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Sample records for m19 mutated allele

  1. A common mutation associated with the Duarte galactosemia allele

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

    1994-06-01

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

  2. A new mutation for Huntington disease following maternal transmission of an intermediate allele

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    Semaka, Alicia; Kay, Chris; Belfroid, René D. M.; Bijlsma, Emilia K.; Losekoot, Monique; van Langen, Irene M.; van Maarle, Merel C.; Oosterloo, Mayke; Hayden, Michael R.; van Belzen, Martine J.

    2015-01-01

    New mutations for Huntington disease (HD) originate from CAG repeat expansion of intermediate alleles (27-35 CAG). Expansions of such alleles into the pathological range (≥ 36 CAG) have been exclusively observed in paternal transmission. We report the occurrence of a new mutation that defies the

  3. Severe complications in a child with achondroplasia and two FGFR3 mutations on the same allele

    NARCIS (Netherlands)

    Rump, P; Letteboer, TGW; Gille, JJP; Torringa, MJL; Baerts, W; van Gestel, JPJ; Verheij, JBGM; van Essen, AJ

    2006-01-01

    We describe a unique case of achondroplasia with associated complications, including severe respiratory problems. Molecular analysis of the fibroblast growth factor receptor type 3 (FGFR3) gene in this patient showed the common p.G380R mutation and a second novel p.L377R Mutation. An allele-specific

  4. Detection of MPL mutations by a novel allele-specific PCR-based strategy.

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    Furtado, Larissa V; Weigelin, Helmut C; Elenitoba-Johnson, Kojo S J; Betz, Bryan L

    2013-11-01

    MPL mutation testing is recommended in patients with suspected primary myelofibrosis or essential thrombocythemia who lack the JAK2 V617F mutation. MPL mutations can occur at allelic levels below 15%, which may escape detection by commonly used mutation screening methods such as Sanger sequencing. We developed a novel multiplexed allele-specific PCR assay capable of detecting most recurrent MPL exon 10 mutations associated with primary myelofibrosis and essential thrombocythemia (W515L, W515K, W515A, and S505N) down to a sensitivity of 2.5% mutant allele. Test results were reviewed from 15 reference cases and 1380 consecutive specimens referred to our laboratory for testing. Assay performance was compared to Sanger sequencing across a series of 58 specimens with MPL mutations. Positive cases consisted of 45 with W515L, 6 with S505N, 5 with W515K, 1 with W515A, and 1 with both W515L and S505N. Seven cases had mutations below 5% that were undetected by Sanger sequencing. Ten additional cases had mutation levels between 5% and 15% that were not consistently detected by sequencing. All results were easily interpreted in the allele-specific test. This assay offers a sensitive and reliable solution for MPL mutation testing. Sanger sequencing appears insufficiently sensitive for robust MPL mutation detection. Our data also suggest the relative frequency of S505N mutations may be underestimated, highlighting the necessity for inclusion of this mutation in MPL test platforms. Copyright © 2013 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  5. Highly preferential association of NonF508del CF mutations with the M470 allele.

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    Ciminelli, B M; Bonizzato, A; Bombieri, C; Pompei, F; Gabaldo, M; Ciccacci, C; Begnini, A; Holubova, A; Zorzi, P; Piskackova, T; Macek, M; Castellani, C; Modiano, G; Pignatti, P F

    2007-01-01

    On the basis of previous findings on random individuals, we hypothesized a preferential association of CF causing mutations with the M allele of the M470V polymorphic site of the CFTR gene. We have determined the M/V-CF mutation haplotype in a series of 201 North East Italian and 73 Czech CF patients who were not F508del homozygotes, as F508del was already known to be fully associated with the M allele. Out of 358 not F508del CF genes, 84 carried the V allele and 274 the less common M allele. In the N-E Italian population, MM subjects have a risk of carrying a CF causing mutation 6.9x greater than VV subjects when F508del is excluded and 15.4x when F508del is included. In the Czech population a similar, although less pronounced, association is observed. Besides the possible biological significance of this association, the possibility of exploiting it for a pilot screening program has been explored in a local North East Italian population for which CF patients were characterized for their CF mutation. General M470V genotyping followed by common CF mutation screening limited to couples in which each partner carries at least one M allele would need testing only 39% of the couples, which contribute 89% of the total risk, with a cost benefit.

  6. JAK2V617F mutation is associated with special alleles in essential thrombocythemia.

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    Hsiao, Hui-Hua; Liu, Yi-Chang; Tsai, Hui-Jen; Lee, Ching-Ping; Hsu, Jui-Feng; Lin, Sheng-Fung

    2011-03-01

    Janus kinase 2 mutation (JAK2V617F) has been identified in myeloproliferative neoplasms. Furthermore, special single nucleoside polymorphisms (SNPs) have been found to be associated with the JAK2V617F mutation. Therefore, the associations among JAK2V617F and special SNPs and the allelic location between them were investigated in patients with essential thrombocythemia (ET). A total of 61 patients with ET and 106 healthy individuals were enrolled. The PCR-RFLP method was applied to investigate the pattern of three SNPs, rs10974944, rs12343867, and rs12340895. Allele-specific PCR was used to examine the allelic location between rs10974944 and JAK2V617F. Among the patients with ET, 34 (55.7%, 34/61) were JAK2V617F positive (heterozygous) while the other 27 (44.3%, 27/61) were negative, and there were no MPLW515L/K mutations noted. The pattern of special SNPs in JAK2V617F(+) was significantly different from that in normal individuals (p <0.05), while there was no difference between JAK2V617F(-) patients and normal individuals. Allele-specific PCR showed high association of a cis-location between the special G-allele of rs10974944 and JAK2V617F(+). Based on this small numbered study, the results show the association between special SNPs and JAK2V617F mutation and a cis-location between the special G-allelic form of rs10974944 and the JAK2V617F mutation. These data highlight a close relationship between them in patients with ET.

  7. The allele-frequency spectrum in a decoupled Moran model with mutation, drift, and directional selection, assuming small mutation rates.

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    Vogl, Claus; Clemente, Florian

    2012-05-01

    We analyze a decoupled Moran model with haploid population size N, a biallelic locus under mutation and drift with scaled forward and backward mutation rates θ(1)=μ(1)N and θ(0)=μ(0)N, and directional selection with scaled strength γ=sN. With small scaled mutation rates θ(0) and θ(1), which is appropriate for single nucleotide polymorphism data in highly recombining regions, we derive a simple approximate equilibrium distribution for polymorphic alleles with a constant of proportionality. We also put forth an even simpler model, where all mutations originate from monomorphic states. Using this model we derive the sojourn times, conditional on the ancestral and fixed allele, and under equilibrium the distributions of fixed and polymorphic alleles and fixation rates. Furthermore, we also derive the distribution of small samples in the diffusion limit and provide convenient recurrence relations for calculating this distribution. This enables us to give formulas analogous to the Ewens-Watterson estimator of θ for biased mutation rates and selection. We apply this theory to a polymorphism dataset of fourfold degenerate sites in Drosophila melanogaster. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. An Allelic Series of Trp63 Mutations Defines TAp63 as a Modifier of EEC Syndrome

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    Lindahl, Emma Vernersson; Garcia, Elvin L.; Mills, Alea A.

    2014-01-01

    Human Ectrodactyly, Ectodermal dysplasia, Clefting (EEC) syndrome is an autosomal dominant developmental disorder defined by limb deformities, skin defects, and craniofacial clefting. Although associated with heterozygous missense mutations in TP63, the genetic basis underlying the variable expressivity and incomplete penetrance of EEC is unknown. Here we show that mice heterozygous for an allele encoding the Trp63 p.Arg318His mutation, which corresponds to the human TP63 p.Arg279His mutation found in patients with EEC, have features of human EEC. Using an allelic series, we discovered that whereas clefting and skin defects are caused by loss of Trp63 function, limb anomalies are due to gain- and/or dominant-negative effects of Trp63. Furthermore, we identify TAp63 as a strong modifier of EEC-associated phenotypes with regard to both penetrance and expressivity. PMID:23775923

  9. Allele-Specific Chromatin Recruitment and Therapeutic Vulnerabilities of ESR1 Activating Mutations.

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    Jeselsohn, Rinath; Bergholz, Johann S; Pun, Matthew; Cornwell, MacIntosh; Liu, Weihan; Nardone, Agostina; Xiao, Tengfei; Li, Wei; Qiu, Xintao; Buchwalter, Gilles; Feiglin, Ariel; Abell-Hart, Kayley; Fei, Teng; Rao, Prakash; Long, Henry; Kwiatkowski, Nicholas; Zhang, Tinghu; Gray, Nathanael; Melchers, Diane; Houtman, Rene; Liu, X Shirley; Cohen, Ofir; Wagle, Nikhil; Winer, Eric P; Zhao, Jean; Brown, Myles

    2018-02-12

    Estrogen receptor α (ER) ligand-binding domain (LBD) mutations are found in a substantial number of endocrine treatment-resistant metastatic ER-positive (ER + ) breast cancers. We investigated the chromatin recruitment, transcriptional network, and genetic vulnerabilities in breast cancer models harboring the clinically relevant ER mutations. These mutants exhibit both ligand-independent functions that mimic estradiol-bound wild-type ER as well as allele-specific neomorphic properties that promote a pro-metastatic phenotype. Analysis of the genome-wide ER binding sites identified mutant ER unique recruitment mediating the allele-specific transcriptional program. Genetic screens identified genes that are essential for the ligand-independent growth driven by the mutants. These studies provide insights into the mechanism of endocrine therapy resistance engendered by ER mutations and potential therapeutic targets. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Mutation Rate Variation is a Primary Determinant of the Distribution of Allele Frequencies in Humans.

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    Arbel Harpak

    2016-12-01

    Full Text Available The site frequency spectrum (SFS has long been used to study demographic history and natural selection. Here, we extend this summary by examining the SFS conditional on the alleles found at the same site in other species. We refer to this extension as the "phylogenetically-conditioned SFS" or cSFS. Using recent large-sample data from the Exome Aggregation Consortium (ExAC, combined with primate genome sequences, we find that human variants that occurred independently in closely related primate lineages are at higher frequencies in humans than variants with parallel substitutions in more distant primates. We show that this effect is largely due to sites with elevated mutation rates causing significant departures from the widely-used infinite sites mutation model. Our analysis also suggests substantial variation in mutation rates even among mutations involving the same nucleotide changes. In summary, we show that variable mutation rates are key determinants of the SFS in humans.

  11. Novel allelic mutations in murine Serca2 induce differential development of squamous cell tumors

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    Toki, Hideaki; Minowa, Osamu; Inoue, Maki; Motegi, Hiromi; Karashima, Yuko; Ikeda, Ami [Team for Advanced Development and Evaluation of Human Disease Models, Riken BioResource Center (BRC), Tsukuba, Ibaraki (Japan); Kaneda, Hideki [Technology and Development Team for Mouse Phenotype Analysis, Riken BRC, Tsukuba, Ibaraki (Japan); Sakuraba, Yoshiyuki [Mutagenesis and Genomics Team, Riken BRC, Tsukuba, Ibaraki (Japan); Saiki, Yuriko [Department of Molecular Pathology, Tohoku University Graduate School of Medicine, Sendai, Miyagi (Japan); Wakana, Shigeharu [Technology and Development Team for Mouse Phenotype Analysis, Riken BRC, Tsukuba, Ibaraki (Japan); Suzuki, Hiroshi [Department of Biochemistry, Asahikawa Medical University, Asahikawa, Hokkaido (Japan); Gondo, Yoichi [Mutagenesis and Genomics Team, Riken BRC, Tsukuba, Ibaraki (Japan); Shiroishi, Toshihiko [Mammalian Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka (Japan); Noda, Tetsuo, E-mail: tnoda@jfcr.or.jp [Team for Advanced Development and Evaluation of Human Disease Models, Riken BioResource Center (BRC), Tsukuba, Ibaraki (Japan); Department of Cell Biology, Cancer Institute, The Japanese Foundation for Cancer Research, Tokyo (Japan)

    2016-08-05

    Dominant mutations in the Serca2 gene, which encodes sarco(endo)plasmic reticulum calcium-ATPase, predispose mice to gastrointestinal epithelial carcinoma [1–4] and humans to Darier disease (DD) [14–17]. In this study, we generated mice harboring N-ethyl-N-nitrosourea (ENU)-induced allelic mutations in Serca2: three missense mutations and one nonsense mutation. Mice harboring these Serca2 mutations developed tumors that were categorized as either early onset squamous cell tumors (SCT), with development similar to null-type knockout mice [2,4] (aggressive form; M682, M814), or late onset tumors (mild form; M1049, M1162). Molecular analysis showed no aberration in Serca2 mRNA or protein expression levels in normal esophageal cells of any of the four mutant heterozygotes. There was no loss of heterozygosity at the Serca2 locus in the squamous cell carcinomas in any of the four lines. The effect of each mutation on Ca{sup 2+}-ATPase activity was predicted using atomic-structure models and accumulated mutated protein studies, suggesting that putative complete loss of Serca2 enzymatic activity may lead to early tumor onset, whereas mutations in which Serca2 retains residual enzymatic activity result in late onset. We propose that impaired Serca2 gene product activity has a long-term effect on squamous cell carcinogenesis from onset to the final carcinoma stage through an as-yet unrecognized but common regulatory pathway. -- Highlights: •Novel mutations in murine Serca2 caused early onset or late onset of tumorigenesis. •They also caused higher or lower incidence of Darier Disease phenotype. •3D structure model suggested the former mutations led to severer defect on ATPase. •Driver gene mutations via long-range effect on Ca2+ distributions are suggested.

  12. Analysis of HFE gene mutations and HLA-A alleles in Brazilian patients with iron overload

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    Rodolfo Delfini Cançado

    Full Text Available CONTEXT AND OBJECTIVE: Hemochromatosis is a common inherited disorder of iron metabolism and one of the most important causes of iron overload. The objective was to analyze the presence of C282Y, H63D and S65C mutations in the HFE gene and HLA-A alleles for a group of Brazilian patients with iron overload, and to correlate genotype with clinical and laboratory variables. DESIGN AND SETTING: Prospective study, in Discipline of Hematology and Oncology, Faculdade de Ciências Médicas da Santa Casa de Misericórdia de São Paulo. METHODS: We studied 35 patients with iron overload seen at our outpatient unit between January 2001 and December 2003. Fasting levels of serum iron and ferritin, and total iron-binding capacity, were assayed using standard techniques. Determinations of C282Y, H63D and S65C mutations in the HFE gene and of HLA-A alleles were performed by polymerase chain reaction (PCR. RESULTS: Twenty-six out of 35 patients (74% presented at least one of the HFE gene mutations analyzed. Among these, five (14% were C282Y/C282Y, four (11% C282Y/H63D, one (3% H63D/H63D, six (17% C282Y/WT and ten (29% H63D/WT. No patients had the S65C mutation and nine (25% did not present any of the three HFE mutations. Four out of five patients with C282Y/C282Y genotype (80% and three out of four patients with C282Y/H63D genotype (75% were HLA A*03. CONCLUSION: Analysis of HFE gene mutations constitutes an important procedure in identifying patients with hereditary hemochromatosis, particularly for patients with iron overload.

  13. Allelic heterogeneity of FGF5 mutations causes the long-hair phenotype in dogs.

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    Dierks, C; Mömke, S; Philipp, U; Distl, O

    2013-08-01

    Hitherto, the only known mutant gene leading to the long-hair phenotype in mammals is the fibroblast growth factor 5 (FGF5). In many dog breeds, the previously discovered FGF5:p.Cys95Phe mutation appeared completely concordant with the long-hair phenotype, but for some breeds, the long-hair phenotype could not be resolved. First, we studied the role of the FGF5:p.Cys95Phe and FGF5:g.145_150dupACCAGC mutations in 268 dogs descending from 27 breeds and seven wolves. As these mutations did not explain all the long-hair phenotypes, all exons and their neighbouring regions of FGF5 were re-sequenced. We detected three novel mutations in the coding sequence and one novel non-coding splice-site mutation in FGF5 associated with the long-hair phenotype. The FGF5:p.Ala193Val polymorphism was perfectly consistent with long hair in Akitas and probably in Siberian huskies, too. Dogs of the long-hair breed Samoyed were either homozygous or compound heterozygous for the FGF5:p.Ala193Val or the FGF5:p.Cys95Phe polymorphisms respectively. The two newly detected polymorphisms FGF5:c.559_560dupGG and FGF5:g.8193T>A and the known mutation FGF5:p.Cys95Phe explained the long-hair phenotype of all Afghan hounds analysed. An FGF5:c.556_571del16 mutation was found in one longhaired Eurasier. All long-hair-associated mutations follow a recessive mode of inheritance, and allelic heterogeneity was a common finding in breeds other than Akita. © 2013 The Authors, Animal Genetics © 2013 Stichting International Foundation for Animal Genetics.

  14. An approximate stationary solution for multi-allele neutral diffusion with low mutation rates.

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    Burden, Conrad J; Tang, Yurong

    2016-12-01

    We address the problem of determining the stationary distribution of the multi-allelic, neutral-evolution Wright-Fisher model in the diffusion limit. A full solution to this problem for an arbitrary K×K mutation rate matrix involves solving for the stationary solution of a forward Kolmogorov equation over a (K-1)-dimensional simplex, and remains intractable. In most practical situations mutations rates are slow on the scale of the diffusion limit and the solution is heavily concentrated on the corners and edges of the simplex. In this paper we present a practical approximate solution for slow mutation rates in the form of a set of line densities along the edges of the simplex. The method of solution relies on parameterising the general non-reversible rate matrix as the sum of a reversible part and a set of (K-1)(K-2)/2 independent terms corresponding to fluxes of probability along closed paths around faces of the simplex. The solution is potentially a first step in estimating non-reversible evolutionary rate matrices from observed allele frequency spectra. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Detection of MPLW515L/K mutations and determination of allele frequencies with a single-tube PCR assay.

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    Takei, Hiraku; Morishita, Soji; Araki, Marito; Edahiro, Yoko; Sunami, Yoshitaka; Hironaka, Yumi; Noda, Naohiro; Sekiguchi, Yuji; Tsuneda, Satoshi; Ohsaka, Akimichi; Komatsu, Norio

    2014-01-01

    A gain-of-function mutation in the myeloproliferative leukemia virus (MPL) gene, which encodes the thrombopoietin receptor, has been identified in patients with essential thrombocythemia and primary myelofibrosis, subgroups of classic myeloproliferative neoplasms (MPNs). The presence of MPL gene mutations is a critical diagnostic criterion for these diseases. Here, we developed a rapid, simple, and cost-effective method of detecting two major MPL mutations, MPLW515L/K, in a single PCR assay; we termed this method DARMS (dual amplification refractory mutation system)-PCR. DARMS-PCR is designed to produce three different PCR products corresponding to MPLW515L, MPLW515K, and all MPL alleles. The amplicons are later detected and quantified using a capillary sequencer to determine the relative frequencies of the mutant and wild-type alleles. Applying DARMS-PCR to human specimens, we successfully identified MPL mutations in MPN patients, with the exception of patients bearing mutant allele frequencies below the detection limit (5%) of this method. The MPL mutant allele frequencies determined using DARMS-PCR correlated strongly with the values determined using deep sequencing. Thus, we demonstrated the potential of DARMS-PCR to detect MPL mutations and determine the allele frequencies in a timely and cost-effective manner.

  16. Detection of MPLW515L/K mutations and determination of allele frequencies with a single-tube PCR assay.

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    Hiraku Takei

    Full Text Available A gain-of-function mutation in the myeloproliferative leukemia virus (MPL gene, which encodes the thrombopoietin receptor, has been identified in patients with essential thrombocythemia and primary myelofibrosis, subgroups of classic myeloproliferative neoplasms (MPNs. The presence of MPL gene mutations is a critical diagnostic criterion for these diseases. Here, we developed a rapid, simple, and cost-effective method of detecting two major MPL mutations, MPLW515L/K, in a single PCR assay; we termed this method DARMS (dual amplification refractory mutation system-PCR. DARMS-PCR is designed to produce three different PCR products corresponding to MPLW515L, MPLW515K, and all MPL alleles. The amplicons are later detected and quantified using a capillary sequencer to determine the relative frequencies of the mutant and wild-type alleles. Applying DARMS-PCR to human specimens, we successfully identified MPL mutations in MPN patients, with the exception of patients bearing mutant allele frequencies below the detection limit (5% of this method. The MPL mutant allele frequencies determined using DARMS-PCR correlated strongly with the values determined using deep sequencing. Thus, we demonstrated the potential of DARMS-PCR to detect MPL mutations and determine the allele frequencies in a timely and cost-effective manner.

  17. How well do you know your mutation? Complex effects of genetic background on expressivity, complementation, and ordering of allelic effects.

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    Christopher H Chandler

    2017-11-01

    Full Text Available For a given gene, different mutations influence organismal phenotypes to varying degrees. However, the expressivity of these variants not only depends on the DNA lesion associated with the mutation, but also on factors including the genetic background and rearing environment. The degree to which these factors influence related alleles, genes, or pathways similarly, and whether similar developmental mechanisms underlie variation in the expressivity of a single allele across conditions and among alleles is poorly understood. Besides their fundamental biological significance, these questions have important implications for the interpretation of functional genetic analyses, for example, if these factors alter the ordering of allelic series or patterns of complementation. We examined the impact of genetic background and rearing environment for a series of mutations spanning the range of phenotypic effects for both the scalloped and vestigial genes, which influence wing development in Drosophila melanogaster. Genetic background and rearing environment influenced the phenotypic outcome of mutations, including intra-genic interactions, particularly for mutations of moderate expressivity. We examined whether cellular correlates (such as cell proliferation during development of these phenotypic effects matched the observed phenotypic outcome. While cell proliferation decreased with mutations of increasingly severe effects, surprisingly it did not co-vary strongly with the degree of background dependence. We discuss these findings and propose a phenomenological model to aid in understanding the biology of genes, and how this influences our interpretation of allelic effects in genetic analysis.

