Arg254Trp (4.6%) and p.Lys247_Arg254del (5.3%) heterozygous mutations are frequent and significantly associated with CP risk in pediatric patients (odds ratio [OR] = 19.1; 95% CI 2.8-160; P = 0.001 and OR = 5.5; 95% CI 1.6-19.4; P = 0.001, respectively). For the first time, we demonstrated that the c.180TT genotype of common p.Gly60Gly variant is strong, an independent CP risk factor (OR = 23; 95% CI 7.7-70; P A variant, both CA and AA genotype, is significantly underrepresented in CP compared with controls (15% vs 35%; OR = 0.33; 95% CI 0.19-0.59; P risk factors. The c.493+51C>A variant may play a protective role against CP development.

Replication and Relevance of Multiple Susceptibility Loci Discovered from Genome Wide Association Studies for Type 2 Diabetes in an Indian Population.

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Nagaraja M Phani

Full Text Available Several genetic variants for type 2 diabetes (T2D have been identified through genome wide association studies (GWAS from Caucasian population; however replication studies were not consistent across various ethnicities. Objective of the current study is to examine the possible correlation of 9 most significant GWAS single nucleotide polymorphisms (SNPs for T2D susceptibility as well as the interactive effect of these variants on the risk of T2D in an Indian population.Case-control cohorts of 1156 individuals were genotyped for 9 SNPs from an Indian population. Association analyses were performed using logistic regression after adjusting for covariates. Multifactor dimensionality reduction (MDR analysis was adopted to determine gene-gene interactions and discriminatory power of combined SNP effect was assessed by grouping individuals based on the number of risk alleles and by calculating area under the receiver-operator characteristic curve (AUC.We confirm the association of TCF7L2 (rs7903146 and SLC30A8 (rs13266634 with T2D. MDR analysis showed statistically significant interactions among four SNPs of SLC30A8 (rs13266634, IGF2BP2 (rs4402960, HHEX (rs1111875 and CDKN2A (rs10811661 genes. Cumulative analysis showed an increase in odds ratio against the baseline group of individuals carrying 5 to 6 risk alleles and discriminatory power of genetic test based on 9 variants showed higher AUC value when analyzed along with body mass index (BMI.These results provide a strong evidence for independent association between T2D and SNPs for in TCF7L2 and SLC30A8. MDR analysis demonstrates that independently non-significant variants may interact with one another resulting in increased disease susceptibility in the population tested.

Genetic loci for retinal arteriolar microcirculation.

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Xueling Sim

Full Text Available Narrow arterioles in the retina have been shown to predict hypertension as well as other vascular diseases, likely through an increase in the peripheral resistance of the microcirculatory flow. In this study, we performed a genome-wide association study in 18,722 unrelated individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium and the Blue Mountain Eye Study, to identify genetic determinants associated with variations in retinal arteriolar caliber. Retinal vascular calibers were measured on digitized retinal photographs using a standardized protocol. One variant (rs2194025 on chromosome 5q14 near the myocyte enhancer factor 2C MEF2C gene was associated with retinal arteriolar caliber in the meta-analysis of the discovery cohorts at genome-wide significance of P-value <5×10(-8. This variant was replicated in an additional 3,939 individuals of European ancestry from the Australian Twins Study and Multi-Ethnic Study of Atherosclerosis (rs2194025, P-value = 2.11×10(-12 in combined meta-analysis of discovery and replication cohorts. In independent studies of modest sample sizes, no significant association was found between this variant and clinical outcomes including coronary artery disease, stroke, myocardial infarction or hypertension. In conclusion, we found one novel loci which underlie genetic variation in microvasculature which may be relevant to vascular disease. The relevance of these findings to clinical outcomes remains to be determined.

Relationship between Trypanosoma brucei rhodesiense genetic diversity and clinical spectrum among sleeping sickness patients in Uganda.

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Kato, Charles D; Mugasa, Claire M; Nanteza, Ann; Matovu, Enock; Alibu, Vincent P

2017-10-27

Human African trypanosomiasis (HAT) due to Trypanosoma brucei rhodesiense in East and southern Africa is reported to be clinically diverse. We tested the hypothesis that this clinical diversity is associated with a variation in trypanosome genotypes. Trypanosome DNA isolated from HAT patients was genotyped using 7 microsatellite markers directly from blood spotted FTA cards following a whole genome amplification. All markers were polymorphic and identified 17 multi-locus genotypes with 56% of the isolates having replicate genotypes. We did not observe any significant clustering between isolates and bootstrap values across major tree nodes were insignificant. When genotypes were compared among patients with varying clinical presentation or outcome, replicate genotypes were observed at both extremes showing no significant association between genetic diversity and clinical outcome. Our study shows that T. b. rhodesiense isolates are homogeneous within a focus and that observed clinical diversity may not be associated with parasite genetic diversity. Other factors like host genetics and environmental factors might be involved in determining clinical diversity. Our study may be important in designing appropriate control measures that target the parasite.

Definition of herpes simplex virus type 1 helper activities for adeno-associated virus early replication events.

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Nathalie Alazard-Dany

2009-03-01

Full Text Available The human parvovirus Adeno-Associated Virus (AAV type 2 can only replicate in cells co-infected with a helper virus, such as Adenovirus or Herpes Simplex Virus type 1 (HSV-1; whereas, in the absence of a helper virus, it establishes a latent infection. Previous studies demonstrated that the ternary HSV-1 helicase/primase (HP complex (UL5/8/52 and the single-stranded DNA-Binding Protein (ICP8 were sufficient to induce AAV-2 replication in transfected cells. We independently showed that, in the context of a latent AAV-2 infection, the HSV-1 ICP0 protein was able to activate rep gene expression. The present study was conducted to integrate these observations and to further explore the requirement of other HSV-1 proteins during early AAV replication steps, i.e. rep gene expression and AAV DNA replication. Using a cellular model that mimics AAV latency and composite constructs coding for various sets of HSV-1 genes, we first confirmed the role of ICP0 for rep gene expression and demonstrated a synergistic effect of ICP4 and, to a lesser extent, ICP22. Conversely, ICP27 displayed an inhibitory effect. Second, our analyses showed that the effect of ICP0, ICP4, and ICP22 on rep gene expression was essential for the onset of AAV DNA replication in conjunction with the HP complex and ICP8. Third, and most importantly, we demonstrated that the HSV-1 DNA polymerase complex (UL30/UL42 was critical to enhance AAV DNA replication to a significant level in transfected cells and that its catalytic activity was involved in this process. Altogether, this work represents the first comprehensive study recapitulating the series of early events taking place during HSV-1-induced AAV replication.

Admixture mapping in the Hispanic Community Health Study/Study of Latinos reveals regions of genetic associations with blood pressure traits.

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Tamar Sofer

Full Text Available Admixture mapping can be used to detect genetic association regions in admixed populations, such as Hispanics/Latinos, by estimating associations between local ancestry allele counts and the trait of interest. We performed admixture mapping of the blood pressure traits systolic and diastolic blood pressure (SBP, DBP, mean arterial pressure (MAP, and pulse pressure (PP, in a dataset of 12,116 participants from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL. Hispanics/Latinos have three predominant ancestral populations (European, African, and Amerindian, for each of which we separately tested local ancestry intervals across the genome. We identified four regions that were significantly associated with a blood pressure trait at the genome-wide admixture mapping level. A 6p21.31 Amerindian ancestry association region has multiple known associations, but none explained the admixture mapping signal. We identified variants that completely explained this signal. One of these variants had p-values of 0.02 (MAP and 0.04 (SBP in replication testing in Pima Indians. A 11q13.4 Amerindian ancestry association region spans a variant that was previously reported (p-value = 0.001 in a targeted association study of Blood Pressure (BP traits and variants in the vitamin D pathway. There was no replication evidence supporting an association in the identified 17q25.3 Amerindian ancestry association region. For a region on 6p12.3, associated with African ancestry, we did not identify any candidate variants driving the association. It may be driven by rare variants. Whole genome sequence data may be necessary to fine map these association signals, which may contribute to disparities in BP traits between diverse populations.

Using case-control designs for genome-wide screening for associations between genetic markers and disease susceptibility loci.

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Yang, Q; Khoury, M J; Atkinson, M; Sun, F; Cheng, R; Flanders, W D

1999-01-01

We used a case-control design to scan the genome for any associations between genetic markers and disease susceptibility loci using the first two replicates of the Mycenaean population from the GAW11 (Problem 2) data. Using a case-control approach, we constructed a series of 2-by-3 tables for each allele of every marker on all six chromosomes. Odds ratios (ORs) and 95% confidence intervals (95% CI) were estimated for all alleles of every marker. We selected the one allele for which the estimated OR had the minimum p-value to plot in the graph. Among these selected ORs, we calculated 95% CI for those that had a p-value Mycenaean population, the case-control design identified allele number 1 of marker 24 on chromosome 1 to be associated with a disease susceptibility gene, OR = 2.10 (95% CI 1.66-2.62). Our approach failed to show any other significant association between case-control status and genetic markers. Stratified analysis on the environmental risk factor (E1) provided no further evidence of significant association other than allele 1 of marker 24 on chromosome 1. These data indicate the absence of linkage disequilibrium for markers flanking loci A, B, and C. Finally, we examined the effect of gene x environment (G x E) interaction for the identified allele. Our results provided no evidence of G x E interaction, but suggested that the environmental exposure alone was a risk factor for the disease.

USP7 is a SUMO deubiquitinase essential for DNA replication

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Lecona, Emilio; Rodriguez-Acebes, Sara; Specks, Julia; Lopez-Contreras, Andres J; Ruppen, Isabel; Murga, Matilde; Muñoz, Javier; Mendez, Juan; Fernandez-Capetillo, Oscar

2016-01-01

Post-translational modification of proteins by ubiquitin (Ub) and Ub-like modifiers regulates various aspects of DNA replication. We previously showed that the chromatin around replisomes is rich in SUMO and depleted in Ub, whereas an opposite pattern is observed in mature chromatin. How this SUMO-rich/Ub-low environment is maintained at sites of DNA replication is not known. Here we identify USP7 as a replisome-enriched SUMO deubiquitinase that is essential for DNA replication. By acting on SUMO and SUMOylated proteins, USP7 counteracts their ubiquitination. Chemical inhibition or genetic deletion of USP7 leads to the accumulation of Ub on SUMOylated proteins, which are displaced to chromatin away from replisomes. Our findings provide a model to explain the differential accumulation of SUMO and Ub at replication forks, and identify an essential role of USP7 in DNA replication that should be taken into account for the use of USP7 inhibitors as anticancer agents. PMID:26950370

Genetic variant in the IGF2BP2 gene may interact with fetal malnutrition to affect glucose metabolism

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van Hoek, Mandy; Langendonk, Janneke G.; de Rooij, Susanne R.; Sijbrands, Eric J. G.; Roseboom, Tessa J.

2009-01-01

OBJECTIVE: Fetal malnutrition may predispose to type 2 diabetes through gene programming and developmental changes. Previous studies showed that these effects may be modulated by genetic variation. Genome-wide association studies discovered and replicated a number of type 2 diabetes-associated

Genetic modifiers of menopausal hormone replacement therapy and breast cancer risk

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Rudolph, Anja; Hein, Rebecca; Lindström, Sara

2013-01-01

Women using menopausal hormone therapy (MHT) are at increased risk of developing breast cancer (BC). To detect genetic modifiers of the association between current use of MHT and BC risk, we conducted a meta-analysis of four genome-wide case-only studies followed by replication in 11 case...

Genetic variants associated with warfarin dose in African-American individuals: a genome-wide association study

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Perera, Minoli A; Cavallari, Larisa H; Limdi, Nita A; Gamazon, Eric R; Konkashbaev, Anuar; Daneshjou, Roxana; Pluzhnikov, Anna; Crawford, Dana C; Wang, Jelai; Liu, Nianjun; Tatonetti, Nicholas; Bourgeois, Stephane; Takahashi, Harumi; Bradford, Yukiko; Burkley, Benjamin M; Desnick, Robert J; Halperin, Jonathan L; Khalifa, Sherief I; Langaee, Taimour Y; Lubitz, Steven A; Nutescu, Edith A; Oetjens, Matthew; Shahin, Mohamed H; Patel, Shitalben R; Sagreiya, Hersh; Tector, Matthew; Weck, Karen E; Rieder, Mark J; Scott, Stuart A; Wu, Alan HB; Burmester, James K; Wadelius, Mia; Deloukas, Panos; Wagner, Michael J; Mushiroda, Taisei; Kubo, Michiaki; Roden, Dan M; Cox, Nancy J; Altman, Russ B; Klein, Teri E; Nakamura, Yusuke; Johnson, Julie A

2013-01-01

Summary Background VKORC1 and CYP2C9 are important contributors to warfarin dose variability, but explain less variability for individuals of African descent than for those of European or Asian descent. We aimed to identify additional variants contributing to warfarin dose requirements in African Americans. Methods We did a genome-wide association study of discovery and replication cohorts. Samples from African-American adults (aged ≥18 years) who were taking a stable maintenance dose of warfarin were obtained at International Warfarin Pharmacogenetics Consortium (IWPC) sites and the University of Alabama at Birmingham (Birmingham, AL, USA). Patients enrolled at IWPC sites but who were not used for discovery made up the independent replication cohort. All participants were genotyped. We did a stepwise conditional analysis, conditioning first for VKORC1 −1639G→A, followed by the composite genotype of CYP2C9*2 and CYP2C9*3. We prespecified a genome-wide significance threshold of p<5×10−8 in the discovery cohort and p<0·0038 in the replication cohort. Findings The discovery cohort contained 533 participants and the replication cohort 432 participants. After the prespecified conditioning in the discovery cohort, we identified an association between a novel single nucleotide polymorphism in the CYP2C cluster on chromosome 10 (rs12777823) and warfarin dose requirement that reached genome-wide significance (p=1·51×10−8). This association was confirmed in the replication cohort (p=5·04×10−5); analysis of the two cohorts together produced a p value of 4·5×10−12. Individuals heterozygous for the rs12777823 A allele need a dose reduction of 6·92 mg/week and those homozygous 9·34 mg/week. Regression analysis showed that the inclusion of rs12777823 significantly improves warfarin dose variability explained by the IWPC dosing algorithm (21% relative improvement). Interpretation A novel CYP2C single nucleotide polymorphism exerts a clinically relevant

Multivariate genetic divergence among sugarcane clones by multivariate analysis associated with mixed models

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Valéria Rosa Lopes

2014-02-01

Full Text Available This work had the aim to evaluate the genetic divergence in sugarcane clones using the methodology of graphic dispersion by principal components analysis associated to linear mixed models, indentifying the more divergent and productive genotypes with more precision, for a subsequent combination. 138 sugarcane clones of the RB97 series of the Sugarcane Breeding Program of the Universidade Federal do Parana, more two standard cultivars were evaluated in three environments, with two replications. The two first components explained 96% of the total variation, sufficiently for explaining the divergence found. The variable that contributed the most to de divergence was kilogram of brix per plot (BKP followed by brix, mass of 10 stalks and number of stalks per plot. The more divergent sugarcane clones were RB975008, RB975112, RB975019, RB975153 and RB975067 and the more productive clones were RB975269, RB977533, RB975102, RB975317 and RB975038.

Evidence for genetic association of RORB with bipolar disorder

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Mick Eric

2009-11-01

Full Text Available Abstract Background Bipolar disorder, particularly in children, is characterized by rapid cycling and switching, making circadian clock genes plausible molecular underpinnings for bipolar disorder. We previously reported work establishing mice lacking the clock gene D-box binding protein (DBP as a stress-reactive genetic animal model of bipolar disorder. Microarray studies revealed that expression of two closely related clock genes, RAR-related orphan receptors alpha (RORA and beta (RORB, was altered in these mice. These retinoid-related receptors are involved in a number of pathways including neurogenesis, stress response, and modulation of circadian rhythms. Here we report association studies between bipolar disorder and single-nucleotide polymorphisms (SNPs in RORA and RORB. Methods We genotyped 355 RORA and RORB SNPs in a pediatric cohort consisting of a family-based sample of 153 trios and an independent, non-overlapping case-control sample of 152 cases and 140 controls. Bipolar disorder in children and adolescents is characterized by increased stress reactivity and frequent episodes of shorter duration; thus our cohort provides a potentially enriched sample for identifying genes involved in cycling and switching. Results We report that four intronic RORB SNPs showed positive associations with the pediatric bipolar phenotype that survived Bonferroni correction for multiple comparisons in the case-control sample. Three RORB haplotype blocks implicating an additional 11 SNPs were also associated with the disease in the case-control sample. However, these significant associations were not replicated in the sample of trios. There was no evidence for association between pediatric bipolar disorder and any RORA SNPs or haplotype blocks after multiple-test correction. In addition, we found no strong evidence for association between the age-at-onset of bipolar disorder with any RORA or RORB SNPs. Conclusion Our findings suggest that clock genes in

A Novel Rrm3 Function in Restricting DNA Replication via an Orc5-Binding Domain Is Genetically Separable from Rrm3 Function as an ATPase/Helicase in Facilitating Fork Progression

DEFF Research Database (Denmark)

Syed, Salahuddin; Madsen, Claus Desler; Rasmussen, Lene J.

2016-01-01

hydroxyurea. This novel Rrm3 function is independent of its established role as an ATPase/helicase in facilitating replication fork progression through polymerase blocking obstacles. Using quantitative mass spectrometry and genetic analyses, we find that the homologous recombination factor Rdh54 and Rad5...

Genetic association analyses implicate aberrant regulation of innate and adaptive immunity genes in the pathogenesis of systemic lupus erythematosus

Science.gov (United States)

Graham, Deborah S Cunninghame; Pinder, Christopher L; Tombleson, Philip; Behrens, Timothy W; Martín, Javier; Fairfax, Benjamin P; Knight, Julian C; Chen, Lingyan; Replogle, Joseph; Syvänen, Ann-Christine; Rönnblom, Lars; Graham, Robert R; Wither, Joan E; Rioux, John D; Alarcón-Riquelme, Marta E; Vyse, Timothy J

2015-01-01

Systemic lupus erythematosus (SLE; OMIM 152700) is a genetically complex autoimmune disease characterized by loss of immune tolerance to nuclear and cell surface antigens. Previous genome-wide association studies (GWAS) had modest sample sizes, reducing their scope and reliability. Our study comprised 7,219 cases and 15,991 controls of European ancestry: a new GWAS, meta-analysis with a published GWAS and a replication study. We have mapped 43 susceptibility loci, including 10 novel associations. Assisted by dense genome coverage, imputation provided evidence for missense variants underpinning associations in eight genes. Other likely causal genes were established by examining associated alleles for cis-acting eQTL effects in a range of ex vivo immune cells. We found an over-representation (n=16) of transcription factors among SLE susceptibility genes. This supports the view that aberrantly regulated gene expression networks in multiple cell types in both the innate and adaptive immune response contribute to the risk of developing SLE. PMID:26502338

Genetics of Beckwith-Wiedemann syndrome-associated tumors: common genetic pathways

NARCIS (Netherlands)

Steenman, M.; Westerveld, A.; Mannens, M.

2000-01-01

A specific subset of solid childhood tumors-Wilms' tumor, adrenocortical carcinoma, rhabdomyosarcoma, and hepatoblastoma-is characterized by its association with Beckwith-Wiedemann syndrome. Genetic abnormalities found in these tumors affect the same chromosome region (11p15), which has been

Diverse replication-associated protein encoding circular DNA viruses in guano samples of Central-Eastern European bats.

Science.gov (United States)

Kemenesi, Gábor; Kurucz, Kornélia; Zana, Brigitta; Földes, Fanni; Urbán, Péter; Vlaschenko, Anton; Kravchenko, Kseniia; Budinski, Ivana; Szodoray-Parádi, Farkas; Bücs, Szilárd; Jére, Csaba; Csősz, István; Szodoray-Parádi, Abigél; Estók, Péter; Görföl, Tamás; Boldogh, Sándor; Jakab, Ferenc

2018-03-01

Circular replication-associated protein encoding single-stranded DNA (CRESS DNA) viruses are increasingly recognized worldwide in a variety of samples. Representative members include well-described veterinary pathogens with worldwide distribution, such as porcine circoviruses or beak and feather disease virus. In addition, numerous novel viruses belonging to the family Circoviridae with unverified pathogenic roles have been discovered in different human samples. Viruses of the family Genomoviridae have also been described as being highly abundant in different faecal and environmental samples, with case reports showing them to be suspected pathogens in human infections. In order to investigate the genetic diversity of these viruses in European bat populations, we tested guano samples from Georgia, Hungary, Romania, Serbia and Ukraine. This resulted in the detection of six novel members of the family Circoviridae and two novel members of the family Genomoviridae. Interestingly, a gemini-like virus, namely niminivirus, which was originally found in raw sewage samples in Nigeria, was also detected in our samples. We analyzed the nucleotide composition of members of the family Circoviridae to determine the possible host origins of these viruses. This study provides the first dataset on CRESS DNA viruses of European bats, and members of several novel viral species were discovered.

The yeast replicative aging model.

Science.gov (United States)

He, Chong; Zhou, Chuankai; Kennedy, Brian K

2018-03-08

It has been nearly three decades since the budding yeast Saccharomyces cerevisiae became a significant model organism for aging research and it has emerged as both simple and powerful. The replicative aging assay, which interrogates the number of times a "mother" cell can divide and produce "daughters", has been a stalwart in these studies, and genetic approaches have led to the identification of hundreds of genes impacting lifespan. More recently, cell biological and biochemical approaches have been developed to determine how cellular processes become altered with age. Together, the tools are in place to develop a holistic view of aging in this single-celled organism. Here, we summarize the current state of understanding of yeast replicative aging with a focus on the recent studies that shed new light on how aging pathways interact to modulate lifespan in yeast. Copyright © 2018. Published by Elsevier B.V.

Stop Stalling: Mus81 Required for Efficient Replication | Center for Cancer Research

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DNA replication is precisely controlled to ensure that daughter cells receive intact, accurate genetic information. Each segment of DNA must be copied only once, and the rate of replication coordinated genome-wide. Mild replication stress slows DNA synthesis and activates a pathway involving the Mus81 endonuclease, which generates a series of DNA breaks that are rapidly repaired, allowing the cell to avoid activating the S-phase checkpoint and its potentially damaging outcomes of apoptosis or error-prone repair. Mirit Aladjem, Ph.D., of CCR’s Developmental Therapeutics Branch, and her colleagues wondered whether Mus81 also plays a role in regulating the replication rate during growth in the absence of stress.

Anti-TNF treatment response in rheumatoid arthritis patients is associated with genetic variation in the NLRP3-inflammasome

DEFF Research Database (Denmark)

Sode, Jacob; Vogel, Ulla; Bank, Steffen

2014-01-01

OBJECTIVE: Many patients with rheumatoid arthritis (RA) benefit from tumor necrosis factor-α blocking treatment (anti-TNF), but about one third do not respond. The objective of this study was to replicate and extend previously found associations between anti-TNF treatment response and genetic...... logistic regression analyses were performed to test associations between genotypes and treatment response at 3-6 months using the European League Against Rheumatism (EULAR) response criterion. American College of Rheumatology treatment response (ACR50) and relative change in 28-joint disease activity score.......36-0.98), p = 0.040, q = 0.76). Current smokers who carried the NLRP3(rs4612666) variant allele were less likely to benefit from anti-TNF treatment (OR = 0.24 (0.10-0.56), p = 0.001, q = 0.04). CONCLUSIONS: In a population of Danish RA patients, we confirm the NLRP3 gene as associated with EULAR anti...