  18. The Charles River "hairless" rat mutation is distinct from the hairless mouse alleles.

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    Panteleyev, A A; Christiano, A M

    2001-02-01

    The Charles River (CR) "hairless" rat is one of the autosomal recessive hypotrichotic animal models actively studied in pharmacologic and dermatologic research. Despite its widespread use, the molecular basis of this monogenic mutation remains unknown, and the skin histologic features of this phenotype have never been described. However, the designation "hairless" has been used as an extension of the hairless mouse (hr) nomenclature on the basis of the clinical absence of hairs in both phenotypes. We present a description of the histopathologic changes in heterozygous and homozygous CR hairless rat mutants during the first month of life. The postnatal homozygous rat skin was characterized by abnormal keratinization of the hair shaft and formation of a thick and dense layer of corneocytes in the lower portion of the epidermal stratum corneum. This layer prevented the improperly keratinized hair shaft from penetrating the skin surface. Starting from the latest stages of hair follicle (HF) development, obvious signs of HF degeneration were observed in homozygous skin. This process was extremely rapid, and by day 12, mainly atrophic HFs with abnormal or broken hairs were present in the skin. Therefore, the mutation in the CR rat abrogates cell proliferation in the hair matrix and affects keratinocyte differentiation in the HF and interfollicular epidermis, a phenotype that is completely distinct from hr/hr. To test whether the CR rat harbored a mutation in the hr gene, we analyzed the coding region of this gene and consensus intron splice site sequences in mutant rats and found no mutation, further supporting phenotypic evidence that the hairless phenotype in CR rats is not allelic with hairless. Finally, using intragenic polymorphisms, we were able to exclude homozygosity at the hairless locus by use of genotypic analysis. Thus, morphologic analysis of successive stages of phenotype development in the CR hairless rat, together with definitive molecular studies

  19. The Charles River "hairless" rat mutation maps to chromosome 1: allelic with fuzzy and a likely orthologue of mouse frizzy.

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    Ahearn, K; Akkouris, G; Berry, P R; Chrissluis, R R; Crooks, I M; Dull, A K; Grable, S; Jeruzal, J; Lanza, J; Lavoie, C; Maloney, R A; Pitruzzello, M; Sharma, R; Stoklasek, T A; Tweeddale, J; King, T R

    2002-01-01

    Recent evidence has indicated that the recessive mutation affecting hypotrichosis in the Charles River (CR) "hairless" rat does not involve the hairless gene (hr) on rat chromosome 15. To determine if this mutation might be allelic (or orthologous) with any other previously mapped hypotrichosis-generating mutation in mammals, we have produced a panel of backcross rats segregating for the CR hairless rat mutation as well as numerous other markers from throughout the rat genome. Analysis of this panel has located the CR hairless rat's hypotrichosis-generating mutation on chromosome 1, near Myl2, where only the fuzzy mutation in rat (fz) and the frizzy mutation in mouse (fr) have been previously localized. Intercrossing fz/fz and CR hairless rats produced hybrid offspring with abnormal hair, showing that these two rat mutations are allelic. We suggest that the CR hairless rat mutation and fuzzy be renamed frizzy-Charles River (fr(CR)) and frizzy-Harlan (fr(H)), respectively, to reflect their likely orthology with the mouse fr mutation.

  20. Bi-allelic Mutations in PKD1L1 Are Associated with Laterality Defects in Humans.

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    Vetrini, Francesco; D'Alessandro, Lisa C A; Akdemir, Zeynep C; Braxton, Alicia; Azamian, Mahshid S; Eldomery, Mohammad K; Miller, Kathryn; Kois, Chelsea; Sack, Virginia; Shur, Natasha; Rijhsinghani, Asha; Chandarana, Jignesh; Ding, Yan; Holtzman, Judy; Jhangiani, Shalini N; Muzny, Donna M; Gibbs, Richard A; Eng, Christine M; Hanchard, Neil A; Harel, Tamar; Rosenfeld, Jill A; Belmont, John W; Lupski, James R; Yang, Yaping

    2016-10-06

    Disruption of the establishment of left-right (L-R) asymmetry leads to situs anomalies ranging from situs inversus totalis (SIT) to situs ambiguus (heterotaxy). The genetic causes of laterality defects in humans are highly heterogeneous. Via whole-exome sequencing (WES), we identified homozygous mutations in PKD1L1 from three affected individuals in two unrelated families. PKD1L1 encodes a polycystin-1-like protein and its loss of function is known to cause laterality defects in mouse and medaka fish models. Family 1 had one fetus and one deceased child with heterotaxy and complex congenital heart malformations. WES identified a homozygous splicing mutation, c.6473+2_6473+3delTG, which disrupts the invariant splice donor site in intron 42, in both affected individuals. In the second family, a homozygous c.5072G>C (p.Cys1691Ser) missense mutation was detected in an individual with SIT and congenital heart disease. The p.Cys1691Ser substitution affects a highly conserved cysteine residue and is predicted by molecular modeling to disrupt a disulfide bridge essential for the proper folding of the G protein-coupled receptor proteolytic site (GPS) motif. Damaging effects associated with substitutions of this conserved cysteine residue in the GPS motif have also been reported in other genes, namely GPR56, BAI3, and PKD1 in human and lat-1 in C. elegans, further supporting the likely pathogenicity of p.Cys1691Ser in PKD1L1. The identification of bi-allelic PKD1L1 mutations recapitulates previous findings regarding phenotypic consequences of loss of function of the orthologous genes in mice and medaka fish and further expands our understanding of genetic contributions to laterality defects in humans. Copyright © 2016 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  1. Mutation rate heterogeneity and the generation of allele diversity at the human minisatellite MS205 (D16S309).

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    May, C A; Jeffreys, A J; Armour, J A

    1996-11-01

    Many tandemly repeated minisatellite loci display extreme levels of length variation as a consequence of high rates of spontaneous germline mutation altering repeat copy number. Direct screening for new allele lengths by small-pool PCR has shown that instability at the human minisatellite locus MS205 (D16S309) is largely germline specific and usually results in the gain or loss of just a few repeat units. Structural analysis of the order of variant repeats has shown that these events occur preferentially at one end of the tandem array and can result in complex rearrangements including the inter-allelic transfer of repeat units. In contrast, putative mutants recovered from somatic DNA occur at a substantially lower rate and are simple and non-polar in nature. Germline mutation rates vary considerably between alleles, consistent with regulation occurring in cis. Although examination of DNA sequence polymorphisms immediately flanking the minisatellite reveals no definitive associations with germline mutation rate variation, differences in rate may be paralleled by changes in mutation spectrum. These findings help to explain the diversity of MS205 allele structures in modern humans and suggest a common mutation pathway with some other minisatellites.

  2. SSR allelic variation of rice variety Hangxiangnuo bred by space mutation

    International Nuclear Information System (INIS)

    Yang Tifeng; Liu Chuanguang; Pan Dajian; Fan Zhilan; Li Chen; Chen Jianyou; Liu Bin; Jiang Yijun; Gao Yun; Zhou Hanqin

    2011-01-01

    Hangxiangnuo, an indica fragrant glutinous rice mutant, was induced by space environment. Comparing with its wild type Nanfengnuo, the yield and blast resistance of Hangxiangnuo are improved significantly and the grain shape became slender and with fragrance. To understand the mechanisms of space mutation and identify the changes at molecular level associated with phenotypic variations, SSR allelic variation analysis were performed on Hangxiangnuo and Nanfengnuo in this study. The results showed that 45 loci were polymorphic among the 156 SSR loci tested throughout the genome, the frequency of variation was 28.85%. Among the polymorphic loci, 42 loci only showed variations in the molecular weight of the amplified bands, only on locus increased the number of amplification bands in Hangxiangnuo and two loci were differed by heterozygous loci (with two amplification bands at one locus) detected in Nanfengnuo and homozygous loci in Hangxiangnuo. It suggests that the change of some loci in mutants was due to the normal segregation and recombination of heterozygous loci of the wild type. The variation frequencies among different chromosomes were quite different, with the highest one at 50.00% detected on chromosomes 7, 8 and 12, and the lowest at 6.25% on chromosome 6. The polymorphic loci were clustered on chromosomes throughout the genome indicating that large DNA segments mutation is one of the major variation patterns induced by space environment. Some of reported QTLs involved in grain shape, yield, fragrance and blast resistance were found to be located exactly in the mutated regions. Therefore, further study is needed to confirm that these QTLs are responsible for the trait variations. (authors)

  3. Mutation Spectrum of the ABCA4 Gene in a Greek Cohort with Stargardt Disease: Identification of Novel Mutations and Evidence of Three Prevalent Mutated Alleles

    Directory of Open Access Journals (Sweden)

    Kamakari Smaragda

    2018-01-01

    Full Text Available Aim. To evaluate the frequency and pattern of disease-associated mutations of ABCA4 gene among Greek patients with presumed Stargardt disease (STGD1. Materials and Methods. A total of 59 patients were analyzed for ABCA4 mutations using the ABCR400 microarray and PCR-based sequencing of all coding exons and flanking intronic regions. MLPA analysis as well as sequencing of two regions in introns 30 and 36 reported earlier to harbor deep intronic disease-associated variants was used in 4 selected cases. Results. An overall detection rate of at least one mutant allele was achieved in 52 of the 59 patients (88.1%. Direct sequencing improved significantly the complete characterization rate, that is, identification of two mutations compared to the microarray analysis (93.1% versus 50%. In total, 40 distinct potentially disease-causing variants of the ABCA4 gene were detected, including six previously unreported potentially pathogenic variants. Among the disease-causing variants, in this cohort, the most frequent was c.5714+5G>A representing 16.1%, while p.Gly1961Glu and p.Leu541Pro represented 15.2% and 8.5%, respectively. Conclusions. By using a combination of methods, we completely molecularly diagnosed 48 of the 59 patients studied. In addition, we identified six previously unreported, potentially pathogenic ABCA4 mutations.

  4. The Pleiotropic Phenotype of Apc Mutations in the Mouse: Allele Specificity and Effects of the Genetic Background

    Science.gov (United States)

    Halberg, Richard B.; Chen, Xiaodi; Amos-Landgraf, James M.; White, Alanna; Rasmussen, Kristin; Clipson, Linda; Pasch, Cheri; Sullivan, Ruth; Pitot, Henry C.; Dove, William F.

    2008-01-01

    Familial adenomatous polyposis (FAP) is a human cancer syndrome characterized by the development of hundreds to thousands of colonic polyps and extracolonic lesions including desmoid fibromas, osteomas, epidermoid cysts, and congenital hypertrophy of the pigmented retinal epithelium. Afflicted individuals are heterozygous for mutations in the APC gene. Detailed investigations of mice heterozygous for mutations in the ortholog Apc have shown that other genetic factors strongly influence the phenotype. Here we report qualitative and quantitative modifications of the phenotype of Apc mutants as a function of three genetic variables: Apc allele, p53 allele, and genetic background. We have found major differences between the Apc alleles Min and 1638N in multiplicity and regionality of intestinal tumors, as well as in incidence of extracolonic lesions. By contrast, Min mice homozygous for either of two different knockout alleles of p53 show similar phenotypic effects. These studies illustrate the classic principle that functional genetics is enriched by assessing penetrance and expressivity with allelic series. The mouse permits study of an allelic gene series on multiple genetic backgrounds, thereby leading to a better understanding of gene action in a range of biological processes. PMID:18723878

  5. Common breast cancer-predisposition alleles are associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers

    DEFF Research Database (Denmark)

    Antoniou, Antonis C; Spurdle, Amanda B; Sinilnikova, Olga M

    2008-01-01

    Germline mutations in BRCA1 and BRCA2 confer high risks of breast cancer. However, evidence suggests that these risks are modified by other genetic or environmental factors that cluster in families. A recent genome-wide association study has shown that common alleles at single nucleotide polymorp...

  6. Ovarian cancer susceptibility alleles and risk of ovarian cancer in BRCA1 and BRCA2 mutation carriers

    DEFF Research Database (Denmark)

    Ramus, Susan J; Antoniou, Antonis C; Kuchenbaecker, Karoline B

    2012-01-01

    Germline mutations in BRCA1 and BRCA2 are associated with increased risks of breast and ovarian cancer. A genome-wide association study (GWAS) identified six alleles associated with risk of ovarian cancer for women in the general population. We evaluated four of these loci as potential modifiers ...

  7. Ovarian cancer susceptibility alleles and risk of ovarian cancer in BRCA1 and BRCA2 mutation carriers

    NARCIS (Netherlands)

    Ramus, Susan J.; Antoniou, Antonis C.; Kuchenbaecker, Karoline B.; Soucy, Penny; Beesley, Jonathan; Chen, Xiaoqing; McGuffog, Lesley; Sinilnikova, Olga M.; Healey, Sue; Barrowdale, Daniel; Lee, Andrew; Thomassen, Mads; Gerdes, Anne-Marie; Kruse, Torben A.; Jensen, Uffe Birk; Skytte, Anne-Bine; Caligo, Maria A.; Liljegren, Annelie; Lindblom, Annika; Olsson, Håkan; Kristoffersson, Ulf; Stenmark-Askmalm, Marie; Melin, Beatrice; Domchek, Susan M.; Nathanson, Katherine L.; Rebbeck, Timothy R.; Jakubowska, Anna; Lubinski, Jan; Jaworska, Katarzyna; Durda, Katarzyna; Złowocka, Elżbieta; Gronwald, Jacek; Huzarski, Tomasz; Byrski, Tomasz; Cybulski, Cezary; Toloczko-Grabarek, Aleksandra; Osorio, Ana; Benitez, Javier; Duran, Mercedes; Tejada, Maria-Isabel; Hamann, Ute; Rookus, Matti; van Leeuwen, Flora E.; Aalfs, Cora M.; Meijers-Heijboer, Hanne E. J.; van Asperen, Christi J.; van Roozendaal, K. E. P.; Hoogerbrugge, Nicoline; Collée, J. Margriet; Kriege, Mieke; van der Luijt, Rob B.; Peock, Susan; Frost, Debra; Ellis, Steve D.; Platte, Radka; Fineberg, Elena; Evans, D. Gareth; Lalloo, Fiona; Jacobs, Chris; Eeles, Ros; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana; Cole, Trevor; Cook, Jackie; Paterson, Joan; Douglas, Fiona; Brewer, Carole; Hodgson, Shirley; Morrison, Patrick J.; Walker, Lisa; Porteous, Mary E.; Kennedy, M. John; Pathak, Harsh; Godwin, Andrew K.; Stoppa-Lyonnet, Dominique; Caux-Moncoutier, Virginie; de Pauw, Antoine; Gauthier-Villars, Marion; Mazoyer, Sylvie; Léoné, Mélanie; Calender, Alain; Lasset, Christine; Bonadona, Valérie; Hardouin, Agnès; Berthet, Pascaline; Bignon, Yves-Jean; Uhrhammer, Nancy; Faivre, Laurence; Loustalot, Catherine; Buys, Saundra; Daly, Mary; Miron, Alex; Terry, Mary Beth; Chung, Wendy K.; John, Esther M.; Southey, Melissa; Goldgar, David; Singer, Christian F.; tea, Muy-Kheng; Pfeiler, Georg; Fink-Retter, Anneliese; Hansen, Thomas v O.; Ejlertsen, Bent; Johannsson, Oskar Th; Offit, Kenneth; Kirchhoff, Tomas; Gaudet, Mia M.; Vijai, Joseph; Robson, Mark; Piedmonte, Marion; Phillips, Kelly-Anne; van Le, Linda; Hoffman, James S.; Ewart Toland, Amanda; Montagna, Marco; Tognazzo, Silvia; Imyanitov, Evgeny; Issacs, Claudine; Janavicius, Ramunas; Lazaro, Conxi; Blanco, Iganacio; Tornero, Eva; Navarro, Matilde; Moysich, Kirsten B.; Karlan, Beth Y.; Gross, Jenny; Olah, Edith; Vaszko, Tibor; teo, Soo-Hwang; Ganz, Patricia A.; Beattie, Mary S.; Dorfling, Cecelia M.; van Rensburg, Elizabeth J.; Diez, Orland; Kwong, Ava; Schmutzler, Rita K.; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Heidemann, Simone; Niederacher, Dieter; Preisler-Adams, Sabine; Gadzicki, Dorotehea; Varon-Mateeva, Raymonda; Deissler, Helmut; Gehrig, Andrea; Sutter, Christian; Kast, Karin; Fiebig, Britta; Schäfer, Dieter; Caldes, Trinidad; de la Hoya, Miguel; Nevanlinna, Heli; Aittomäki, Kristiina; Plante, Marie; Spurdle, Amanda B.; Neuhausen, Susan L.; Ding, Yuan Chun; Wang, Xianshu; Lindor, Noralane; Fredericksen, Zachary; Pankratz, V. Shane; Peterlongo, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Bonanni, Bernardo; Bernard, Loris; Dolcetti, Riccardo; Papi, Laura; Ottini, Laura; Radice, Paolo; Greene, Mark H.; Mai, Phuong L.; Andrulis, Irene L.; Glendon, Gord; Ozcelik, Hilmi; Pharoah, Paul D. P.; Gayther, Simon A.; Simard, Jacques; Easton, Douglas F.; Couch, Fergus J.; Chenevix-Trench, Georgia; Miedzybrodzka, Zosia; Gregory, Helen; Morrison, Patrick; Jeffers, Lisa; Ong, Kai-Ren; Hoffman, Jonathan; Donaldson, Alan; James, Margaret; Downing, Sarah; Taylor, Amy; Murray, Alexandra; Rogers, Mark T.; McCann, Emma; Barton, David; Porteous, Mary; Drummond, Sarah; Kivuva, Emma; Searle, Anne; Goodman, Selina; Hill, Kathryn; Murday, Victoria; Bradshaw, Nicola; Snadden, Lesley; Longmuir, Mark; Watt, Catherine; Gibson, Sarah; Haque, Eshika; Tobias, Ed; Duncan, Alexis; Izatt, Louise; Langman, Caroline; Whaite, Anna; Dorkins, Huw; Barwell, Julian; Serra-Feliu, Gemma; Ellis, Ian; Houghton, Catherine; Taylor, Jane; Side, Lucy; Male, Alison; Berlin, Cheryl; Eason, Jacqueline; Collier, Rebecca; Claber, Oonagh; Jobson, Irene; McLeod, Diane; Halliday, Dorothy; Durell, Sarah; Stayner, Barbara; Shanley, Susan; Rahman, Nazneen; Houlston, Richard; Bancroft, Elizabeth; D'Mello, Lucia; Page, Elizabeth; Ardern-Jones, Audrey; Kohut, Kelly; Wiggins, Jennifer; Castro, Elena; Mitra, Anita; Robertson, Lisa; Quarrell, Oliver; Bardsley, Cathryn; Goff, Sheila; Brice, Glen; Winchester, Lizzie; Eddy, Charlotte; Tripathi, Vishakha; Attard, Virginia; Lucassen, Anneke; Crawford, Gillian; McBride, Donna; Smalley, Sarah; Sinilnikova, Olga; Barjhoux, Laure; Verny-Pierre, Carole; Giraud, Sophie; Léone, Mélanie; Buecher, Bruno; Houdayer, Claude; Moncoutier, Virginie; Belotti, Muriel; Tirapo, Carole; Bressac-de-Paillerets, Brigitte; Remenieras, Audrey; Byrede, Véronique; Caron, Olivier; Lenoir, Gilbert; Urhammer, Nancy; Sobol, Hagay; Bourdon, Violaine; Noguchi, Tetsuro; Eisinger, François; Coulet, Florence; Colas, Chrystelle; Soubrier, Florent; Coupier, Isabelle; Pujol, Pascal; Peyrat, Jean-Philippe; Fournier, Joëlle; Révilliion, Françoise; Vennin, Philippe; Adenis, Claude; Rouleau, Etienne; Lidereau, Rosette; Demange, Liliane; Nogues, Catherine; Muller, Danièle; Fricker, Jean-Pierre; Barouk-Simonet, Emmanuelle; Bonnet, Françoise; Bubien, Virginie; Sevenet, Nicolas; Longy, Michel; Toulas, Christine; Guimbaud, Rosine; Gladieff, Laurence; Feillel, Viviane; Leroux, Dominique; Dreyfus, Hélène; Rebischung, Christine; Peysselon, Megalie; Coron, Fanny; Prieur, Fabienne; Lebrun, Marine; Kientz, Caroline; Frénay, Marc; Vénat-Bouvet, Laurence; Delnatte, Capucine; Mortemousque, Isabelle; Lynch, Henry T.; Snyder, Carrie L.; Hogervorst, F. B. L.; Verhoef, S.; Verheus, M.; van't Veer, L. J.; van Leeuwen, F. E.; Collée, M.; van den Ouweland, A. M. W.; Jager, A.; Hooning, M. J.; Tilanus-Linthorst, M. M. A.; Seynaeve, C.; van Asperen, C. J.; Wijnen, J. T.; Vreeswijk, M. P.; Tollenaar, R. A.; Devilee, P.; Ligtenberg, M. J.; Hoogerbrugge, N.; Ausems, M. G.; van der Luijt, R. B.; van Os, T. A.; Gille, J. J. P.; Waisfisz, Q.; Gomez-Garcia, E. B.; van Roozendaal, C. E.; Blok, Marinus J.; Caanen, B.; Oosterwijk, J. C.; van der Hout, A. H.; Mourits, M. J.; Vasen, H. F.; Thorne, Heather; Niedermayr, Eveline; Gill, Mona; Collins, Lucine; Gokgoz, Nalan; Selander, Teresa; Weerasooriya, Nayana; Karlsson, Per; Nordlilng, Margareta; Bergman, Annika; Einbeigi, Zakaria; Liedgren, Sigrun; Borg, Åke; Loman, Niklas; Soller, Maria; Jernström, Helena; Harbst, Katja; Henriksson, Karin; Arver, Brita; von Wachenfeldt, Anna; Barbany-Bustinza, Gisela; Rantala, Johanna; Grönberg, Henrik; Stattin, Eva-Lena; Emanuelsson, Monica; Ehrencrona, Hans; Rosenquist, Richard; Dahl, Niklas

    2012-01-01

    Germline mutations in BRCA1 and BRCA2 are associated with increased risks of breast and ovarian cancer. A genome-wide association study (GWAS) identified six alleles associated with risk of ovarian cancer for women in the general population. We evaluated four of these loci as potential modifiers of

  8. A survey of new temperature-sensitive, embryonic-lethal mutations in C. elegans: 24 alleles of thirteen genes.

    Directory of Open Access Journals (Sweden)

    Sean M O'Rourke

    2011-03-01

    Full Text Available To study essential maternal gene requirements in the early C. elegans embryo, we have screened for temperature-sensitive, embryonic lethal mutations in an effort to bypass essential zygotic requirements for such genes during larval and adult germline development. With conditional alleles, multiple essential requirements can be examined by shifting at different times from the permissive temperature of 15°C to the restrictive temperature of 26°C. Here we describe 24 conditional mutations that affect 13 different loci and report the identity of the gene mutations responsible for the conditional lethality in 22 of the mutants. All but four are mis-sense mutations, with two mutations affecting splice sites, another creating an in-frame deletion, and one creating a premature stop codon. Almost all of the mis-sense mutations affect residues conserved in orthologs, and thus may be useful for engineering conditional mutations in other organisms. We find that 62% of the mutants display additional phenotypes when shifted to the restrictive temperature as L1 larvae, in addition to causing embryonic lethality after L4 upshifts. Remarkably, we also found that 13 out of the 24 mutations appear to be fast-acting, making them particularly useful for careful dissection of multiple essential requirements. Our findings highlight the value of C. elegans for identifying useful temperature-sensitive mutations in essential genes, and provide new insights into the requirements for some of the affected loci.