Assessing the quality of studies supporting genetic susceptibility and outcomes of ARDS

Directory of Open Access Journals (Sweden)

Marialbert eAcosta-Herrera

2014-02-01

Full Text Available The acute respiratory distress syndrome (ARDS is a severe inflammatory disease manifested as a result of pulmonary and systemic responses to several insults. It is now well accepted that genetic variation influences these responses. However, little is known about the genes that are responsible for patient susceptibility and outcome of ARDS. Methodological flaws are still abundant among genetic association studies with ARDS and here, we aimed to highlight the quality criteria where the standards have not been reached, to expose the associated genes to facilitate replication attempts, and to provide quick-reference guidance for future studies. We conducted a PubMed search from January 2008 to September 2012 for original articles. Studies were considered if a statistically significant association was declared with either susceptibility or outcomes of all-cause ARDS. Fourteen criteria were used for evaluation and results were compared to those from a previous quality assessment report. Significant improvements affecting study design and statistical analysis were detected. However, major issues such as adjustments for the underlying population stratification and replication studies remain poorly addressed.

Moving into a new era of periodontal genetic studies: relevance of large case-control samples using severe phenotypes for genome-wide association studies

NARCIS (Netherlands)

Vaithilingam, R.D.; Saffi, S.H.; Baharuddin, N.A.; Ng, C.C.; Cheong, S.C.; Bartold, P.M.; Schaefer, A.S.; Loos, B.G.

2014-01-01

Studies to elucidate the role of genetics as a risk factor for periodontal disease have gone through various phases. In the majority of cases, the initial ‘hypothesis-dependent’ candidate-gene polymorphism studies did not report valid genetic risk loci. Following a large-scale replication study,

Genetic and Non-genetic Factors Associated With Constipation in Cancer Patients Receiving Opioids.

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Laugsand, Eivor A; Skorpen, Frank; Kaasa, Stein; Sabatowski, Rainer; Strasser, Florian; Fayers, Peter; Klepstad, Pål

2015-06-18

To examine whether the inter-individual variation in constipation among patients receiving opioids for cancer pain is associated with genetic or non-genetic factors. Cancer patients receiving opioids were included from 17 centers in 11 European countries. Intensity of constipation was reported by 1,568 patients on a four-point categorical scale. Non-genetic factors were included as covariates in stratified regression analyses on the association between constipation and 75 single-nucleotide polymorphisms (SNPs) within 15 candidate genes related to opioid- or constipation-signaling pathways (HTR3E, HTR4, HTR2A, TPH1, ADRA2A, CHRM3, TACR1, CCKAR, KIT, ARRB2, GHRL, ABCB1, COMT, OPRM1, and OPRD1). The non-genetic factors significantly associated with constipation were type of laxative, mobility and place of care among patients receiving laxatives (N=806), in addition to Karnofsky performance status and presence of metastases among patients not receiving laxatives (N=762) (Pconstipation. Five SNPs, rs1800532 in TPH1, rs1799971 in OPRM1, rs4437575 in ABCB1, rs10802789 in CHRM3, and rs2020917 in COMT were associated with constipation (Phospitalization, Karnofsky performance status, presence of metastases, and five SNPs within TPH1, OPRM1, ABCB1, CHRM3, and COMT may contribute to the variability in constipation among cancer patients treated with opioids. Knowledge of these factors may help to develop new therapies and to identify patients needing a more individualized approach to treatment.

Genome-wide association study of antisocial personality disorder.

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Rautiainen, M-R; Paunio, T; Repo-Tiihonen, E; Virkkunen, M; Ollila, H M; Sulkava, S; Jolanki, O; Palotie, A; Tiihonen, J

2016-09-06

The pathophysiology of antisocial personality disorder (ASPD) remains unclear. Although the most consistent biological finding is reduced grey matter volume in the frontal cortex, about 50% of the total liability to developing ASPD has been attributed to genetic factors. The contributing genes remain largely unknown. Therefore, we sought to study the genetic background of ASPD. We conducted a genome-wide association study (GWAS) and a replication analysis of Finnish criminal offenders fulfilling DSM-IV criteria for ASPD (N=370, N=5850 for controls, GWAS; N=173, N=3766 for controls and replication sample). The GWAS resulted in suggestive associations of two clusters of single-nucleotide polymorphisms at 6p21.2 and at 6p21.32 at the human leukocyte antigen (HLA) region. Imputation of HLA alleles revealed an independent association with DRB1*01:01 (odds ratio (OR)=2.19 (1.53-3.14), P=1.9 × 10(-5)). Two polymorphisms at 6p21.2 LINC00951-LRFN2 gene region were replicated in a separate data set, and rs4714329 reached genome-wide significance (OR=1.59 (1.37-1.85), P=1.6 × 10(-9)) in the meta-analysis. The risk allele also associated with antisocial features in the general population conditioned for severe problems in childhood family (β=0.68, P=0.012). Functional analysis in brain tissue in open access GTEx and Braineac databases revealed eQTL associations of rs4714329 with LINC00951 and LRFN2 in cerebellum. In humans, LINC00951 and LRFN2 are both expressed in the brain, especially in the frontal cortex, which is intriguing considering the role of the frontal cortex in behavior and the neuroanatomical findings of reduced gray matter volume in ASPD. To our knowledge, this is the first study showing genome-wide significant and replicable findings on genetic variants associated with any personality disorder.

Genome-wide association study of antisocial personality disorder

Science.gov (United States)

Rautiainen, M-R; Paunio, T; Repo-Tiihonen, E; Virkkunen, M; Ollila, H M; Sulkava, S; Jolanki, O; Palotie, A; Tiihonen, J

2016-01-01

The pathophysiology of antisocial personality disorder (ASPD) remains unclear. Although the most consistent biological finding is reduced grey matter volume in the frontal cortex, about 50% of the total liability to developing ASPD has been attributed to genetic factors. The contributing genes remain largely unknown. Therefore, we sought to study the genetic background of ASPD. We conducted a genome-wide association study (GWAS) and a replication analysis of Finnish criminal offenders fulfilling DSM-IV criteria for ASPD (N=370, N=5850 for controls, GWAS; N=173, N=3766 for controls and replication sample). The GWAS resulted in suggestive associations of two clusters of single-nucleotide polymorphisms at 6p21.2 and at 6p21.32 at the human leukocyte antigen (HLA) region. Imputation of HLA alleles revealed an independent association with DRB1*01:01 (odds ratio (OR)=2.19 (1.53–3.14), P=1.9 × 10-5). Two polymorphisms at 6p21.2 LINC00951–LRFN2 gene region were replicated in a separate data set, and rs4714329 reached genome-wide significance (OR=1.59 (1.37–1.85), P=1.6 × 10−9) in the meta-analysis. The risk allele also associated with antisocial features in the general population conditioned for severe problems in childhood family (β=0.68, P=0.012). Functional analysis in brain tissue in open access GTEx and Braineac databases revealed eQTL associations of rs4714329 with LINC00951 and LRFN2 in cerebellum. In humans, LINC00951 and LRFN2 are both expressed in the brain, especially in the frontal cortex, which is intriguing considering the role of the frontal cortex in behavior and the neuroanatomical findings of reduced gray matter volume in ASPD. To our knowledge, this is the first study showing genome-wide significant and replicable findings on genetic variants associated with any personality disorder. PMID:27598967

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics; Volume 80; Issue 1. Testing quantum dynamics in genetic information processing ... Keywords. assembly; computation; database search; DNA replication; genetic information; nucleotide base; polymerase enzyme; quantum coherence; quantum mechanics; quantum superposition.

Methods for Analyzing Multivariate Phenotypes in Genetic Association Studies

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Qiong Yang

2012-01-01

Full Text Available Multivariate phenotypes are frequently encountered in genetic association studies. The purpose of analyzing multivariate phenotypes usually includes discovery of novel genetic variants of pleiotropy effects, that is, affecting multiple phenotypes, and the ultimate goal of uncovering the underlying genetic mechanism. In recent years, there have been new method development and application of existing statistical methods to such phenotypes. In this paper, we provide a review of the available methods for analyzing association between a single marker and a multivariate phenotype consisting of the same type of components (e.g., all continuous or all categorical or different types of components (e.g., some are continuous and others are categorical. We also reviewed causal inference methods designed to test whether the detected association with the multivariate phenotype is truly pleiotropy or the genetic marker exerts its effects on some phenotypes through affecting the others.

The -351A>G genetic polymorphism in the estrogen receptor alpha gene and risk of endometriosis: a case-control study

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Reihaneh Asadi

2015-03-01

Conclusion: The results do not support the previous findings of an association between -351A>G genetic polymorphism in ESR1 gene and endometriosis. Therefore, comprehensive genetic approaches including linkage analyses and family-based tests, together with a number of replication studies with large sample size, are needed to make conclusive claims about the role of this genetic polymorphism in susceptibility to endometriosis.

Genome-wide association study identifies 74 loci associated with educational attainment

DEFF Research Database (Denmark)

Okbay, Aysu; P. Beauchamp, Jonathan; Alan Fontana, Mark

2016-01-01

-nucleotide polymorphisms associated with educational attainment are disproportionately found in genomic regions regulating gene expression in the fetal brain. Candidate genes are preferentially expressed in neural tissue, especially during the prenatal period, and enriched for biological pathways involved in neural......Educational attainment is strongly influenced by social and other environmental factors, but genetic factors are estimated to account for at least 20% of the variation across individuals1. Here we report the results of a genome-wide association study (GWAS) for educational attainment that extends...... development. Our findings demonstrate that, even for a behavioural phenotype that is mostly environmentally determined, a well-powered GWAS identifies replicable associated genetic variants that suggest biologically relevant pathways. Because educational attainment is measured in large numbers of individuals...

Chronic DNA Replication Stress Reduces Replicative Lifespan of Cells by TRP53-Dependent, microRNA-Assisted MCM2-7 Downregulation.

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Gongshi Bai

2016-01-01

Full Text Available Circumstances that compromise efficient DNA replication, such as disruptions to replication fork progression, cause a state known as DNA replication stress (RS. Whereas normally proliferating cells experience low levels of RS, excessive RS from intrinsic or extrinsic sources can trigger cell cycle arrest and senescence. Here, we report that a key driver of RS-induced senescence is active downregulation of the Minichromosome Maintenance 2-7 (MCM2-7 factors that are essential for replication origin licensing and which constitute the replicative helicase core. Proliferating cells produce high levels of MCM2-7 that enable formation of dormant origins that can be activated in response to acute, experimentally-induced RS. However, little is known about how physiological RS levels impact MCM2-7 regulation. We found that chronic exposure of primary mouse embryonic fibroblasts (MEFs to either genetically-encoded or environmentally-induced RS triggered gradual MCM2-7 repression, followed by inhibition of replication and senescence that could be accelerated by MCM hemizygosity. The MCM2-7 reduction in response to RS is TRP53-dependent, and involves a group of Trp53-dependent miRNAs, including the miR-34 family, that repress MCM expression in replication-stressed cells before they undergo terminal cell cycle arrest. miR-34 ablation partially rescued MCM2-7 downregulation and genomic instability in mice with endogenous RS. Together, these data demonstrate that active MCM2-7 repression is a physiologically important mechanism for RS-induced cell cycle arrest and genome maintenance on an organismal level.

The roles of membranes and associated cytoskeleton in plant virus replication and cell-to-cell movement.

Science.gov (United States)

Pitzalis, Nicolas; Heinlein, Manfred

2017-12-18

The infection of plants by viruses depends on cellular mechanisms that support the replication of the viral genomes, and the cell-to-cell and systemic movement of the virus via plasmodesmata (PD) and the connected phloem. While the propagation of some viruses requires the conventional endoplasmic reticulum (ER)-Golgi pathway, others replicate and spread between cells in association with the ER and are independent of this pathway. Using selected viruses as examples, this review re-examines the involvement of membranes and the cytoskeleton during virus infection and proposes potential roles of class VIII myosins and membrane-tethering proteins in controlling viral functions at specific ER subdomains, such as cortical microtubule-associated ER sites, ER-plasma membrane contact sites, and PD. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

The genetic architecture of the human immune system: a bioresource for autoimmunity and disease pathogenesis.

Science.gov (United States)

Roederer, Mario; Quaye, Lydia; Mangino, Massimo; Beddall, Margaret H; Mahnke, Yolanda; Chattopadhyay, Pratip; Tosi, Isabella; Napolitano, Luca; Terranova Barberio, Manuela; Menni, Cristina; Villanova, Federica; Di Meglio, Paola; Spector, Tim D; Nestle, Frank O

2015-04-09

Despite recent discoveries of genetic variants associated with autoimmunity and infection, genetic control of the human immune system during homeostasis is poorly understood. We undertook a comprehensive immunophenotyping approach, analyzing 78,000 immune traits in 669 female twins. From the top 151 heritable traits (up to 96% heritable), we used replicated GWAS to obtain 297 SNP associations at 11 genetic loci, explaining up to 36% of the variation of 19 traits. We found multiple associations with canonical traits of all major immune cell subsets and uncovered insights into genetic control for regulatory T cells. This data set also revealed traits associated with loci known to confer autoimmune susceptibility, providing mechanistic hypotheses linking immune traits with the etiology of disease. Our data establish a bioresource that links genetic control elements associated with normal immune traits to common autoimmune and infectious diseases, providing a shortcut to identifying potential mechanisms of immune-related diseases. Copyright © 2015 Elsevier Inc. All rights reserved.

Estimating Effect Sizes and Expected Replication Probabilities from GWAS Summary Statistics

DEFF Research Database (Denmark)

Holland, Dominic; Wang, Yunpeng; Thompson, Wesley K

2016-01-01

Genome-wide Association Studies (GWAS) result in millions of summary statistics ("z-scores") for single nucleotide polymorphism (SNP) associations with phenotypes. These rich datasets afford deep insights into the nature and extent of genetic contributions to complex phenotypes such as psychiatric......-scores, as such knowledge would enhance causal SNP and gene discovery, help elucidate mechanistic pathways, and inform future study design. Here we present a parsimonious methodology for modeling effect sizes and replication probabilities, relying only on summary statistics from GWAS substudies, and a scheme allowing...... for estimating the degree of polygenicity of the phenotype and predicting the proportion of chip heritability explainable by genome-wide significant SNPs in future studies with larger sample sizes. We apply the model to recent GWAS of schizophrenia (N = 82,315) and putamen volume (N = 12,596), with approximately...

Potential genetic modifiers of disease risk and age at onset in patients with frontotemporal lobar degeneration and GRN mutations: a genome-wide association study.

Science.gov (United States)

Pottier, Cyril; Zhou, Xiaolai; Perkerson, Ralph B; Baker, Matt; Jenkins, Gregory D; Serie, Daniel J; Ghidoni, Roberta; Benussi, Luisa; Binetti, Giuliano; López de Munain, Adolfo; Zulaica, Miren; Moreno, Fermin; Le Ber, Isabelle; Pasquier, Florence; Hannequin, Didier; Sánchez-Valle, Raquel; Antonell, Anna; Lladó, Albert; Parsons, Tammee M; Finch, NiCole A; Finger, Elizabeth C; Lippa, Carol F; Huey, Edward D; Neumann, Manuela; Heutink, Peter; Synofzik, Matthis; Wilke, Carlo; Rissman, Robert A; Slawek, Jaroslaw; Sitek, Emilia; Johannsen, Peter; Nielsen, Jørgen E; Ren, Yingxue; van Blitterswijk, Marka; DeJesus-Hernandez, Mariely; Christopher, Elizabeth; Murray, Melissa E; Bieniek, Kevin F; Evers, Bret M; Ferrari, Camilla; Rollinson, Sara; Richardson, Anna; Scarpini, Elio; Fumagalli, Giorgio G; Padovani, Alessandro; Hardy, John; Momeni, Parastoo; Ferrari, Raffaele; Frangipane, Francesca; Maletta, Raffaele; Anfossi, Maria; Gallo, Maura; Petrucelli, Leonard; Suh, EunRan; Lopez, Oscar L; Wong, Tsz H; van Rooij, Jeroen G J; Seelaar, Harro; Mead, Simon; Caselli, Richard J; Reiman, Eric M; Noel Sabbagh, Marwan; Kjolby, Mads; Nykjaer, Anders; Karydas, Anna M; Boxer, Adam L; Grinberg, Lea T; Grafman, Jordan; Spina, Salvatore; Oblak, Adrian; Mesulam, M-Marsel; Weintraub, Sandra; Geula, Changiz; Hodges, John R; Piguet, Olivier; Brooks, William S; Irwin, David J; Trojanowski, John Q; Lee, Edward B; Josephs, Keith A; Parisi, Joseph E; Ertekin-Taner, Nilüfer; Knopman, David S; Nacmias, Benedetta; Piaceri, Irene; Bagnoli, Silvia; Sorbi, Sandro; Gearing, Marla; Glass, Jonathan; Beach, Thomas G; Black, Sandra E; Masellis, Mario; Rogaeva, Ekaterina; Vonsattel, Jean-Paul; Honig, Lawrence S; Kofler, Julia; Bruni, Amalia C; Snowden, Julie; Mann, David; Pickering-Brown, Stuart; Diehl-Schmid, Janine; Winkelmann, Juliane; Galimberti, Daniela; Graff, Caroline; Öijerstedt, Linn; Troakes, Claire; Al-Sarraj, Safa; Cruchaga, Carlos; Cairns, Nigel J; Rohrer, Jonathan D; Halliday, Glenda M; Kwok, John B; van Swieten, John C; White, Charles L; Ghetti, Bernardino; Murell, Jill R; Mackenzie, Ian R A; Hsiung, Ging-Yuek R; Borroni, Barbara; Rossi, Giacomina; Tagliavini, Fabrizio; Wszolek, Zbigniew K; Petersen, Ronald C; Bigio, Eileen H; Grossman, Murray; Van Deerlin, Vivianna M; Seeley, William W; Miller, Bruce L; Graff-Radford, Neill R; Boeve, Bradley F; Dickson, Dennis W; Biernacka, Joanna M; Rademakers, Rosa

2018-06-01

Loss-of-function mutations in GRN cause frontotemporal lobar degeneration (FTLD). Patients with GRN mutations present with a uniform subtype of TAR DNA-binding protein 43 (TDP-43) pathology at autopsy (FTLD-TDP type A); however, age at onset and clinical presentation are variable, even within families. We aimed to identify potential genetic modifiers of disease onset and disease risk in GRN mutation carriers. The study was done in three stages: a discovery stage, a replication stage, and a meta-analysis of the discovery and replication data. In the discovery stage, genome-wide logistic and linear regression analyses were done to test the association of genetic variants with disease risk (case or control status) and age at onset in patients with a GRN mutation and controls free of neurodegenerative disorders. Suggestive loci (p<1 × 10 -5 ) were genotyped in a replication cohort of patients and controls, followed by a meta-analysis. The effect of genome-wide significant variants at the GFRA2 locus on expression of GFRA2 was assessed using mRNA expression studies in cerebellar tissue samples from the Mayo Clinic brain bank. The effect of the GFRA2 locus on progranulin concentrations was studied using previously generated ELISA-based expression data. Co-immunoprecipitation experiments in HEK293T cells were done to test for a direct interaction between GFRA2 and progranulin. Individuals were enrolled in the current study between Sept 16, 2014, and Oct 5, 2017. After quality control measures, statistical analyses in the discovery stage included 382 unrelated symptomatic GRN mutation carriers and 1146 controls free of neurodegenerative disorders collected from 34 research centres located in the USA, Canada, Australia, and Europe. In the replication stage, 210 patients (67 symptomatic GRN mutation carriers and 143 patients with FTLD without GRN mutations pathologically confirmed as FTLD-TDP type A) and 1798 controls free of neurodegenerative diseases were recruited

Population genetic diversity and fitness in multiple environments

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McGreevy Thomas J

2010-07-01

Full Text Available Abstract Background When a large number of alleles are lost from a population, increases in individual homozygosity may reduce individual fitness through inbreeding depression. Modest losses of allelic diversity may also negatively impact long-term population viability by reducing the capacity of populations to adapt to altered environments. However, it is not clear how much genetic diversity within populations may be lost before populations are put at significant risk. Development of tools to evaluate this relationship would be a valuable contribution to conservation biology. To address these issues, we have created an experimental system that uses laboratory populations of an estuarine crustacean, Americamysis bahia with experimentally manipulated levels of genetic diversity. We created replicate cultures with five distinct levels of genetic diversity and monitored them for 16 weeks in both permissive (ambient seawater and stressful conditions (diluted seawater. The relationship between molecular genetic diversity at presumptive neutral loci and population vulnerability was assessed by AFLP analysis. Results Populations with very low genetic diversity demonstrated reduced fitness relative to high diversity populations even under permissive conditions. Population performance decreased in the stressful environment for all levels of genetic diversity relative to performance in the permissive environment. Twenty percent of the lowest diversity populations went extinct before the end of the study in permissive conditions, whereas 73% of the low diversity lines went extinct in the stressful environment. All high genetic diversity populations persisted for the duration of the study, although population sizes and reproduction were reduced under stressful environmental conditions. Levels of fitness varied more among replicate low diversity populations than among replicate populations with high genetic diversity. There was a significant correlation

Non-replication of the association between 5HTTLPR and response to psychological therapy for child anxiety disorders

Science.gov (United States)

Lester, Kathryn J.; Roberts, Susanna; Keers, Robert; Coleman, Jonathan R. I.; Breen, Gerome; Wong, Chloe C. Y.; Xu, Xiaohui; Arendt, Kristian; Blatter-Meunier, Judith; Bögels, Susan; Cooper, Peter; Creswell, Cathy; Heiervang, Einar R.; Herren, Chantal; Hogendoorn, Sanne M.; Hudson, Jennifer L.; Krause, Karen; Lyneham, Heidi J.; McKinnon, Anna; Morris, Talia; Nauta, Maaike H.; Rapee, Ronald M.; Rey, Yasmin; Schneider, Silvia; Schneider, Sophie C.; Silverman, Wendy K.; Smith, Patrick; Thastum, Mikael; Thirlwall, Kerstin; Waite, Polly; Wergeland, Gro Janne; Eley, Thalia C.

2016-01-01

Background We previously reported an association between 5HTTLPR genotype and outcome following cognitive–behavioural therapy (CBT) in child anxiety (Cohort 1). Children homozygous for the low-expression short-allele showed more positive outcomes. Other similar studies have produced mixed results, with most reporting no association between genotype and CBT outcome. Aims To replicate the association between 5HTTLPR and CBT outcome in child anxiety from the Genes for Treatment study (GxT Cohort 2, n = 829). Method Logistic and linear mixed effects models were used to examine the relationship between 5HTTLPR and CBT outcomes. Mega-analyses using both cohorts were performed. Results There was no significant effect of 5HTTLPR on CBT outcomes in Cohort 2. Mega-analyses identified a significant association between 5HTTLPR and remission from all anxiety disorders at follow-up (odds ratio 0.45, P = 0.014), but not primary anxiety disorder outcomes. Conclusions The association between 5HTTLPR genotype and CBT outcome did not replicate. Short-allele homozygotes showed more positive treatment outcomes, but with small, non-significant effects. Future studies would benefit from utilising whole genome approaches and large, homogenous samples. PMID:26294368

Validation of reported genetic risk factors for periodontitis in a large-scale replication study

NARCIS (Netherlands)

Schaefer, A.S.; Bochenek, G.; Manke, T.; Nothnagel, M.; Graetz, C.; Thien, A.; Jockel-Schneider, Y.; Harks, I.; Staufenbiel, I.; Wijmenga, C.; Eberhard, J.; Guzeldemir-Akcakanat, E.; Cine, N.; Folwaczny, M.; Noack, B.; Meyle, J.; Eickholz, P.; Trombelli, L.; Scapoli, C.; Nohutcu, R.; Bruckmann, C.; Doerfer, C.; Jepsen, S.; Loos, B.G.; Schreiber, S.

2013-01-01

Aim Many studies investigated the role of genetic variants in periodontitis, but few were established as risk factors. We aimed to validate the associations of recent candidate genes in aggressive periodontitis (AgP). Material and Methods We analysed 23 genes in 600 German AgP patients and 1441

Validation of reported genetic risk factors for periodontitis in a large-scale replication study

NARCIS (Netherlands)

Schaefer, Arne S.; Bochenek, Gregor; Manke, Thomas; Nothnagel, Michael; Graetz, Christian; Thien, Anneke; Jockel-Schneider, Yvonne; Harks, Inga; Staufenbiel, Ingmar; Wijmenga, Cisca; Eberhard, Joerg; Guzeldemir-Akcakanat, Esra; Cine, Naci; Folwaczny, Mathias; Noack, Barbara; Meyle, Joerg; Eickholz, Peter; Trombelli, Leonardo; Scapoli, Chiara; Nohutcu, Rahime; Bruckmann, Corinna; Doerfer, Christof; Jepsen, Soren; Loos, Bruno G.; Schreiber, Stefan

Aim Many studies investigated the role of genetic variants in periodontitis, but few were established as risk factors. We aimed to validate the associations of recent candidate genes in aggressive periodontitis (AgP). Material and Methods We analysed 23 genes in 600 German AgP patients and 1441

DNA Replication Is Required for Circadian Clock Function by Regulating Rhythmic Nucleosome Composition.

Science.gov (United States)

Liu, Xiao; Dang, Yunkun; Matsu-Ura, Toru; He, Yubo; He, Qun; Hong, Christian I; Liu, Yi

2017-07-20

Although the coupling between circadian and cell cycles allows circadian clocks to gate cell division and DNA replication in many organisms, circadian clocks were thought to function independently of cell cycle. Here, we show that DNA replication is required for circadian clock function in Neurospora. Genetic and pharmacological inhibition of DNA replication abolished both overt and molecular rhythmicities by repressing frequency (frq) gene transcription. DNA replication is essential for the rhythmic changes of nucleosome composition at the frq promoter. The FACT complex, known to be involved in histone disassembly/reassembly, is required for clock function and is recruited to the frq promoter in a replication-dependent manner to promote replacement of histone H2A.Z by H2A. Finally, deletion of H2A.Z uncoupled the dependence of the circadian clock on DNA replication. Together, these results establish circadian clock and cell cycle as interdependent coupled oscillators and identify DNA replication as a critical process in the circadian mechanism. Published by Elsevier Inc.

Genetic diversity, population structure and marker trait associations ...

Indian Academy of Sciences (India)

Supplementary data: Genetic diversity, population structure and marker trait associations for seed quality traits in cotton (Gossypium hirsutum). Ashok Badigannavar and Gerald O. Myers. J. Genet. 94, 87–94. Table 1. List of cotton germplasm lines used in this study. Germplasm no. Cultivar. Region. Germplasm no. Cultivar.

Genetic Variations and their Association with Diseases among ...

African Journals Online (AJOL)

genetics plays in disease, death and infections. The mode of study involved a combination of a retrospective study and the analysis of genetic variation among Kenyan ethnic populations using ABO blood group system. The results showed that there was association between allele frequencies of ABO system and disease ...

Molecular genetics of nicotine dependence and abstinence: whole genome association using 520,000 SNPs

Directory of Open Access Journals (Sweden)

Walther Donna

2007-04-01

Full Text Available Abstract Background Classical genetic studies indicate that nicotine dependence is a substantially heritable complex disorder. Genetic vulnerabilities to nicotine dependence largely overlap with genetic vulnerabilities to dependence on other addictive substances. Successful abstinence from nicotine displays substantial heritable components as well. Some of the heritability for the ability to quit smoking appears to overlap with the genetics of nicotine dependence and some does not. We now report genome wide association studies of nicotine dependent individuals who were successful in abstaining from cigarette smoking, nicotine dependent individuals who were not successful in abstaining and ethnically-matched control subjects free from substantial lifetime use of any addictive substance. Results These data, and their comparison with data that we have previously obtained from comparisons of four other substance dependent vs control samples support two main ideas: 1 Single nucleotide polymorphisms (SNPs whose allele frequencies distinguish nicotine-dependent from control individuals identify a set of genes that overlaps significantly with the set of genes that contain markers whose allelic frequencies distinguish the four other substance dependent vs control groups (p vs unsuccessful abstainers cluster in small genomic regions in ways that are highly unlikely to be due to chance (Monte Carlo p Conclusion These clustered SNPs nominate candidate genes for successful abstinence from smoking that are implicated in interesting functions: cell adhesion, enzymes, transcriptional regulators, neurotransmitters and receptors and regulation of DNA, RNA and proteins. As these observations are replicated, they will provide an increasingly-strong basis for understanding mechanisms of successful abstinence, for identifying individuals more or less likely to succeed in smoking cessation efforts and for tailoring therapies so that genotypes can help match smokers

Multivariate Methods for Meta-Analysis of Genetic Association Studies.

Science.gov (United States)

Dimou, Niki L; Pantavou, Katerina G; Braliou, Georgia G; Bagos, Pantelis G

2018-01-01

Multivariate meta-analysis of genetic association studies and genome-wide association studies has received a remarkable attention as it improves the precision of the analysis. Here, we review, summarize and present in a unified framework methods for multivariate meta-analysis of genetic association studies and genome-wide association studies. Starting with the statistical methods used for robust analysis and genetic model selection, we present in brief univariate methods for meta-analysis and we then scrutinize multivariate methodologies. Multivariate models of meta-analysis for a single gene-disease association studies, including models for haplotype association studies, multiple linked polymorphisms and multiple outcomes are discussed. The popular Mendelian randomization approach and special cases of meta-analysis addressing issues such as the assumption of the mode of inheritance, deviation from Hardy-Weinberg Equilibrium and gene-environment interactions are also presented. All available methods are enriched with practical applications and methodologies that could be developed in the future are discussed. Links for all available software implementing multivariate meta-analysis methods are also provided.

Genetics of COPD

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Hidetoshi Nakamura

2011-01-01

Full Text Available Previous family studies suggested that genetic variation contributes to COPD susceptibility. The only gene proven to influence COPD susceptibility is SERPINA1, encoding α1-antitrypsin. Most studies on COPD candidate genes except SERPINA1, have not been consistently replicated. However, longitudinal studies of decline in lung function, meta-analyses of candidate gene studies, and family-based linkage analyses suggested that variants in EPHX1, GST, MMP12, TGFB1, and SERPINE2 were associated with susceptibility to COPD. A genome-wide association (GWA study has recently demonstrated that CHRNA3/5 in 15q25 was associated with COPD compared with control smokers. It was of interest that the CHRNA3/5 locus was associated with nicotine dependence and lung cancer as well. The associations of HHIP on 4q31 and FAM13A on 4q22 with COPD were also suggested in GWA studies. Another GWA study has shown that BICD1 in 12p11 was associated with the presence or absence of emphysema. Although every genetic study on COPD has some limitations including heterogeneity in smoking behaviors and comorbidities, it has contributed to the progress in elucidating the pathogenesis of COPD. Future studies will make us understand the mechanisms underlying the polygenic disease, leading to the development of a specific treatment for each phenotype.

Expression of heterologous genes from an IRES translational cassette in replication-competent murine leukemia virus vectors

DEFF Research Database (Denmark)

Jespersen, T.; Duch, M.; Carrasco, M.L.

1999-01-01

of spliced env mRNA for the SL3-3 derived vector relative to the Akv derived vectors, seemingly contributing to its low replication capacity. The EGFP expressing Akv-MLV was genetically stable for multiple rounds of infection; marker-cassette deletion revertants appeared after several replication rounds...

Autophagy Facilitates Salmonella Replication in HeLa Cells

Science.gov (United States)

Yu, Hong B.; Croxen, Matthew A.; Marchiando, Amanda M.; Ferreira, Rosana B. R.; Cadwell, Ken; Foster, Leonard J.; Finlay, B. Brett

2014-01-01

ABSTRACT Autophagy is a process whereby a double-membrane structure (autophagosome) engulfs unnecessary cytosolic proteins, organelles, and invading pathogens and delivers them to the lysosome for degradation. We examined the fate of cytosolic Salmonella targeted by autophagy and found that autophagy-targeted Salmonella present in the cytosol of HeLa cells correlates with intracellular bacterial replication. Real-time analyses revealed that a subset of cytosolic Salmonella extensively associates with autophagy components p62 and/or LC3 and replicates quickly, whereas intravacuolar Salmonella shows no or very limited association with p62 or LC3 and replicates much more slowly. Replication of cytosolic Salmonella in HeLa cells is significantly decreased when autophagy components are depleted. Eventually, hyperreplication of cytosolic Salmonella potentiates cell detachment, facilitating the dissemination of Salmonella to neighboring cells. We propose that Salmonella benefits from autophagy for its cytosolic replication in HeLa cells. PMID:24618251

Pleiotropic Meta-Analyses of Longitudinal Studies Discover Novel Genetic Variants Associated with Age-Related Diseases

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Liang He

2016-10-01

Full Text Available Age-related diseases may result from shared biological mechanisms in intrinsic processes of aging. Genetic effects on age-related diseases are often modulated by environmental factors due to their little contribution to fitness or are mediated through certain endophenotypes. Identification of genetic variants with pleiotropic effects on both common complex diseases and endophenotypes may reveal potential conflicting evolutionary pressures and deliver new insights into shared genetic contribution to healthspan and lifespan. Here, we performed pleiotropic meta-analyses of genetic variants using five NIH-funded datasets by integrating univariate summary statistics for age-related diseases and endophenotypes. We investigated three groups of traits: (1 endophenotypes such as blood glucose, blood pressure, lipids, hematocrit, and body mass index, (2 time-to-event outcomes such as the age-at-onset of diabetes mellitus (DM, cancer, cardiovascular diseases (CVDs and neurodegenerative diseases (NDs, and (3 both combined. In addition to replicating previous findings, we identify seven novel genome-wide significant loci (< 5e-08, out of which five are low-frequency variants. Specifically, from Group 2, we find rs7632505 on 3q21.1 in SEMA5B, rs460976 on 21q22.3 (1 kb from TMPRSS2 and rs12420422 on 11q24.1 predominantly associated with a variety of CVDs, rs4905014 in ITPK1 associated with stroke and heart failure, rs7081476 on 10p12.1 in ANKRD26 associated with multiple diseases including DM, CVDs, and NDs. From Group 3, we find rs8082812 on 18p11.22 and rs1869717 on 4q31.3 associated with both endophenotypes and CVDs. Our follow-up analyses show that rs7632505, rs4905014, and rs8082812 have age-dependent effects on coronary heart disease or stroke. Functional annotation suggests that most of these SNPs are within regulatory regions or DNase clusters and in linkage disequilibrium with expression quantitative trait loci, implying their potential regulatory

Genetic pleiotropy explains associations between musical auditory discrimination and intelligence.

Science.gov (United States)

Mosing, Miriam A; Pedersen, Nancy L; Madison, Guy; Ullén, Fredrik

2014-01-01

Musical aptitude is commonly measured using tasks that involve discrimination of different types of musical auditory stimuli. Performance on such different discrimination tasks correlates positively with each other and with intelligence. However, no study to date has explored these associations using a genetically informative sample to estimate underlying genetic and environmental influences. In the present study, a large sample of Swedish twins (N = 10,500) was used to investigate the genetic architecture of the associations between intelligence and performance on three musical auditory discrimination tasks (rhythm, melody and pitch). Phenotypic correlations between the tasks ranged between 0.23 and 0.42 (Pearson r values). Genetic modelling showed that the covariation between the variables could be explained by shared genetic influences. Neither shared, nor non-shared environment had a significant effect on the associations. Good fit was obtained with a two-factor model where one underlying shared genetic factor explained all the covariation between the musical discrimination tasks and IQ, and a second genetic factor explained variance exclusively shared among the discrimination tasks. The results suggest that positive correlations among musical aptitudes result from both genes with broad effects on cognition, and genes with potentially more specific influences on auditory functions.

Smoking and caffeine consumption: a genetic analysis of their association.

Science.gov (United States)

Treur, Jorien L; Taylor, Amy E; Ware, Jennifer J; Nivard, Michel G; Neale, Michael C; McMahon, George; Hottenga, Jouke-Jan; Baselmans, Bart M L; Boomsma, Dorret I; Munafò, Marcus R; Vink, Jacqueline M

2017-07-01

Smoking and caffeine consumption show a strong positive correlation, but the mechanism underlying this association is unclear. Explanations include shared genetic/environmental factors or causal effects. This study employed three methods to investigate the association between smoking and caffeine. First, bivariate genetic models were applied to data of 10 368 twins from the Netherlands Twin Register in order to estimate genetic and environmental correlations between smoking and caffeine use. Second, from the summary statistics of meta-analyses of genome-wide association studies on smoking and caffeine, the genetic correlation was calculated by LD-score regression. Third, causal effects were tested using Mendelian randomization analysis in 6605 Netherlands Twin Register participants and 5714 women from the Avon Longitudinal Study of Parents and Children. Through twin modelling, a genetic correlation of r0.47 and an environmental correlation of r0.30 were estimated between current smoking (yes/no) and coffee use (high/low). Between current smoking and total caffeine use, this was r0.44 and r0.00, respectively. LD-score regression also indicated sizeable genetic correlations between smoking and coffee use (r0.44 between smoking heaviness and cups of coffee per day, r0.28 between smoking initiation and coffee use and r0.25 between smoking persistence and coffee use). Consistent with the relatively high genetic correlations and lower environmental correlations, Mendelian randomization provided no evidence for causal effects of smoking on caffeine or vice versa. Genetic factors thus explain most of the association between smoking and caffeine consumption. These findings suggest that quitting smoking may be more difficult for heavy caffeine consumers, given their genetic susceptibility. © 2016 The Authors.Addiction Biology published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.

Using the longest significance run to estimate region-specific p-values in genetic association mapping studies

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Yang Hsin-Chou

2008-05-01

Full Text Available Abstract Background Association testing is a powerful tool for identifying disease susceptibility genes underlying complex diseases. Technological advances have yielded a dramatic increase in the density of available genetic markers, necessitating an increase in the number of association tests required for the analysis of disease susceptibility genes. As such, multiple-tests corrections have become a critical issue. However the conventional statistical corrections on locus-specific multiple tests usually result in lower power as the number of markers increases. Alternatively, we propose here the application of the longest significant run (LSR method to estimate a region-specific p-value to provide an index for the most likely candidate region. Results An advantage of the LSR method relative to procedures based on genotypic data is that only p-value data are needed and hence can be applied extensively to different study designs. In this study the proposed LSR method was compared with commonly used methods such as Bonferroni's method and FDR controlling method. We found that while all methods provide good control over false positive rate, LSR has much better power and false discovery rate. In the authentic analysis on psoriasis and asthma disease data, the LSR method successfully identified important candidate regions and replicated the results of previous association studies. Conclusion The proposed LSR method provides an efficient exploratory tool for the analysis of sequences of dense genetic markers. Our results show that the LSR method has better power and lower false discovery rate comparing with the locus-specific multiple tests.

Inter-Fork Strand Annealing causes genomic deletions during the termination of DNA replication.

Science.gov (United States)

Morrow, Carl A; Nguyen, Michael O; Fower, Andrew; Wong, Io Nam; Osman, Fekret; Bryer, Claire; Whitby, Matthew C

2017-06-06

Problems that arise during DNA replication can drive genomic alterations that are instrumental in the development of cancers and many human genetic disorders. Replication fork barriers are a commonly encountered problem, which can cause fork collapse and act as hotspots for replication termination. Collapsed forks can be rescued by homologous recombination, which restarts replication. However, replication restart is relatively slow and, therefore, replication termination may frequently occur by an active fork converging on a collapsed fork. We find that this type of non-canonical fork convergence in fission yeast is prone to trigger deletions between repetitive DNA sequences via a mechanism we call Inter-Fork Strand Annealing (IFSA) that depends on the recombination proteins Rad52, Exo1 and Mus81, and is countered by the FANCM-related DNA helicase Fml1. Based on our findings, we propose that IFSA is a potential threat to genomic stability in eukaryotes.

Genetic and educational assortative mating among US adults.

Science.gov (United States)

Domingue, Benjamin W; Fletcher, Jason; Conley, Dalton; Boardman, Jason D

2014-06-03

Understanding the social and biological mechanisms that lead to homogamy (similar individuals marrying one another) has been a long-standing issue across many fields of scientific inquiry. Using a nationally representative sample of non-Hispanic white US adults from the Health and Retirement Study and information from 1.7 million single-nucleotide polymorphisms, we compare genetic similarity among married couples to noncoupled pairs in the population. We provide evidence for genetic assortative mating in this population but the strength of this association is substantially smaller than the strength of educational assortative mating in the same sample. Furthermore, genetic similarity explains at most 10% of the assortative mating by education levels. Results are replicated using comparable data from the Framingham Heart Study.

VAV1 and BAFF, via NFκB pathway, are genetic risk factors for myasthenia gravis

DEFF Research Database (Denmark)

Avidan, Nili; Le Panse, Rozen; Harbo, Hanne F

2014-01-01

OBJECTIVE: To identify novel genetic loci that predispose to early-onset myasthenia gravis (EOMG) applying a two-stage association study, exploration, and replication strategy. METHODS: Thirty-four loci and one confirmation loci, human leukocyte antigen (HLA)-DRA, were selected as candidate genes...

Inbred or Outbred? Genetic Diversity in Laboratory Rodent Colonies

Science.gov (United States)

Brekke, Thomas D.; Steele, Katherine A.; Mulley, John F.

2017-01-01

Nonmodel rodents are widely used as subjects for both basic and applied biological research, but the genetic diversity of the study individuals is rarely quantified. University-housed colonies tend to be small and subject to founder effects and genetic drift; so they may be highly inbred or show substantial genetic divergence from other colonies, even those derived from the same source. Disregard for the levels of genetic diversity in an animal colony may result in a failure to replicate results if a different colony is used to repeat an experiment, as different colonies may have fixed alternative variants. Here we use high throughput sequencing to demonstrate genetic divergence in three isolated colonies of Mongolian gerbil (Meriones unguiculatus) even though they were all established recently from the same source. We also show that genetic diversity in allegedly “outbred” colonies of nonmodel rodents (gerbils, hamsters, house mice, deer mice, and rats) varies considerably from nearly no segregating diversity to very high levels of polymorphism. We conclude that genetic divergence in isolated colonies may play an important role in the “replication crisis.” In a more positive light, divergent rodent colonies represent an opportunity to leverage genetically distinct individuals in genetic crossing experiments. In sum, awareness of the genetic diversity of an animal colony is paramount as it allows researchers to properly replicate experiments and also to capitalize on other genetically distinct individuals to explore the genetic basis of a trait. PMID:29242387

Genetic Variations Involved in Vitamin E Status

Directory of Open Access Journals (Sweden)

Patrick Borel

2016-12-01

Full Text Available Vitamin E (VE is the generic term for four tocopherols and four tocotrienols that exhibit the biological activity of α-tocopherol. VE status, which is usually estimated by measuring fasting blood VE concentration, is affected by numerous factors, such as dietary VE intake, VE absorption efficiency, and VE catabolism. Several of these factors are in turn modulated by genetic variations in genes encoding proteins involved in these factors. To identify these genetic variations, two strategies have been used: genome-wide association studies and candidate gene association studies. Each of these strategies has its advantages and its drawbacks, nevertheless they have allowed us to identify a list of single nucleotide polymorphisms associated with fasting blood VE concentration and α-tocopherol bioavailability. However, much work remains to be done to identify, and to replicate in different populations, all the single nucleotide polymorphisms involved, to assess the possible involvement of other kind of genetic variations, e.g., copy number variants and epigenetic modifications, in order to establish a reliable list of genetic variations that will allow us to predict the VE status of an individual by knowing their genotype in these genetic variations. Yet, the potential usefulness of this area of research is exciting with regard to personalized nutrition and for future clinical trials dedicated to assessing the biological effects of the various isoforms of VE.

Identification of Novel Genetic Loci Associated with Thyroid Peroxidase Antibodies and Clinical Thyroid Disease

Science.gov (United States)

Teumer, Alexander; Brown, Suzanne J.; Jensen, Richard A.; Rawal, Rajesh; Roef, Greet L.; Plantinga, Theo S.; Vermeulen, Sita H.; Lahti, Jari; Simmonds, Matthew J.; Husemoen, Lise Lotte N.; Freathy, Rachel M.; Shields, Beverley M.; Pietzner, Diana; Nagy, Rebecca; Broer, Linda; Chaker, Layal; Korevaar, Tim I. M.; Plia, Maria Grazia; Sala, Cinzia; Völker, Uwe; Richards, J. Brent; Sweep, Fred C.; Gieger, Christian; Corre, Tanguy; Kajantie, Eero; Thuesen, Betina; Taes, Youri E.; Visser, W. Edward; Hattersley, Andrew T.; Kratzsch, Jürgen; Hamilton, Alexander; Li, Wei; Homuth, Georg; Lobina, Monia; Mariotti, Stefano; Soranzo, Nicole; Cocca, Massimiliano; Nauck, Matthias; Spielhagen, Christin; Ross, Alec; Arnold, Alice; van de Bunt, Martijn; Liyanarachchi, Sandya; Heier, Margit; Grabe, Hans Jörgen; Masciullo, Corrado; Galesloot, Tessel E.; Lim, Ee M.; Reischl, Eva; Leedman, Peter J.; Lai, Sandra; Delitala, Alessandro; Bremner, Alexandra P.; Philips, David I. W.; Beilby, John P.; Mulas, Antonella; Vocale, Matteo; Abecasis, Goncalo; Forsen, Tom; James, Alan; Widen, Elisabeth; Hui, Jennie; Prokisch, Holger; Rietzschel, Ernst E.; Palotie, Aarno; Feddema, Peter; Fletcher, Stephen J.; Schramm, Katharina; Rotter, Jerome I.; Kluttig, Alexander; Radke, Dörte; Traglia, Michela; Surdulescu, Gabriela L.; He, Huiling; Franklyn, Jayne A.; Tiller, Daniel; Vaidya, Bijay; de Meyer, Tim; Jørgensen, Torben; Eriksson, Johan G.; O'Leary, Peter C.; Wichmann, Eric; Hermus, Ad R.; Psaty, Bruce M.; Ittermann, Till; Hofman, Albert; Bosi, Emanuele; Schlessinger, David; Wallaschofski, Henri; Pirastu, Nicola; Aulchenko, Yurii S.; de la Chapelle, Albert; Netea-Maier, Romana T.; Gough, Stephen C. L.; Meyer zu Schwabedissen, Henriette; Frayling, Timothy M.; Kaufman, Jean-Marc; Linneberg, Allan; Räikkönen, Katri; Smit, Johannes W. A.; Kiemeney, Lambertus A.; Rivadeneira, Fernando; Uitterlinden, André G.; Walsh, John P.; Meisinger, Christa; den Heijer, Martin; Visser, Theo J.; Spector, Timothy D.; Wilson, Scott G.; Völzke, Henry; Cappola, Anne; Toniolo, Daniela; Sanna, Serena; Naitza, Silvia; Peeters, Robin P.