  9. Efficient Identification of Causal Mutations through Sequencing of Bulked F2 from Two Allelic Bloomless Mutants of Sorghum bicolor

    Directory of Open Access Journals (Sweden)

    Yinping Jiao

    2018-01-01

    Full Text Available Sorghum (Sorghum bicolor Moench, L. plant accumulates copious layers of epi-cuticular wax (EW on its aerial surfaces, to a greater extent than most other crops. EW provides a vapor barrier that reduces water loss, and is therefore considered to be a major determinant of sorghum's drought tolerance. However, little is known about the genes responsible for wax accumulation in sorghum. We isolated two allelic mutants, bloomless40-1 (bm40-1 and bm40-2, from a mutant library constructed from ethyl methane sulfonate (EMS treated seeds of an inbred, BTx623. Both mutants were nearly devoid of the EW layer. Each bm mutant was crossed to the un-mutated BTx623 to generated F2 populations that segregated for the bm phenotype. Genomic DNA from 20 bm F2 plants from each population was bulked for whole genome sequencing. A single gene, Sobic.001G228100, encoding a GDSL-like lipase/acylhydrolase, had unique homozygous mutations in each bulked F2 population. Mutant bm40-1 harbored a missense mutation in the gene, whereas bm40-2 had a splice donor site mutation. Our findings thus provide strong evidence that mutation in this GDSL-like lipase gene causes the bm phenotype, and further demonstrate that this approach of sequencing two independent allelic mutant populations is an efficient method for identifying causal mutations. Combined with allelic mutants, MutMap provides powerful method to identify all causal genes for the large collection of bm mutants in sorghum, which will provide insight into how sorghum plants accumulate such abundant EW on their aerial surface. This knowledge may facilitate the development of tools for engineering drought-tolerant crops with reduced water loss.

  10. Detection of CALR and MPL Mutations in Low Allelic Burden JAK2 V617F Essential Thrombocythemia.

    Science.gov (United States)

    Usseglio, Fabrice; Beaufils, Nathalie; Calleja, Anne; Raynaud, Sophie; Gabert, Jean

    2017-01-01

    Myeloproliferative neoplasms are clonal hematopoietic stem cell disorders characterized by aberrant proliferation and an increased tendency toward leukemic transformation. The genes JAK2, MPL, and CALR are frequently altered in these syndromes, and their mutations are often a strong argument for diagnosis. We analyzed the mutational profiles of these three genes in a cohort of 164 suspected myeloproliferative neoplasms. JAK2 V617F mutation was detected by real-time PCR, whereas high-resolution melting analysis followed by Sanger sequencing were used for searching for mutations in JAK2 exon 12, CALR, and MPL. JAK2 V617F mutation was associated with CALR (n = 4) and MPL (n = 4) mutations in 8 of 103 essential thrombocytosis patients. These cases were harboring a JAK2 V617F allelic burden of MPL genes in myeloproliferative neoplasms and suggest that CALR and MPL should be analyzed not only in JAK2-negative patients but also in low V617F mutation patients. Follow-up of these double-mutation cases will be important for determining whether this group of patients presents particular evolution or complications. Copyright © 2017 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  11. Mosaicism in segmental darier disease: an in-depth molecular analysis quantifying proportions of mutated alleles in various tissues

    DEFF Research Database (Denmark)

    Harboe, Theresa Larriba; Willems, Patrick; Jespersgaard, Cathrine

    2011-01-01

    Darier disease is an autosomal dominant genodermatosis caused by germline mutations in the ATP2A2 gene. Clinical expression is variable, including rare segmental phenotypes thought to be caused by postzygotic mosaicism. Genetic counseling of segmental Darier patients is complex, as risk of transm......Darier disease is an autosomal dominant genodermatosis caused by germline mutations in the ATP2A2 gene. Clinical expression is variable, including rare segmental phenotypes thought to be caused by postzygotic mosaicism. Genetic counseling of segmental Darier patients is complex, as risk...... of transmitting a nonsegmental phenotype to offspring is of unknown magnitude. We present the first in-depth molecular analysis of a mosaic patient with segmental disease, quantifying proportions of mutated and normal alleles in various tissues. Pyrosequence analysis of DNA from semen, affected and normal skin......, peripheral leukocytes and hair revealed an uneven distribution of the mutated allele, from 14% in semen to 37% in affected skin. We suggest a model for segmental manifestation expression where a threshold number of mutated cells is needed for manifestation development. We further recommend molecular analysis...

  12. Unexpected allelic heterogeneity and spectrum of mutations in Fowler syndrome revealed by next-generation exome sequencing.

    Science.gov (United States)

    Lalonde, Emilie; Albrecht, Steffen; Ha, Kevin C H; Jacob, Karine; Bolduc, Nathalie; Polychronakos, Constantin; Dechelotte, Pierre; Majewski, Jacek; Jabado, Nada

    2010-08-01

    Protein coding genes constitute approximately 1% of the human genome but harbor 85% of the mutations with large effects on disease-related traits. Therefore, efficient strategies for selectively sequencing complete coding regions (i.e., "whole exome") have the potential to contribute our understanding of human diseases. We used a method for whole-exome sequencing coupling Agilent whole-exome capture to the Illumina DNA-sequencing platform, and investigated two unrelated fetuses from nonconsanguineous families with Fowler Syndrome (FS), a stereotyped phenotype lethal disease. We report novel germline mutations in feline leukemia virus subgroup C cellular-receptor-family member 2, FLVCR2, which has recently been shown to cause FS. Using this technology, we identified three types of genetic abnormalities: point-mutations, insertions-deletions, and intronic splice-site changes (first pathogenic report using this technology), in the fetuses who both were compound heterozygotes for the disease. Although revealing a high level of allelic heterogeneity and mutational spectrum in FS, this study further illustrates the successful application of whole-exome sequencing to uncover genetic defects in rare Mendelian disorders. Of importance, we show that we can identify genes underlying rare, monogenic and recessive diseases using a limited number of patients (n=2), in the absence of shared genetic heritage and in the presence of allelic heterogeneity.

  13. Association of breast cancer risk in BRCA1 and BRCA2 mutation carriers with genetic variants showing differential allelic expression

    DEFF Research Database (Denmark)

    Hamdi, Yosr; Soucy, Penny; Kuchenbaeker, Karoline B

    2017-01-01

    and ovarian cancer risks in 15,252 BRCA1 and 8211 BRCA2 mutation carriers ascertained from 54 studies participating in the Consortium of Investigators of Modifiers of BRCA1/2. RESULTS: We identified a region on 11q22.3 that is significantly associated with breast cancer risk in BRCA1 mutation carriers (most...... studies using estrogen receptor (ER)-negative or triple-negative (i.e., ER-, progesterone receptor-, and HER2-negative) cases could therefore be helpful to confirm the association of this locus with breast cancer risk.......1 and BRCA2 mutation carriers, a list of 175 genes was developed based of their involvement in cancer-related pathways. METHODS: Using data from a genome-wide map of SNPs associated with allelic expression, we assessed the association of ~320 SNPs located in the vicinity of these genes with breast...

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

    Science.gov (United States)

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

    2017-10-01

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

  15. HRAS mutations in Costello syndrome: detection of constitutional activating mutations in codon 12 and 13 and loss of wild-type allele in malignancy.

    Science.gov (United States)

    Estep, Anne L; Tidyman, William E; Teitell, Michael A; Cotter, Philip D; Rauen, Katherine A

    2006-01-01

    Costello syndrome (CS) is a complex developmental disorder involving characteristic craniofacial features, failure to thrive, developmental delay, cardiac and skeletal anomalies, and a predisposition to develop neoplasia. Based on similarities with other cancer syndromes, we previously hypothesized that CS is likely due to activation of signal transduction through the Ras/MAPK pathway [Tartaglia et al., 2003]. In this study, the HRAS coding region was sequenced for mutations in a large, well-characterized cohort of 36 CS patients. Heterogeneous missense point mutations predicting an amino acid substitution were identified in 33/36 (92%) patients. The majority (91%) had a 34G --> A transition in codon 12. Less frequent mutations included 35G --> C (codon 12) and 37G --> T (codon 13). Parental samples did not have an HRAS mutation supporting the hypothesis of de novo heterogeneous mutations. There is phenotypic variability among patients with a 34G --> A transition. The most consistent features included characteristic facies and skin, failure to thrive, developmental delay, musculoskeletal abnormalities, visual impairment, cardiac abnormalities, and generalized hyperpigmentation. The two patients with 35G --> C had cardiac arrhythmias whereas one patient with a 37G --> T transversion had an enlarged aortic root. Of the patients with a clinical diagnosis of CS, neoplasia was the most consistent phenotypic feature for predicating an HRAS mutation. To gain an understanding of the relationship between constitutional HRAS mutations and malignancy, HRAS was sequenced in an advanced biphasic rhabdomyosarcoma/fibrosarcoma from an individual with a 34G --> A mutation. Loss of the wild-type HRAS allele was observed, suggesting tumorigenesis in CS patients is accompanied by additional somatic changes affecting HRAS. Finally, due to phenotypic overlap between CS and cardio-facio-cutaneous (CFC) syndromes, the HRAS coding region was sequenced in a well-characterized CFC cohort

  16. Computational Simulation and Analysis of Mutations: Nucleotide Fixation, Allelic Age and Rare Genetic Variations in Population

    Science.gov (United States)

    Qiu, Shuhao

    2015-01-01

    In order to investigate the complexity of mutations, a computational approach named Genome Evolution by Matrix Algorithms ("GEMA") has been implemented. GEMA models genomic changes, taking into account hundreds of mutations within each individual in a population. By modeling of entire human chromosomes, GEMA precisely mimics real…

  17. Polymorphism of the cytochrome P450 CYP2D6 gene in a European population: characterization of 48 mutations and 53 alleles, their frequencies and evolution.

    Science.gov (United States)

    Marez, D; Legrand, M; Sabbagh, N; Lo Guidice, J M; Spire, C; Lafitte, J J; Meyer, U A; Broly, F

    1997-06-01

    The polymorphic cytochrome P450 CYP2D6 is involved in the metabolism of various drugs of wide therapeutic use and is a presumed susceptibility factor for certain environmentally-induced diseases. Our aim was to define the mutations and alleles of the CYP2D6 gene and to evaluate their frequencies in the European population. Using polymerase chain reaction-single strand conformation polymorphism analysis, 672 unrelated subjects were screened for mutations in the 9 exons of the gene and their exon-intron boundaries. A total of 48 point mutations were identified, of which 29 were novel. Mutations 1749 G-->C, 2938 C-->T and 4268 G-->C represented 52.6%, 34.3% and 52.9% of the mutations in the total population, respectively. Of the eight detrimental mutations detected, the 1934 G-->A, the 1795 Tdel and the 2637 Adel accounted for 65.8%, 6.2% and 4.8% respectively, within the poor metabolizer subgroup. Fifty-three different alleles were characterized from the mutation pattern and by allele-specific sequencing. They are derived from three major alleles, namely the wild-type CYP2D6*1A, the functional CYP2D6*2 and the null CYP2D6*4A. Five allelic variants (CYP2D6*1A, *2, *2B, *4A and *5) account for about 87% of all alleles, while the remaining alleles occur with a frequency of 0.1%-2.7%. These data provide a solid basis for future epidemiological, clinical as well as interethnic studies of the CYP2D6 polymorphism and highlight that the described single strand conformation polymorphism method can be successfully used in designing such studies.

  18. Increased frequency of co-existing JAK2 exon-12 or MPL exon-10 mutations in patients with low JAK2(V617F) allelic burden.

    Science.gov (United States)

    Nussenzveig, Roberto H; Pham, Ha T; Perkins, Sherrie L; Prchal, Josef T; Agarwal, Archana M; Salama, Mohamed E

    2016-01-01

    The frequency of co-existing JAK2(V617F)/MPL and JAK2(V617F)/JAK2 exon-12 mutations has not been previously investigated in MPNs. Poor survival was reported in primary myelofibrosis with low JAK2(V617F) allelic burden. However, mutational status of JAK2 exon-12 or MPL were not reported in these patients. This study developed a cost-effective multiplex high resolution melt assay that screens for mutations in JAK2 gene exons-12 and -14 ((V617F)) and MPL gene exon-10. Co-existing mutations with JAK2(V617F) were detected in 2.9% (6/208; two JAK2 exon-12 and four MPL exon-10) patient specimens with known JAK2(V617F) (allelic-burden range: 0.1-96.8%). Co-existing mutations were detected in specimens with MPL exon-10 mutation should be pursued.

  19. Allelic hierarchy of CDH23 mutations causing non-syndromic deafness DFNB12 or Usher syndrome USH1D in compound heterozygotes.

    Science.gov (United States)

    Schultz, Julie M; Bhatti, Rashid; Madeo, Anne C; Turriff, Amy; Muskett, Julie A; Zalewski, Christopher K; King, Kelly A; Ahmed, Zubair M; Riazuddin, Saima; Ahmad, Nazir; Hussain, Zawar; Qasim, Muhammad; Kahn, Shaheen N; Meltzer, Meira R; Liu, Xue Z; Munisamy, Murali; Ghosh, Manju; Rehm, Heidi L; Tsilou, Ekaterini T; Griffith, Andrew J; Zein, Wadih M; Brewer, Carmen C; Riazuddin, Sheikh; Friedman, Thomas B

    2011-11-01

    Recessive mutant alleles of MYO7A, USH1C, CDH23, and PCDH15 cause non-syndromic deafness or type 1 Usher syndrome (USH1) characterised by deafness, vestibular areflexia, and vision loss due to retinitis pigmentosa. For CDH23, encoding cadherin 23, non-syndromic DFNB12 deafness is associated primarily with missense mutations hypothesised to have residual function. In contrast, homozygous nonsense, frame shift, splice site, and some missense mutations of CDH23, all of which are presumably functional null alleles, cause USH1D. The phenotype of a CDH23 compound heterozygote for a DFNB12 allele in trans configuration to an USH1D allele is not known and cannot be predicted from current understanding of cadherin 23 function in the retina and vestibular labyrinth. To address this issue, this study sought CDH23 compound heterozygotes by sequencing this gene in USH1 probands, and families segregating USH1D or DFNB12. Five non-syndromic deaf individuals were identified with normal retinal and vestibular phenotypes that segregate compound heterozygous mutations of CDH23, where one mutation is a known or predicted USH1 allele. One DFNB12 allele in trans configuration to an USH1D allele of CDH23 preserves vision and balance in deaf individuals, indicating that the DFNB12 allele is phenotypically dominant to an USH1D allele. This finding has implications for genetic counselling and the development of therapies for retinitis pigmentosa in Usher syndrome. ACCESSION NUMBERS: The cDNA and protein Genbank accession numbers for CDH23 and cadherin 23 used in this paper are AY010111.2 and AAG27034.2, respectively.

  20. Association of breast cancer risk in BRCA1 and BRCA2 mutation carriers with genetic variants showing differential allelic expression

    DEFF Research Database (Denmark)

    Hamdi, Yosr; Soucy, Penny; Kuchenbaeker, Karoline B

    2017-01-01

    1 and BRCA2 mutation carriers, a list of 175 genes was developed based of their involvement in cancer-related pathways. METHODS: Using data from a genome-wide map of SNPs associated with allelic expression, we assessed the association of ~320 SNPs located in the vicinity of these genes with breast...... and ovarian cancer risks in 15,252 BRCA1 and 8211 BRCA2 mutation carriers ascertained from 54 studies participating in the Consortium of Investigators of Modifiers of BRCA1/2. RESULTS: We identified a region on 11q22.3 that is significantly associated with breast cancer risk in BRCA1 mutation carriers (most...... significant SNP rs228595 p = 7 × 10(-6)). This association was absent in BRCA2 carriers (p = 0.57). The 11q22.3 region notably encompasses genes such as ACAT1, NPAT, and ATM. Expression quantitative trait loci associations were observed in both normal breast and tumors across this region, namely for ACAT1...

  1. Ovarian Cancer Susceptibility Alleles and Risk of Ovarian Cancer in BRCA1 and BRCA2 Mutation Carriers

    Science.gov (United States)

    Ramus, Susan J.; Antoniou, Antonis C; Kuchenbaecker, Karoline B.; Soucy, Penny; Beesley, Jonathan; Chen, Xiaoqing; McGuffog, Lesley; Sinilnikova, Olga M.; Healey, Sue; Barrowdale, Daniel; Lee, Andrew; Thomassen, Mads; Gerdes, Anne-Marie; Kruse, Torben A.; Jensen, Uffe Birk; Skytte, Anne-Bine; Caligo, Maria A.; Liljegren, Annelie; Lindblom, Annika; Olsson, Håkan; Kristoffersson, Ulf; Stenmark-Askmalm, Marie; Melin, Beatrice; Domchek, Susan M.; Nathanson, Katherine L.; Rebbeck, Timothy R.; Jakubowska, Anna; Lubinski, Jan; Jaworska, Katarzyna; Durda, Katarzyna; Złowocka, Elżbieta; Gronwald, Jacek; Huzarski, Tomasz; Byrski, Tomasz; Cybulski, Cezary; Toloczko-Grabarek, Aleksandra; Osorio, Ana; Benitez, Javier; Duran, Mercedes; Tejada, Maria-Isabel; Hamann, Ute; Rookus, Matti; van Leeuwen, Flora E.; Aalfs, Cora M.; Meijers-Heijboer, Hanne E.J.; van Asperen, Christi J.; van Roozendaal, K.E.P.; Hoogerbrugge, Nicoline; Collée, J. Margriet; Kriege, Mieke; van der Luijt, Rob B.; Peock, Susan; Frost, Debra; Ellis, Steve D.; Platte, Radka; Fineberg, Elena; Evans, D. Gareth; Lalloo, Fiona; Jacobs, Chris; Eeles, Ros; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana; Cole, Trevor; Cook, Jackie; Paterson, Joan; Douglas, Fiona; Brewer, Carole; Hodgson, Shirley; Morrison, Patrick J.; Walker, Lisa; Porteous, Mary E.; Kennedy, M. John; Pathak, Harsh; Godwin, Andrew K.; Stoppa-Lyonnet, Dominique; Caux-Moncoutier, Virginie; de Pauw, Antoine; Gauthier-Villars, Marion; Mazoyer, Sylvie; Léoné, Mélanie; Calender, Alain; Lasset, Christine; Bonadona, Valérie; Hardouin, Agnès; Berthet, Pascaline; Bignon, Yves-Jean; Uhrhammer, Nancy; Faivre, Laurence; Loustalot, Catherine; Buys, Saundra; Daly, Mary; Miron, Alex; Terry, Mary Beth; Chung, Wendy K.; John, Esther M; Southey, Melissa; Goldgar, David; Singer, Christian F; Tea, Muy-Kheng; Pfeiler, Georg; Fink-Retter, Anneliese; Hansen, Thomas v. O.; Ejlertsen, Bent; Johannsson, Oskar Th.; Offit, Kenneth; Kirchhoff, Tomas; Gaudet, Mia M.; Vijai, Joseph; Robson, Mark; Piedmonte, Marion; Phillips, Kelly-Anne; Van Le, Linda; Hoffman, James S; Toland, Amanda Ewart; Montagna, Marco; Tognazzo, Silvia; Imyanitov, Evgeny; Isaacs, Claudine; Janavicius, Ramunas; Lazaro, Conxi; Blanco, Ignacio; Tornero, Eva; Navarro, Matilde; Moysich, Kirsten B.; Karlan, Beth Y.; Gross, Jenny; Olah, Edith; Vaszko, Tibor; Teo, Soo-Hwang; Ganz, Patricia A.; Beattie, Mary S.; Dorfling, Cecelia M; van Rensburg, Elizabeth J; Diez, Orland; Kwong, Ava; Schmutzler, Rita K.; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Heidemann, Simone; Niederacher, Dieter; Preisler-Adams, Sabine; Gadzicki, Dorotehea; Varon-Mateeva, Raymonda; Deissler, Helmut; Gehrig, Andrea; Sutter, Christian; Kast, Karin; Fiebig, Britta; Schäfer, Dieter; Caldes, Trinidad; de la Hoya, Miguel; Nevanlinna, Heli; Aittomäki, Kristiina; Plante, Marie; Spurdle, Amanda B.; Neuhausen, Susan L.; Ding, Yuan Chun; Wang, Xianshu; Lindor, Noralane; Fredericksen, Zachary; Pankratz, V. Shane; Peterlongo, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Bonanni, Bernardo; Bernard, Loris; Dolcetti, Riccardo; Papi, Laura; Ottini, Laura; Radice, Paolo; Greene, Mark H.; Mai, Phuong L.; Andrulis, Irene L.; Glendon, Gord; Ozcelik, Hilmi; Pharoah, Paul D.P.; Gayther, Simon A.; Simard, Jacques; Easton, Douglas F.; Couch, Fergus J.; Chenevix-Trench, Georgia