2014-01-01

Autoimmune thyroid diseases (AITD) are common, affecting 2-5% of the general population. Individuals with positive thyroid peroxidase antibodies (TPOAbs) have an increased risk of autoimmune hypothyroidism (Hashimoto's thyroiditis), as well as autoimmune hyperthyroidism (Graves' disease). As the possible causative genes of TPOAbs and AITD remain largely unknown, we performed GWAS meta-analyses in 18,297 individuals for TPOAb-positivity (1769 TPOAb-positives and 16,528 TPOAb-negatives) and in 12,353 individuals for TPOAb serum levels, with replication in 8,990 individuals. Significant associations (Phyperthyroidism, goiter and thyroid cancer were studied. Individuals with a high genetic risk score had, besides an increased risk of TPOAb-positivity (OR: 2.18, 95% CI 1.68–2.81, P = 8.1×10−8), a higher risk of increased thyroid-stimulating hormone levels (OR: 1.51, 95% CI 1.26–1.82, P = 2.9×10−6), as well as a decreased risk of goiter (OR: 0.77, 95% CI 0.66–0.89, P = 6.5×10−4). The MAGI3 and BACH2 variants were associated with an increased risk of hyperthyroidism, which was replicated in an independent cohort of patients with Graves' disease (OR: 1.37, 95% CI 1.22–1.54, P = 1.2×10−7 and OR: 1.25, 95% CI 1.12–1.39, P = 6.2×10−5). The MAGI3 variant was also associated with an increased risk of hypothyroidism (OR: 1.57, 95% CI 1.18–2.10, P = 1.9×10−3). This first GWAS meta-analysis for TPOAbs identified five newly associated loci, three of which were also associated with clinical thyroid disease. With these markers we identified a large subgroup in the general population with a substantially increased risk of TPOAbs. The results provide insight into why individuals with thyroid autoimmunity do or do not eventually develop thyroid disease, and these markers may therefore predict which TPOAb-positives are particularly at risk of developing clinical thyroid dysfunction. PMID:24586183

Sterol Binding by the Tombusviral Replication Proteins Is Essential for Replication in Yeast and Plants.

Science.gov (United States)

Xu, Kai; Nagy, Peter D

2017-04-01

Membranous structures derived from various organelles are important for replication of plus-stranded RNA viruses. Although the important roles of co-opted host proteins in RNA virus replication have been appreciated for a decade, the equally important functions of cellular lipids in virus replication have been gaining full attention only recently. Previous work with Tomato bushy stunt tombusvirus (TBSV) in model host yeast has revealed essential roles for phosphatidylethanolamine and sterols in viral replication. To further our understanding of the role of sterols in tombusvirus replication, in this work we showed that the TBSV p33 and p92 replication proteins could bind to sterols in vitro The sterol binding by p33 is supported by cholesterol recognition/interaction amino acid consensus (CRAC) and CARC-like sequences within the two transmembrane domains of p33. Mutagenesis of the critical Y amino acids within the CRAC and CARC sequences blocked TBSV replication in yeast and plant cells. We also showed the enrichment of sterols in the detergent-resistant membrane (DRM) fractions obtained from yeast and plant cells replicating TBSV. The DRMs could support viral RNA synthesis on both the endogenous and exogenous templates. A lipidomic approach showed the lack of enhancement of sterol levels in yeast and plant cells replicating TBSV. The data support the notion that the TBSV replication proteins are associated with sterol-rich detergent-resistant membranes in yeast and plant cells. Together, the results obtained in this study and the previously published results support the local enrichment of sterols around the viral replication proteins that is critical for TBSV replication. IMPORTANCE One intriguing aspect of viral infections is their dependence on efficient subcellular assembly platforms serving replication, virion assembly, or virus egress via budding out of infected cells. These assembly platforms might involve sterol-rich membrane microdomains, which are

Regulation of adeno-associated virus DNA replication by the cellular TAF-I/set complex.

Science.gov (United States)

Pegoraro, Gianluca; Marcello, Alessandro; Myers, Michael P; Giacca, Mauro

2006-07-01

The Rep proteins of the adeno-associated virus (AAV) are required for viral replication in the presence of adenovirus helper functions and as yet poorly characterized cellular factors. In an attempt to identify such factors, we purified Flag-Rep68-interacting proteins from human cell lysates. Several polypeptides were identified by mass spectrometry, among which was ANP32B, a member of the acidic nuclear protein 32 family which takes part in the formation of the template-activating factor I/Set oncoprotein (TAF-I/Set) complex. The N terminus of Rep was found to specifically bind the acidic domain of ANP32B; through this interaction, Rep was also able to recruit other members of the TAF-I/Set complex, including the ANP32A protein and the histone chaperone TAF-I/Set. Further experiments revealed that silencing of ANP32A and ANP32B inhibited AAV replication, while overexpression of all of the components of the TAF-I/Set complex increased de novo AAV DNA synthesis in permissive cells. Besides being the first indication that the TAF-I/Set complex participates in wild-type AAV replication, these findings have important implications for the generation of recombinant AAV vectors since overexpression of the TAF-I/Set components was found to markedly increase viral vector production.

Meta-analysis of genome-wide association studies in African Americans provides insights into the genetic architecture of type 2 diabetes

DEFF Research Database (Denmark)

Ng, Maggie C Y; Shriner, Daniel; Chen, Brian H

2014-01-01

. In order to investigate the genetic architecture of T2D in African Americans, the MEta-analysis of type 2 DIabetes in African Americans (MEDIA) Consortium examined 17 GWAS on T2D comprising 8,284 cases and 15,543 controls in African Americans in stage 1 analysis. Single nucleotide polymorphisms (SNPs......) association analysis was conducted in each study under the additive model after adjustment for age, sex, study site, and principal components. Meta-analysis of approximately 2.6 million genotyped and imputed SNPs in all studies was conducted using an inverse variance-weighted fixed effect model. Replications...... for linkage disequilibrium, enabling fine mapping of causal variants in trans-ethnic meta-analysis studies....

Variants in the SP110 gene are associated with genetic susceptibility to tuberculosis in West Africa

Science.gov (United States)

Tosh, Kerrie; Campbell, Sarah J.; Fielding, Katherine; Sillah, Jackson; Bah, Boubacar; Gustafson, Per; Manneh, Kebba; Lisse, Ida; Sirugo, Giorgio; Bennett, Steve; Aaby, Peter; McAdam, Keith P. W. J.; Bah-Sow, Oumou; Lienhardt, Christian; Kramnik, Igor; Hill, Adrian V. S.

2006-01-01

The sst1 locus has been identified in a mouse model to control resistance and susceptibility of Mycobacterium tuberculosis infection. Subsequent studies have now identified Ipr1 (intracellular pathogen resistance 1) to be the gene responsible. Ipr1 is encoded within the sst1 locus and is expressed in the tuberculosis lung lesions and macrophages of sst1-resistant, but not sst1-susceptible mice. We have therefore examined the closest human homologue of Ipr1, SP110, for its ability to control susceptibility to M. tuberculosis infection in humans. In a study of families from The Gambia we have identified three polymorphisms that are associated with disease. On examination of additional families from Guinea-Bissau and the Republic of Guinea, two of these associations were independently replicated. These variants are in strong linkage disequilibrium with each other and lie within a 31-kb block of low haplotypic diversity, suggesting that a polymorphism within this region has a role in genetic susceptibility to tuberculosis in humans. PMID:16803959

Association of three genetic loci with uric acid concentration and risk of gout: a genome-wide association study.

Science.gov (United States)

Dehghan, Abbas; Köttgen, Anna; Yang, Qiong; Hwang, Shih-Jen; Kao, Wh Linda; Rivadeneira, Fernando; Boerwinkle, Eric; Levy, Daniel; Hofman, Albert; Astor, Brad C; Benjamin, Emelia J; van Duijn, Cornelia M; Witteman, Jacqueline C; Coresh, Josef; Fox, Caroline S

2008-12-06

Hyperuricaemia, a highly heritable trait, is a key risk factor for gout. We aimed to identify novel genes associated with serum uric acid concentration and gout. Genome-wide association studies were done for serum uric acid in 7699 participants in the Framingham cohort and in 4148 participants in the Rotterdam cohort. Genome-wide significant single nucleotide polymorphisms (SNPs) were replicated in white (n=11 024) and black (n=3843) individuals who took part in the study of Atherosclerosis Risk in Communities (ARIC). The SNPs that reached genome-wide significant association with uric acid in either the Framingham cohort (pgout. The results obtained in white participants were combined using meta-analysis. Three loci in the Framingham cohort and two in the Rotterdam cohort showed genome-wide association with uric acid. Top SNPs in each locus were: missense rs16890979 in SLC2A9 (p=7.0 x 10(-168) and 2.9 x 10(-18) for white and black participants, respectively); missense rs2231142 in ABCG2 (p=2.5 x 10(-60) and 9.8 x 10(-4)), and rs1165205 in SLC17A3 (p=3.3 x 10(-26) and 0.33). All SNPs were direction-consistent with gout in white participants: rs16890979 (OR 0.59 per T allele, 95% CI 0.52-0.68, p=7.0 x 10(-14)), rs2231142 (1.74, 1.51-1.99, p=3.3 x 10(-15)), and rs1165205 (0.85, 0.77-0.94, p=0.002). In black participants of the ARIC study, rs2231142 was direction-consistent with gout (1.71, 1.06-2.77, p=0.028). An additive genetic risk score of high-risk alleles at the three loci showed graded associations with uric acid (272-351 mumol/L in the Framingham cohort, 269-386 mumol/L in the Rotterdam cohort, and 303-426 mumol/L in white participants of the ARIC study) and gout (frequency 2-13% in the Framingham cohort, 2-8% in the Rotterdam cohort, and 1-18% in white participants in the ARIC study). We identified three genetic loci associated with uric acid concentration and gout. A score based on genes with a putative role in renal urate handling showed a substantial risk

Rv0004 is a new essential member of the mycobacterial DNA replication machinery.

Science.gov (United States)

Mann, Katherine M; Huang, Deborah L; Hooppaw, Anna J; Logsdon, Michelle M; Richardson, Kirill; Lee, Hark Joon; Kimmey, Jacqueline M; Aldridge, Bree B; Stallings, Christina L

2017-11-01

DNA replication is fundamental for life, yet a detailed understanding of bacterial DNA replication is limited outside the organisms Escherichia coli and Bacillus subtilis. Many bacteria, including mycobacteria, encode no identified homologs of helicase loaders or regulators of the initiator protein DnaA, despite these factors being essential for DNA replication in E. coli and B. subtilis. In this study we discover that a previously uncharacterized protein, Rv0004, from the human pathogen Mycobacterium tuberculosis is essential for bacterial viability and that depletion of Rv0004 leads to a block in cell cycle progression. Using a combination of genetic and biochemical approaches, we found that Rv0004 has a role in DNA replication, interacts with DNA and the replicative helicase DnaB, and affects DnaB-DnaA complex formation. We also identify a conserved domain in Rv0004 that is predicted to structurally resemble the N-terminal protein-protein interaction domain of DnaA. Mutation of a single conserved tryptophan within Rv0004's DnaA N-terminal-like domain leads to phenotypes similar to those observed upon Rv0004 depletion and can affect the association of Rv0004 with DnaB. In addition, using live cell imaging during depletion of Rv0004, we have uncovered a previously unappreciated role for DNA replication in coordinating mycobacterial cell division and cell size. Together, our data support that Rv0004 encodes a homolog of the recently identified DciA family of proteins found in most bacteria that lack the DnaC-DnaI helicase loaders in E. coli and B. subtilis. Therefore, the mechanisms of Rv0004 elucidated here likely apply to other DciA homologs and reveal insight into the diversity of bacterial strategies in even the most conserved biological processes.

Nuclear safety aspects of exported replicate nuclear power plants and associated problems

International Nuclear Information System (INIS)

Kern, H.G.

1978-01-01

The standardization of the export nuclear power plant is being pursued with the concept of replication. This concept entails using another exported Nuclear Power Plant (NPP) as the base design and adapting it to a new site. The general ground rule applied to this concept is upgrading the design where necessary and duplicating the design where it is superior. Such continuous improvement will result in a standard export NPP that incorporates design features which will make it essentially acceptable for any suitable site. The advantages of replication are, therefore, boundless. However, the replication mode requires superior design control by the engineer to assure that only improvements alter the base design. With this concept, the replicating engineer is essentially assigned the responsiblity of safeguarding the standard export plant design. He is delegated the task of filtering the design such that only the conservative aspects prevail. Tight control of design changes via properly administered procedures is necessary to assure that no unforeseen compromises are made in designs which have already achieved optimization. Techniques to accomplish successful replication include, among others, the use of PCNs, system cognizant engineers, design verfication review, and the participation of all engineering disciplines in the development of the project schedule. (author)

Genetic and Non-genetic Factors Associated With Constipation in Cancer Patients Receiving Opioids

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Laugsand, Eivor A; Skorpen, Frank; Kaasa, Stein; Sabatowski, Rainer; Strasser, Florian; Fayers, Peter; Klepstad, Pål

2015-01-01

Objectives: To examine whether the inter-individual variation in constipation among patients receiving opioids for cancer pain is associated with genetic or non-genetic factors. Methods: Cancer patients receiving opioids were included from 17 centers in 11 European countries. Intensity of constipation was reported by 1,568 patients on a four-point categorical scale. Non-genetic factors were included as covariates in stratified regression analyses on the association between constipation and 75 single-nucleotide polymorphisms (SNPs) within 15 candidate genes related to opioid- or constipation-signaling pathways (HTR3E, HTR4, HTR2A, TPH1, ADRA2A, CHRM3, TACR1, CCKAR, KIT, ARRB2, GHRL, ABCB1, COMT, OPRM1, and OPRD1). Results: The non-genetic factors significantly associated with constipation were type of laxative, mobility and place of care among patients receiving laxatives (N=806), in addition to Karnofsky performance status and presence of metastases among patients not receiving laxatives (N=762) (P<0.01). Age, gender, body mass index, cancer diagnosis, time on opioids, opioid dose, and type of opioid did not contribute to the inter-individual differences in constipation. Five SNPs, rs1800532 in TPH1, rs1799971 in OPRM1, rs4437575 in ABCB1, rs10802789 in CHRM3, and rs2020917 in COMT were associated with constipation (P<0.01). Only rs2020917 in COMT passed the Benjamini–Hochberg criterion for a 10% false discovery rate. Conclusions: Type of laxative, mobility, hospitalization, Karnofsky performance status, presence of metastases, and five SNPs within TPH1, OPRM1, ABCB1, CHRM3, and COMT may contribute to the variability in constipation among cancer patients treated with opioids. Knowledge of these factors may help to develop new therapies and to identify patients needing a more individualized approach to treatment. PMID:26087058

In Vivo fitness associated with high virulence in a vertebrate virus is a complex trait regulated by host entry, replication, and shedding

Science.gov (United States)

Wargo, Andrew R.; Kurath, Gael

2011-01-01

The relationship between pathogen fitness and virulence is typically examined by quantifying only one or two pathogen fitness traits. More specifically, it is regularly assumed that within-host replication, as a precursor to transmission, is the driving force behind virulence. In reality, many traits contribute to pathogen fitness, and each trait could drive the evolution of virulence in different ways. Here, we independently quantified four viral infection cycle traits, namely, host entry, within-host replication, within-host coinfection fitness, and shedding, in vivo, in the vertebrate virus Infectious hematopoietic necrosis virus (IHNV). We examined how each of these stages of the viral infection cycle contributes to the fitness of IHNV genotypes that differ in virulence in rainbow trout. This enabled us to determine how infection cycle fitness traits are independently associated with virulence. We found that viral fitness was independently regulated by each of the traits examined, with the largest impact on fitness being provided by within-host replication. Furthermore, the more virulent of the two genotypes of IHNV we used had advantages in all of the traits quantified. Our results are thus congruent with the assumption that virulence and within-host replication are correlated but suggest that infection cycle fitness is complex and that replication is not the only trait associated with virulence.

Tus-Ter as a tool to study site-specific DNA replication perturbation in eukaryotes

DEFF Research Database (Denmark)

Larsen, Nicolai B; Hickson, Ian D; Mankouri, Hocine W

2014-01-01

The high-affinity binding of the Tus protein to specific 21-bp sequences, called Ter, causes site-specific, and polar, DNA replication fork arrest in E coli. The Tus-Ter complex serves to coordinate DNA replication with chromosome segregation in this organism. A number of recent and ongoing studies...... have demonstrated that Tus-Ter can be used as a heterologous tool to generate site-specific perturbation of DNA replication when reconstituted in eukaryotes. Here, we review these recent findings and explore the molecular mechanism by which Tus-Ter mediates replication fork (RF) arrest in the budding...... yeast, S. cerevisiae. We propose that Tus-Ter is a versatile, genetically tractable, and regulatable RF blocking system that can be utilized for disrupting DNA replication in a diverse range of host cells....

Tus-Ter as a tool to study site-specific DNA replication perturbation in eukaryotes.

Science.gov (United States)

Larsen, Nicolai B; Hickson, Ian D; Mankouri, Hocine W

2014-01-01

The high-affinity binding of the Tus protein to specific 21-bp sequences, called Ter, causes site-specific, and polar, DNA replication fork arrest in E coli. The Tus-Ter complex serves to coordinate DNA replication with chromosome segregation in this organism. A number of recent and ongoing studies have demonstrated that Tus-Ter can be used as a heterologous tool to generate site-specific perturbation of DNA replication when reconstituted in eukaryotes. Here, we review these recent findings and explore the molecular mechanism by which Tus-Ter mediates replication fork (RF) arrest in the budding yeast, S. cerevisiae. We propose that Tus-Ter is a versatile, genetically tractable, and regulatable RF blocking system that can be utilized for disrupting DNA replication in a diverse range of host cells.

Genetic assessment of age-associated Alzheimer disease risk: Development and validation of a polygenic hazard score.

Directory of Open Access Journals (Sweden)

Rahul S Desikan

2017-03-01

Full Text Available Identifying individuals at risk for developing Alzheimer disease (AD is of utmost importance. Although genetic studies have identified AD-associated SNPs in APOE and other genes, genetic information has not been integrated into an epidemiological framework for risk prediction.Using genotype data from 17,008 AD cases and 37,154 controls from the International Genomics of Alzheimer's Project (IGAP Stage 1, we identified AD-associated SNPs (at p < 10-5. We then integrated these AD-associated SNPs into a Cox proportional hazard model using genotype data from a subset of 6,409 AD patients and 9,386 older controls from Phase 1 of the Alzheimer's Disease Genetics Consortium (ADGC, providing a polygenic hazard score (PHS for each participant. By combining population-based incidence rates and the genotype-derived PHS for each individual, we derived estimates of instantaneous risk for developing AD, based on genotype and age, and tested replication in multiple independent cohorts (ADGC Phase 2, National Institute on Aging Alzheimer's Disease Center [NIA ADC], and Alzheimer's Disease Neuroimaging Initiative [ADNI], total n = 20,680. Within the ADGC Phase 1 cohort, individuals in the highest PHS quartile developed AD at a considerably lower age and had the highest yearly AD incidence rate. Among APOE ε3/3 individuals, the PHS modified expected age of AD onset by more than 10 y between the lowest and highest deciles (hazard ratio 3.34, 95% CI 2.62-4.24, p = 1.0 × 10-22. In independent cohorts, the PHS strongly predicted empirical age of AD onset (ADGC Phase 2, r = 0.90, p = 1.1 × 10-26 and longitudinal progression from normal aging to AD (NIA ADC, Cochran-Armitage trend test, p = 1.5 × 10-10, and was associated with neuropathology (NIA ADC, Braak stage of neurofibrillary tangles, p = 3.9 × 10-6, and Consortium to Establish a Registry for Alzheimer's Disease score for neuritic plaques, p = 6.8 × 10-6 and in vivo markers of AD neurodegeneration (ADNI

Genetics and Early Detection in Idiopathic Pulmonary Fibrosis

Science.gov (United States)

Putman, Rachel K.; Rosas, Ivan O.

2014-01-01

Genetic studies hold promise in helping to identify patients with early idiopathic pulmonary fibrosis (IPF). Recent studies using chest computed tomograms (CTs) in smokers and in the general population have demonstrated that imaging abnormalities suggestive of an early stage of pulmonary fibrosis are not uncommon and are associated with respiratory symptoms, physical examination abnormalities, and physiologic decrements expected, but less severe than those noted in patients with IPF. Similarly, recent genetic studies have demonstrated strong and replicable associations between a common promoter polymorphism in the mucin 5B gene (MUC5B) and both IPF and the presence of abnormal imaging findings in the general population. Despite these findings, it is important to note that the definition of early-stage IPF remains unclear, limited data exist to definitively connect abnormal imaging findings to IPF, and genetic studies assessing early-stage pulmonary fibrosis remain in their infancy. In this perspective we provide updated information on interstitial lung abnormalities and their connection to IPF. We summarize information on the genetics of pulmonary fibrosis by focusing on the recent genetic findings of MUC5B. Finally, we discuss the implications of these findings and suggest a roadmap for the use of genetics in the detection of early IPF. PMID:24547893

Persistence of transmitted HIV-1 drug resistance mutations associated with fitness costs and viral genetic backgrounds.

Directory of Open Access Journals (Sweden)

Wan-Lin Yang

2015-03-01

Full Text Available Transmission of drug-resistant pathogens presents an almost-universal challenge for fighting infectious diseases. Transmitted drug resistance mutations (TDRM can persist in the absence of drugs for considerable time. It is generally believed that differential TDRM-persistence is caused, at least partially, by variations in TDRM-fitness-costs. However, in vivo epidemiological evidence for the impact of fitness costs on TDRM-persistence is rare. Here, we studied the persistence of TDRM in HIV-1 using longitudinally-sampled nucleotide sequences from the Swiss-HIV-Cohort-Study (SHCS. All treatment-naïve individuals with TDRM at baseline were included. Persistence of TDRM was quantified via reversion rates (RR determined with interval-censored survival models. Fitness costs of TDRM were estimated in the genetic background in which they occurred using a previously published and validated machine-learning algorithm (based on in vitro replicative capacities and were included in the survival models as explanatory variables. In 857 sequential samples from 168 treatment-naïve patients, 17 TDRM were analyzed. RR varied substantially and ranged from 174.0/100-person-years;CI=[51.4, 588.8] (for 184V to 2.7/100-person-years;[0.7, 10.9] (for 215D. RR increased significantly with fitness cost (increase by 1.6[1.3,2.0] per standard deviation of fitness costs. When subdividing fitness costs into the average fitness cost of a given mutation and the deviation from the average fitness cost of a mutation in a given genetic background, we found that both components were significantly associated with reversion-rates. Our results show that the substantial variations of TDRM persistence in the absence of drugs are associated with fitness-cost differences both among mutations and among different genetic backgrounds for the same mutation.

Replication of 13q31.1 Association in Nonsyndromic Cleft Lip with Cleft Palate in Europeans

Science.gov (United States)

Cooper, Margaret E.; Butali, Azeez; Standley, Jennifer; Rigdon, Jennifer; Suzuki1, Satoshi; Gongorjav, Ayana; Shonkhuuz, T. Enkhtur; Natsume, Nagato; Shi, Bing; Marazita, Mary L.; Murray, Jeffrey C.

2015-01-01

Genome wide association (GWA) studies have successfully identified at least a dozen loci associated with orofacial clefts. However, these signals may be unique to specific populations and require replication to validate and extend findings as a prelude to etiologic SNP discovery. We attempted to replicate the findings of a recent meta-analysis of orofacial cleft GWA studies using four different ancestral populations. We studied 946 pedigrees (3436 persons) of European (US white and Danish) and Asian (Japanese and Mongolian) origin. We genotyped six SNPs which represented the most significant P value associations identified in published studies: rs742071 (1p36), rs7590268 (2p21), rs7632427 (3p11.1), rs12543318 (8q21.3), rs8001641 (13q31.1) and rs7179658 (15q22.2). We directly sequenced three non-coding conserved regions 200kb downstream of SPRY2 in 713 cases, 438 controls, and 485 trios from the US, Mongolia, and the Philippines. We found rs8001641 to be significantly associated with cleft lip with cleft palate (NSCLP) in Europeans (p-value=4 × 10−5, ORtransmission=1.86 with 95% confidence interval: 1.38-2.52). We also found several novel sequence variants in the conserved regions in Asian and European samples, which may help to localize common variants contributing directly to the risk for NSCLP. This study confirms the prior association between rs8001641 and NSCLP in European populations. PMID:25786657

New Sequence Variants in HLA Class II/III Region Associated with Susceptibility to Knee Osteoarthritis Identified by Genome-Wide Association Study

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Nakajima, Masahiro; Takahashi, Atsushi; Kou, Ikuyo; Rodriguez-Fontenla, Cristina; Gomez-Reino, Juan J.; Furuichi, Tatsuya; Dai, Jin; Sudo, Akihiro; Uchida, Atsumasa; Fukui, Naoshi; Kubo, Michiaki; Kamatani, Naoyuki; Tsunoda, Tatsuhiko; Malizos, Konstantinos N.; Tsezou, Aspasia; Gonzalez, Antonio; Nakamura, Yusuke; Ikegawa, Shiro

2010-01-01

Osteoarthritis (OA) is a common disease that has a definite genetic component. Only a few OA susceptibility genes that have definite functional evidence and replication of association have been reported, however. Through a genome-wide association study and a replication using a total of ∼4,800 Japanese subjects, we identified two single nucleotide polymorphisms (SNPs) (rs7775228 and rs10947262) associated with susceptibility to knee OA. The two SNPs were in a region containing HLA class II/III genes and their association reached genome-wide significance (combined P = 2.43×10−8 for rs7775228 and 6.73×10−8 for rs10947262). Our results suggest that immunologic mechanism is implicated in the etiology of OA. PMID:20305777

Identification of novel risk genes associated with type 1 diabetes mellitus using a genome-wide gene-based association analysis.

Science.gov (United States)

Qiu, Ying-Hua; Deng, Fei-Yan; Li, Min-Jing; Lei, Shu-Feng

2014-11-01

Type 1 diabetes mellitus is a serious disorder characterized by destruction of pancreatic β-cells, culminating in absolute insulin deficiency. Genetic factors contribute to the susceptibility of type 1 diabetes mellitus. The aim of the present study was to identify more susceptibility genes of type 1 diabetes mellitus. We carried out an initial gene-based genome-wide association study in a total of 4,075 type 1 diabetes mellitus cases and 2,604 controls by using the Gene-based Association Test using Extended Simes procedure. Furthermore, we carried out replication studies, differential expression analysis and functional annotation clustering analysis to support the significance of the identified susceptibility genes. We identified 452 genes associated with type 1 diabetes mellitus, even after adapting the genome-wide threshold for significance (P diabetes mellitus, which were ignored in single-nucleotide polymorphism-based association analysis and were not previously reported. We found that 53 genes have supportive evidence from replication studies and/or differential expression studies. In particular, seven genes including four non-human leukocyte antigen (HLA) genes (RASIP1, STRN4, BCAR1 and MYL2) are replicated in at least one independent population and also differentially expressed in peripheral blood mononuclear cells or monocytes. Furthermore, the associated genes tend to enrich in immune-related pathways or Gene Ontology project terms. The present results suggest the high power of gene-based association analysis in detecting disease-susceptibility genes. Our findings provide more insights into the genetic basis of type 1 diabetes mellitus.

Preimplantation genetic diagnosis associated to Duchenne muscular dystrophy.

Science.gov (United States)

Bianco, Bianca; Christofolini, Denise Maria; Conceição, Gabriel Seixas; Barbosa, Caio Parente

2017-01-01

Duchenne muscular dystrophy is the most common muscle disease found in male children. Currently, there is no effective therapy available for Duchenne muscular dystrophy patients. Therefore, it is essential to make a prenatal diagnosis and provide genetic counseling to reduce the birth of such boys. We report a case of preimplantation genetic diagnosis associated with Duchenne muscular dystrophy. The couple E.P.R., 38-year-old, symptomatic patient heterozygous for a 2 to 47 exon deletion mutation in DMD gene and G.T.S., 39-year-old, sought genetic counseling about preimplantation genetic diagnosis process. They have had a 6-year-old son who died due to Duchenne muscular dystrophy complications. The couple underwent four cycles of intracytoplasmic sperm injection (ICSI) and eight embryos biopsies were analyzed by polymerase chain reaction (PCR) for specific mutation analysis, followed by microarray-based comparative genomic hybridisation (array CGH) for aneuploidy analysis. Preimplantation genetic diagnosis revealed that two embryos had inherited the maternal DMD gene mutation, one embryo had a chromosomal alteration and five embryos were normal. One blastocyst was transferred and resulted in successful pregnancy. The other embryos remain vitrified. We concluded that embryo analysis using associated techniques of PCR and array CGH seems to be safe for embryo selection in cases of X-linked disorders, such as Duchenne muscular dystrophy.

Distributional Replication

OpenAIRE

Beare, Brendan K.

2009-01-01

Suppose that X and Y are random variables. We define a replicating function to be a function f such that f(X) and Y have the same distribution. In general, the set of replicating functions for a given pair of random variables may be infinite. Suppose we have some objective function, or cost function, defined over the set of replicating functions, and we seek to estimate the replicating function with the lowest cost. We develop an approach to estimating the cheapest replicating function that i...

A conserved helicase processivity factor is needed for conjugation and replication of an integrative and conjugative element.

Directory of Open Access Journals (Sweden)

Jacob Thomas

Full Text Available Integrative and conjugative elements (ICEs are agents of horizontal gene transfer and have major roles in evolution and acquisition of new traits, including antibiotic resistances. ICEs are found integrated in a host chromosome and can excise and transfer to recipient bacteria via conjugation. Conjugation involves nicking of the ICE origin of transfer (oriT by the ICE-encoded relaxase and transfer of the nicked single strand of ICE DNA. For ICEBs1 of Bacillus subtilis, nicking of oriT by the ICEBs1 relaxase NicK also initiates rolling circle replication. This autonomous replication of ICEBs1 is critical for stability of the excised element in growing cells. We found a conserved and previously uncharacterized ICE gene that is required for conjugation and replication of ICEBs1. Our results indicate that this gene, helP (formerly ydcP, encodes a helicase processivity factor that enables the host-encoded helicase PcrA to unwind the double-stranded ICEBs1 DNA. HelP was required for both conjugation and replication of ICEBs1, and HelP and NicK were the only ICEBs1 proteins needed for replication from ICEBs1 oriT. Using chromatin immunoprecipitation, we measured association of HelP, NicK, PcrA, and the host-encoded single-strand DNA binding protein Ssb with ICEBs1. We found that NicK was required for association of HelP and PcrA with ICEBs1 DNA. HelP was required for association of PcrA and Ssb with ICEBs1 regions distal, but not proximal, to oriT, indicating that PcrA needs HelP to progress beyond nicked oriT and unwind ICEBs1. In vitro, HelP directly stimulated the helicase activity of the PcrA homologue UvrD. Our findings demonstrate that HelP is a helicase processivity factor needed for efficient unwinding of ICEBs1 for conjugation and replication. Homologues of HelP and PcrA-type helicases are encoded on many known and putative ICEs. We propose that these factors are essential for ICE conjugation, replication, and genetic stability.

[Hypothetical link between endometriosis and xenobiotics-associated genetically modified food].

Science.gov (United States)

Aris, A; Paris, K

2010-12-01

Endometriosis is an oestrogen-dependent inflammatory disease affecting 10 % of reproductive-aged women. Often accompanied by chronic pelvic pain and infertility, endometriosis rigorously interferes with women's quality of life. Although the pathophysiology of endometriosis remains unclear, a growing body of evidence points to the implication of environmental toxicants. Over the last decade, an increase in the incidence of endometriosis has been reported and coincides with the introduction of genetically modified foods in our diet. Even though assessments of genetically modified food risk have not indicated any hazard on human health, xenobiotics-associated genetically modified food, such as pesticides residues and xenoproteins, could be harmful in the long-term. The "low-dose hypothesis", accumulation and biotransformation of pesticides-associated genetically modified food and the multiplied toxicity of pesticides-formulation adjuvants support this hypothesis. This review summarizes toxic effects (in vitro and on animal models) of some xenobiotics-associated genetically modified food, such as glyphosate and Cry1Ab protein, and extrapolates on their potential role in the pathophysiology of endometriosis. Their roles as immune toxicants, pro-oxidants, endocrine disruptors and epigenetic modulators are discussed. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Chromatin Immunoprecipitation of Replication Factors Moving with the Replication Fork

OpenAIRE

Rapp, Jordan B.; Ansbach, Alison B.; Noguchi, Chiaki; Noguchi, Eishi

2009-01-01

Replication of chromosomes involves a variety of replication proteins including DNA polymerases, DNA helicases, and other accessory factors. Many of these proteins are known to localize at replication forks and travel with them as components of the replisome complex. Other proteins do not move with replication forks but still play an essential role in DNA replication. Therefore, in order to understand the mechanisms of DNA replication and its controls, it is important to examine localization ...

Genetic variations in the DNA replication origins of human papillomavirus family correlate with their oncogenic potential.

Science.gov (United States)

Yilmaz, Gulden; Biswas-Fiss, Esther E; Biswas, Subhasis B

2018-04-01

Human papillomaviruses (HPVs) encompass a large family of viruses that range from benign to highly carcinogenic. The crucial differences between benign and carcinogenic types of HPV remain unknown, except that the two HPV types differ in the frequency of DNA replication. We have systematically analyzed the mechanism of HPV DNA replication initiation in low-risk and high-risk HPVs. Our results demonstrate that HPV-encoded E2 initiator protein and its four binding sites in the replication origin play pivotal roles in determining the destiny of the HPV-infected cell. We have identified strain-specific single nucleotide variations in E2 binding sites found only in the high-risk HPVs. We have demonstrated that these variations result in attenuated formation of the E2-DNA complex. E2 binding to these sites is linked to the activation of the DNA replication origin as well as initiation of DNA replication. Both electrophoretic mobility shift assay and atomic force microscopy studies demonstrated that binding of E2 from either low- or high-risk HPVs with variant binding sequences lacked multimeric E2-DNA complex formation in vitro. These results provided a molecular basis of differential DNA replication in the two types of HPVs and pointed to a correlation with the development of cancer. Copyright © 2017. Published by Elsevier B.V.

Negative self-referential processing is associated with genetic variation in the serotonin transporter-linked polymorphic region (5-HTTLPR): Evidence from two independent studies.

Science.gov (United States)

Dainer-Best, Justin; Disner, Seth G; McGeary, John E; Hamilton, Bethany J; Beevers, Christopher G

2018-01-01

The current research examined whether carriers of the short 5-HTTLPR allele (in SLC6A4), who have been shown to selectively attend to negative information, exhibit a bias towards negative self-referent processing. The self-referent encoding task (SRET) was used to measure self-referential processing of positive and negative adjectives. Ratcliff's diffusion model isolated and extracted decision-making components from SRET responses and reaction times. Across the initial (N = 183) and replication (N = 137) studies, results indicated that short 5-HTTLPR allele carriers more easily categorized negative adjectives as self-referential (i.e., higher drift rate). Further, drift rate was associated with recall of negative self-referential stimuli. Findings across both studies provide further evidence that genetic variation may contribute to the etiology of negatively biased processing of self-referent information. Large scale studies examining the genetic contributions to negative self-referent processing may be warranted.

Evaluation of seven common lipid associated loci in a large Indian sib pair study.

Science.gov (United States)

Rafiq, Sajjad; Venkata, Kranthi Kumar M; Gupta, Vipin; Vinay, D G; Spurgeon, Charles J; Parameshwaran, Smitha; Madana, Sandeep N; Kinra, Sanjay; Bowen, Liza; Timpson, Nicholas J; Smith, George Davey; Dudbridge, Frank; Prabhakaran, Dorairaj; Ben-Shlomo, Yoav; Reddy, K Srinath; Ebrahim, Shah; Chandak, Giriraj R

2012-11-14

Genome wide association studies (GWAS), mostly in Europeans have identified several common variants as associated with key lipid traits. Replication of these genetic effects in South Asian populations is important since it would suggest wider relevance for these findings. Given the rising prevalence of metabolic disorders and heart disease in the Indian sub-continent, these studies could be of future clinical relevance. We studied seven common variants associated with a variety of lipid traits in previous GWASs. The study sample comprised of 3178 sib-pairs recruited as participants for the Indian Migration Study (IMS). Associations with various lipid parameters and quantitative traits were analyzed using the Fulker genetic association model. We replicated five of the 7 main effect associations with p-values ranging from 0.03 to 1.97x10(-7). We identified particularly strong association signals at rs662799 in APOA5 (beta=0.18 s.d, p=1.97 x 10(-7)), rs10503669 in LPL (beta =-0.18 s.d, p=1.0 x 10(-4)) and rs780094 in GCKR (beta=0.11 s.d, p=0.001) loci in relation to triglycerides. In addition, the GCKR variant was also associated with total cholesterol (beta=0.11 s.d, p=3.9x10(-4)). We also replicated the association of rs562338 in APOB (p=0.03) and rs4775041 in LIPC (p=0.007) with LDL-cholesterol and HDL-cholesterol respectively. We report associations of five loci with various lipid traits with the effect size consistent with the same reported in Europeans. These results indicate an overlap of genetic effects pertaining to lipid traits across the European and Indian populations.

Replication Catastrophe

DEFF Research Database (Denmark)

Toledo, Luis; Neelsen, Kai John; Lukas, Jiri

2017-01-01

Proliferating cells rely on the so-called DNA replication checkpoint to ensure orderly completion of genome duplication, and its malfunction may lead to catastrophic genome disruption, including unscheduled firing of replication origins, stalling and collapse of replication forks, massive DNA...... breakage, and, ultimately, cell death. Despite many years of intensive research into the molecular underpinnings of the eukaryotic replication checkpoint, the mechanisms underlying the dismal consequences of its failure remain enigmatic. A recent development offers a unifying model in which the replication...... checkpoint guards against global exhaustion of rate-limiting replication regulators. Here we discuss how such a mechanism can prevent catastrophic genome disruption and suggest how to harness this knowledge to advance therapeutic strategies to eliminate cancer cells that inherently proliferate under...

DNMT1 but not its interaction with the replication machinery is required for maintenance of DNA methylation in human cells

Science.gov (United States)

Spada, Fabio; Haemmer, Andrea; Kuch, David; Rothbauer, Ulrich; Schermelleh, Lothar; Kremmer, Elisabeth; Carell, Thomas; Längst, Gernot; Leonhardt, Heinrich

2007-01-01

DNA methylation plays a central role in the epigenetic regulation of gene expression in vertebrates. Genetic and biochemical data indicated that DNA methyltransferase 1 (Dnmt1) is indispensable for the maintenance of DNA methylation patterns in mice, but targeting of the DNMT1 locus in human HCT116 tumor cells had only minor effects on genomic methylation and cell viability. In this study, we identified an alternative splicing in these cells that bypasses the disrupting selective marker and results in a catalytically active DNMT1 protein lacking the proliferating cell nuclear antigen–binding domain required for association with the replication machinery. Using a mechanism-based trapping assay, we show that this truncated DNMT1 protein displays only twofold reduced postreplicative DNA methylation maintenance activity in vivo. RNA interference–mediated knockdown of this truncated DNMT1 results in global genomic hypomethylation and cell death. These results indicate that DNMT1 is essential in mouse and human cells, but direct coupling of the replication of genetic and epigenetic information is not strictly required. PMID:17312023

Development of a duplex real-time RT-qPCR assay to monitor genome replication, gene expression and gene insert stability during in vivo replication of a prototype live attenuated canine distemper virus vector encoding SIV gag.

Science.gov (United States)

Coleman, John W; Wright, Kevin J; Wallace, Olivia L; Sharma, Palka; Arendt, Heather; Martinez, Jennifer; DeStefano, Joanne; Zamb, Timothy P; Zhang, Xinsheng; Parks, Christopher L

2015-03-01

Advancement of new vaccines based on live viral vectors requires sensitive assays to analyze in vivo replication, gene expression and genetic stability. In this study, attenuated canine distemper virus (CDV) was used as a vaccine delivery vector and duplex 2-step quantitative real-time RT-PCR (RT-qPCR) assays specific for genomic RNA (gRNA) or mRNA have been developed that concurrently quantify coding sequences for the CDV nucleocapsid protein (N) and a foreign vaccine antigen (SIV Gag). These amplicons, which had detection limits of about 10 copies per PCR reaction, were used to show that abdominal cavity lymphoid tissues were a primary site of CDV vector replication in infected ferrets, and importantly, CDV gRNA or mRNA was undetectable in brain tissue. In addition, the gRNA duplex assay was adapted for monitoring foreign gene insert genetic stability during in vivo replication by analyzing the ratio of CDV N and SIV gag genomic RNA copies over the course of vector infection. This measurement was found to be a sensitive probe for assessing the in vivo genetic stability of the foreign gene insert. Copyright © 2014 Elsevier B.V. All rights reserved.

A screen for genetic suppressor elements of hepatitis C virus identifies a supercharged protein inhibitor of viral replication.

Directory of Open Access Journals (Sweden)

Rudo L Simeon

Full Text Available Genetic suppressor elements (GSEs are biomolecules derived from a gene or genome of interest that act as transdominant inhibitors of biological functions presumably by disruption of critical biological interfaces. We exploited a cell death reporter cell line for hepatitis C virus (HCV infection, n4mBid, to develop an iterative selection/enrichment strategy for the identification of anti-HCV GSEs. Using this approach, a library of fragments of an HCV genome was screened for sequences that suppress HCV infection. A 244 amino acid gene fragment, B1, was strongly enriched after 5 rounds of selection. B1 derives from a single-base frameshift of the enhanced green fluorescent protein (eGFP which was used as a filler during fragment cloning. B1 has a very high net positive charge of 43 at neutral pH and a high charge-to-mass (kDa ratio of 1.5. We show that B1 expression specifically inhibits HCV replication. In addition, five highly positively charged B1 fragments produced from progressive truncation at the C-terminus all retain the ability to inhibit HCV, suggesting that a high positive charge, rather than a particular motif in B1, likely accounts for B1's anti-HCV activity. Another supercharged protein, +36GFP, was also found to strongly inhibit HCV replication when added to cells at the time of infection. This study reports a new methodology for HCV inhibitor screening and points to the anti-HCV potential of positively charged proteins/peptides.

SecureMA: protecting participant privacy in genetic association meta-analysis.

Science.gov (United States)

Xie, Wei; Kantarcioglu, Murat; Bush, William S; Crawford, Dana; Denny, Joshua C; Heatherly, Raymond; Malin, Bradley A

2014-12-01

Sharing genomic data is crucial to support scientific investigation such as genome-wide association studies. However, recent investigations suggest the privacy of the individual participants in these studies can be compromised, leading to serious concerns and consequences, such as overly restricted access to data. We introduce a novel cryptographic strategy to securely perform meta-analysis for genetic association studies in large consortia. Our methodology is useful for supporting joint studies among disparate data sites, where privacy or confidentiality is of concern. We validate our method using three multisite association studies. Our research shows that genetic associations can be analyzed efficiently and accurately across substudy sites, without leaking information on individual participants and site-level association summaries. Our software for secure meta-analysis of genetic association studies, SecureMA, is publicly available at http://github.com/XieConnect/SecureMA. Our customized secure computation framework is also publicly available at http://github.com/XieConnect/CircuitService. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Association and Genetic Identification of Loci for Four Fruit Traits in Tomato Using InDel Markers

Directory of Open Access Journals (Sweden)

Xiaoxi Liu

2017-07-01

Full Text Available Tomato (Solanum lycopersicum fruit weight (FW, soluble solid content (SSC, fruit shape and fruit color are crucial for yield, quality and consumer acceptability. In this study, a 192 accessions tomato association panel comprising a mixture of wild species, cherry tomato, landraces, and modern varieties collected worldwide was genotyped with 547 InDel markers evenly distributed on 12 chromosomes and scored for FW, SSC, fruit shape index (FSI, and color parameters over 2 years with three replications each year. The association panel was sorted into two subpopulations. Linkage disequilibrium ranged from 3.0 to 47.2 Mb across 12 chromosomes. A set of 102 markers significantly (p < 1.19–1.30 × 10−4 associated with SSC, FW, fruit shape, and fruit color was identified on 11 of the 12 chromosomes using a mixed linear model. The associations were compared with the known gene/QTLs for the same traits. Genetic analysis using F2 populations detected 14 and 4 markers significantly (p < 0.05 associated with SSC and FW, respectively. Some loci were commonly detected by both association and linkage analysis. Particularly, one novel locus for FW on chromosome 4 detected by association analysis was also identified in F2 populations. The results demonstrated that association mapping using limited number of InDel markers and a relatively small population could not only complement and enhance previous QTL information, but also identify novel loci for marker-assisted selection of fruit traits in tomato.

Molecular evaluation of genetic diversity and association studies in ...

Indian Academy of Sciences (India)

Molecular evaluation of genetic diversity and association studies in rice. (Oryza sativa L.) C. Vanniarajan, K. K. Vinod and Andy Pereira. J. Genet. 91, 9–19. Table 1. Chromosome-wise distribution of SSR alleles and their number (k), polymorphic information content (PIC) and allele discrimination index (Dm). Chromosome.

Hierarchical linear modeling of longitudinal pedigree data for genetic association analysis

DEFF Research Database (Denmark)

Tan, Qihua; B Hjelmborg, Jacob V; Thomassen, Mads

2014-01-01

-effect models to explicitly model the genetic relationship. These have proved to be an efficient way of dealing with sample clustering in pedigree data. Although current algorithms implemented in popular statistical packages are useful for adjusting relatedness in the mixed modeling of genetic effects...... associated with blood pressure with estimated inflation factors of 0.99, suggesting that our modeling of random effects efficiently handles the genetic relatedness in pedigrees. Application to simulated data captures important variants specified in the simulation. Our results show that the method is useful......Genetic association analysis on complex phenotypes under a longitudinal design involving pedigrees encounters the problem of correlation within pedigrees, which could affect statistical assessment of the genetic effects. Approaches have been proposed to integrate kinship correlation into the mixed...