    2012-01-01

    Germline mutations in BRCA1 and BRCA2 are associated with increased risks of breast and ovarian cancer. A genome-wide association study (GWAS) identified six alleles associated with risk of ovarian cancer for women in the general population. We evaluated four of these loci as potential modifiers of ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. Four single-nucleotide polymorphisms (SNPs), rs10088218 (at 8q24), rs2665390 (at 3q25), rs717852 (at 2q31), and rs9303542 (at 17q21), were genotyped in 12,599 BRCA1 and 7,132 BRCA2 carriers, including 2,678 ovarian cancer cases. Associations were evaluated within a retrospective cohort approach. All four loci were associated with ovarian cancer risk in BRCA2 carriers; rs10088218 per-allele hazard ratio (HR) = 0.81 (95% CI: 0.67–0.98) P-trend = 0.033, rs2665390 HR = 1.48 (95% CI: 1.21–1.83) P-trend = 1.8 × 10−4, rs717852 HR = 1.25 (95% CI: 1.10–1.42) P-trend = 6.6 × 10−4, rs9303542 HR = 1.16 (95% CI: 1.02–1.33) P-trend = 0.026. Two loci were associated with ovarian cancer risk in BRCA1 carriers; rs10088218 per-allele HR = 0.89 (95% CI: 0.81–0.99) P-trend = 0.029, rs2665390 HR = 1.25 (95% CI: 1.10–1.42) P-trend = 6.1 × 10−4. The HR estimates for the remaining loci were consistent with odds ratio estimates for the general population. The identification of multiple loci modifying ovarian cancer risk may be useful for counseling women with BRCA1 and BRCA2 mutations regarding their risk of ovarian cancer. PMID:22253144

  2. Nonsyndromic recessive deafness DFNB18 and Usher syndrome type IC are allelic mutations of USHIC.

    Science.gov (United States)

    Ahmed, Zubair M; Smith, Tenesha N; Riazuddin, Saima; Makishima, Tomoko; Ghosh, Manju; Bokhari, Sirosh; Menon, Puthezhath S N; Deshmukh, Dilip; Griffith, Andrew J; Riazuddin, Sheikh; Friedman, Thomas B; Wilcox, Edward R

    2002-06-01

    Human chromosome 11 harbors two Usher type I loci, USHIB and USHIC, which encode myosin VIIA and harmonin, respectively. The USHIC locus overlaps the reported critical interval for nonsyndromic deafness locus DFNB18. We found an IVS12+5G-->C mutation in the USHIC gene, which is associated with nonsyndromic recessive deafness ( DFNB18) segregating in the original family, S-11/12. No other disease-associated mutation was found in the other 27 exons or in the intron-exon boundaries, and the IVS12+5G-->C mutation was not present in 200 representative unaffected individuals ascertained from the same area of India. An exon-trapping assay with a construct harboring IVS12+5G-->C generated wildtype spliced mRNA having exons 11 and 12 and mRNA that skipped exon 12. We conclude that mutations of USHIC can cause both Usher syndrome type IC and nonsyndromic recessive deafness DFNB18.

  3. Associations of common breast cancer susceptibility alleles with risk of breast cancer subtypes in BRCA1 and BRCA2 mutation carriers

    OpenAIRE

    Andrulis, IL; Mulligan, AM; Schmutzler, RK; Barrowdale, D; McGuffog, L; Robson, M; Schmidt, MK; Spurdle, AB; Neuhausen, SL; Kuchenbaecker, KB

    2014-01-01

    Introduction: More than 70 common alleles are known to be involved in breast cancer (BC) susceptibility and several exhibit significant heterogeneity in their associations with different BC subtypes. Although there are differences in the association patterns between BRCA1 and BRCA2 mutation carriers and the general population for several loci, no study has comprehensively evaluated the associations of all known BC susceptibility alleles with risk of BC subtypes in BRCA1 and BRC...

  4. Suppression of the Escherichia coli ssb-1 mutation by an allele of groEL.

    OpenAIRE

    Ruben, S M; VanDenBrink-Webb, S E; Rein, D C; Meyer, R R

    1988-01-01

    A series of spontaneous suppressors to the temperature-sensitive phenotype of the single-stranded DNA-binding protein mutation ssb-1 were isolated. A genomic library of EcoRI fragments from one of these suppressor strains was prepared by using pBR325 as the cloning vector. A 10.0-kilobase class of inserts was identified as carrying the ssb-1 gene itself. A second class of 8.3-kilobase inserts was shown to contain the groE region by (i) restriction analysis, (ii) Southern hybridization of the ...

  5. Prognostic significance of ASXL1, JAK2V617F mutations and JAK2V617F allele burden in Philadelphia-negative myeloproliferative neoplasms

    Directory of Open Access Journals (Sweden)

    Yonal-Hindilerden I

    2015-06-01

    Full Text Available Ipek Yonal-Hindilerden, Aynur Daglar-Aday, Basak Akadam-Teker, Ceylan Yilmaz, Meliha Nalcaci, Akif Selim Yavuz, Deniz SarginDivision of Hematology, Department of Internal Medicine, Istanbul Medical Faculty, Istanbul University, Fatih-Istanbul, Turkey Background: Despite insights into the genetic basis of Philadelphia-negative myeloproliferative neoplasms (Ph-negative MPNs, a significant proportion of essential thrombocythemia (ET and primary myelofibrosis (PMF patients present with no known MPN disease alleles. There were no previous studies investigating the impact of ASXL1 mutations in Ph-negative MPNs in Turkey. In the current study, we investigated the prognostic significance of ASXL1 mutations in Turkish MPN patients. We also aimed to determine the prognostic significance of JAK2V617F allele burden and the relationship of JAK2V617F mutation with ASXL1 mutations in Ph-negative MPNs. Methods: About 184 patients from a single center diagnosed with Ph-negative MPNs were screened for ASXL1, JAK2V617F mutations, and JAK2V617F allele burden: 107 ET and 77 PMF. Results: A total of 29 ASXL1 mutations were detected in 24.7% of PMF and 8.4% of ET patients. ASXL1-mutated ET patients showed a trend toward an increase in the incidence of cerebrovascular events and higher total leukocyte counts. ASXL1-mutation in PMF was associated with older age and a higher prevalence of bleeding complications. In univariate analysis, overall survival (OS was significantly reduced in ASXL1-mutated PMF patients. In multivariate analysis, Dynamic International Prognostic Scoring System-plus high-risk category and ASXL1 mutation status were independently associated with shorter survival in PMF. In PMF, mutational status and allele burden of JAK2V617F showed no difference in terms of OS and leukemia-free survival. Conclusion: We conclude that ASXL1 mutations are molecular predictors of short OS in PMF. Keywords: Philadelphia-negative myeloproliferative neoplasms (Ph

  6. Allelic heterogeneity and genetic modifier loci contribute to clinical variation in males with X-linked retinitis pigmentosa due to RPGR mutations.

    Directory of Open Access Journals (Sweden)

    Abigail T Fahim

    Full Text Available Mutations in RPGR account for over 70% of X-linked retinitis pigmentosa (XlRP, characterized by retinal degeneration and eventual blindness. The clinical consequences of RPGR mutations are highly varied, even among individuals with the same mutation: males demonstrate a wide range of clinical severity, and female carriers may or may not be affected. This study describes the phenotypic diversity in a cohort of 98 affected males from 56 families with RPGR mutations, and demonstrates the contribution of genetic factors (i.e., allelic heterogeneity and genetic modifiers to this diversity. Patients were categorized as grade 1 (mild, 2 (moderate or 3 (severe according to specific clinical criteria. Patient DNAs were genotyped for coding SNPs in 4 candidate modifier genes with products known to interact with RPGR protein: RPGRIP1, RPGRIP1L, CEP290, and IQCB1. Family-based association testing was performed using PLINK. A wide range of clinical severity was observed both between and within families. Patients with mutations in exons 1-14 were more severely affected than those with ORF15 mutations, and patients with predicted null alleles were more severely affected than those predicted to make RPGR protein. Two SNPs showed association with severe disease: the minor allele (N of I393N in IQCB1 (p = 0.044 and the common allele (R of R744Q in RPGRIP1L (p = 0.049. These data demonstrate that allelic heterogeneity contributes to phenotypic diversity in XlRP and suggest that this may depend on the presence or absence of RPGR protein. In addition, common variants in 2 proteins known to interact with RPGR are associated with severe disease in this cohort.

  7. Identification of novel splice site mutation IVS9 + 1(G > A) and novel complex allele G355R/R359X in Type 1 Gaucher patients heterozygous for mutation N370S.

    Science.gov (United States)

    Hoitsema, Kourtnee; Amato, Dominick; Khan, Aneal; Sirrs, Sandra; Choy, Francis Y M

    2016-09-01

    Gaucher disease is an autosomal recessive lysosomal storage disorder resulting from deficient glucocerebrosidase activity. More than 350 mutations that cause Gaucher disease have been described to date. Novel mutations can potentially provide insight into the glucocerebrosidase structure-function relationship and biochemical basis of the disease. Here, we report the identification of two novel mutations in two unrelated patients with type I (non-neuronopathic) Gaucher disease: 1) a splice site mutation IVS9 + 1G > A; and (2) a complex allele (cis) G355R/R359X. Both patients have a common N370S mutation in the other allele. The splice site mutation results from an intronic base substitution (G to A, c.1328 + 1, g.5005) at the donor splice site of exon and intron 9. The complex allele results from two point mutations in exon 8 of glucocerebrosidase (G to C at c.1180, g.4396, and T to C at c. 1192, g.4408) substituting glycine by arginine (G355R) and arginine by a premature termination (R359X), respectively. In order to demonstrate that G355R/R359X are in cis arrangement, PCR-amplified glucocerebrosidase exon 8 genomic DNA from the patient was cloned into the vector pJET1.2 in Escherichia coli TOP10® strain. Out of the 15 clones that were sequence analyzed, 10 contained the normal allele sequence and 5 contained the complex allele G355R/R359X sequence showing both mutations in cis arrangement. Restriction fragment length polymorphism analysis using Hph1 restriction endonuclease digest was established for the IVS9 + 1G > A mutation for confirmation and efficient identification of this mutation in future patients. Past literature suggests that mutations affecting splicing patterns of the glucocerebrosidase transcript as well as mutations in Gaucher complex alleles are detrimental to enzyme activity. However, compound heterozygosity with N370S, a mild mutation, will lead to a mild phenotype. The cases reported here support these past findings.

  8. Paediatric intestinal cancer and polyposis due to bi-allelic PMS2 mutations : Case series, review and follow-up guidelines

    NARCIS (Netherlands)

    Herkert, Johanna C; Niessen, Renée C; Olderode-Berends, Maria J W; Veenstra-Knol, Hermine E; Vos, Yvonne J; van der Klift, Heleen M; Scheenstra, Rene; Tops, Carli M J; Karrenbeld, Arend; Peters, Frans T M; Hofstra, Robert M W; Kleibeuker, Jan H; Sijmons, Rolf H

    BACKGROUND: Bi-allelic germline mutations of one of the DNA mismatch repair genes, so far predominantly found in PMS2, cause constitutional MMR-deficiency syndrome. This rare disorder is characterised by paediatric intestinal cancer and other malignancies. We report the clinical, immunohistochemical

  9. A new allelic discrimination assay using locked nucleic acid-modified nucleotides (LNA) probes for detection of JAK2 V617F mutation

    Czech Academy of Sciences Publication Activity Database

    Marková, J.; Průková, Dana; Volková, Z.; Schwarz, J.

    2007-01-01

    Roč. 48, č. 3 (2007), s. 638-641 ISSN 1042-8194 Institutional research plan: CEZ:AV0Z50520514 Keywords : Ph1-negative myeloproliferative disorders * JAK2V617F mutation * allelic discrimination Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.512, year: 2007

  10. Associations of common breast cancer susceptibility alleles with risk of breast cancer subtypes in BRCA1 and BRCA2 mutation carriers

    NARCIS (Netherlands)

    Kuchenbaecker, Karoline B.; Neuhausen, Susan L.; Robson, Mark; Barrowdale, Daniel; McGuffog, Lesley; Mulligan, Anna Marie; Andrulis, Irene L.; Spurdle, Amanda B.; Schmidt, Marjanka K.; Schmutzler, Rita K.; Engel, Christoph; Wappenschmidt, Barbara; Nevanlinna, Heli; Thomassen, Mads; Southey, Melissa; Radice, Paolo; Ramus, Susan J.; Domchek, Susan M.; Nathanson, Katherine L.; Lee, Andrew; Healey, Sue; Nussbaum, Robert L.; Rebbeck, Timothy R.; Arun, Banu K.; James, Paul; Karlan, Beth Y.; Lester, Jenny; Cass, Ilana; Terry, Mary Beth; Daly, Mary B.; Goldgar, David E.; Buys, Saundra S.; Janavicius, Ramunas; Tihomirova, Laima; Tung, Nadine; Dorfling, Cecilia M.; van Rensburg, Elizabeth J.; Steele, Linda; v O Hansen, Thomas; Ejlertsen, Bent; Gerdes, Anne-Marie; Nielsen, Finn C.; Dennis, Joe; Cunningham, Julie; Hart, Steven; Slager, Susan; Osorio, Ana; Benitez, Javier; Duran, Mercedes; Weitzel, Jeffrey N.; Tafur, Isaac; Hander, Mary; Peterlongo, Paolo; Manoukian, Siranoush; Peissel, Bernard; Roversi, Gaia; Scuvera, Giulietta; Bonanni, Bernardo; Mariani, Paolo; Volorio, Sara; Dolcetti, Riccardo; Varesco, Liliana; Papi, Laura; Tibiletti, Maria Grazia; Giannini, Giuseppe; Fostira, Florentia; Konstantopoulou, Irene; Garber, Judy; Hamann, Ute; Donaldson, Alan; Brewer, Carole; Foo, Claire; Evans, D. Gareth; Frost, Debra; Eccles, Diana; Douglas, Fiona; Brady, Angela; Cook, Jackie; Tischkowitz, Marc; Adlard, Julian; Barwell, Julian; Ong, Kai-Ren; Walker, Lisa; Izatt, Louise; Side, Lucy E.; Kennedy, M. John; Rogers, Mark T.; Porteous, Mary E.; Morrison, Patrick J.; Platte, Radka; Eeles, Ros; Davidson, Rosemarie; Hodgson, Shirley; Ellis, Steve; Godwin, Andrew K.; Rhiem, Kerstin; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Plendl, Hansjoerg; Niederacher, Dieter; Sutter, Christian; Steinemann, Doris; Bogdanova-Markov, Nadja; Kast, Karin; Varon-Mateeva, Raymonda; Wang-Gohrke, Shan; Gehrig, Andrea; Markiefka, Birgid; Buecher, Bruno; Lefol, Cédrick; Stoppa-Lyonnet, Dominique; Rouleau, Etienne; Prieur, Fabienne; Damiola, Francesca; Barjhoux, Laure; Faivre, Laurence; Longy, Michel; Sevenet, Nicolas; Sinilnikova, Olga M.; Mazoyer, Sylvie; Bonadona, Valérie; Caux-Moncoutier, Virginie; Isaacs, Claudine; van Maerken, Tom; Claes, Kathleen; Piedmonte, Marion; Andrews, Lesley; Hays, John; Rodriguez, Gustavo C.; Caldes, Trinidad; de la Hoya, Miguel; Khan, Sofia; Hogervorst, Frans B. L.; Aalfs, Cora M.; de Lange, J. L.; Meijers-Heijboer, Hanne E. J.; van der Hout, Annemarie H.; Wijnen, Juul T.; van Roozendaal, K. E. P.; Mensenkamp, Arjen R.; van den Ouweland, Ans M. W.; van Deurzen, Carolien H. M.; van der Luijt, Rob B.; Olah, Edith; Diez, Orland; Lazaro, Conxi; Blanco, Ignacio; Teulé, Alex; Menendez, Mireia; Jakubowska, Anna; Lubinski, Jan; Cybulski, Cezary; Gronwald, Jacek; Jaworska-Bieniek, Katarzyna; Durda, Katarzyna; Arason, Adalgeir; Maugard, Christine; Soucy, Penny; Montagna, Marco; Agata, Simona; Teixeira, Manuel R.; Olswold, Curtis; Lindor, Noralane; Pankratz, Vernon S.; Hallberg, Emily; Wang, Xianshu; Szabo, Csilla I.; Vijai, Joseph; Jacobs, Lauren; Corines, Marina; Lincoln, Anne; Berger, Andreas; Fink-Retter, Anneliese; Singer, Christian F.; Rappaport, Christine; Kaulich, Daphne Gschwantler; Pfeiler, Georg; tea, Muy-Kheng; Phelan, Catherine M.; Mai, Phuong L.; Greene, Mark H.; Rennert, Gad; Imyanitov, Evgeny N.; Glendon, Gord; Toland, Amanda Ewart; Bojesen, Anders; Pedersen, Inge Sokilde; Jensen, Uffe Birk; Caligo, Maria A.; Friedman, Eitan; Berger, Raanan; Laitman, Yael; Rantala, Johanna; Arver, Brita; Loman, Niklas; Borg, Ake; Ehrencrona, Hans; Olopade, Olufunmilayo I.; Simard, Jacques; Easton, Douglas F.; Chenevix-Trench, Georgia; Offit, Kenneth; Couch, Fergus J.; Antoniou, Antonis C.; Perkins, Jo; Miedzybrodzka, Zosia; Gregory, Helen; Morrison, Patrick; Jeffers, Lisa; Cole, Trevor; Hoffman, Jonathan; James, Margaret; Paterson, Joan; Downing, Sarah; Taylor, Amy; Murray, Alexandra; McCann, Emma; Barton, David; Porteous, Mary; Drummond, Sarah; Kivuva, Emma; Searle, Anne; Goodman, Selina; Hill, Kathryn; Murday, Victoria; Bradshaw, Nicola; Snadden, Lesley; Longmuir, Mark; Watt, Catherine; Gibson, Sarah; Haque, Eshika; Tobias, Ed; Duncan, Alexis; Jacobs, Chris; Langman, Caroline; Dorkins, Huw; Serra-Feliu, Gemma; Ellis, Ian; Lalloo, Fiona; Taylor, Jane; Side, Lucy; Male, Alison; Berlin, Cheryl; Eason, Jacqueline; Collier, Rebecca; Claber, Oonagh; Jobson, Irene; McLeod, Diane; Halliday, Dorothy; Durell, Sarah; Stayner, Barbara; Shanley, Susan; Rahman, Nazneen; Houlston, Richard; Bancroft, Elizabeth; Page, Elizabeth; Ardern-Jones, Audrey; Kohut, Kelly; Wiggins, Jennifer; Castro, Elena; Mitra, Anita; Quarrell, Oliver; Bardsley, Cathryn; Goff, Sheila; Brice, Glen; Winchester, Lizzie; Eddy, Charlotte; Tripathi, Vishakha; Attard, Virginia; Lucassen, Anneke; Crawford, Gillian; McBride, Donna; Smalley, Sarah; Weaver, Joellen; Bove, Betsy; Sinilnikova, Olga; Verny-Pierre, Carole; Calender, Alain; Giraud, Sophie; Léone, Mélanie; Gauthier-Villars, Marion; Houdayer, Claude; Moncoutier, Virginie; Belotti, Muriel; Tirapo, Carole; de Pauw, Antoine; Bressac-de-Paillerets, Brigitte; Caron, Olivier; Bignon, Yves-Jean; Uhrhammer, Nancy; Lasset, Christine; Handallo, Sandrine; Hardouin, Agnès; Berthet, Pascaline; Sobol, Hagay; Bourdon, Violaine; Noguchi, Tetsuro; Remenieras, Audrey; Eisinger, François; Coupier, Isabelle; Pujol, Pascal; Peyrat, Jean-Philippe; Fournier, Joëlle; Révillion, Françoise; Vennin, Philippe; Adenis, Claude; Lidereau, Rosette; Demange, Liliane; Nogues, Catherine; Muller, Danièle; Fricker, Jean-Pierre; Barouk-Simonet, Emmanuelle; Bonnet, Françoise; Bubien, Virginie; Toulas, Christine; Guimbaud, Rosine; Gladieff, Laurence; Feillel, Viviane; Leroux, Dominique; Dreyfus, Hélène; Rebischung, Christine; Peysselon, Magalie; Coron, Fanny; Lebrun, Marine; Kientz, Caroline; Ferrer, Sandra Fert; Frénay, Marc; Vénat-Bouvet, Laurence; Delnatte, Capucine; Mortemousque, Isabelle; Coulet, Florence; Colas, Chrystelle; Soubrier, Florent; Sokolowska, Johanna; Bronner, Myriam; Collonge-Rame, Marie-Agnès; Damette, Alexandre; Lynch, Henry T.; Snyder, Carrie L.; Coene, Ilse; Crombez, Brecht; Segura, Pedro Perez; Romero, Atocha; Diaque, Paula; Aittomäki, Kristiina; Blomqvist, Carl; Aaltonen, Kirsimari; Muranen, Taru A.; Erkkilä, Irja; Palola, Virpi; Rookus, M. A.; Hogervorst, F. B. L.; van Leeuwen, F. E.; Verhoef, S.; Schmidt, M. K.; Wijnands, R.; Collée, J. M.; van den Ouweland, A. M. W.; Hooning, M. J.; Seynaeve, C.; van Deurzen, C. H. M.; Obdeijn, I. M.; van Asperen, C. J.; Wijnen, J. T.; Tollenaar, R. A. E. M.; Devilee, P.; van Cronenburg, T. C. T. E. F.; Kets, C. M.; Mensenkamp, A. R.; Ausems, M. G. E. M.; van der Luijt, R. B.; van Os, T. A. M.; Gille, J. J. P.; Waisfisz, Q.; Gómez-Garcia, E. B.; Blok, M. J.; Oosterwijk, J. C.; van der Hout, A. H.; Mourits, M. J.; de Bock, G. H.; Vasen, H. F.; Siesling, S.; Overbeek, L. I. H.; Papp, Janos; Vaszko, Tibor; Bozsik, Aniko; Pocza, Timea; Franko, Judit; Balogh, Maria; Domokos, Gabriella; Ferenczi, Judit; Balmaña, J.; Capella, Gabriel; Dumont, Martine; Tranchant, Martine

    2014-01-01

    Introduction: More than 70 common alleles are known to be involved in breast cancer (BC) susceptibility, and several exhibit significant heterogeneity in their associations with different BC subtypes. Although there are differences in the association patterns between BRCA1 and BRCA2 mutation

  11. Molecular analysis of two mouse dilute locus deletion mutations: Spontaneous dilute lethal20J and radiation-induced dilute prenatal lethal Aa2 alleles

    International Nuclear Information System (INIS)

    Strobel, M.C.; Seperack, P.K.; Copeland, N.G.; Jenkins, N.A.

    1990-01-01

    The dilute (d) coat color locus of mouse chromosome 9 has been identified by more than 200 spontaneous and mutagen-induced recessive mutations. With the advent of molecular probes for this locus, the molecular lesion associated with different dilute alleles can be recognized and precisely defined. In this study, two dilute mutations, dilute-lethal20J (dl20J) and dilute prenatal lethal Aa2, have been examined. Using a dilute locus genomic probe in Southern blot analysis, we detected unique restriction fragments in dl20J and Aa2 DNA. Subsequent analysis of these fragments showed that they represented deletion breakpoint fusion fragments. DNA sequence analysis of each mutation-associated deletion breakpoint fusion fragment suggests that both genomic deletions were generated by nonhomologous recombination events. The spontaneous dl20J mutation is caused by an interstitial deletion that removes a single coding exon of the dilute gene. The correlation between this discrete deletion and the expression of all dilute-associated phenotypes in dl20J homozygotes defines the dl20J mutation as a functional null allele of the dilute gene. The radiation-induced Aa2 allele is a multilocus deletion that, by complementation analysis, affects both the dilute locus and the proximal prenatal lethal-3 (pl-3) functional unit. Molecular analysis of the Aa2 deletion breakpoint fusion fragment has provided access to a previously undefined gene proximal to d. Initial characterization of this new gene suggests that it may represent the genetically defined pl-3 functional unit

  12. WASP: a Web-based Allele-Specific PCR assay designing tool for detecting SNPs and mutations

    Directory of Open Access Journals (Sweden)

    Assawamakin Anunchai

    2007-08-01

    Full Text Available Abstract Background Allele-specific (AS Polymerase Chain Reaction is a convenient and inexpensive method for genotyping Single Nucleotide Polymorphisms (SNPs and mutations. It is applied in many recent studies including population genetics, molecular genetics and pharmacogenomics. Using known AS primer design tools to create primers leads to cumbersome process to inexperience users since information about SNP/mutation must be acquired from public databases prior to the design. Furthermore, most of these tools do not offer the mismatch enhancement to designed primers. The available web applications do not provide user-friendly graphical input interface and intuitive visualization of their primer results. Results This work presents a web-based AS primer design application called WASP. This tool can efficiently design AS primers for human SNPs as well as mutations. To assist scientists with collecting necessary information about target polymorphisms, this tool provides a local SNP database containing over 10 million SNPs of various populations from public domain databases, namely NCBI dbSNP, HapMap and JSNP respectively. This database is tightly integrated with the tool so that users can perform the design for existing SNPs without going off the site. To guarantee specificity of AS primers, the proposed system incorporates a primer specificity enhancement technique widely used in experiment protocol. In particular, WASP makes use of different destabilizing effects by introducing one deliberate 'mismatch' at the penultimate (second to last of the 3'-end base of AS primers to improve the resulting AS primers. Furthermore, WASP offers graphical user interface through scalable vector graphic (SVG draw that allow users to select SNPs and graphically visualize designed primers and their conditions. Conclusion WASP offers a tool for designing AS primers for both SNPs and mutations. By integrating the database for known SNPs (using gene ID or rs number

  13. Non-syndromic hearing impairment in India: high allelic heterogeneity among mutations in TMPRSS3, TMC1, USHIC, CDH23 and TMIE.

    Directory of Open Access Journals (Sweden)

    Aparna Ganapathy

    Full Text Available Mutations in the autosomal genes TMPRSS3, TMC1, USHIC, CDH23 and TMIE are known to cause hereditary hearing loss. To study the contribution of these genes to autosomal recessive, non-syndromic hearing loss (ARNSHL in India, we examined 374 families with the disorder to identify potential mutations. We found four mutations in TMPRSS3, eight in TMC1, ten in USHIC, eight in CDH23 and three in TMIE. Of the 33 potentially pathogenic variants identified in these genes, 23 were new and the remaining have been previously reported. Collectively, mutations in these five genes contribute to about one-tenth of ARNSHL among the families examined. New mutations detected in this study extend the allelic heterogeneity of the genes and provide several additional variants for structure-function correlation studies. These findings have implications for early DNA-based detection of deafness and genetic counseling of affected families in the Indian subcontinent.

  14. Detection of EGFR mutations in plasma and biopsies from non-small cell lung cancer patients by allele-specific PCR assays

    DEFF Research Database (Denmark)

    Weber, Britta; Meldgaard, Peter; Hager, Henrik

    2014-01-01

    samples with allele-specific PCR assays. METHODS: Pairs of the diagnostic biopsy and plasma obtained just prior to start of erlotinib treatment were collected from 199 patients with adenocarcinoma of non-small-cell lung cancer. DNA from both sample types was isolated and examined for the presence...... of mutations in exons 18-21 of the EGFR gene, employing the cobas(®) EGFR Tissue Test and cobas(®) EGFR Blood Test (in development, Roche Molecular Systems, Inc., CA, USA). RESULTS: Test results were obtained in all 199 (100%) plasma samples and 196/199 (98%) of the biopsies. EGFR-activating mutations were...... identified in 24/199 (12%) plasma samples and 28/196 (14%) biopsy samples, and 17/196 (9%) matched pairs contained the same mutation. Six EGFR mutations were present only in plasma samples but not in the biopsy samples. The overall concordance of the EGFR gene mutations detected in plasma and biopsy tissue...

  15. siRNA-mediated Allele-specific Silencing of a COL6A3 Mutation in a Cellular Model of Dominant Ullrich Muscular Dystrophy

    Directory of Open Access Journals (Sweden)

    Véronique Bolduc

    2014-01-01

    Full Text Available Congenital muscular dystrophy type Ullrich (UCMD is a severe disorder of early childhood onset for which currently there is no effective treatment. UCMD commonly is caused by dominant-negative mutations in the genes coding for collagen type VI, a major microfibrillar component of the extracellular matrix surrounding the muscle fibers. To explore RNA interference (RNAi as a potential therapy for UCMD, we designed a series of small interfering RNA (siRNA oligos that specifically target the most common mutations resulting in skipping of exon 16 in the COL6A3 gene and tested them in UCMD-derived dermal fibroblasts. Transcript analysis by semiquantitative and quantitative reverse transcriptase PCR showed that two of these siRNAs were the most allele-specific, i.e., they efficiently knocked down the expression from the mutant allele, without affecting the normal allele. In HEK293T cells, these siRNAs selectively suppressed protein expression from a reporter construct carrying the mutation, with no or minimal suppression of the wild-type (WT construct, suggesting that collagen VI protein levels are as also reduced in an allele-specific manner. Furthermore, we found that treating UCMD fibroblasts with these siRNAs considerably improved the quantity and quality of the collagen VI matrix, as assessed by confocal microscopy. Our current study establishes RNAi as a promising molecular approach for treating dominant COL6-related dystrophies.

  16. Paediatric intestinal cancer and polyposis due to bi-allelic PMS2 mutations: case series, review and follow-up guidelines.

    Science.gov (United States)

    Herkert, Johanna C; Niessen, Renée C; Olderode-Berends, Maria J W; Veenstra-Knol, Hermine E; Vos, Yvonne J; van der Klift, Heleen M; Scheenstra, Rene; Tops, Carli M J; Karrenbeld, Arend; Peters, Frans T M; Hofstra, Robert M W; Kleibeuker, Jan H; Sijmons, Rolf H

    2011-05-01

    Bi-allelic germline mutations of one of the DNA mismatch repair genes, so far predominantly found in PMS2, cause constitutional MMR-deficiency syndrome. This rare disorder is characterised by paediatric intestinal cancer and other malignancies. We report the clinical, immunohistochemical and genetic characterisation of four families with bi-allelic germline PMS2 mutations. We present an overview of the published gastrointestinal manifestations of CMMR-D syndrome and propose recommendations for gastro-intestinal screening. The first proband developed a cerebral angiosarcoma at age 2 and two colorectal adenomas at age 7. Genetic testing identified a complete PMS2 gene deletion and a frameshift c.736_741delinsTGTGTGTGAAG (p.Pro246CysfsX3) mutation. In the second family, both the proband and her brother had multiple intestinal adenomas, initially wrongly diagnosed as familial adenomatous polyposis. A splice site c.2174+1G>A, and a missense c.137G>T (p.Ser46Ile) mutation in PMS2 were identified. The third patient was diagnosed with multiple colorectal adenomas at age 11; he developed a high-grade dysplastic colorectal adenocarcinoma at age 21. Two intragenic PMS2 deletions were found. The fourth proband developed a cerebral anaplastic ganglioma at age 9 and a high-grade colerectal dysplastic adenoma at age 10 and carries a homozygous c.2174+1G>A mutation. Tumours of all patients showed microsatellite instability and/or loss of PMS2 expression. Our findings show the association between bi-allelic germline PMS2 mutations and severe childhood-onset gastrointestinal manifestations, and support the notion that patients with early-onset gastrointestinal adenomas and cancer should be investigated for CMMR-D syndrome. We recommend yearly follow-up with colonoscopy from age 6 and simultaneous video-capsule small bowel enteroscopy from age 8. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. In Vivo-Selected Compensatory Mutations Restore the Fitness Cost of Mosaic penA Alleles That Confer Ceftriaxone Resistance in Neisseria gonorrhoeae

    Directory of Open Access Journals (Sweden)

    Leah R. Vincent

    2018-04-01

    Full Text Available Resistance to ceftriaxone in Neisseria gonorrhoeae is mainly conferred by mosaic penA alleles that encode penicillin-binding protein 2 (PBP2 variants with markedly lower rates of acylation by ceftriaxone. To assess the impact of these mosaic penA alleles on gonococcal fitness, we introduced the mosaic penA alleles from two ceftriaxone-resistant (Cror clinical isolates (H041 and F89 into a Cros strain (FA19 by allelic exchange and showed that the resultant Cror mutants were significantly outcompeted by the Cros parent strain in vitro and in a murine infection model. Four Cror compensatory mutants of FA19 penA41 were isolated independently from mice that outcompeted the parent strain both in vitro and in vivo. One of these compensatory mutants (LV41C displayed a unique growth profile, with rapid log growth followed by a sharp plateau/gradual decline at stationary phase. Genome sequencing of LV41C revealed a mutation (G348D in the acnB gene encoding the bifunctional aconitate hydratase 2/2 methylisocitrate dehydratase. Introduction of the acnBG348D allele into FA19 penA41 conferred both a growth profile that phenocopied that of LV41C and a fitness advantage, although not as strongly as that exhibited by the original compensatory mutant, suggesting the existence of additional compensatory mutations. The mutant aconitase appears to be a functional knockout with lower activity and expression than wild-type aconitase. Transcriptome sequencing (RNA-seq analysis of FA19 penA41 acnBG348D revealed a large set of upregulated genes involved in carbon and energy metabolism. We conclude that compensatory mutations can be selected in Cror gonococcal strains that increase metabolism to ameliorate their fitness deficit.

  18. Melting curve analysis after T allele enrichment (MelcaTle as a highly sensitive and reliable method for detecting the JAK2V617F mutation.

    Directory of Open Access Journals (Sweden)

    Soji Morishita

    Full Text Available Detection of the JAK2V617F mutation is essential for diagnosing patients with classical myeloproliferative neoplasms (MPNs. However, detection of the low-frequency JAK2V617F mutation is a challenging task due to the necessity of discriminating between true-positive and false-positive results. Here, we have developed a highly sensitive and accurate assay for the detection of JAK2V617F and named it melting curve analysis after T allele enrichment (MelcaTle. MelcaTle comprises three steps: 1 two cycles of JAK2V617F allele enrichment by PCR amplification followed by BsaXI digestion, 2 selective amplification of the JAK2V617F allele in the presence of a bridged nucleic acid (BNA probe, and 3 a melting curve assay using a BODIPY-FL-labeled oligonucleotide. Using this assay, we successfully detected nearly a single copy of the JAK2V617F allele, without false-positive signals, using 10 ng of genomic DNA standard. Furthermore, MelcaTle showed no positive signals in 90 assays screening healthy individuals for JAK2V617F. When applying MelcaTle to 27 patients who were initially classified as JAK2V617F-positive on the basis of allele-specific PCR analysis and were thus suspected as having MPNs, we found that two of the patients were actually JAK2V617F-negative. A more careful clinical data analysis revealed that these two patients had developed transient erythrocytosis of unknown etiology but not polycythemia vera, a subtype of MPNs. These findings indicate that the newly developed MelcaTle assay should markedly improve the diagnosis of JAK2V617F-positive MPNs.

  19. Common breast cancer susceptibility alleles are associated with tumour subtypes in BRCA1 and BRCA2 mutation carriers: results from the Consortium of Investigators of Modifiers of BRCA1/2

    NARCIS (Netherlands)

    Mulligan, Anna Marie; Couch, Fergus J.; Barrowdale, Daniel; Domchek, Susan M.; Eccles, Diana; Nevanlinna, Heli; Ramus, Susan J.; Robson, Mark; Sherman, Mark; Spurdle, Amanda B.; Wappenschmidt, Barbara; Lee, Andrew; McGuffog, Lesley; Healey, Sue; Sinilnikova, Olga M.; Janavicius, Ramunas; Hansen, Thomas vO; Nielsen, Finn C.; Ejlertsen, Bent; Osorio, Ana; Muñoz-Repeto, Iván; Durán, Mercedes; Godino, Javier; Pertesi, Maroulio; Benítez, Javier; Peterlongo, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Cattaneo, Elisa; Bonanni, Bernardo; Viel, Alessandra; Pasini, Barbara; Papi, Laura; Ottini, Laura; Savarese, Antonella; Bernard, Loris; Radice, Paolo; Hamann, Ute; Verheus, Martijn; Meijers-Heijboer, Hanne E. J.; Wijnen, Juul; Gómez García, Encarna B.; Nelen, Marcel R.; Kets, C. Marleen; Seynaeve, Caroline; Tilanus-Linthorst, Madeleine M. A.; van der Luijt, Rob B.; van Os, Theo; Rookus, Matti; Frost, Debra; Jones, J. Louise; Evans, D. Gareth; Lalloo, Fiona; Eeles, Ros; Izatt, Louise; Adlard, Julian; Davidson, Rosemarie; Cook, Jackie; Donaldson, Alan; Dorkins, Huw; Gregory, Helen; Eason, Jacqueline; Houghton, Catherine; Barwell, Julian; Side, Lucy E.; McCann, Emma; Murray, Alex; Peock, Susan; Godwin, Andrew K.; Schmutzler, Rita K.; Rhiem, Kerstin; Engel, Christoph; Meindl, Alfons; Ruehl, Ina; Arnold, Norbert; Niederacher, Dieter; Sutter, Christian; Deissler, Helmut; Gadzicki, Dorothea; Kast, Karin; Preisler-Adams, Sabine; Varon-Mateeva, Raymonda; Schoenbuchner, Ines; Fiebig, Britta; Heinritz, Wolfram; Schäfer, Dieter; Gevensleben, Heidrun; Caux-Moncoutier, Virginie; Fassy-Colcombet, Marion; Cornelis, François; Mazoyer, Sylvie; Léoné, Mélanie; Boutry-Kryza, Nadia; Hardouin, Agnès; Berthet, Pascaline; Muller, Danièle; Fricker, Jean-Pierre; Mortemousque, Isabelle; Pujol, Pascal; Coupier, Isabelle; Lebrun, Marine; Kientz, Caroline; Longy, Michel; Sevenet, Nicolas; Stoppa-Lyonnet, Dominique; Isaacs, Claudine; Caldes, Trinidad; de la Hoya, Miguel; Heikkinen, Tuomas; Aittomäki, Kristiina; Blanco, Ignacio; Lazaro, Conxi; Barkardottir, Rosa B.; Soucy, Penny; Dumont, Martine; Simard, Jacques; Montagna, Marco; Tognazzo, Silvia; D'Andrea, Emma; Fox, Stephen; Yan, Max; Rebbeck, Tim; Olopade, Olufunmilayo; Weitzel, Jeffrey N.; Lynch, Henry T.; Ganz, Patricia A.; Tomlinson, Gail E.; Wang, Xianshu; Fredericksen, Zachary; Pankratz, Vernon S.; Lindor, Noralane M.; Szabo, Csilla; Offit, Kenneth; Sakr, Rita; Gaudet, Mia; Bhatia, Jasmine; Kauff, Noah; Singer, Christian F.; tea, Muy-Kheng; Gschwantler-Kaulich, Daphne; Fink-Retter, Anneliese; Mai, Phuong L.; Greene, Mark H.; Imyanitov, Evgeny; O'Malley, Frances P.; Ozcelik, Hilmi; Glendon, Gordon; Toland, Amanda E.; Gerdes, Anne-Marie; Thomassen, Mads; Kruse, Torben A.; Jensen, Uffe Birk; Skytte, Anne-Bine; Caligo, Maria A.; Soller, Maria; Henriksson, Karin; Wachenfeldt, von Anna; Arver, Brita; Stenmark-Askmalm, Marie; Karlsson, Per; Ding, Yuan Chun; Neuhausen, Susan L.; Beattie, Mary; Pharoah, Paul D. P.; Moysich, Kirsten B.; Nathanson, Katherine L.; Karlan, Beth Y.; Gross, Jenny; John, Esther M.; Daly, Mary B.; Buys, Saundra M.; Southey, Melissa C.; Hopper, John L.; Terry, Mary Beth; Chung, Wendy; Miron, Alexander F.; Goldgar, David; Chenevix-Trench, Georgia; Easton, Douglas F.; Andrulis, Irene L.; Antoniou, Antonis C.; Ellis, Steve; Fineberg, Elena; Platte, Radka; Miedzybrodzka, Zosia; Morrison, Patrick; Jeffers, Lisa; Cole, Trevor; Ong, Kai-Ren; Hoffman, Jonathan; James, Margaret; Paterson, Joan; Downing, Sarah; Taylor, Amy; Rogers, T.; Kennedy, John M.; Barton, David; Porteous, Mary; Drummond, Sarah; Brewer, Carole; Kivuva, Emma; Searle, Anne; Goodman, Selina; Hill, Kathryn; Murday, Victoria; Bradshaw, Nicola; Snadden, Lesley; Longmuir, Mark; Watt, Catherine; Gibson, Sarah; Haque, Eshika; Tobias, Ed; Duncan, Alexis; Jacobs, Chris; Langman, Caroline; Whaite, Anna; Chu, Carol; Miller, Julie; Ellis, Ian; Taylor, Jane; Male, Alison; Berlin, Cheryl; Collier, Rebecca; Douglas, Fiona; Claber, Oonagh; Jobson, Irene; Walker, Lisa; McLeod, Diane; Halliday, Dorothy; Durell, Sarah; Stayner, Barbara; Shanley, Susan; Rahman, Nazneen; Houlston, Richard; Bancroft, Elizabeth; D'Mello, Lucia; Page, Elizabeth; Ardern-Jones, Audrey; Kohut, Kelly; Wiggins, Jennifer; Castro, Elena; Mitra, Anita; Robertson, Lisa; Quarrell, Oliver; Bardsley, Cathryn; Hodgson, Shirley; Goff, Sheila; Brice, Glen; Winchester, Lizzie; Eddy, Charlotte; Tripathi, Vishakha; Attard, Virginia; Lucassen, Anneke; Crawford, Gillian; McBride, Donna; Smalley, Sarah; Barjhoux, Laure; Verny-Pierre, Carole; Giraud, Sophie; Gauthier-Villars, Marion; Buecher, Bruno; Houdayer, Claude; Belotti, Muriel; Tirapo, Carole; de Pauw, Antoine; Roussy, Gustave; Bressac-de-Paillerets, Brigitte; Remenieras, Audrey; Byrde, Véronique; Caron, Olivier; Lenoir, Gilbert; Bignon, Yves-Jean; Uhrhammer, Nancy; Bérard, Léon; Lasset, Christine; Bonadona, Valérie; Baclesse, François; Sobol, Hagay; Bourdon, Violaine; Noguchi, Tetsuro; Eisinger, François; Coulet, Florence; Colas, Chrystelle; Soubrier, Florent; Peyrat, Jean-Philippe; Fournier, Joëlle; Révillion, Françoise; Vennin, Philippe; Adenis, Claude; Rouleau, Etienne; Lidereau, Rosette; Demange, Liliane; Nogues, Catherine; Barouk-Simonet, Emmanuelle; Bonnet, Françoise; Bubien, Virginie; Toulas, Christine; Guimbaud, Rosine; Gladieff, Laurence; Feillel, Viviane; Leroux, Dominique; Dreyfus, Hélène; Rebischung, Christine; Peysselon, Magalie; Coron, Fanny; Faivre, Laurence; Prieur, Fabienne; Ferrer, Sandra Fert; Lacassagne, Antoine; Frénay, Marc; Vénat-Bouvet, Laurence; Delnatte, Capucine; Snyder, Carrie L.; Hogervorst, F. B. L.; Verhoef, S.; Verheus, M.; van 't Veer, L. J.; van Leeuwen, F. E.; Collée, M.; van den Ouweland, A. M. W.; Jager, A.; Hooning, M. J.; van Asperen, C. J.; Wijnen, J. T.; Vreeswijk, M. P.; Tollenaar, R. A.; Devilee, P.; Ligtenberg, M. J.; Hoogerbrugge, N.; Ausems, M. G.; Aalfs, C. M.; Gille, J. J. P.; Waisfisz, Q.; Gomez-Garcia, E. B.; van Roozendaal, C. E.; Blok, Marinus J.; Caanen, B.; Oosterwijk, J. C.; van der Hout, A. H.; Mourits, M. J.; Vasen, H. F.; Nordling, Margareta; Bergman, Annika; Einbeigi, Zakaria; Liedgren, Sigrun; Borg, Åke; Loman, Niklas; Olsson, Håkan; Kristoffersson, Ulf; Jernström, Helena; Harbst, Katja; Lindblom, Annika; Liljegren, Annelie; Barbany-Bustinza, Gisela; Rantala, Johanna; Melin, Beatrice; Grönberg, Henrik; Stattin, Eva-Lena; Emanuelsson, Monica; Ehrencrona, Hans; Rosenquist, Richard; Dahl, Niklas