Leveraging ethnic group incidence variation to investigate genetic susceptibility to glioma: A novel candidate SNP approach

Directory of Open Access Journals (Sweden)

Daniel Ian Jacobs

2012-10-01

Full Text Available Objectives: Using a novel candidate SNP approach, we aimed to identify a possible genetic basis for the higher glioma incidence in Whites relative to East Asians and African-Americans. Methods: We hypothesized that genetic regions containing SNPs with extreme differences in allele frequencies across ethnicities are most likely to harbor susceptibility variants. We used International HapMap Project data to identify 3,961 candidate SNPs with the largest allele frequency differences in Whites compared to East Asians and Africans and tested these SNPs for association with glioma risk in a set of White cases and controls. Top SNPs identified in the discovery dataset were tested for association with glioma in five independent replication datasets. Results: No SNP achieved statistical significance in either the discovery or replication datasets after accounting for multiple testing. However, the most strongly associated SNP, rs879471, was found to be in linkage disequilibrium with a previously identified risk SNP, rs6010620, in RTEL1. We estimate rs6010620 to account for a glioma incidence rate ratio of 1.34 for Whites relative to East Asians. Conclusions: We explored genetic susceptibility to glioma using a novel candidate SNP method which may be applicable to other diseases with appropriate epidemiologic patterns.

RNASEK Is a V-ATPase-Associated Factor Required for Endocytosis and the Replication of Rhinovirus, Influenza A Virus, and Dengue Virus

Directory of Open Access Journals (Sweden)

Jill M. Perreira

2015-08-01

Full Text Available Human rhinovirus (HRV causes upper respiratory infections and asthma exacerbations. We screened multiple orthologous RNAi reagents and identified host proteins that modulate HRV replication. Here, we show that RNASEK, a transmembrane protein, was needed for the replication of HRV, influenza A virus, and dengue virus. RNASEK localizes to the cell surface and endosomal pathway and closely associates with the vacuolar ATPase (V-ATPase proton pump. RNASEK is required for endocytosis, and its depletion produces enlarged clathrin-coated pits (CCPs at the cell surface. These enlarged CCPs contain endocytic cargo and are bound by the scissioning GTPase, DNM2. Loss of RNASEK alters the localization of multiple V-ATPase subunits and lowers the levels of the ATP6AP1 subunit. Together, our results show that RNASEK closely associates with the V-ATPase and is required for its function; its loss prevents the early events of endocytosis and the replication of multiple pathogenic viruses.

Examining a DNA Replication Requirement for Bacteriophage λ Red- and Rac Prophage RecET-Promoted Recombination in Escherichia coli

Directory of Open Access Journals (Sweden)

Lynn C. Thomason

2016-09-01

Full Text Available Recombineering, in vivo genetic engineering with bacteriophage homologous recombination systems, is a powerful technique for making genetic modifications in bacteria. Two systems widely used in Escherichia coli are the Red system from phage λ and RecET from the defective Rac prophage. We investigated the in vivo dependence of recombineering on DNA replication of the recombining substrate using plasmid targets. For λ Red recombination, when DNA replication of a circular target plasmid is prevented, recombination with single-stranded DNA oligonucleotides is greatly reduced compared to that under replicating conditions. For RecET recombination, when DNA replication of the targeted plasmid is prevented, the recombination frequency is also reduced, to a level identical to that seen for the Red system in the absence of replication. The very low level of oligonucleotide recombination observed in the absence of any phage recombination functions is the same in the presence or absence of DNA replication. In contrast, both the Red and RecET systems recombine a nonreplicating linear dimer plasmid with high efficiency to yield a circular monomer. Therefore, the DNA replication requirement is substrate dependent. Our data are consistent with recombination by both the Red and RecET systems occurring predominately by single-strand annealing rather than by strand invasion.

Self-Organization of Template-Replicating Polymers and the Spontaneous Rise of Genetic Information

Directory of Open Access Journals (Sweden)

Jarle Breivik

2001-11-01

Full Text Available Abstract: Living systems imply self-reproducing constructs capable of Darwinian evolution. How such dynamics can arise from undirected interactions between simple monomeric objects remains an open question. Here we circumvent difficulties related to the manipulation of chemical interactions, and present a system of ferromagnetic objects that self-organize into template-replicating polymers due to environmental fluctuations in temperature. Initially random sequences of monomers direct the formation of complementary sequences, and structural information is inherited from one structure to another. Selective replication of sequences occurs in dynamic interaction with the environment, and the system demonstrates the fundamental link between thermodynamics, information theory, and life science in an unprecedented manner.

Genetic association study of exfoliation syndrome identifies a protective rare variant at LOXL1 and five new susceptibility loci.

Science.gov (United States)

Aung, Tin; Ozaki, Mineo; Lee, Mei Chin; Schlötzer-Schrehardt, Ursula; Thorleifsson, Gudmar; Mizoguchi, Takanori; Igo, Robert P; Haripriya, Aravind; Williams, Susan E; Astakhov, Yury S; Orr, Andrew C; Burdon, Kathryn P; Nakano, Satoko; Mori, Kazuhiko; Abu-Amero, Khaled; Hauser, Michael; Li, Zheng; Prakadeeswari, Gopalakrishnan; Bailey, Jessica N Cooke; Cherecheanu, Alina Popa; Kang, Jae H; Nelson, Sarah; Hayashi, Ken; Manabe, Shin-Ichi; Kazama, Shigeyasu; Zarnowski, Tomasz; Inoue, Kenji; Irkec, Murat; Coca-Prados, Miguel; Sugiyama, Kazuhisa; Järvelä, Irma; Schlottmann, Patricio; Lerner, S Fabian; Lamari, Hasnaa; Nilgün, Yildirim; Bikbov, Mukharram; Park, Ki Ho; Cha, Soon Cheol; Yamashiro, Kenji; Zenteno, Juan C; Jonas, Jost B; Kumar, Rajesh S; Perera, Shamira A; Chan, Anita S Y; Kobakhidze, Nino; George, Ronnie; Vijaya, Lingam; Do, Tan; Edward, Deepak P; de Juan Marcos, Lourdes; Pakravan, Mohammad; Moghimi, Sasan; Ideta, Ryuichi; Bach-Holm, Daniella; Kappelgaard, Per; Wirostko, Barbara; Thomas, Samuel; Gaston, Daniel; Bedard, Karen; Greer, Wenda L; Yang, Zhenglin; Chen, Xueyi; Huang, Lulin; Sang, Jinghong; Jia, Hongyan; Jia, Liyun; Qiao, Chunyan; Zhang, Hui; Liu, Xuyang; Zhao, Bowen; Wang, Ya-Xing; Xu, Liang; Leruez, Stéphanie; Reynier, Pascal; Chichua, George; Tabagari, Sergo; Uebe, Steffen; Zenkel, Matthias; Berner, Daniel; Mossböck, Georg; Weisschuh, Nicole; Hoja, Ursula; Welge-Luessen, Ulrich-Christoph; Mardin, Christian; Founti, Panayiota; Chatzikyriakidou, Anthi; Pappas, Theofanis; Anastasopoulos, Eleftherios; Lambropoulos, Alexandros; Ghosh, Arkasubhra; Shetty, Rohit; Porporato, Natalia; Saravanan, Vijayan; Venkatesh, Rengaraj; Shivkumar, Chandrashekaran; Kalpana, Narendran; Sarangapani, Sripriya; Kanavi, Mozhgan R; Beni, Afsaneh Naderi; Yazdani, Shahin; Lashay, Alireza; Naderifar, Homa; Khatibi, Nassim; Fea, Antonio; Lavia, Carlo; Dallorto, Laura; Rolle, Teresa; Frezzotti, Paolo; Paoli, Daniela; Salvi, Erika; Manunta, Paolo; Mori, Yosai; Miyata, Kazunori; Higashide, Tomomi; Chihara, Etsuo; Ishiko, Satoshi; Yoshida, Akitoshi; Yanagi, Masahide; Kiuchi, Yoshiaki; Ohashi, Tsutomu; Sakurai, Toshiya; Sugimoto, Takako; Chuman, Hideki; Aihara, Makoto; Inatani, Masaru; Miyake, Masahiro; Gotoh, Norimoto; Matsuda, Fumihiko; Yoshimura, Nagahisa; Ikeda, Yoko; Ueno, Morio; Sotozono, Chie; Jeoung, Jin Wook; Sagong, Min; Park, Kyu Hyung; Ahn, Jeeyun; Cruz-Aguilar, Marisa; Ezzouhairi, Sidi M; Rafei, Abderrahman; Chong, Yaan Fun; Ng, Xiao Yu; Goh, Shuang Ru; Chen, Yueming; Yong, Victor H K; Khan, Muhammad Imran; Olawoye, Olusola O; Ashaye, Adeyinka O; Ugbede, Idakwo; Onakoya, Adeola; Kizor-Akaraiwe, Nkiru; Teekhasaenee, Chaiwat; Suwan, Yanin; Supakontanasan, Wasu; Okeke, Suhanya; Uche, Nkechi J; Asimadu, Ifeoma; Ayub, Humaira; Akhtar, Farah; Kosior-Jarecka, Ewa; Lukasik, Urszula; Lischinsky, Ignacio; Castro, Vania; Grossmann, Rodolfo Perez; Sunaric Megevand, Gordana; Roy, Sylvain; Dervan, Edward; Silke, Eoin; Rao, Aparna; Sahay, Priti; Fornero, Pablo; Cuello, Osvaldo; Sivori, Delia; Zompa, Tamara; Mills, Richard A; Souzeau, Emmanuelle; Mitchell, Paul; Wang, Jie Jin; Hewitt, Alex W; Coote, Michael; Crowston, Jonathan G; Astakhov, Sergei Y; Akopov, Eugeny L; Emelyanov, Anton; Vysochinskaya, Vera; Kazakbaeva, Gyulli; Fayzrakhmanov, Rinat; Al-Obeidan, Saleh A; Owaidhah, Ohoud; Aljasim, Leyla Ali; Chowbay, Balram; Foo, Jia Nee; Soh, Raphael Q; Sim, Kar Seng; Xie, Zhicheng; Cheong, Augustine W O; Mok, Shi Qi; Soo, Hui Meng; Chen, Xiao Yin; Peh, Su Qin; Heng, Khai Koon; Husain, Rahat; Ho, Su-Ling; Hillmer, Axel M; Cheng, Ching-Yu; Escudero-Domínguez, Francisco A; González-Sarmiento, Rogelio; Martinon-Torres, Frederico; Salas, Antonio; Pathanapitoon, Kessara; Hansapinyo, Linda; Wanichwecharugruang, Boonsong; Kitnarong, Naris; Sakuntabhai, Anavaj; Nguyn, Hip X; Nguyn, Giang T T; Nguyn, Trình V; Zenz, Werner; Binder, Alexander; Klobassa, Daniela S; Hibberd, Martin L; Davila, Sonia; Herms, Stefan; Nöthen, Markus M; Moebus, Susanne; Rautenbach, Robyn M; Ziskind, Ari; Carmichael, Trevor R; Ramsay, Michele; Álvarez, Lydia; García, Montserrat; González-Iglesias, Héctor; Rodríguez-Calvo, Pedro P; Fernández-Vega Cueto, Luis; Oguz, Çilingir; Tamcelik, Nevbahar; Atalay, Eray; Batu, Bilge; Aktas, Dilek; Kasım, Burcu; Wilson, M Roy; Coleman, Anne L; Liu, Yutao; Challa, Pratap; Herndon, Leon; Kuchtey, Rachel W; Kuchtey, John; Curtin, Karen; Chaya, Craig J; Crandall, Alan; Zangwill, Linda M; Wong, Tien Yin; Nakano, Masakazu; Kinoshita, Shigeru; den Hollander, Anneke I; Vesti, Eija; Fingert, John H; Lee, Richard K; Sit, Arthur J; Shingleton, Bradford J; Wang, Ningli; Cusi, Daniele; Qamar, Raheel; Kraft, Peter; Pericak-Vance, Margaret A; Raychaudhuri, Soumya; Heegaard, Steffen; Kivelä, Tero; Reis, André; Kruse, Friedrich E; Weinreb, Robert N; Pasquale, Louis R; Haines, Jonathan L; Thorsteinsdottir, Unnur; Jonasson, Fridbert; Allingham, R Rand; Milea, Dan; Ritch, Robert; Kubota, Toshiaki; Tashiro, Kei; Vithana, Eranga N; Micheal, Shazia; Topouzis, Fotis; Craig, Jamie E; Dubina, Michael; Sundaresan, Periasamy; Stefansson, Kari; Wiggs, Janey L; Pasutto, Francesca; Khor, Chiea Chuen

2017-07-01

Exfoliation syndrome (XFS) is the most common known risk factor for secondary glaucoma and a major cause of blindness worldwide. Variants in two genes, LOXL1 and CACNA1A, have previously been associated with XFS. To further elucidate the genetic basis of XFS, we collected a global sample of XFS cases to refine the association at LOXL1, which previously showed inconsistent results across populations, and to identify new variants associated with XFS. We identified a rare protective allele at LOXL1 (p.Phe407, odds ratio (OR) = 25, P = 2.9 × 10 -14 ) through deep resequencing of XFS cases and controls from nine countries. A genome-wide association study (GWAS) of XFS cases and controls from 24 countries followed by replication in 18 countries identified seven genome-wide significant loci (P < 5 × 10 -8 ). We identified association signals at 13q12 (POMP), 11q23.3 (TMEM136), 6p21 (AGPAT1), 3p24 (RBMS3) and 5q23 (near SEMA6A). These findings provide biological insights into the pathology of XFS and highlight a potential role for naturally occurring rare LOXL1 variants in disease biology.

Examining a DNA Replication Requirement for Bacteriophage λ Red- and Rac Prophage RecET-Promoted Recombination in Escherichia coli.

Science.gov (United States)

Thomason, Lynn C; Costantino, Nina; Court, Donald L

2016-09-13

Recombineering, in vivo genetic engineering with bacteriophage homologous recombination systems, is a powerful technique for making genetic modifications in bacteria. Two systems widely used in Escherichia coli are the Red system from phage λ and RecET from the defective Rac prophage. We investigated the in vivo dependence of recombineering on DNA replication of the recombining substrate using plasmid targets. For λ Red recombination, when DNA replication of a circular target plasmid is prevented, recombination with single-stranded DNA oligonucleotides is greatly reduced compared to that under replicating conditions. For RecET recombination, when DNA replication of the targeted plasmid is prevented, the recombination frequency is also reduced, to a level identical to that seen for the Red system in the absence of replication. The very low level of oligonucleotide recombination observed in the absence of any phage recombination functions is the same in the presence or absence of DNA replication. In contrast, both the Red and RecET systems recombine a nonreplicating linear dimer plasmid with high efficiency to yield a circular monomer. Therefore, the DNA replication requirement is substrate dependent. Our data are consistent with recombination by both the Red and RecET systems occurring predominately by single-strand annealing rather than by strand invasion. Bacteriophage homologous recombination systems are widely used for in vivo genetic engineering in bacteria. Single- or double-stranded linear DNA substrates containing short flanking homologies to chromosome targets are used to generate precise and accurate genetic modifications when introduced into bacteria expressing phage recombinases. Understanding the molecular mechanism of these recombination systems will facilitate improvements in the technology. Here, two phage-specific systems are shown to require exposure of complementary single-strand homologous targets for efficient recombination; these single

What Ideas Do Students Associate with "Biotechnology" and "Genetic Engineering"?

Science.gov (United States)

Hill, Ruaraidh; Stanisstreet, Martin; Boyes, Edward

2000-01-01

Explores the ideas that students aged 16-19 associate with the terms 'biotechnology' and 'genetic engineering'. Indicates that some students see biotechnology as risky whereas genetic engineering was described as ethically wrong. (Author/ASK)

Seasonality shows evidence for polygenic architecture and genetic correlation with schizophrenia and bipolar disorder – a meta-analysis of genetic studies

Science.gov (United States)

Byrne, Enda M; Raheja, Uttam; Stephens, Sarah H.; Heath, Andrew C; Madden, Pamela AF; Vaswani, Dipika; Nijjar, Gagan V.; Ryan, Kathleen A.; Youssufi, Hassaan; Gehrman, Philip R; Shuldiner, Alan R; Martin, Nicholas G; Montgomery, Grant W; Wray, Naomi R; Nelson, Elliot C; Mitchell, Braxton D; Postolache, Teodor T

2015-01-01

Objective To test common genetic variants for association with seasonality (seasonal changes in mood and behavior) and to investigate whether there are shared genetic risk factors between psychiatric disorders and seasonality. Methods A meta-analysis of genome-wide association studies (GWAS) conducted in Australian and Amish populations in whom the Seasonal Pattern Assessment Questionnaire (SPAQ) had been administered. The total sample size was 4,156 individuals. Genetic risk scores based on results from prior large GWAS studies of bipolar disorder (BD), major depressive disorder (MDD), and schizophrenia (SCZ) were calculated to test for overlap in risk between psychiatric disorders and seasonality. Results The most significant association was with rs11825064 (p = 1.7 × 10−6, β = 0.64, S.E = 0.13), an intergenic SNP found on chromosome 11. The evidence for overlap in risk factors was strongest for SCZ and seasonality, with the SCZ genetic profile scores explaining 3% of the variance in log-transformed GSS. BD genetic profile scores were also significantly associated with seasonality, although at much weaker levels, and no evidence for overlap in risk was detected between MDD and seasonality. Conclusions Common SNPs of very large effect likely do not exist for seasonality in the populations examined. As expected, there was overlapping genetic risk factors for BD (but not MDD) with seasonality. Unexpectedly, the risk for SCZ and seasonality had the largest overlap, an unprecedented finding that requires replication in other populations, and has potential clinical implications considering overlapping cognitive deficits in seasonal affective disorders and SCZ PMID:25562672

A replicated climate change field experiment reveals rapid evolutionary response in an ecologically important soil invertebrate

DEFF Research Database (Denmark)

Bataillon, Thomas; Galtier, Nicolas; Bernard, Aurelien

2016-01-01

to climate change in a common annelid worm using a controlled replicated experiment where climatic conditions were manipulated in a natural setting. Analyzing the transcribed genome of 15 local populations, we found that about 12% of the genetic polymorphisms exhibit differences in allele frequencies......Whether species can respond evolutionarily to current climate change is crucial for the persistence of many species. Yet, very few studies have examined genetic responses to climate change in manipulated experiments carried out innatural field conditions. We examined the evolutionary response...... associated to changes in soil temperature and soil moisture. This shows an evolutionaryresponse to realistic climate change happening over short-time scale, and calls for incorporating evolution into modelspredicting future response of species to climate change. It also shows that designed climate change...

Insight into the Genetic Components of Community Genetics: QTL Mapping of Insect Association in a Fast-Growing Forest Tree

NARCIS (Netherlands)

DeWoody, J.; Viger, M.; Lakatos, F.; Tuba, K.; Taylor, G.; Smulders, M.J.M.

2013-01-01

Identifying genetic sequences underlying insect associations on forest trees will improve the understanding of community genetics on a broad scale. We tested for genomic regions associated with insects in hybrid poplar using quantitative trait loci (QTL) analyses conducted on data from a common

Database Replication Prototype

OpenAIRE

Vandewall, R.

2000-01-01

This report describes the design of a Replication Framework that facilitates the implementation and com-parison of database replication techniques. Furthermore, it discusses the implementation of a Database Replication Prototype and compares the performance measurements of two replication techniques based on the Atomic Broadcast communication primitive: pessimistic active replication and optimistic active replication. The main contributions of this report can be split into four parts....

Age at onset in Huntington's disease: replication study on the association of HAP1.

Science.gov (United States)

Karadima, Georgia; Dimovasili, Christina; Koutsis, Georgios; Vassilopoulos, Demetris; Panas, Marios

2012-11-01

In recent years two association studies investigating the HAP1 T441M (rs4523977) polymorphism as a potential modifying factor of the age at onset (AAO) of Huntington's disease (HD), have been reported. Initially evidence for association was found between the M441 risk allele and the AAO. Subsequently, a second study, although failing to replicate these findings, found evidence for association between the same risk allele and AAO of motor symptoms (mAAO). In the present study, the role of the HAP1 T441M polymorphism as a modifier of the AAO in HD was investigated in a cohort of 298 Greek HD patients. In this cohort the CAG repeat number accounted for 55% of the variance in AAO. No association was found between the HAP1 T441M polymorphism and the AAO of HD. © 2012 Elsevier Ltd. All rights reserved.

Identification of Poxvirus Genome Uncoating and DNA Replication Factors with Mutually Redundant Roles.

Science.gov (United States)

Liu, Baoming; Panda, Debasis; Mendez-Rios, Jorge D; Ganesan, Sundar; Wyatt, Linda S; Moss, Bernard

2018-04-01

Genome uncoating is essential for replication of most viruses. For poxviruses, the process is divided into two stages: removal of the envelope, allowing early gene expression, and breaching of the core wall, allowing DNA release, replication, and late gene expression. Subsequent studies showed that the host proteasome and the viral D5 protein, which has an essential role in DNA replication, are required for vaccinia virus (VACV) genome uncoating. In a search for additional VACV uncoating proteins, we noted a report that described a defect in DNA replication and late expression when the gene encoding a 68-kDa ankyrin repeat/F-box protein (68k-ank), associated with the cellular SCF (Skp1, cullin1, F-box-containing complex) ubiquitin ligase complex, was deleted from the attenuated modified vaccinia virus Ankara (MVA). Here we showed that the 68k-ank deletion mutant exhibited diminished genome uncoating, formation of DNA prereplication sites, and degradation of viral cores as well as an additional, independent defect in DNA synthesis. Deletion of the 68k-ank homolog of VACV strain WR, however, was without effect, suggesting the existence of compensating genes. By inserting VACV genes into an MVA 68k-ank deletion mutant, we discovered that M2, a member of the poxvirus immune evasion (PIE) domain superfamily and a regulator of NF-κB, and C5, a member of the BTB/Kelch superfamily associated with cullin-3-based ligase complexes, independently rescued the 68k-ank deletion phenotype. Thus, poxvirus uncoating and DNA replication are intertwined processes involving at least three viral proteins with mutually redundant functions in addition to D5. IMPORTANCE Poxviruses comprise a family of large DNA viruses that infect vertebrates and invertebrates and cause diseases of medical and zoological importance. Poxviruses, unlike most other DNA viruses, replicate in the cytoplasm, and their large genomes usually encode 200 or more proteins with diverse functions. About 90 genes may

Histone hypoacetylation is required to maintain late replication timing of constitutive heterochromatin.

Science.gov (United States)

Casas-Delucchi, Corella S; van Bemmel, Joke G; Haase, Sebastian; Herce, Henry D; Nowak, Danny; Meilinger, Daniela; Stear, Jeffrey H; Leonhardt, Heinrich; Cardoso, M Cristina

2012-01-01

The replication of the genome is a spatio-temporally highly organized process. Yet, its flexibility throughout development suggests that this process is not genetically regulated. However, the mechanisms and chromatin modifications controlling replication timing are still unclear. We made use of the prominent structure and defined heterochromatic landscape of pericentric regions as an example of late replicating constitutive heterochromatin. We manipulated the major chromatin markers of these regions, namely histone acetylation, DNA and histone methylation, as well as chromatin condensation and determined the effects of these altered chromatin states on replication timing. Here, we show that manipulation of DNA and histone methylation as well as acetylation levels caused large-scale heterochromatin decondensation. Histone demethylation and the concomitant decondensation, however, did not affect replication timing. In contrast, immuno-FISH and time-lapse analyses showed that lowering DNA methylation, as well as increasing histone acetylation, advanced the onset of heterochromatin replication. While dnmt1(-)(/)(-) cells showed increased histone acetylation at chromocenters, histone hyperacetylation did not induce DNA demethylation. Hence, we propose that histone hypoacetylation is required to maintain normal heterochromatin duplication dynamics. We speculate that a high histone acetylation level might increase the firing efficiency of origins and, concomitantly, advances the replication timing of distinct genomic regions.