    2011-01-01

    Previous studies have demonstrated that common breast cancer susceptibility alleles are differentially associated with breast cancer risk for BRCA1 and/or BRCA2 mutation carriers. It is currently unknown how these alleles are associated with different breast cancer subtypes in BRCA1 and BRCA2

  20. Common breast cancer susceptibility alleles are associated with tumour subtypes in BRCA1 and BRCA2 mutation carriers: results from the Consortium of Investigators of Modifiers of BRCA1/2

    NARCIS (Netherlands)

    A.M. Mulligan (Anna Marie); F.J. Couch (Fergus); D. Barrowdale (Daniel); S.M. Domchek (Susan); D. Eccles (Diana); H. Nevanlinna (Heli); S.J. Ramus (Susan); M. Robson (Mark); M.E. Sherman (Mark); A.B. Spurdle (Amanda); B. Wapenschmidt (Barbara); A. Lee (Andrew); L. McGuffog (Lesley); S. Healey (Sue); O. Sinilnikova (Olga); R. Janavicius (Ramunas); T.V.O. Hansen (Thomas); F.C. Nielsen (Finn); B. Ejlertsen (Bent); A. Osorio (Ana); I. Muñoz-Repeto (Iván); M. Durán (Mercedes); J. Godino (Javier); M. Pertesi (Maroulio); J. Benítez (Javier); P. Peterlongo (Paolo); S. Manoukian (Siranoush); B. Peissel (Bernard); D. Zaffaroni (D.); E. Cattaneo (Elisa); B. Bonnani (Bernardo); A. Viel (Alessandra); B. Pasini (Barbara); L. Papi (Laura); L. Ottini (Laura); A. Savarese (Antonella); L. Bernard (Loris); P. Radice (Paolo); U. Hamann (Ute); M. Verheus (Martijn); E.J. Meijers-Heijboer (Hanne); J.T. Wijnen (Juul); E.B. Gómez García (Encarna); M.R. Nelen (Marcel); C.M. Kets; C.M. Seynaeve (Caroline); M.M.A. Tilanus-Linthorst (Madeleine); R.B. van der Luijt (Rob); T.V. Os (Theo); M.A. Rookus (Matti); D. Frost (Debra); J.L. Jones (J Louise); D.G. Evans (Gareth); F. Lalloo (Fiona); R. Eeles (Rosalind); L. Izatt (Louise); J.W. Adlard (Julian); R. Davidson (Rosemarie); J. Cook (Jackie); A. Donaldson (Alan); H. Dorkins (Huw); H. Gregory (Helen); J. Eason (Jacqueline); C. Houghton (Catherine); J. Barwell (Julian); L. Side (Lucy); E. McCann (Emma); A. Murray (Alexandra); S. Peock (Susan); A.K. Godwin (Andrew); R.K. Schmutzler (Rita); K. Rhiem (Kerstin); C.W. Engel (Christoph); A. Meindl (Alfons); I. Ruehl (Ina); N. Arnold (Norbert); D. Niederacher (Dieter); C. Sutter (Christian); H. Deissler (Helmut); D. Gadzicki (Dorothea); K. Kast (Karin); S. Preisler-Adams (Sabine); R. Varon-Mateeva (Raymonda); I. Schoenbuchner (Ines); B. Fiebig (Britta); W. Heinritz (Wolfram); D. Schäfer (Dieter); H. Gevensleben (Heidrun); V. Caux-Moncoutier (Virginie); M. Fassy-Colcombet (Marion); F. Cornelis (Franco̧is); S. Mazoyer (Sylvie); M. Léone (Mélanie); N. Boutry-Kryza (N.); A. Hardouin (Agnès); P. Berthet (Pascaline); D.W. Muller (Danièle); J.P. Fricker (Jean Pierre); I. Mortemousque (Isabelle); P. Pujol (Pascal); I. Coupier (Isabelle); M. Lebrun (Marine); C. Kientz (Caroline); M. Longy (Michel); N. Sevenet (Nicolas); D. Stoppa-Lyonnet (Dominique); C. Isaacs (Claudine); T. Caldes (Trinidad); M. de La Hoya (Miguel); T. Heikinen (Tuomas); K. Aittomäki (Kristiina); I. Blanco (Ignacio); C. Lazaro (Conxi); R.B. Barkardottir (Rosa); P. Soucy (Penny); M. Dumont (Martine); J. Simard (Jacques); M. Montagna (Marco); S. Tognazzo (Silvia); E. D'Andrea (Emma); S.B. Fox (Stephen); M. Yan (Max); R. Rebbeck (Timothy); O.I. Olopade (Olofunmilayo); J.N. Weitzel (Jeffrey); H. Lynch (Henry); P.A. Ganz (Patricia); G. Tomlinson (Gail); X. Wang (Xing); Z. Fredericksen (Zachary); V.S. Pankratz (Shane); N.M. Lindor (Noralane); C. Szabo (Csilla); K. Offit (Kenneth); R. Sakr (Rita); M.M. Gaudet (Mia); K.P. Bhatia (Kailash); N. Kauff (Noah); C.F. Singer (Christian); M.-K. Tea; D. Gschwantler-Kaulich (Daphne); A. Fink-Retter (Anneliese); P.L. Mai (Phuong); M.H. Greene (Mark); E.N. Imyanitov (Evgeny); F.P. O'Malley (Frances); H. Ozcelik (Hilmi); G. Glendon (Gord); A.E. Toland (Amanda); A-M. Gerdes (Anne-Marie); M. Thomassen (Mads); T.A. Kruse (Torben); U.B. Jensen; A.-B. Skytte (Anne-Bine); M.A. Caligo (Maria); M. Soller (Maria); K. Henriksson (Karin); A. von Wachenfeldt (Anna); B. Arver (Brita Wasteson); M. Stenmark-Askmalm (M.); P. Karlsson (Per); Y.C. Ding (Yuan); S.L. Neuhausen (Susan); M.S. Beattie (Mary); P.D.P. Pharoah (Paul); K.B. Moysich (Kirsten); K.L. Nathanson (Katherine); B.Y. Karlan (Beth); J. Gross (Jenny); E.M. John (Esther); M.B. Daly (Mary); S.S. Buys (Saundra); M.C. Southey (Melissa); J.L. Hopper (John); M.-B. Terry (Mary-Beth); W. Chung (Wendy); A. Miron (Alexander); D. Goldgar (David); G. Chenevix-Trench (Georgia); D.F. Easton (Douglas); I.L. Andrulis (Irene); A.C. Antoniou (Antonis)

    2011-01-01

    textabstractIntroduction: Previous studies have demonstrated that common breast cancer susceptibility alleles are differentially associated with breast cancer risk for BRCA1 and/or BRCA2 mutation carriers. It is currently unknown how these alleles are associated with different breast cancer subtypes

  1. Alpha-1 antitrypsin deficiency caused by a novel mutation (p.Leu263Pro: Pi*ZQ0gaia – Q0gaia allele

    Directory of Open Access Journals (Sweden)

    M.J. Oliveira

    2015-11-01

    Full Text Available Severe alpha-1 antitrypsin deficiency (AATD is generally associated with PI*ZZ genotype and less often with combinations of PI*Z, PI*S, and other rarer deficiency or null (Q0 alleles. Severe AATD predisposes patients to various diseases, including pulmonary emphysema. Presented here is a case report of a young man with COPD and AATD. The investigation of the AATD showed a novel mutation p.Leu263Pro (c.860T>C, which was named Q0gaia (Pi*ZQ0gaia. Q0gaia is associated with very low or no detectable serum concentrations of AAT. Keywords: Alpha-1 antitrypsin deficiency, Null allele, COPD

  2. Concurrent MPL515 and JAK2V617F mutations in myelofibrosis: chronology of clonal emergence and changes in mutant allele burden over time.

    Science.gov (United States)

    Lasho, Terra L; Pardanani, Animesh; McClure, Rebecca F; Mesa, Ruben A; Levine, Ross L; Gilliland, D Gary; Tefferi, Ayalew

    2006-12-01

    MPLW515L/K and JAK2V617F can co-exist in myelofibrosis with myeloid metaplasia (MMM). The chronology of clonal emergence was studied in three such cases using serially stored bone marrow. At diagnosis, a major MPL515 mutant clone was accompanied by a minor JAK2V617F clone in all three instances. At 25 time points over a period of 4-8 years, allele burden fluctuated but remained high for MPLW515L/K and low for JAK2V617F. We conclude that MPLW515L/K and JAK2V617F are both early events in MMM and allele burden, rather than the mere presence of these mutations, might be relevant to phenotypic variation in myeloproliferative disorders.

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

    Science.gov (United States)

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

    2016-12-01

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

  4. Spectrum of Phenylalanine Hydroxylase Gene Mutations in Hamadan and Lorestan Provinces of Iran and Their Associations with Variable Number of Tandem Repeat Alleles

    Directory of Open Access Journals (Sweden)

    Reza Alibakhshi

    2018-05-01

    Full Text Available Phenylketonuria (PKU is one of the most common known inherited metabolic diseases. The present study aimed to investigate the status of molecular defects in phenylalanine hydroxylase (PAH gene in western Iranian PKU patients (predominantly from Kermanshah, Hamadan, and Lorestan provinces during 2014-2016. Additionally, the results were compared with similar studies in Iran. Nucleotide sequence analysis of all 13 exons and their flanking intronic regions of the PAH gene was performed in 18 western Iranian PKU patients. Moreover, a variable number of tandem repeat (VNTR located in the PAH gene was studied. The results revealed a mutational spectrum encompassing 11 distinct mutations distributed along the PAH gene sequence on 34 of the 36 mutant alleles (diagnostic efficiency of 94.4%. Also, four PAH VNTR alleles (with repeats of 3, 7, 8 and 9 were detected. The three most frequent mutations were IVS9+5G>A, IVS7-5T>C, and p.P281L with the frequency of 27.8%, 11%, and 11%, respectively. The results showed that there is not only a consanguineous relation, but also a difference in PAH characters of mutations between Kermanshah and the other two parts of western Iran (Hamadan and Lorestan. Also, it seems that the spectrum of mutations in western Iran is relatively distinct from other parts of the country, suggesting that this region might be a special PAH gene distribution region. Moreover, our findings can be useful in the identification of genotype to phenotype relationship in patients, and provide future abilities for confirmatory diagnostic testing, prognosis, and predict the severity of PKU patients.

  5. Spectrum of Phenylalanine Hydroxylase Gene Mutations in Hamadan and Lorestan Provinces of Iran and Their Associations with Variable Number of Tandem Repeat Alleles.

    Science.gov (United States)

    Alibakhshi, Reza; Moradi, Keivan; Biglari, Mostafa; Shafieenia, Samaneh

    2018-05-01

    Phenylketonuria (PKU) is one of the most common known inherited metabolic diseases. The present study aimed to investigate the status of molecular defects in phenylalanine hydroxylase ( PAH ) gene in western Iranian PKU patients (predominantly from Kermanshah, Hamadan, and Lorestan provinces) during 2014-2016. Additionally, the results were compared with similar studies in Iran. Nucleotide sequence analysis of all 13 exons and their flanking intronic regions of the PAH gene was performed in 18 western Iranian PKU patients. Moreover, a variable number of tandem repeat (VNTR) located in the PAH gene was studied. The results revealed a mutational spectrum encompassing 11 distinct mutations distributed along the PAH gene sequence on 34 of the 36 mutant alleles (diagnostic efficiency of 94.4%). Also, four PAH VNTR alleles (with repeats of 3, 7, 8 and 9) were detected. The three most frequent mutations were IVS9+5G>A, IVS7-5T>C, and p.P281L with the frequency of 27.8%, 11%, and 11%, respectively. The results showed that there is not only a consanguineous relation, but also a difference in PAH characters of mutations between Kermanshah and the other two parts of western Iran (Hamadan and Lorestan). Also, it seems that the spectrum of mutations in western Iran is relatively distinct from other parts of the country, suggesting that this region might be a special PAH gene distribution region. Moreover, our findings can be useful in the identification of genotype to phenotype relationship in patients, and provide future abilities for confirmatory diagnostic testing, prognosis, and predict the severity of PKU patients.

  6. In Vivo-Selected Compensatory Mutations Restore the Fitness Cost of Mosaic penA Alleles That Confer Ceftriaxone Resistance in Neisseria gonorrhoeae.

    Science.gov (United States)

    Vincent, Leah R; Kerr, Samuel R; Tan, Yang; Tomberg, Joshua; Raterman, Erica L; Dunning Hotopp, Julie C; Unemo, Magnus; Nicholas, Robert A; Jerse, Ann E

    2018-04-03

    Resistance to ceftriaxone in Neisseria gonorrhoeae is mainly conferred by mosaic penA alleles that encode penicillin-binding protein 2 (PBP2) variants with markedly lower rates of acylation by ceftriaxone. To assess the impact of these mosaic penA alleles on gonococcal fitness, we introduced the mosaic penA alleles from two ceftriaxone-resistant (Cro r ) clinical isolates (H041 and F89) into a Cro s strain (FA19) by allelic exchange and showed that the resultant Cro r mutants were significantly outcompeted by the Cro s parent strain in vitro and in a murine infection model. Four Cro r compensatory mutants of FA19 penA41 were isolated independently from mice that outcompeted the parent strain both in vitro and in vivo One of these compensatory mutants (LV41C) displayed a unique growth profile, with rapid log growth followed by a sharp plateau/gradual decline at stationary phase. Genome sequencing of LV41C revealed a mutation (G348D) in the acnB gene encoding the bifunctional aconitate hydratase 2/2 methylisocitrate dehydratase. Introduction of the acnB G348D allele into FA19 penA41 conferred both a growth profile that phenocopied that of LV41C and a fitness advantage, although not as strongly as that exhibited by the original compensatory mutant, suggesting the existence of additional compensatory mutations. The mutant aconitase appears to be a functional knockout with lower activity and expression than wild-type aconitase. Transcriptome sequencing (RNA-seq) analysis of FA19 penA41 acnB G348D revealed a large set of upregulated genes involved in carbon and energy metabolism. We conclude that compensatory mutations can be selected in Cro r gonococcal strains that increase metabolism to ameliorate their fitness deficit. IMPORTANCE The emergence of ceftriaxone-resistant (Cro r ) Neisseria gonorrhoeae has led to the looming threat of untreatable gonorrhea. Whether Cro resistance is likely to spread can be predicted from studies that compare the relative fitnesses of

  7. Allelic mutations of KITLG, encoding KIT ligand, cause asymmetric and unilateral hearing loss and Waardenburg syndrome type 2

    NARCIS (Netherlands)

    Zazo Seco, C. (Celia); Serrão De Castro, L. (Luciana); J.W.I. van Nierop; Morín, M. (Matías); S.N. Jhangiani (Shalini N.); E.J.J. Verver (Eva J. J.); M. Schraders (Margit); Maiwald, N. (Nadine); Wesdorp, M. (Mieke); H. Venselaar (Hanka); L. Spruijt (Liesbeth); Oostrik, J. (Jaap); J. Schoots (Jeroen); J. van Reeuwijk (Jeroen); Lelieveld, S.H. (Stefan H.); P.L.M. Huygen (Patrick); Insenser, M. (María); R.J. Admiraal (Ronald); R.J.E. Pennings (Ronald J.E.); E.H. Hoefsloot (Lies); A. Arias-Vásquez (Alejandro); J. de Ligt (Joep); H.G. Yntema; Jansen, J.H. (Joop H.); D. Muzny (Donna); G. Huls (Gerwin); M.M. van Rossum (Michelle); J.R. Lupski (James R.); Moreno-Pelayo, M.A. (Miguel Angel); H.P.M. Kunst (Henricus P.M.); H. Kremer (Hannie)

    2015-01-01

    textabstractLinkage analysis combined with whole-exome sequencing in a large family with congenital and stable non-syndromic unilateral and asymmetric hearing loss (NS-UHL/AHL) revealed a heterozygous truncating mutation, c.286-303delinsT (p.Ser96Ter), in KITLG. This mutation co-segregated with

  8. Allelic Mutations of KITLG, Encoding KIT Ligand, Cause Asymmetric and Unilateral Hearing Loss and Waardenburg Syndrome Type 2

    NARCIS (Netherlands)

    Zazo Seco, C.; Castro, L.S. de; Nierop, J.W. van; Morin, M.; Jhangiani, S.; Verver, E.J.; Schraders, M.; Maiwald, N.; Wesdorp, F.M.; Venselaar, H.; Spruijt, L.; Oostrik, J.; Schoots, J.; Reeuwijk, J. van; Lelieveld, S.H.; Huygen, P.L.M.; Insenser, M.; Admiraal, R.J.C.; Pennings, R.J.E.; Hoefsloot, L.H.; Arias Vasquez, A.; Ligt, J. de; Yntema, H.G.; Jansen, J.H.; Muzny, D.M.; Huls, G.A.; Rossum, M.M. van; Lupski, J.R.; Moreno-Pelayo, M.A.; Kunst, H.P.M.; Kremer, H.

    2015-01-01

    Linkage analysis combined with whole-exome sequencing in a large family with congenital and stable non-syndromic unilateral and asymmetric hearing loss (NS-UHL/AHL) revealed a heterozygous truncating mutation, c.286_303delinsT (p.Ser96Ter), in KITLG. This mutation co-segregated with NS-UHL/AHL as a

  9. Dominant versus recessive traits conveyed by allelic mutations - to what extent is nonsense-mediated decay involved?

    NARCIS (Netherlands)

    Ben-Shachar, S.; Khajavi, M.; Withers, M.A.; Shaw, C.A.; Bokhoven, J.H.L.M. van; Brunner, H.G.; Lupski, J.R.

    2009-01-01

    Mutations in ROR2, encoding a receptor tyrosine kinase, can cause autosomal recessive Robinow syndrome (RRS), a severe skeletal dysplasia with limb shortening, brachydactyly, and a dysmorphic facial appearance. Other mutations in ROR2 result in the autosomal dominant disease, brachydactyly type B

  10. High prevalence of arterial thrombosis in JAK2 mutated essential thrombocythaemia: independence of the V617F allele burden

    DEFF Research Database (Denmark)

    Larsen, Thomas Stauffer; Pallisgaard, Niels; Møller, Michael Boe

    2008-01-01

    Approximately half of the patients with essential thrombocythaemia (ET) harbor the JAK2 V617F mutation. Despite a phenotypic mimicry of JAK2 V617F positive ET and polycythaemia vera (PV), the data on thromboembolic risk and correlation to JAK2 mutation status are ambiguous. On a strictly WHO defi...

  11. Exome sequencing identifies rare deleterious mutations in DNA repair genes FANCC and BLM as potential breast cancer susceptibility alleles.

    Directory of Open Access Journals (Sweden)

    Ella R Thompson

    2012-09-01

    Full Text Available Despite intensive efforts using linkage and candidate gene approaches, the genetic etiology for the majority of families with a multi-generational breast cancer predisposition is unknown. In this study, we used whole-exome sequencing of thirty-three individuals from 15 breast cancer families to identify potential predisposing genes. Our analysis identified families with heterozygous, deleterious mutations in the DNA repair genes FANCC and BLM, which are responsible for the autosomal recessive disorders Fanconi Anemia and Bloom syndrome. In total, screening of all exons in these genes in 438 breast cancer families identified three with truncating mutations in FANCC and two with truncating mutations in BLM. Additional screening of FANCC mutation hotspot exons identified one pathogenic mutation among an additional 957 breast cancer families. Importantly, none of the deleterious mutations were identified among 464 healthy controls and are not reported in the 1,000 Genomes data. Given the rarity of Fanconi Anemia and Bloom syndrome disorders among Caucasian populations, the finding of multiple deleterious mutations in these critical DNA repair genes among high-risk breast cancer families is intriguing and suggestive of a predisposing role. Our data demonstrate the utility of intra-family exome-sequencing approaches to uncover cancer predisposition genes, but highlight the major challenge of definitively validating candidates where the incidence of sporadic disease is high, germline mutations are not fully penetrant, and individual predisposition genes may only account for a tiny proportion of breast cancer families.

  12. Identification of colorectal cancer patients with tumors carrying the TP53 mutation on the codon 72 proline allele that benefited most from 5-fluorouracil (5-FU) based postoperative chemotherapy

    International Nuclear Information System (INIS)

    Godai, Ten-i; Sakuma, Yuji; Tsuchiya, Eiju; Kameda, Yoichi; Akaike, Makoto; Miyagi, Yohei; Suda, Tetsuji; Sugano, Nobuhiro; Tsuchida, Kazuhito; Shiozawa, Manabu; Sekiguchi, Hironobu; Sekiyama, Akiko; Yoshihara, Mitsuyo; Matsukuma, Shoichi

    2009-01-01

    Although postoperative chemotherapy is widely accepted as the standard modality for Dukes' stage C or earlier stage colorectal cancer (CRC) patients, biomarkers to predict those who may benefit from the therapy have not been identified. Previous in vitro and clinical investigations reported that CRC patients with wild-type p53 gene (TP53)-tumors benefit from 5-fluorouracil (5-FU) based chemotherapy, while those with mutated TP53-tumors do not. However, these studies evaluated the mutation-status of TP53 by immunohistochemistry with or without single-strand conformation polymorphism, and the mutation frequency was different from study to study. In addition, the polymorphic status at p53 codon 72, which results in arginine or proline residues (R72P) and is thought to influence the function of the protein significantly, was not examined. To evaluate the significance of the TP53 mutation as a molecular marker to predict the prognosis of CRC patients, especially those who received postoperative chemotherapy, we examined the mutation by direct sequencing from fresh CRC tumors and evaluated the R72P polymorphism of the mutated TP53 by a combined mutant allele- and polymorphic allele-specific polymerase chain reaction (PCR). The TP53 mutation occurred in 147 (70%) of 211 Japanese CRC tumors. The mutation was observed in 93 (63%) tumors on the R72 allele and in 54 (37%) tumors on the P72 allele. Although the alterations to TP53 have no prognostic significance for CRC patients overall, we found that Dukes' stage C CRC patients who did not receive postoperative chemotherapy and carried the mutated TP53-R72 showed significantly longer survival times than those with the mutated TP53-P72 when evaluated by overall survival (p = 0.012). Using a combined mutant allele- and polymorphic allele-specific PCR, we defined the codon 72 polymorphic status of the TP53 mutated allele in Japanese CRC patients. We raised a possibility that Dukes' stage C colorectal cancer

  13. One adenosine deaminase allele in a patient with severe combined immunodeficiency contains a point mutation abolishing enzyme activity.

    OpenAIRE

    Valerio, D; Dekker, B M; Duyvesteyn, M G; van der Voorn, L; Berkvens, T M; van Ormondt, H; van der Eb, A J

    1986-01-01

    We have cloned and sequenced an adenosine deaminase (ADA) gene from a patient with severe combined immunodeficiency (SCID) caused by inherited ADA deficiency. Two point mutations were found, resulting in amino acid substitutions at positions 80 (Lys to Arg) and 304 (Leu to Arg) of the protein. Hybridization experiments with synthetic oligonucleotide probes showed that the determined mutations are present in both DNA and RNA from the ADA-SCID patient. In addition, wild-type sequences could be ...

  14. Usher syndrome type 1 due to missense mutations on both CDH23 alleles: investigation of mRNA splicing.

    Science.gov (United States)

    Becirovic, Elvir; Ebermann, Inga; Nagy, Ditta; Zrenner, Eberhart; Seeliger, Mathias Wolfgang; Bolz, Hanno Jörn

    2008-03-01

    Usher syndrome (USH) is an autosomal recessive condition characterized by sensorineural hearing loss, vestibular dysfunction, and visual impairment due to retinitis pigmentosa. Truncating mutations in the cadherin-23 gene (CDH23) result in Usher syndrome type 1D (USH1D), whereas missense mutations affecting strongly conserved motifs of the CDH23 protein cause non-syndromic deafness (DFNB12). Four missense mutations constitute an exception from this genotype-phenotype correlation: they have been described in USH1 patients in homozygous state. Using a minigene assay, we have investigated these changes (c.1450G>C, p.A484P; c.3625A>G, p.T1209A; c.4520G>A, p.R1507Q; and c.5237G>A, p.R1746Q) for a possible impact on mRNA splicing which could explain the syndromic phenotype. While in silico analysis suggested impairment of splicing in all four cases, we found aberrant splicing for only one mutation, p.R1746Q. However, splicing was normal in case of p.A484P, p.T1209A and p.R1507Q. These three latter CDH23 missense mutations could interfere with functions of both, the auditory and the visual system. Alternatively, they could represent rare non-pathogenic polymorphisms.

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

    Directory of Open Access Journals (Sweden)

    E. L. Dadali

    2016-01-01

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

  16. Allelic Mutations of KITLG, Encoding KIT Ligand, Cause Asymmetric and Unilateral Hearing Loss and Waardenburg Syndrome Type 2.

    Science.gov (United States)

    Zazo Seco, Celia; Serrão de Castro, Luciana; van Nierop, Josephine W; Morín, Matías; Jhangiani, Shalini; Verver, Eva J J; Schraders, Margit; Maiwald, Nadine; Wesdorp, Mieke; Venselaar, Hanka; Spruijt, Liesbeth; Oostrik, Jaap; Schoots, Jeroen; van Reeuwijk, Jeroen; Lelieveld, Stefan H; Huygen, Patrick L M; Insenser, María; Admiraal, Ronald J C; Pennings, Ronald J E; Hoefsloot, Lies H; Arias-Vásquez, Alejandro; de Ligt, Joep; Yntema, Helger G; Jansen, Joop H; Muzny, Donna M; Huls, Gerwin; van Rossum, Michelle M; Lupski, James R; Moreno-Pelayo, Miguel Angel; Kunst, Henricus P M; Kremer, Hannie

    2015-11-05

    Linkage analysis combined with whole-exome sequencing in a large family with congenital and stable non-syndromic unilateral and asymmetric hearing loss (NS-UHL/AHL) revealed a heterozygous truncating mutation, c.286_303delinsT (p.Ser96Ter), in KITLG. This mutation co-segregated with NS-UHL/AHL as a dominant trait with reduced penetrance. By screening a panel of probands with NS-UHL/AHL, we found an additional mutation, c.200_202del (p.His67_Cys68delinsArg). In vitro studies revealed that the p.His67_Cys68delinsArg transmembrane isoform of KITLG is not detectable at the cell membrane, supporting pathogenicity. KITLG encodes a ligand for the KIT receptor. Also, KITLG-KIT signaling and MITF are suggested to mutually interact in melanocyte development. Because mutations in MITF are causative of Waardenburg syndrome type 2 (WS2), we screened KITLG in suspected WS2-affected probands. A heterozygous missense mutation, c.310C>G (p.Leu104Val), that segregated with WS2 was identified in a small family. In vitro studies revealed that the p.Leu104Val transmembrane isoform of KITLG is located at the cell membrane, as is wild-type KITLG. However, in culture media of transfected cells, the p.Leu104Val soluble isoform of KITLG was reduced, and no soluble p.His67_Cys68delinsArg and p.Ser96Ter KITLG could be detected. These data suggest that mutations in KITLG associated with NS-UHL/AHL have a loss-of-function effect. We speculate that the mechanism of the mutation underlying WS2 and leading to membrane incorporation and reduced secretion of KITLG occurs via a dominant-negative or gain-of-function effect. Our study unveils different phenotypes associated with KITLG, previously associated with pigmentation abnormalities, and will thereby improve the genetic counseling given to individuals with KITLG variants. Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  17. Comparison of allelic discrimination by dHPLC, HRM, and TaqMan in the detection of BRAF mutation V600E.

    Science.gov (United States)

    Carbonell, Pablo; Turpin, María C; Torres-Moreno, Daniel; Molina-Martínez, Irene; García-Solano, José; Perez-Guillermo, Miguel; Conesa-Zamora, Pablo

    2011-09-01

    The V600E mutation in the BRAF oncogene is associated with colorectal carcinomas, with mismatch-repair deficiency and, recently, with nonresponse to epidermal growth factor receptor inhibitor therapy. The use of reliable techniques for its detection is important. The aim of our study was to compare the performance characteristics in V600E detection of denaturing high-performance liquid chromatography (dHPLC) and high-resolution melting (HRM) with TaqMan allelic discrimination as well as direct-sequencing methods in a series of 195 colorectal paraffin-embedded specimens up to the age of 15 years. The effectiveness for obtaining results on mutation status was best using TaqMan (96.9%), followed by dHPLC (93.3%), HRM (88.7%), and sequencing (88.2%). In general, TaqMan was best for analyzing older tissues, whereas sequencing was the least efficient. Heterozygotic V600E was detected in 11.6%, 9.9%, 11.6%, and 9.9% of tissues using TaqMan, dHPLC, HRM, and sequencing, respectively. Result concordances between dHPLC and TaqMan or sequencing were excellent (κ = 0.9411 and κ = 0.8988, respectively); for HRM, the concordances were good (κ = 0.7973 and κ = 0.7488, respectively). By using DNA dilutions from tumor tissue, a minimum of 10% of V600E harboring cancer content was required for the analysis by dHPLC and HRM. dHPLC could detect four non-V600E mutations, whereas HRM detected one. Our results indicate that dHPLC and HRM are techniques that can be reliably used for the detection of the BRAFV600E mutation in archival paraffin-embedded tissues. Copyright © 2011 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  18. A 7666-bp genomic deletion is frequent in Chinese Han deaf patients with non-syndromic enlarged vestibular aqueduct but without bi-allelic SLC26A4 mutations.

    Science.gov (United States)

    Pang, Xiuhong; Chai, Yongchuan; He, Longxia; Chen, Penghui; Wang, Xiaowen; Li, Lei; Jia, Huan; Wu, Hao; Yang, Tao

    2015-12-01

    To investigate the genetic cause of the patients with non-syndromic enlarged vestibular aqueduct (EVA) but without bi-allelic SLC26A4 mutations. Presence of a homozygous genomic deletion was detected in a Chinese Han deaf patient (D1467-1) who failed to amplify the first three exons of SLC26A4. The breakpoints of the deletion were fine-mapped and revealed by PCR amplification and sequencing. This deletion was subsequently screened in 22 Chinese Han EVA probands with mono-allelic SLC26A4 mutations. The possible founder effect of the newly identified genomic deletion was evaluated by haplotype analysis. A homozygous c.-2071_307+3801del7666 deletion of SLC26A4 was identified in patient D1467-1. This novel genomic deletion was subsequently identified in 18% (4/22) of the Chinese Han EVA probands with mono-allelic SLC26A4 mutations. Haplotype analysis showed that this genomic deletion is likely a founder mutation in Chinese Hans. Our results suggested that the cryptic c.-2071_307+3801del7666 deletion of SLC26A4 is relatively frequent in Chinese Han non-syndromic EVA patients without bi-allelic SLC26A4 mutations. Screening of this genomic deletion should be incorporated into the routine DNA testing of SLC26A4 in Chinese Hans. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Evaluation of the correlation between KRAS mutated allele frequency and pathologist tumorous nuclei percentage assessment in colorectal cancer suggests a role for zygosity status.

    Science.gov (United States)

    Libbrecht, Louis; Baldin, Pamela; Dekairelle, Anne-France; Jouret-Mourin, Anne

    2018-04-27

    Evaluation of molecular tumour heterogeneity relies on the tumorous nuclei percentage (TNP) assessment by a pathologist, which has been criticised for being inaccurate and suffering from interobserver variability. Based on the 'Big Bang theory' which states that KRAS mutation in colorectal cancer is mostly homogeneous, we investigated this issue by performing a critical analysis of the correlation of the KRAS mutant allele fraction with the TNP in 99 colorectal tumour samples with a positive KRAS mutation status as determined by next-generation sequencing. Our results yield indirect evidence that the KRAS zygosity status influences the correlation between these parameters and we show that a well-trained pathologist is indeed capable of accurately assessing TNP. Our findings indicate that tumour zygosity, a feature which has largely been neglected until now, should be taken into account in future studies on (colorectal) molecular tumour heterogeneity. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  20. The neurological mouse mutations jittery and hesitant are allelic and map to the region of mouse chromosome 10 homologous to 19p13.3

    Energy Technology Data Exchange (ETDEWEB)

    Kapfhamer, D.; Sufalko, D.; Warren, S. [Univ. of Michigan, Ann Arbor, MI (United States)] [and others

    1996-08-01

    Jittery (ji) is a recessive mouse mutation on Chromosome 10 characterized by progressive ataxic gait, dystonic movements, spontaneus seizures, and death by dehydration/starvation before fertility. Recently, a viable neurological recessive mutation, hesitant, was discovered. It is characterized by hesitant, uncoordinated movements, exaggerated stepping of the hind limbs, and reduced fertility in males. In a complementation test and by genetic mapping we have shown here that hesitant and jittery are allelic. Using several large intersubspecific backcrosses and intercrosses we have genetically mapped ji near the marker Amh and microsatellite markers D10Mit7, D10Mit21, and D10Mit23. The linked region of mouse Chromosome 10 is homologous to human 19p13.3, to which several human ataxia loci have recently been mapped. By excluding genes that map to human 21q22.3 (Pfkl) and 12q23 (Nfyb), we conclude that jittery is not likely to be a genetic mouse model for human Unverricht-Lundborg progressive myoclonus epilepsy (EPM1) on 21q22.3 nor for spinocerebellar ataxia II (SCA2) on 12q22-q24. The closely linked markers presented here will facilitate positional cloning of the ji gene. 31 refs., 2 figs.

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

    Directory of Open Access Journals (Sweden)

    Thatiane Yoshie Kanazawa

    2014-12-01

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

  2. Somatic mutations, allele loss, and DNA methylation of the Cub and Sushi Multiple Domains 1 (CSMD1 gene reveals association with early age of diagnosis in colorectal cancer patients.

    Directory of Open Access Journals (Sweden)

    Austin Y Shull

    Full Text Available The Cub and Sushi Multiple Domains 1 (CSMD1 gene, located on the short arm of chromosome 8, codes for a type I transmembrane protein whose function is currently unknown. CSMD1 expression is frequently lost in many epithelial cancers. Our goal was to characterize the relationships between CSMD1 somatic mutations, allele imbalance, DNA methylation, and the clinical characteristics in colorectal cancer patients.We sequenced the CSMD1 coding regions in 54 colorectal tumors using the 454FLX pyrosequencing platform to interrogate 72 amplicons covering the entire coding sequence. We used heterozygous SNP allele ratios at multiple CSMD1 loci to determine allelic balance and infer loss of heterozygosity. Finally, we performed methylation-specific PCR on 76 colorectal tumors to determine DNA methylation status for CSMD1 and known methylation targets ALX4, RUNX3, NEUROG1, and CDKN2A.Using 454FLX sequencing and confirming with Sanger sequencing, 16 CSMD1 somatic mutations were identified in 6 of the 54 colorectal tumors (11%. The nonsynonymous to synonymous mutation ratio of the 16 somatic mutations was 15:1, a ratio significantly higher than the expected 2:1 ratio (p = 0.014. This ratio indicates a presence of positive selection for mutations in the CSMD1 protein sequence. CSMD1 allelic imbalance was present in 19 of 37 informative cases (56%. Patients with allelic imbalance and CSMD1 mutations were significantly younger (average age, 41 years than those without somatic mutations (average age, 68 years. The majority of tumors were methylated at one or more CpG loci within the CSMD1 coding sequence, and CSMD1 methylation significantly correlated with two known methylation targets ALX4 and RUNX3. C:G>T:A substitutions were significantly overrepresented (47%, suggesting extensive cytosine methylation predisposing to somatic mutations.Deep amplicon sequencing and methylation-specific PCR reveal that CSMD1 alterations can correlate with earlier clinical

  3. Identification of TCT, a novel knockdown resistance allele mutation and analysis of resistance detection methods in the voltage-gated Na⁺ channel of Culex pipiens pallens from Shandong Province, China.

    Science.gov (United States)

    Liu, Hong-Mei; Cheng, Peng; Huang, Xiaodan; Dai, Yu-Hua; Wang, Hai-Fang; Liu, Li-Juan; Zhao, Yu-Qiang; Wang, Huai-Wei; Gong, Mao-Qing

    2013-02-01

    The present study aimed to investigate deltamethrin resistance in Culex pipiens pallens (C. pipiens pallens) mosquitoes and its correlation with knockdown resistance (kdr) mutations. In addition, mosquito‑resistance testing methods were analyzed. Using specific primers in polymerase chain reaction (PCR) and allele-specific (AS)-PCR, kdr gene sequences isolated from wild C. pipiens pallens mosquitoes were sequenced. Linear regression analysis was used to determine the correlation between the mutations and deltamethrin resistance. A kdr allelic gene was cloned and sequenced. Analysis of the DNA sequences revealed the presence of two point mutations at the L1014 residue in the IIS6 transmembrane segment of the voltage‑gated sodium channel (VGSC): L1014F, TTA→TTT, replacing a leucine (L) with a phenylalanine (F); L1014S, TTA→TCA, replacing leucine (L) with serine (S). Two alternative kdr-like mutations, L1014F and L1014S, were identified to be positively correlated with the deltamethrin-resistant phenotype. In addition a novel mutation, TCT, was identified in the VGSC of C. pipiens pallens. PCR and AS-PCR yielded consistent results with respect to mosquito resistance. However, the detection rate of PCR was higher than that of AS-PCR. Further studies are required to determine the specific resistance mechanism. PCR and AS-PCR demonstrated suitability for mosquito resistance field tests, however, the former method may be superior to the latter.

  4. N1303K (c.3909C>G) Mutation and Splicing: Implication of Its c.[744-33GATT(6); 869+11C>T] Complex Allele in CFTR Exon 7 Aberrant Splicing

    Science.gov (United States)

    Farhat, Raëd; Puissesseau, Géraldine; El-Seedy, Ayman; Pasquet, Marie-Claude; Adolphe, Catherine; Corbani, Sandra; Megarbané, André; Kitzis, Alain; Ladeveze, Véronique

    2015-01-01

    Cystic Fibrosis is the most common recessive autosomal rare disease found in Caucasians. It is caused by mutations on the Cystic Fibrosis Transmembrane Conductance Regulator gene (CFTR) that encodes a protein located on the apical membrane of epithelial cells. c.3909C>G (p.Asn1303Lys, old nomenclature: N1303K) is one of the most common worldwide mutations. This mutation has been found at high frequencies in the Mediterranean countries with the highest frequency in the Lebanese population. Therefore, on the genetic level, we conducted a complete CFTR gene screening on c.3909C>G Lebanese patients. The complex allele c.[744-33GATT(6); 869+11C>T] was always associated with the c.3909C>G mutation in cis in the Lebanese population. In cellulo splicing studies, realized by hybrid minigene constructs, revealed no impact of the c.3909C>G mutation on the splicing process, whereas the associated complex allele induces minor exon skipping. PMID:26075213

  5. Establishment of real time allele specific locked nucleic acid quantitative PCR for detection of HBV YIDD (ATT mutation and evaluation of its application.