GWA study data mining and independent replication identify cardiomyopathy-associated 5 (CMYA5) as a risk gene for schizophrenia

NARCIS (Netherlands)

Chen, X.; Lee, G.; Maher, B. S.; Fanous, A. H.; Chen, J.; Zhao, Z.; Guo, A.; van den Oord, E.; Sullivan, P. F.; Shi, J.; Levinson, D. F.; Gejman, P. V.; Sanders, A.; Duan, J.; Owen, M. J.; Craddock, N. J.; O'Donovan, M. C.; Blackman, J.; Lewis, D.; Kirov, G. K.; Qin, W.; Schwab, S.; Wildenauer, D.; Chowdari, K.; Nimgaonkar, V.; Straub, R. E.; Weinberger, D. R.; O'Neill, F. A.; Walsh, D.; Bronstein, M.; Darvasi, A.; Lencz, T.; Malhotra, A. K.; Rujescu, D.; Giegling, I.; Werge, T.; Hansen, T.; Ingason, A.; Nöethen, M. M.; Rietschel, M.; Cichon, S.; Djurovic, S.; Andreassen, O. A.; Cantor, R. M.; Ophoff, R.; Corvin, A.; Morris, D. W.; Gill, M.; Pato, C. N.; Pato, M. T.; Macedo, A.; Gurling, H. M. D.; McQuillin, A.; Pimm, J.; Hultman, C.; Lichtenstein, P.; Sklar, P.; Purcell, S. M.; Scolnick, E.; St Clair, D.; Blackwood, D. H. R.; Kendler, K. S.; Kahn, René S.; Linszen, Don H.; van Os, Jim; Wiersma, Durk; Bruggeman, Richard; Cahn, Wiepke; de Haan, Lieuwe; Krabbendam, Lydia; Myin-Germeys, Inez; O'Donovan, Michael C.; Kirov, George K.; Craddock, Nick J.; Holmans, Peter A.; Williams, Nigel M.; Georgieva, Lyudmila; Nikolov, Ivan; Norton, N.; Williams, H.; Toncheva, Draga; Milanova, Vihra; Owen, Michael J.; Hultman, Christina M.; Lichtenstein, Paul; Thelander, Emma F.; Sullivan, Patrick; Morris, Derek W.; O'Dushlaine, Colm T.; Kenny, Elaine; Quinn, Emma M.; Gill, Michael; Corvin, Aiden; McQuillin, Andrew; Choudhury, Khalid; Datta, Susmita; Pimm, Jonathan; Thirumalai, Srinivasa; Puri, Vinay; Krasucki, Robert; Lawrence, Jacob; Quested, Digby; Bass, Nicholas; Gurling, Hugh; Crombie, Caroline; Fraser, Gillian; Kuan, Soh Leh; Walker, Nicholas; St Clair, David; Blackwood, Douglas H. R.; Muir, Walter J.; McGhee, Kevin A.; Pickard, Ben; Malloy, Pat; Maclean, Alan W.; van Beck, Margaret; Wray, Naomi R.; Macgregor, Stuart; Visscher, Peter M.; Pato, Michele T.; Medeiros, Helena; Middleton, Frank; Carvalho, Celia; Morley, Christopher; Fanous, Ayman; Conti, David; Knowles, James A.; Ferreira, Carlos Paz; Macedo, Antonio; Azevedo, M. Helena; Pato, Carlos N.; Stone, Jennifer L.; Ruderfer, Douglas M.; Kirby, Andrew N.; Ferreira, Manuel A. R.; Daly, Mark J.; Purcell, Shaun M.; Sklar, Pamela; Chambert, Kimberly; Kuruvilla, Finny; Gabriel, Stacey B.; Ardlie, Kristin; Moran, Jennifer L.; Scolnick, Edward M.

2011-01-01

We conducted data-mining analyses using the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) and molecular genetics of schizophrenia genome-wide association study supported by the genetic association information network (MGS-GAIN) schizophrenia data sets and performed

Novel genetic loci associated with hippocampal volume

OpenAIRE

Hibar, Derrek P.; Adams, Hieab H. H.; Jahanshad, Neda; Chauhan, Ganesh; Stein, Jason L.; Hofer, Edith; Renteria, Miguel E.; Bis, Joshua C.; Arias-Vasquez, Alejandro; Ikram, M. Kamran; Desrivieres, Sylvane; Vernooij, Meike W.; Abramovic, Lucija; Alhusaini, Saud; Amin, Najaf

2017-01-01

International audience; The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal ...

Infidelity of SARS-CoV Nsp14-exonuclease mutant virus replication is revealed by complete genome sequencing.

Directory of Open Access Journals (Sweden)

Lance D Eckerle

2010-05-01

Full Text Available Most RNA viruses lack the mechanisms to recognize and correct mutations that arise during genome replication, resulting in quasispecies diversity that is required for pathogenesis and adaptation. However, it is not known how viruses encoding large viral RNA genomes such as the Coronaviridae (26 to 32 kb balance the requirements for genome stability and quasispecies diversity. Further, the limits of replication infidelity during replication of large RNA genomes and how decreased fidelity impacts virus fitness over time are not known. Our previous work demonstrated that genetic inactivation of the coronavirus exoribonuclease (ExoN in nonstructural protein 14 (nsp14 of murine hepatitis virus results in a 15-fold decrease in replication fidelity. However, it is not known whether nsp14-ExoN is required for replication fidelity of all coronaviruses, nor the impact of decreased fidelity on genome diversity and fitness during replication and passage. We report here the engineering and recovery of nsp14-ExoN mutant viruses of severe acute respiratory syndrome coronavirus (SARS-CoV that have stable growth defects and demonstrate a 21-fold increase in mutation frequency during replication in culture. Analysis of complete genome sequences from SARS-ExoN mutant viral clones revealed unique mutation sets in every genome examined from the same round of replication and a total of 100 unique mutations across the genome. Using novel bioinformatic tools and deep sequencing across the full-length genome following 10 population passages in vitro, we demonstrate retention of ExoN mutations and continued increased diversity and mutational load compared to wild-type SARS-CoV. The results define a novel genetic and bioinformatics model for introduction and identification of multi-allelic mutations in replication competent viruses that will be powerful tools for testing the effects of decreased fidelity and increased quasispecies diversity on viral replication

Genetic factors affecting dental caries risk.

Science.gov (United States)

Opal, S; Garg, S; Jain, J; Walia, I

2015-03-01

This article reviews the literature on genetic aspects of dental caries and provides a framework for the rapidly changing disease model of caries. The scope is genetic aspects of various dental factors affecting dental caries. The PubMed database was searched for articles with keywords 'caries', 'genetics', 'taste', 'diet' and 'twins'. This was followed by extensive handsearching using reference lists from relevant articles. The post-genomic era will present many opportunities for improvement in oral health care but will also present a multitude of challenges. We can conclude from the literature that genes have a role to play in dental caries; however, both environmental and genetic factors have been implicated in the aetiology of caries. Additional studies will have to be conducted to replicate the findings in a different population. Identification of genetic risk factors will help screen and identify susceptible patients to better understand the contribution of genes in caries aetiopathogenesis. Information derived from these diverse studies will provide new tools to target individuals and/or populations for a more efficient and effective implementation of newer preventive measures and diagnostic and novel therapeutic approaches in the management of this disease. © 2015 Australian Dental Association.

Genetic and Environmental Associations Between Procrastination and Internalizing/Externalizing Psychopathology.

Science.gov (United States)

Gustavson, Daniel E; du Pont, Alta; Hatoum, Alexander S; Hyun Rhee, Soo; Kremen, William S; Hewitt, John K; Friedman, Naomi P

2017-09-01

Recent work on procrastination has begun to unravel the genetic and environmental correlates of this problematic behavior. However, little is known about how strongly procrastination is associated with internalizing and externalizing psychopathology, and the extent to which shared genetic/environmental factors or relevant personality constructs (e.g., fear of failure, impulsivity, and neuroticism) can inform the structure of these associations. The current study examined data from 764 young adult twins who completed questionnaires assessing procrastination and personality and structured interviews regarding psychopathology symptoms. Results indicated that procrastination was positively correlated with both internalizing and externalizing latent variables, and that these correlations were driven by shared genetic influences. Moreover, the association between procrastination and internalizing was accounted for by fear of failure and neuroticism, whereas the association between procrastination and externalizing was primarily explained by impulsivity. The role of procrastination in psychopathology is discussed using a framework that highlights common and broadband-specific variance.

HLA-A*31:01 and HLA-B*15:02 as genetic markers for carbamazepine hypersensitivity in children

Science.gov (United States)

Amstutz, Ursula; Ross, Colin J.D.; Castro-Pastrana, Lucila I.; Rieder, Michael J.; Shear, Neil H.; Hayden, Michael R.; Carleton, Bruce C.

2013-01-01

The occurrence of hypersensitivity reactions including rare but life-threatening Stevens-Johnson syndrome (SJS) and drug-induced hypersensitivity syndrome (HSS) limits the use of the anticonvulsant carbamazepine (CBZ). HLA-B*15:02 and HLA-A*31:01 have been identified as predictive genetic markers for CBZ hypersensitivity in Asian and European patients. To replicate these genetic associations in pediatric patients from North America with a diverse ethnic background, we investigated HLA-A*31:01 and HLA-B*15:02 in 42 children with CBZ hypersensitivity, and 91 CBZ-tolerant children from across Canada. HLA-A*31:01 was significantly associated with CBZ-HSS (odds ratio (OR): 26.4, p=0.0025) and maculopapular exanthems (OR: 8.6, p=0.0037), but not with CBZ-SJS. Conversely, HLA-B*15:02 was associated with CBZ-SJS (OR: 38.6, p=0.002), but not HSS and maculopapular exanthems. This study is the first to demonstrate the association of HLA-A*31:01 with CBZ hypersensitivity in children, providing important replication of this association and highlighting the importance of HLA-A*31:01 as a predictive biomarker across various ancestries. PMID:23588310

Systemic Age-Associated DNA Hypermethylation of ELOVL2 Gene: In Vivo and In Vitro Evidences of a Cell Replication Process.

Science.gov (United States)

Bacalini, Maria Giulia; Deelen, Joris; Pirazzini, Chiara; De Cecco, Marco; Giuliani, Cristina; Lanzarini, Catia; Ravaioli, Francesco; Marasco, Elena; van Heemst, Diana; Suchiman, H Eka D; Slieker, Roderick; Giampieri, Enrico; Recchioni, Rina; Mercheselli, Fiorella; Salvioli, Stefano; Vitale, Giovanni; Olivieri, Fabiola; Spijkerman, Annemieke M W; Dollé, Martijn E T; Sedivy, John M; Castellani, Gastone; Franceschi, Claudio; Slagboom, Pieternella E; Garagnani, Paolo

2017-08-01

Epigenetic remodeling is one of the major features of the aging process. We recently demonstrated that DNA methylation of ELOVL2 and FHL2 CpG islands is highly correlated with age in whole blood. Here we investigated several aspects of age-associated hypermethylation of ELOVL2 and FHL2. We showed that ELOVL2 methylation is significantly different in primary dermal fibroblast cultures from donors of different ages. Using epigenomic data from public resources, we demonstrated that most of the tissues show ELOVL2 and FHL2 hypermethylation with age. Interestingly, ELOVL2 hypermethylation was not found in tissues with very low replication rate. We demonstrated that ELOVL2 hypermethylation is associated with in vitro cell replication rather than with senescence. We confirmed intra-individual hypermethylation of ELOVL2 and FHL2 in longitudinally assessed participants from the Doetinchem Cohort Study. Finally we showed that, although the methylation of the two loci is not associated with longevity/mortality in the Leiden Longevity Study, ELOVL2 methylation is associated with cytomegalovirus status in nonagenarians, which could be informative of a higher number of replication events in a fraction of whole-blood cells. Collectively, these results indicate that ELOVL2 methylation is a marker of cell divisions occurring during human aging. © The Author 2016. 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.

Distinct functions of human RecQ helicases during DNA replication.

Science.gov (United States)

Urban, Vaclav; Dobrovolna, Jana; Janscak, Pavel

2017-06-01

DNA replication is the most vulnerable process of DNA metabolism in proliferating cells and therefore it is tightly controlled and coordinated with processes that maintain genomic stability. Human RecQ helicases are among the most important factors involved in the maintenance of replication fork integrity, especially under conditions of replication stress. RecQ helicases promote recovery of replication forks being stalled due to different replication roadblocks of either exogenous or endogenous source. They prevent generation of aberrant replication fork structures and replication fork collapse, and are involved in proper checkpoint signaling. The essential role of human RecQ helicases in the genome maintenance during DNA replication is underlined by association of defects in their function with cancer predisposition. Copyright © 2016 Elsevier B.V. All rights reserved.

Understanding Salesforce Behavior using Genetic Association Studies

NARCIS (Netherlands)

W.E. van den Berg (Wouter)

2014-01-01

markdownabstract__Abstract__ Using genetic association studies, this thesis aims to investigate the drivers of successful customer-salesperson interactions in a context where knowledge development has become crucial to the value creation process. Central to this thesis is the developing role of

An analysis of food irradiation : genetic effects

International Nuclear Information System (INIS)

MacPhee, D.; Hall, W.

1988-01-01

A series of studies undertaken at the National Institute of Nutrition (NIN) in India in the 1970s reported the occurrence of polyploidy in bone-marrow or peripheral lymphocytes in a number of species, including children, fed on freshly irradiated wheat. Opponents of food irradiation use these studies as evidence that genetic damage is caused by the consumption of irradiated food. This review of those NIN studies and of the attempts to replicate them and of two other relevant studies concludes that the claim that consumption of irradiated food causes genetic damage has not been substantiated. Other researchers have been unable to replicate the NIN studies. Polyploidy appears to be a poor indicator of genetic damage and the NIN results are biologically implausible

A genetic association study between growth differentiation factor 5 (GDF 5 polymorphism and knee osteoarthritis in Thai population

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Sura Thanyachai

2011-09-01

Full Text Available Abstract Objective Osteoarthritis (OA is a multi-factorial disease and genetic factor is one of the important etiologic risk factors. Various genetic polymorphisms have been elucidated that they might be associated with OA. Recently, several studies have shown an association between Growth Differentiation Factor 5(GDF5 polymorphism and knee OA. However, the role of genetic predisposing factor in each ethnic group cannot be replicated to all, with conflicting data in the literatures. Therefore, the aim of this study was to investigate the association between GDF5 polymorphism and knee OA in Thai population. Materials and Methods One hundred and ninety three patients aged 54-88 years who attended Ramathibodi Hospital were enrolled. Ninety cases with knee OA according to American College of Rheumatology criteria and one hundred and three cases in control group gave informed consent. Blood sample (5 ml were collected for identification of GDF5 (rs143383 single nucleotide polymorphism by PCR/RFLP according to a standard protocol. This study protocol was approved by the Ethics Committee on human experimentation of Ramathibodi Hospital Faculty of Medicine, Mahidol University. Odds ratios (OR and 95% confidence intervals were calculated for the risk of knee OA by genotype (TT, TC and CC and allele (T/C analyses. Results The baseline characteristics between two groups including job, smoking and activity were not different, except age and BMI. The entire cases and controls were in Hardy-Weinberg equilibrium (p > 0.05. The OA knee group (n = 90 had genotypic figure which has shown by TT 42.2% (n = 38, TC 45.6% (n = 41 and CC 12% (n = 11, whereas the control group (n = 103 revealed TT 32% (n = 33, TC 45.6% (n = 47, and CC 22.3% (n = 23, respectively. Genotypic TT increased risk of knee OA as compared to CC [OR = 2.41 (P = 0.04, 95%CI = 1.02-5.67]. In the allele analysis, the T allele was found to be significantly associated with knee OA [OR = 1.53 (P = 0

MetaGenyo: a web tool for meta-analysis of genetic association studies.

Science.gov (United States)

Martorell-Marugan, Jordi; Toro-Dominguez, Daniel; Alarcon-Riquelme, Marta E; Carmona-Saez, Pedro

2017-12-16

Genetic association studies (GAS) aims to evaluate the association between genetic variants and phenotypes. In the last few years, the number of this type of study has increased exponentially, but the results are not always reproducible due to experimental designs, low sample sizes and other methodological errors. In this field, meta-analysis techniques are becoming very popular tools to combine results across studies to increase statistical power and to resolve discrepancies in genetic association studies. A meta-analysis summarizes research findings, increases statistical power and enables the identification of genuine associations between genotypes and phenotypes. Meta-analysis techniques are increasingly used in GAS, but it is also increasing the amount of published meta-analysis containing different errors. Although there are several software packages that implement meta-analysis, none of them are specifically designed for genetic association studies and in most cases their use requires advanced programming or scripting expertise. We have developed MetaGenyo, a web tool for meta-analysis in GAS. MetaGenyo implements a complete and comprehensive workflow that can be executed in an easy-to-use environment without programming knowledge. MetaGenyo has been developed to guide users through the main steps of a GAS meta-analysis, covering Hardy-Weinberg test, statistical association for different genetic models, analysis of heterogeneity, testing for publication bias, subgroup analysis and robustness testing of the results. MetaGenyo is a useful tool to conduct comprehensive genetic association meta-analysis. The application is freely available at http://bioinfo.genyo.es/metagenyo/ .

Aberrant allele-specific replication, independent of parental origin, in blood cells of cancer patients

International Nuclear Information System (INIS)

Dotan, Zohar A; Dotan, Aviva; Ramon, Jacob; Avivi, Lydia

2008-01-01

Allelic counterparts of biallelically expressed genes display an epigenetic symmetry normally manifested by synchronous replication, different from genes subjected to monoallelic expression, which normally are characterized by an asynchronous mode of replication (well exemplified by the SNRPN imprinted locus). Malignancy was documented to be associated with gross modifications in the inherent replication-timing coordination between allelic counterparts of imprinted genes as well as of biallelically expressed loci. The cancer-related allelic replication timing aberrations are non-disease specific and appear in peripheral blood cells of cancer patients, including those with solid tumors. As such they offer potential blood markers for non-invasive cancer test. The present study was aimed to gain some insight into the mechanism leading to the replication timing alterations of genes in blood lymphocytes of cancer patients. Peripheral blood samples derived from patients with prostate cancer were chosen to represent the cancerous status, and samples taken from patients with no cancer but with benign prostate hyperplasia were used to portray the normal status. Fluorescence In Situ Hybridization (FISH) replication assay, applied to phytohemagglutinin (PHA)-stimulated blood lymphocytes, was used to evaluate the temporal order (either synchronous or asynchronous) of genes in the patients' cells. We demonstrated that: (i) the aberrant epigenetic profile, as delineated by the cancer status, is a reversible modification, evidenced by our ability to restore the normal patterns of replication in three unrelated loci (CEN15, SNRPN and RB1) by introducing an archetypical demethylating agent, 5-azacytidine; (ii) following the rehabilitating effect of demethylation, an imprinted gene (SNRPN) retains its original parental imprint; and (iii) the choice of an allele between early or late replication in the aberrant asynchronous replication, delineated by the cancer status, is not

Genetic diversity of disease-associated loci in Turkish population.

Science.gov (United States)

Karaca, Sefayet; Cesuroglu, Tomris; Karaca, Mehmet; Erge, Sema; Polimanti, Renato

2015-04-01

Many consortia and international projects have investigated the human genetic variation of a large number of ethno-geographic groups. However, populations with peculiar genetic features, such as the Turkish population, are still absent in publically available datasets. To explore the genetic predisposition to health-related traits of the Turkish population, we analyzed 34 genes associated with different health-related traits (for example, lipid metabolism, cardio-vascular diseases, hormone metabolism, cellular detoxification, aging and energy metabolism). We observed relevant differences between the Turkish population and populations with non-European ancestries (that is, Africa and East Asia) in some of the investigated genes (that is, AGT, APOE, CYP1B1, GNB3, IL10, IL6, LIPC and PON1). As most complex traits are highly polygenic, we developed polygenic scores associated with different health-related traits to explore the genetic diversity of the Turkish population with respect to other human groups. This approach showed significant differences between the Turkish population and populations with non-European ancestries, as well as between Turkish and Northern European individuals. This last finding is in agreement with the genetic structure of European and Middle East populations, and may also agree with epidemiological evidences about the health disparities of Turkish communities in Northern European countries.

Multiple Genetic Associations with Irish Wolfhound Dilated Cardiomyopathy.

Science.gov (United States)

Simpson, Siobhan; Dunning, Mark D; Brownlie, Serena; Patel, Janika; Godden, Megan; Cobb, Malcolm; Mongan, Nigel P; Rutland, Catrin S

2016-01-01

Cardiac disease is a leading cause of morbidity and mortality in dogs and humans, with dilated cardiomyopathy being a large contributor to this. The Irish Wolfhound (IWH) is one of the most commonly affected breeds and one of the few breeds with genetic loci associated with the disease. Mutations in more than 50 genes are associated with human dilated cardiomyopathy (DCM), yet very few are also associated with canine DCM. Furthermore, none of the identified canine loci explain many cases of the disease and previous work has indicated that genotypes at multiple loci may act together to influence disease development. In this study, loci previously associated with DCM in IWH were tested for associations in a new cohort both individually and in combination. We have identified loci significantly associated with the disease individually, but no genotypes individually or in pairs conferred a significantly greater risk of developing DCM than the population risk. However combining three loci together did result in the identification of a genotype which conferred a greater risk of disease than the overall population risk. This study suggests multiple rather than individual genetic factors, cooperating to influence DCM risk in IWH.

Multiple Genetic Associations with Irish Wolfhound Dilated Cardiomyopathy

Directory of Open Access Journals (Sweden)

Siobhan Simpson

2016-01-01

Full Text Available Cardiac disease is a leading cause of morbidity and mortality in dogs and humans, with dilated cardiomyopathy being a large contributor to this. The Irish Wolfhound (IWH is one of the most commonly affected breeds and one of the few breeds with genetic loci associated with the disease. Mutations in more than 50 genes are associated with human dilated cardiomyopathy (DCM, yet very few are also associated with canine DCM. Furthermore, none of the identified canine loci explain many cases of the disease and previous work has indicated that genotypes at multiple loci may act together to influence disease development. In this study, loci previously associated with DCM in IWH were tested for associations in a new cohort both individually and in combination. We have identified loci significantly associated with the disease individually, but no genotypes individually or in pairs conferred a significantly greater risk of developing DCM than the population risk. However combining three loci together did result in the identification of a genotype which conferred a greater risk of disease than the overall population risk. This study suggests multiple rather than individual genetic factors, cooperating to influence DCM risk in IWH.

Disease-Concordant Twins Empower Genetic Association Studies

DEFF Research Database (Denmark)

Tan, Qihua; Li, Weilong; Vandin, Fabio

2017-01-01

and ordinary healthy samples as controls. We examined the power gain of the twin-based design for various scenarios (i.e., cases from monozygotic and dizygotic twin pairs concordant for a disease) and compared the power with the ordinary case-control design with cases collected from the unrelated patient...... concordant for a disease, should confer increased power in genetic association analysis because of their genetic relatedness. We conducted a computer simulation study to explore the power advantage of the disease-concordant twin design, which uses singletons from disease-concordant twin pairs as cases...... population. Simulation was done by assigning various allele frequencies and allelic relative risks for different mode of genetic inheritance. In general, for achieving a power estimate of 80%, the sample sizes needed for dizygotic and monozygotic twin cases were one half and one fourth of the sample size...

The Replication Recipe: What makes for a convincing replication?

NARCIS (Netherlands)

Brandt, M.J.; IJzerman, H.; Dijksterhuis, A.J.; Farach, F.J.; Geller, J.; Giner-Sorolla, R.; Grange, J.A.; Perugini, M.; Spies, J.R.; Veer, A. van 't

2014-01-01

Psychological scientists have recently started to reconsider the importance of close replications in building a cumulative knowledge base; however, there is no consensus about what constitutes a convincing close replication study. To facilitate convincing close replication attempts we have developed

The replication recipe : What makes for a convincing replication?

NARCIS (Netherlands)

Brandt, M.J.; IJzerman, H.; Dijksterhuis, Ap; Farach, Frank J.; Geller, Jason; Giner-Sorolla, Roger; Grange, James A.; Perugini, Marco; Spies, Jeffrey R.; van 't Veer, Anna

Psychological scientists have recently started to reconsider the importance of close replications in building a cumulative knowledge base; however, there is no consensus about what constitutes a convincing close replication study. To facilitate convincing close replication attempts we have developed

Beyond the usual suspects: a multidimensional genetic exploration of infant attachment disorganization and security.

Science.gov (United States)

Pappa, Irene; Szekely, Eszter; Mileva-Seitz, Viara R; Luijk, Maartje P C M; Bakermans-Kranenburg, Marian J; van IJzendoorn, Marinus H; Tiemeier, Henning

2015-01-01

Although the environmental influences on infant attachment disorganization and security are well-studied, little is known about their heritability. Candidate gene studies have shown small, often non-replicable effects. In this study, we gathered the largest sample (N = 657) of ethnically homogenous, 14-month-old children with both observed attachment and genome-wide data. First, we used a Genome-Wide Association Study (GWAS) approach to identify single nucleotide polymorphisms (SNPs) associated with attachment disorganization and security. Second, we annotated them into genes (Versatile Gene-based Association Study) and functional pathways. Our analyses provide evidence of novel genes (HDAC1, ZNF675, BSCD1) and pathways (synaptic transmission, cation transport) associated with attachment disorganization. Similar analyses identified a novel gene (BECN1) but no distinct pathways associated with attachment security. The results of this first extensive, exploratory study on the molecular-genetic basis of infant attachment await replication in large, independent samples.

Replication studies in longevity

DEFF Research Database (Denmark)

Varcasia, O; Garasto, S; Rizza, T

2001-01-01

In Danes we replicated the 3'APOB-VNTR gene/longevity association study previously carried out in Italians, by which the Small alleles (less than 35 repeats) had been identified as frailty alleles for longevity. In Danes, neither genotype nor allele frequencies differed between centenarians and 20...

Are genetic risk factors for psychosis also associated with dimension-specific psychotic experiences in adolescence?

Directory of Open Access Journals (Sweden)

Dominika Sieradzka

Full Text Available Psychosis has been hypothesised to be a continuously distributed quantitative phenotype and disorders such as schizophrenia and bipolar disorder represent its extreme manifestations. Evidence suggests that common genetic variants play an important role in liability to both schizophrenia and bipolar disorder. Here we tested the hypothesis that these common variants would also influence psychotic experiences measured dimensionally in adolescents in the general population. Our aim was to test whether schizophrenia and bipolar disorder polygenic risk scores (PRS, as well as specific single nucleotide polymorphisms (SNPs previously identified as risk variants for schizophrenia, were associated with adolescent dimension-specific psychotic experiences. Self-reported Paranoia, Hallucinations, Cognitive Disorganisation, Grandiosity, Anhedonia, and Parent-rated Negative Symptoms, as measured by the Specific Psychotic Experiences Questionnaire (SPEQ, were assessed in a community sample of 2,152 16-year-olds. Polygenic risk scores were calculated using estimates of the log of odds ratios from the Psychiatric Genomics Consortium GWAS stage-1 mega-analysis of schizophrenia and bipolar disorder. The polygenic risk analyses yielded no significant associations between schizophrenia and bipolar disorder PRS and the SPEQ measures. The analyses on the 28 individual SNPs previously associated with schizophrenia found that two SNPs in TCF4 returned a significant association with the SPEQ Paranoia dimension, rs17512836 (p-value = 2.57×10⁻⁴ and rs9960767 (p-value = 6.23×10⁻⁴. Replication in an independent sample of 16-year-olds (N = 3,427 assessed using the Psychotic-Like Symptoms Questionnaire (PLIKS-Q, a composite measure of multiple positive psychotic experiences, failed to yield significant results. Future research with PRS derived from larger samples, as well as larger adolescent validation samples, would improve the predictive power to test

Genetic variants are major determinants of CSF antibody levels in multiple sclerosis

DEFF Research Database (Denmark)

Goris, An; Pauwels, Ine; Gustavsen, Marte W

2015-01-01

Immunological hallmarks of multiple sclerosis include the production of antibodies in the central nervous system, expressed as presence of oligoclonal bands and/or an increased immunoglobulin G index-the level of immunoglobulin G in the cerebrospinal fluid compared to serum. However, the underlying...... differences between oligoclonal band-positive and -negative patients with multiple sclerosis and reasons for variability in immunoglobulin G index are not known. To identify genetic factors influencing the variation in the antibody levels in the cerebrospinal fluid in multiple sclerosis, we have performed...... a genome-wide association screen in patients collected from nine countries for two traits, presence or absence of oligoclonal bands (n = 3026) and immunoglobulin G index levels (n = 938), followed by a replication in 3891 additional patients. We replicate previously suggested association signals...

Hsp90 interacts specifically with viral RNA and differentially regulates replication initiation of Bamboo mosaic virus and associated satellite RNA.

Directory of Open Access Journals (Sweden)

Ying Wen Huang

Full Text Available Host factors play crucial roles in the replication of plus-strand RNA viruses. In this report, a heat shock protein 90 homologue of Nicotiana benthamiana, NbHsp90, was identified in association with partially purified replicase complexes from BaMV-infected tissue, and shown to specifically interact with the 3' untranslated region (3' UTR of BaMV genomic RNA, but not with the 3' UTR of BaMV-associated satellite RNA (satBaMV RNA or that of genomic RNA of other viruses, such as Potato virus X (PVX or Cucumber mosaic virus (CMV. Mutational analyses revealed that the interaction occurs between the middle domain of NbHsp90 and domain E of the BaMV 3' UTR. The knockdown or inhibition of NbHsp90 suppressed BaMV infectivity, but not that of satBaMV RNA, PVX, or CMV in N. benthamiana. Time-course analysis further revealed that the inhibitory effect of 17-AAG is significant only during the immediate early stages of BaMV replication. Moreover, yeast two-hybrid and GST pull-down assays demonstrated the existence of an interaction between NbHsp90 and the BaMV RNA-dependent RNA polymerase. These results reveal a novel role for NbHsp90 in the selective enhancement of BaMV replication, most likely through direct interaction with the 3' UTR of BaMV RNA during the initiation of BaMV RNA replication.

Activation of human herpesvirus replication by apoptosis.

Science.gov (United States)

Prasad, Alka; Remick, Jill; Zeichner, Steven L

2013-10-01

A central feature of herpesvirus biology is the ability of herpesviruses to remain latent within host cells. Classically, exposure to inducing agents, like activating cytokines or phorbol esters that stimulate host cell signal transduction events, and epigenetic agents (e.g., butyrate) was thought to end latency. We recently showed that Kaposi's sarcoma-associated herpesvirus (KSHV, or human herpesvirus-8 [HHV-8]) has another, alternative emergency escape replication pathway that is triggered when KSHV's host cell undergoes apoptosis, characterized by the lack of a requirement for the replication and transcription activator (RTA) protein, accelerated late gene kinetics, and production of virus with decreased infectivity. Caspase-3 is necessary and sufficient to initiate the alternative replication program. HSV-1 was also recently shown to initiate replication in response to host cell apoptosis. These observations suggested that an alternative apoptosis-triggered replication program might be a general feature of herpesvirus biology and that apoptosis-initiated herpesvirus replication may have clinical implications, particularly for herpesviruses that almost universally infect humans. To explore whether an alternative apoptosis-initiated replication program is a common feature of herpesvirus biology, we studied cell lines latently infected with Epstein-Barr virus/HHV-4, HHV-6A, HHV-6B, HHV-7, and KSHV. We found that apoptosis triggers replication for each HHV studied, with caspase-3 being necessary and sufficient for HHV replication. An alternative apoptosis-initiated replication program appears to be a common feature of HHV biology. We also found that commonly used cytotoxic chemotherapeutic agents activate HHV replication, which suggests that treatments that promote apoptosis may lead to activation of latent herpesviruses, with potential clinical significance.

Ecology and evolution in the RNA world dynamics and stability of prebiotic replicator systems

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Szilágyi, András; Zachar, István; Scheuring, István

2017-01-01

billion years ago. The many different incarnations of nucleotide sequence (string) replicator models proposed recently are all attempts to explain on this basis how the genetic information transfer and the functional diversity of prebiotic replicator systems may have emerged, persisted and evolved...... into the first living cell. We have postulated three necessary conditions for an RNA World model system to be a dynamically feasible representation of prebiotic chemical evolution: (1) it must maintain and transfer a sufficient diversity of information reliably and indefinitely, (2) it must be ecologically...... stable and (3) it must be evolutionarily stable. In this review, we discuss the best-known prebiotic scenarios and the corresponding models of string-replicator dynamics and assess them against these criteria. We suggest that the most popular of prebiotic replicator systems, the hypercycle, is probably...

Pervasive sharing of genetic effects in autoimmune disease.

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Chris Cotsapas

2011-08-01

Full Text Available Genome-wide association (GWA studies have identified numerous, replicable, genetic associations between common single nucleotide polymorphisms (SNPs and risk of common autoimmune and inflammatory (immune-mediated diseases, some of which are shared between two diseases. Along with epidemiological and clinical evidence, this suggests that some genetic risk factors may be shared across diseases-as is the case with alleles in the Major Histocompatibility Locus. In this work we evaluate the extent of this sharing for 107 immune disease-risk SNPs in seven diseases: celiac disease, Crohn's disease, multiple sclerosis, psoriasis, rheumatoid arthritis, systemic lupus erythematosus, and type 1 diabetes. We have developed a novel statistic for Cross Phenotype Meta-Analysis (CPMA which detects association of a SNP to multiple, but not necessarily all, phenotypes. With it, we find evidence that 47/107 (44% immune-mediated disease risk SNPs are associated to multiple-but not all-immune-mediated diseases (SNP-wise P(CPMA<0.01. We also show that distinct groups of interacting proteins are encoded near SNPs which predispose to the same subsets of diseases; we propose these as the mechanistic basis of shared disease risk. We are thus able to leverage genetic data across diseases to construct biological hypotheses about the underlying mechanism of pathogenesis.

The transcription elongation factor Bur1-Bur2 interacts with replication protein A and maintains genome stability during replication stress

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Clausing, Emanuel; Mayer, Andreas; Chanarat, Sittinan

2010-01-01

Multiple DNA-associated processes such as DNA repair, replication, and recombination are crucial for the maintenance of genome integrity. Here, we show a novel interaction between the transcription elongation factor Bur1-Bur2 and replication protein A (RPA), the eukaryotic single-stranded DNA......-binding protein with functions in DNA repair, recombination, and replication. Bur1 interacted via its C-terminal domain with RPA, and bur1-¿C mutants showed a deregulated DNA damage response accompanied by increased sensitivity to DNA damage and replication stress as well as increased levels of persisting Rad52...... foci. Interestingly, the DNA damage sensitivity of an rfa1 mutant was suppressed by bur1 mutation, further underscoring a functional link between these two protein complexes. The transcription elongation factor Bur1-Bur2 interacts with RPA and maintains genome integrity during DNA replication stress....

The genetic validation of heterogeneity in schizophrenia

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Moritani Makiko

2011-10-01

Full Text Available Abstract Introduction Schizophrenia is a heritable disorder, however clear genetic architecture has not been detected. To overcome this state of uncertainty, the SZGene database has been established by including all published case-control genetic association studies appearing in peer-reviewed journals. In the current study, we aimed to determine if genetic variants strongly suggested by SZGene are associated with risk of schizophrenia in our case-control samples of Japanese ancestry. In addition, by employing the additive model for aggregating the effect of seven variants, we aimed to verify the genetic heterogeneity of schizophrenia diagnosed by an operative diagnostic manual, the DSM-IV. Methods Each positively suggested genetic polymorphism was ranked according to its p-value, then the seven top-ranked variants (p Results No statistically significant deviation between cases and controls was observed in the genetic risk-index derived from all seven variants on the top-ranked polymorphisms. In fact, the average risk-index score in the schizophrenia group (6.5+/-1.57 was slightly lower than among controls (6.6+/-1.39. Conclusion The current work illustrates the difficulty in identifying universal and definitive risk-conferring polymorphisms for schizophrenia. Our employed number of samples was small, so we can not preclude the possibility that some or all of these variants are minor risk factors for schizophrenia in the Japanese population. It is also important to aggregate the updated positive variants in the SZGene database when the replication work is conducted.

Replicating Health Economic Models: Firm Foundations or a House of Cards?

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Bermejo, Inigo; Tappenden, Paul; Youn, Ji-Hee

2017-11-01

Health economic evaluation is a framework for the comparative analysis of the incremental health gains and costs associated with competing decision alternatives. The process of developing health economic models is usually complex, financially expensive and time-consuming. For these reasons, model development is sometimes based on previous model-based analyses; this endeavour is usually referred to as model replication. Such model replication activity may involve the comprehensive reproduction of an existing model or 'borrowing' all or part of a previously developed model structure. Generally speaking, the replication of an existing model may require substantially less effort than developing a new de novo model by bypassing, or undertaking in only a perfunctory manner, certain aspects of model development such as the development of a complete conceptual model and/or comprehensive literature searching for model parameters. A further motivation for model replication may be to draw on the credibility or prestige of previous analyses that have been published and/or used to inform decision making. The acceptability and appropriateness of replicating models depends on the decision-making context: there exists a trade-off between the 'savings' afforded by model replication and the potential 'costs' associated with reduced model credibility due to the omission of certain stages of model development. This paper provides an overview of the different levels of, and motivations for, replicating health economic models, and discusses the advantages, disadvantages and caveats associated with this type of modelling activity. Irrespective of whether replicated models should be considered appropriate or not, complete replicability is generally accepted as a desirable property of health economic models, as reflected in critical appraisal checklists and good practice guidelines. To this end, the feasibility of comprehensive model replication is explored empirically across a small

GRECOS project. The use of genetics to predict the vascular recurrence after stroke

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Fernández-Cadenas, Israel; Mendióroz, Maite; Giralt, Dolors; Nafria, Cristina; Garcia, Elena; Carrera, Caty; Gallego-Fabrega, Cristina; Domingues-Montanari, Sophie; Delgado, Pilar; Ribó, Marc; Castellanos, Mar; Martínez, Sergi; Freijo, Mari Mar; Jiménez-Conde, Jordi; Rubiera, Marta; Alvarez-Sabín, José; Molina, Carlos A.; Font, Maria Angels; Olivares, Marta Grau; Palomeras, Ernest; de la Ossa, Natalia Perez; Martinez-Zabaleta, Maite; Masjuan, Jaime; Moniche, Francisco; Canovas, David; Piñana, Carlos; Purroy, Francisco; Cocho, Dolores; Navas, Inma; Tejero, Carlos; Aymerich, Nuria; Cullell, Natalia; Muiño, Elena; Serena, Joaquín; Rubio, Francisco; Davalos, Antoni; Roquer, Jaume; Arenillas, Juan Francisco; Martí-Fábregas, Joan; Keene, Keith; Chen, Wei-Min; Worrall, Bradford; Sale, Michele; Arboix, Adrià; Krupinski, Jerzy; Montaner, Joan

2017-01-01

Background and Purpose Vascular recurrence occurs in 11% of patients during the first year after ischemic stroke (IS) or transient ischemic attack (TIA). Clinical scores do not predict the whole vascular recurrence risk, therefore we aimed to find genetic variants associated with recurrence that might improve the clinical predictive models in IS. Methods We analyzed 256 polymorphisms from 115 candidate genes in three patient cohorts comprising 4,482 IS or TIA patients. The discovery cohort was prospectively recruited and included 1,494 patients, 6.2% of them developed a new IS during the first year of follow-up. Replication analysis was performed in 2,988 patients using SNPlex or HumanOmni1-Quad technology. We generated a predictive model using Cox regression (GRECOS score), and generated risk groups using a classification tree method. Results The analyses revealed that rs1800801 in the MGP gene (HR: 1.33, p= 9×10−03), a gene related to artery calcification, was associated with new IS during the first year of follow-up. This polymorphism was replicated in a Spanish cohort (n=1.305), however it was not significantly associated in a North American cohort (n=1.683). The GRECOS score predicted new IS (p= 3.2×10−09) and could classify patients, from low risk of stroke recurrence (1.9%) to high risk (12.6%). Moreover, the addition of genetic risk factors to the GRECOS score improves the prediction compared to previous SPI-II score (p=0.03). Conclusions The use of genetics could be useful to estimate vascular recurrence risk after IS. Genetic variability in the MGP gene was associated with vascular recurrence in the Spanish population. PMID:28411264

The scenario on the origin of translation in the RNA world: in principle of replication parsimony

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Ma Wentao

2010-11-01

Full Text Available Abstract Background It is now believed that in the origin of life, proteins should have been "invented" in an RNA world. However, due to the complexity of a possible RNA-based proto-translation system, this evolving process seems quite complicated and the associated scenario remains very blurry. Considering that RNA can bind amino acids with specificity, it has been reasonably supposed that initial peptides might have been synthesized on "RNA templates" containing multiple amino acid binding sites. This "Direct RNA Template (DRT" mechanism is attractive because it should be the simplest mechanism for RNA to synthesize peptides, thus very likely to have been adopted initially in the RNA world. Then, how this mechanism could develop into a proto-translation system mechanism is an interesting problem. Presentation of the hypothesis Here an explanation to this problem is shown considering the principle of "replication parsimony" --- genetic information tends to be utilized in a parsimonious way under selection pressure, due to its replication cost (e.g., in the RNA world, nucleotides and ribozymes for RNA replication. Because a DRT would be quite long even for a short peptide, its replication cost would be great. Thus the diversity and the length of functional peptides synthesized by the DRT mechanism would be seriously limited. Adaptors (proto-tRNAs would arise to allow a DRT's complementary strand (called "C-DRT" here to direct the synthesis of the same peptide synthesized by the DRT itself. Because the C-DRT is a necessary part in the DRT's replication, fewer turns of the DRT's replication would be needed to synthesize definite copies of the functional peptide, thus saving the replication cost. Acting through adaptors, C-DRTs could transform into much shorter templates (called "proto-mRNAs" here and substitute the role of DRTs, thus significantly saving the replication cost. A proto-rRNA corresponding to the small subunit rRNA would then emerge

Genetics of Obesity Traits: A Bivariate Genome-Wide Association Analysis

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Wu, Yili; Duan, Haiping; Tian, Xiaocao

2018-01-01

Previous genome-wide association studies on anthropometric measurements have identified more than 100 related loci, but only a small portion of heritability in obesity was explained. Here we present a bivariate twin study to look for the genetic variants associated with body mass index and waist......-hip ratio, and to explore the obesity-related pathways in Northern Han Chinese. Cholesky decompositionmodel for 242monozygotic and 140 dizygotic twin pairs indicated a moderate genetic correlation (r = 0.53, 95%CI: 0.42–0.64) between body mass index and waist-hip ratio. Bivariate genome-wide association.......05. Expression quantitative trait loci analysis identified rs2242044 as a significant cis-eQTL in both the normal adipose-subcutaneous (P = 1.7 × 10−9) and adipose-visceral (P = 4.4 × 10−15) tissue. These findings may provide an important entry point to unravel genetic pleiotropy in obesity traits....

Social learning and the replication process: an experimental investigation.

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Derex, Maxime; Feron, Romain; Godelle, Bernard; Raymond, Michel

2015-06-07

Human cultural traits typically result from a gradual process that has been described as analogous to biological evolution. This observation has led pioneering scholars to draw inspiration from population genetics to develop a rigorous and successful theoretical framework of cultural evolution. Social learning, the mechanism allowing information to be transmitted between individuals, has thus been described as a simple replication mechanism. Although useful, the extent to which this idealization appropriately describes the actual social learning events has not been carefully assessed. Here, we used a specifically developed computer task to evaluate (i) the extent to which social learning leads to the replication of an observed behaviour and (ii) the consequences it has for fitness landscape exploration. Our results show that social learning does not lead to a dichotomous choice between disregarding and replicating social information. Rather, it appeared that individuals combine and transform information coming from multiple sources to produce new solutions. As a consequence, landscape exploration was promoted by the use of social information. These results invite us to rethink the way social learning is commonly modelled and could question the validity of predictions coming from models considering this process as replicative. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Lack of Associations of CHRNA5-A3-B4 Genetic Variants with Smoking Cessation Treatment Outcomes in Caucasian Smokers despite Associations with Baseline Smoking.

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Rachel F Tyndale

Full Text Available CHRNA5-A3-B4 variants, rs16969968, rs588765 and rs578776, are consistently associated with tobacco consumption among smokers, but the association with smoking cessation is less consistent. Among the studies that reported significant associations with cessation, the effects were observed in smokers treated with placebo treatment in some studies and conversely in those receiving active pharmacological therapy (bupropion and nicotine replacement therapies in others. Thus, it remains unclear whether CHRNA5-A3-B4 is a useful marker for optimizing smoking cessation. Using data from 654 Caucasian smokers treated with placebo, nicotine patch or varenicline, we investigated whether CHRNA5-A3-B4 variants were associated with smoking cessation outcomes, and whether there were significant genotype-by-treatment or haplotype-by-treatment interactions. We observed no significant associations between CHRNA5-A3-B4 variants and smoking cessation, despite replicating previous associations with baseline tobacco consumption. At end of treatment the effect size on smoking cessation in the placebo, patch and varenicline groups for rs16969968 [GG vs. GA+AA] was OR = 0.66 (P = 0.23, OR = 1.01 (P = 0.99, and OR = 1.30 (P = 0.36 respectively, of rs588765 [CC vs. CT+TT] was OR = 0.96 (P = 0.90, OR = 0.84 (P = 0.58, and OR = 0.74 (P = 0.29 respectively, and for rs578776 [GG vs. GA+AA] on smoking cessation was OR = 1.02 (P = 0.95, OR = 0.75 (P = 0.35, and OR = 1.20 (P = 0.51 respectively. Furthermore, we observed no associations with cessation using the CHRNA5-A3-B4 haplotype (constructed using rs16969968 and rs588765, nor did we observe any significant genotype-by-treatment interactions, with or without adjusting for the rate of nicotine metabolism (all P>0.05. We also observed no significant genetic associations with 6 month or 12 month smoking abstinence. In conclusion, we found no association between CHRNA5-A3-B4 variants and smoking cessation rates in this clinical