    Directory of Open Access Journals (Sweden)

    Yongbin Zeng

    Full Text Available BACKGROUND: Long-term use of nucleos(tide analogues can increase risk of HBV drug-resistance mutations. The rtM204I (ATT coding for isoleucine is one of the most important resistance mutation sites. Establishing a simple, rapid, reliable and highly sensitive assay to detect the resistant mutants as early as possible is of great clinical significance. METHODS: Recombinant plasmids for HBV YMDD (tyrosine-methionine-aspartate-aspartate and YIDD (tyrosine-isoleucine-aspartate-aspartate were constructed by TA cloning. Real time allele specific locked nucleic acid quantitative PCR (RT-AS-LNA-qPCR with SYBR Green I was established by LNA-modified primers and evaluated with standard recombinant plasmids, clinical templates (the clinical wild type and mutant HBV DNA mixture and 102 serum samples from nucleos(tide analogues-experienced patients. The serum samples from a chronic hepatitis B (CHB patient firstly received LMV mono therapy and then switched to LMV + ADV combined therapy were also dynamically analyzed for 10 times. RESULTS: The linear range of the assay was between 1×10(9 copies/μl and 1 × 10(2 copies/μl. The low detection limit was 1 × 10(1 copies/μl. Sensitivity of the assay were 10(-6, 10(-4 and 10(-2 in the wild-type background of 1 × 10(9 copies/μl, 1 × 10(7 copies/μl and 1 × 10(5 copies/μl, respectively. The sensitivity of the assay in detection of clinical samples was 0.03%. The complete coincidence rate between RT-AS-LNA-qPCR and direct sequencing was 91.2% (93/102, partial coincidence rate was 8.8% (9/102, and no complete discordance was observed. The two assays showed a high concordance (Kappa = 0.676, P = 0.000. Minor variants can be detected 18 weeks earlier than the rebound of HBV DNA load and alanine aminotransferase level. CONCLUSIONS: A rapid, cost-effective, high sensitive, specific and reliable method of RT-AS-LNA-qPCR with SYBR Green I for early and absolute quantification of HBV YIDD (ATT coding for isoleucine

  6. Validation of a Multiplex Allele-Specific Polymerase Chain Reaction Assay for Detection of KRAS Gene Mutations in Formalin-Fixed, Paraffin-Embedded Tissues from Colorectal Cancer Patients.

    Directory of Open Access Journals (Sweden)

    Sirirat Seekhuntod

    Full Text Available Patients with KRAS mutations do not respond to epidermal growth factor receptor (EGFR inhibitors and fail to benefit from adjuvant chemotherapy. Mutation analysis of KRAS is needed before starting treatment with monoclonal anti-EGFR antibodies in patients with metastatic colorectal cancer (mCRC. The objective of this study is to develop a multiplex allele-specific PCR (MAS-PCR assay to detect KRAS mutations.We developed a single-tube MAS-PCR assay for the detection of seven KRAS mutations (G12D, G12A, G12R, G12C, G12S, G12V, and G13D. We performed MAS-PCR assay analysis for KRAS on DNA isolated from 270 formalin-fixed paraffin-embedded (FFPE colorectal cancer tissues. Sequences of all 270 samples were determined by pyrosequencing. Seven known point-mutation DNA samples diluted with wild-type DNA were assayed to determine the limitation of detection and reproducibility of the MAS-PCR assay.Overall, the results of MAS-PCR assay were in good concordance with pyrosequencing, and only seven discordant samples were found. The MAS-PCR assay reproducibly detected 1 to 2% mutant alleles. The most common mutations were G13D in codon 13 (49.17%, G12D (25.83% and G12V (12.50% in codon 12.The MAS-PCR assay provides a rapid, cost-effective, and reliable diagnostic tool for accurate detection of KRAS mutations in routine FFPE colorectal cancer tissues.

  7. Identification of a c.544C>T mutation in WDR34 as a deleterious recessive allele of short rib-polydactyly syndrome

    Directory of Open Access Journals (Sweden)

    Shu-Han You

    2017-12-01

    Conclusion: This study was the first to identify c.544C > T [p.Arg182Trp] mutation in WDR34 in a patient with SRPS. According to the database, the homozygous mutation of c.544C > T in WDR34 was deleterious and the prevalence of heterozygous mutation was relatively higher in Asian population. More studies of this mutation in patients with SRPS are required.

  8. Two mutations in the same low-density lipoprotein receptor allele act in synergy to reduce receptor function in heterozygous familial hypercholesterolemia

    DEFF Research Database (Denmark)

    Jensen, H K; Jensen, T G; Faergeman, O

    1997-01-01

    Mutations in genes are not necessarily pathogenic. Expression of mutant genes in cells can therefore be required to demonstrate that mutations in fact disturb protein function. This applies especially to missense mutations, which cause an amino acid to be replaced by another amino acid. In the pr...

  9. Development of an allele-specific, loop-mediated, isothermal amplification method (AS-LAMP to detect the L1014F kdr-w mutation in Anopheles gambiae s. l.

    Directory of Open Access Journals (Sweden)

    Badolo Athanase

    2012-07-01

    Full Text Available Abstract Background Malaria control relies heavily on treated bed nets and indoor residual spraying with pyrethroid insecticides. Unfortunately, the resistance to pyrethroid insecticides, mainly due to the kdr mutation, is spreading in the main malaria vector Anopheles gambiae s.l., decreasing the insecticides’ efficacy. To manage the insecticide resistance rapidly and flexibly, simple and effective tools for the early detection of resistant mosquitoes are needed. This study aimed to develop an allele-specific, loop-mediated, isothermal amplification (AS-LAMP method to detect the West African-type kdr mutation (kdr-w; L1014F in field-collected mosquitoes. Methods DNA fragments of the wild-type and the mutated kdr gene were used to select the primers and develop the method. The primers were designed with the mutation at the 5’ end of the backward inner primer (BIP. The AS-LAMP method was compared to the AS-PCR method using the genomic DNA of 120 field-collected mosquitoes. Results The AS-LAMP method could discriminate between the wild-type homozygote, the heterozygote, and the kdr-w homozygote within 75 min. The AS-LAMP method has the advantage of being faster and at least as sensitive and specific as the AS-PCR method. Conclusions The AS-LAMP method can be used to detect the kdr mutation for quick decision-making, even in less well-equipped laboratories.

  10. Common breast cancer susceptibility alleles are associated with tumor subtypes in BRCA1 and BRCA2 mutation carriers: results from the Consortium of Investigators of Modifiers of BRCA1/2

    DEFF Research Database (Denmark)

    Mulligan, Anna Marie; Couch, Fergus J; Barrowdale, Daniel

    2011-01-01

    BRCA1 carriers, SNP rs2981582 (FGFR2) exhibited the biggest difference based on ER status (per-allele HR for ER-positive=1.35, 95%CI:1.17-1.56 vs HR=0.91, 95%CI:0.85-0.98 for ER-negative, P-heterogeneity=6.5e-6). In contrast, SNP rs2046210 at 6q25.1 near ESR1 was primarily associated with ER...... subtypes. As more risk modifying variants are identified, incorporating these associations into breast cancer subtype-specific risk models may improve clinical management for mutation carriers....

  11. A Nonsense Mutation in FAM161A Is a Recurrent Founder Allele in Dutch and Belgian Individuals With Autosomal Recessive Retinitis Pigmentosa

    NARCIS (Netherlands)

    Van Schil, Kristof; Klevering, B. Jeroen; Leroy, Bart P.; Pott, Jan Willem R.; Bandah-Rozenfeld, Dikla; Zonneveld-Vrieling, Marijke N.; Sharon, Dror; den Hollander, Anneke I.; Cremers, Frans P. M.; De Baere, Elfride; Collin, Rob W. J.; van den Born, L. Ingeborgh

    PURPOSE. To identify mutations in FAM161A underlying autosomal recessive retinitis pigmentosa (arRP) in the Dutch and Belgian populations and to investigate whether common FAM161A-associated phenotypic features could be identified. METHODS. Homozygosity mapping, amplification-refractory mutation

  12. Associations of common breast cancer susceptibility alleles with risk of breast cancer subtypes in BRCA1 and BRCA2 mutation carriers

    NARCIS (Netherlands)

    K.B. Kuchenbaecker (Karoline); S.L. Neuhausen (Susan); M. Robson (Mark); D. Barrowdale (Daniel); L. McGuffog (Lesley); A.M. Mulligan (Anna Marie); I.L. Andrulis (Irene); A.B. Spurdle (Amanda); M.K. Schmidt (Marjanka); R.K. Schmutzler (Rita); C. Engel (Christoph); B. Wapenschmidt (Barbara); H. Nevanlinna (Heli); M. Thomassen (Mads); M.C. Southey (Melissa); P. Radice (Paolo); S.J. Ramus (Susan); S.M. Domchek (Susan); K.L. Nathanson (Katherine); A. Lee (Andrew); S. Healey (Sue); R. Nussbaum (Robert); R. Rebbeck (Timothy); B.K. Arun (Banu); M. James (Margaret); B.Y. Karlan (Beth); K.J. Lester (Kathryn); I. Cass (Ilana); M.B. Terry (Mary Beth); M.J. Daly (Mark); D. Goldgar (David); S.S. Buys (Saundra); R. Janavicius (Ramunas); L. Tihomirova (Laima); N. Tung (Nadine); C.M. Dorfling (Cecilia); E.J. van Rensburg (Elizabeth); L. Steele (Linda); T. v O Hansen (Thomas); B. Ejlertsen (Bent); A-M. Gerdes (Anne-Marie); F. Nielsen (Finn); J. Dennis (Joe); J.M. Cunningham (Julie); S. Hart (Stewart); S. Slager (Susan); A. Osorio (Ana); J. Benítez (Javier); M. Duran (Mercedes); J.N. Weitzel (Jeffrey); I. Tafur (Isaac); M. Hander (Mary); P. Peterlongo (Paolo); S. Manoukian (Siranoush); B. Peissel (Bernard); G. Roversi (Gaia); G. Scuvera (Giulietta); B. Bonnani (Bernardo); P. Mariani (Paolo); S. Volorio (Sara); R. Dolcetti (Riccardo); L. Varesco (Liliana); L. Papi (Laura); M.G. Tibiletti (Maria Grazia); G. Giannini (Giuseppe); F. Fostira (Florentia); I. Konstantopoulou (I.); J. Garber (Judy); U. Hamann (Ute); A. Donaldson (Alan); C. Brewer (Carole); C. Foo (Claire); D.G. Evans (Gareth); D. Frost (Debra); D. Eccles (Diana); F. Douglas (Fiona); A. Brady (A.); J. Cook (Jackie); M. Tischkowitz (Marc); L. Adlard; J. Barwell (Julian); K. Ong; L.J. Walker (Lisa); L. Izatt (Louise); L. Side (Lucy); M.J. Kennedy (John); M.T. Rogers (Mark); M.E. Porteous (Mary); P.J. Morrison (Patrick); R. Platte (Radka); R. Eeles (Ros); R. Davidson (Rosemarie); S. Hodgson (Shirley); S.D. Ellis (Steve); A.K. Godwin (Andrew); K. Rhiem (Kerstin); A. Meindl (Alfons); N. Ditsch (Nina); N. Arnold (Norbert); H. Plendl (Hansjoerg); D. Niederacher (Dieter); C. Sutter (Christian); D. Steinemann (Doris); N. Bogdanova-Markov (Nadja); K. Kast (Karin); R. Varon-Mateeva (Raymonda); S. Wang-Gohrke (Shan); P.A. Gehrig (Paola A.); B. Markiefka (Birgid); B. Buecher (Bruno); C. Lefol (Cédrick); D. Stoppa-Lyonnet (Dominique); E. Rouleau (Etienne); F. Prieur (Fabienne); F. Damiola (Francesca); L. Barjhoux (Laure); L. Faivre (Laurence); M. Longy (Michel); N. Sevenet (Nicolas); O. Sinilnikova (Olga); S. Mazoyer (Sylvie); V. Bonadona (Valérie); V. Caux-Moncoutier (Virginie); C. Isaacs (Claudine); T. Van Maerken (Tom); K.B.M. Claes (Kathleen B.M.); M. Piedmonte (Marion); L. Andrews (Lesley); J. Hays (John); G.C. Rodriguez (Gustavo); T. Caldes (Trinidad); M. de La Hoya (Miguel); S. Khan (Sofia); F.B.L. Hogervorst (Frans); C.M. Aalfs (Cora); J.L. de Lange (J.); E.J. Meijers-Heijboer (Hanne); A.H. van der Hout (Annemarie); J.T. Wijnen (Juul); K.E. van Roozendaal (Kees); A.R. Mensenkamp (Arjen); A.M.W. van den Ouweland (Ans); C.H.M. van Deurzen (Carolien); R.B. van der Luijt (Rob); E. Olah; O. Díez (Orland); C. Lazaro (Conxi); I. Blanco (Ignacio); A. Teulé (A.); M. Menéndez (Mireia); A. Jakubowska (Anna); J. Lubinski (Jan); C. Cybulski (Cezary); J. Gronwald (Jacek); K. Jaworska-Bieniek (Katarzyna); K. Durda (Katarzyna); A. Arason (Adalgeir); C. Maugard; P. Soucy (Penny); M. Montagna (Marco); S. Agata (Simona); P.J. Teixeira; C. Olswold (Curtis); N.M. Lindor (Noralane); V.S. Pankratz (Shane); B. Hallberg (Boubou); X. Wang (Xianshu); C. Szabo (Csilla); J. Vijai (Joseph); L. Jacobs (Lauren); M. Corines (Marina); A. Lincoln (Anne); A. Berger (Andreas); A. Fink-Retter (Anneliese); C.F. Singer (Christian); C. Rappaport (Christine); D.G. Kaulich (Daphne Gschwantler); G. Pfeiler (Georg); M.-K. Tea; C. Phelan (Catherine); P.L. Mai (Phuong); M.H. Greene (Mark); G. Rennert (Gad); E.N. Imyanitov (Evgeny); G. Glendon (Gord); A.E. Toland (Amanda); A. Bojesen (Anders); I.S. Pedersen (Inge Sokilde); U.B. Jensen; M.A. Caligo (Maria); E. Friedman (Eitan); R. Berger (Raanan); Y. Laitman (Yael); J. Rantala (Johanna); B. Arver (Brita Wasteson); N. Loman (Niklas); Å. Borg (Åke); H. Ehrencrona (Hans); O.I. Olopade (Olofunmilayo); J. Simard (Jacques); D.F. Easton (Douglas); G. Chenevix-Trench (Georgia); K. Offit (Kenneth); F.J. Couch (Fergus); A.C. Antoniou (Antonis C.); CIMBA; EMBRACE Study; Breast Cancer Family; GEMO Study Collaborators; HEBON; KConFab Investigators

    2014-01-01

    textabstractIntroduction: More than 70 common alleles are known to be involved in breast cancer (BC) susceptibility, and several exhibit significant heterogeneity in their associations with different BC subtypes. Although there are differences in the association patterns between BRCA1 and BRCA2

  13. Time-Resolved Tracking of Mutations Reveals Diverse Allele Dynamics during Escherichia coli Antimicrobial Adaptive Evolution to Single Drugs and Drug Pairs

    DEFF Research Database (Denmark)

    Hickman, Rachel A.; Munck, Christian; Sommer, Morten Otto Alexander

    2017-01-01

    + CHL and CHL + CIP). We find that lineages evolved to antibiotic combinations exhibit different resistance allele dynamics compared with those of single-drug evolved lineages, especially for a drug pair with reciprocal collateral sensitivity. During adaptation, we observed interfering, superimposing...

  14. Detection of the V1016G mutation in the voltage-gated sodium channel gene of Aedes aegypti (Diptera: Culicidae) by allele-specific PCR assay, and its distribution and effect on deltamethrin resistance in Thailand.

    Science.gov (United States)

    Stenhouse, Steven A; Plernsub, Suriya; Yanola, Jintana; Lumjuan, Nongkran; Dantrakool, Anchalee; Choochote, Wej; Somboon, Pradya

    2013-08-30

    Resistance to pyrethroid insecticides is widespread among populations of Aedes aegypti, the main vector for the dengue virus. Several different point mutations within the voltage-gated sodium channel (VGSC) gene contribute to such resistance. A mutation at position 1016 in domain II, segment 6 of the VGSC gene in Ae. aegypti leads to a valine to glycine substitution (V1016G) that confers resistance to deltamethrin. This study developed and utilized an allele-specific PCR (AS-PCR) assay that could be used to detect the V1016G mutation. The assay was validated against a number of sequenced DNA samples of known genotype and was determined to be in complete agreement. Larvae and pupae were collected from various localities throughout Thailand. Samples were reared to adulthood and their resistance status against deltamethrin was determined by standard WHO susceptibility bioassays. Deltamethrin-resistant and susceptible insects were then genotyped for the V1016G mutation. Additionally, some samples were genotyped for a second mutation at position 1534 in domain III (F1534C) which is also known to confer pyrethroid resistance. The bioassay results revealed an overall mortality of 77.6%. Homozygous 1016G individuals survived at higher rates than either heterozygous or wild-type (1016 V) mosquitoes. The 1016G mutation was significantly and positively associated with deltamethrin resistance and was widely distributed throughout Thailand. Interestingly, wild-type 1016 V mosquitoes tested were homozygous for the 1534C mutation, and all heterozygous mosquitoes were also heterozygous for 1534C. Mutant homozygous (G/G) mosquitoes expressed the wild-type (F/F) at position 1534. However, the presence of the 1534C mutation was not associated with deltamethrin resistance. Our bioassay results indicate that all populations sampled display some degree of resistance to deltamethrin. Homozygous 1016G mosquitoes were far likelier to survive such exposure. However, resistance in some

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

    Science.gov (United States)

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

    2017-10-01

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

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

    Directory of Open Access Journals (Sweden)

    Julia Jecel MD

    2015-11-01

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

  17. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers.

    OpenAIRE

    Cox, D. G.; Simard, J.; Sinnett, D.; Hamdi, Y.; Soucy, P.; Ouimet, M.; Barjhoux, L.; Verny-Pierre, C.; McGuffog, L.; Healey, S.; Szabo, C.; Greene, M. H.; Mai, P. L.; Andrulis, I. L.; Thomassen, M.

    2011-01-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly instrumental in safeguarding cells against tumorigenesis. We hypothesized that polymorphisms that alter the expression and/or function of BRCA1 carried on the wild-type (non-mutated) copy of the BRCA...

  18. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers

    NARCIS (Netherlands)

    Cox, David G.; Simard, Jacques; Sinnett, Daniel; Hamdi, Yosr; Soucy, Penny; Ouimet, Manon; Barjhoux, Laure; Verny-Pierre, Carole; McGuffog, Lesley; Healey, Sue; Szabo, Csilla; Greene, Mark H.; Mai, Phuong L.; Andrulis, Irene L.; Thomassen, Mads; Gerdes, Anne-Marie; Caligo, Maria A.; Friedman, Eitan; Laitman, Yael; Kaufman, Bella; Paluch, Shani S.; Borg, Åke; Karlsson, Per; Askmalm, Marie Stenmark; Bustinza, Gisela Barbany; Nathanson, Katherine L.; Domchek, Susan M.; Rebbeck, Timothy R.; Benítez, Javier; Hamann, Ute; Rookus, Matti A.; van den Ouweland, Ans M. W.; Ausems, Margreet G. E. M.; Aalfs, Cora M.; van Asperen, Christi J.; Devilee, Peter; Gille, Hans J. J. P.; Peock, Susan; Frost, Debra; Evans, D. Gareth; Eeles, Ros; Izatt, Louise; Adlard, Julian; Paterson, Joan; Eason, Jacqueline; Godwin, Andrew K.; Remon, Marie-Alice; Moncoutier, Virginie; van Os, T. A.; Meijers-Heijboer, H. E. J.

    2011-01-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly

  19. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers

    DEFF Research Database (Denmark)

    Cox, David G; Simard, Jacques; Sinnett, Daniel

    2011-01-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly...

  20. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers.

    NARCIS (Netherlands)

    Cox, D.G.; Simard, J.; Sinnett, D.; Hamdi, Y.; Soucy, P.; Ouimet, M.; Barjhoux, L.; Verny-Pierre, C.; McGuffog, L.; Healey, S.; Szabo, C.; Greene, M.H.; Mai, P.L.; Andrulis, I.L.; Thomassen, M.; Gerdes, A.M.; Caligo, M.A.; Friedman, E.; Laitman, Y.; Kaufman, B.; Paluch, S.S.; Borg, A.; Karlsson, P.; Askmalm, M.S.; Bustinza, G.B.; Nathanson, K.L.; Domchek, S.M.; Rebbeck, T.R.; Benitez, J.; Hamann, U.; Rookus, M.A.; Ouweland, A.M. van den; Ausems, M.G.; Aalfs, C.M.; Asperen, C.J. van; Devilee, P.; Gille, H.J.; Peock, S.; Frost, D.; Evans, D.G.; Eeles, R.; Izatt, L.; Adlard, J.; Paterson, J.; Eason, J.; Godwin, A.K.; Remon, M.A.; Moncoutier, V.; Gauthier-Villars, M.; Lasset, C.; Giraud, S.; Hardouin, A.; Berthet, P.; Sobol, H.; Eisinger, F.; Bressac de Paillerets, B.; Caron, O.; Delnatte, C.; Goldgar, D.; Miron, A.; Ozcelik, H.; Buys, S.; Southey, M.C.; Terry, M.B.; Singer, C.F.; Dressler, A.C.; Tea, M.K.; Hansen, T.V.; Johannsson, O.; Piedmonte, M.; Rodriguez, G.C.; Basil, J.B.; Blank, S.; Toland, A.E.; Montagna, M.; Isaacs, C.; Blanco, I.; Gayther, S.A.; Moysich, K.B.; Schmutzler, R.K.; Wappenschmidt, B.; Engel, C.; Meindl, A.; Ditsch, N.; Arnold, N.; Niederacher, D.; Sutter, C.; Gadzicki, D.; Fiebig, B.; Caldes, T.; Laframboise, R.; Nevanlinna, H.; Chen, X.; Beesley, J.; Spurdle, A.B.; Neuhausen, S.L.; Ding, Y.C.; Couch, F.J.; Wang, X.; Peterlongo, P.; Manoukian, S.; Bernard, L.; Radice, P.; Easton, D.F.; Chenevix-Trench, G.; Antoniou, A.C.; Stoppa-Lyonnet, D.; Mazoyer, S.; Sinilnikova, O.M.; Ligtenberg, M.J.L.; Hoogerbrugge, N.; et al.,

    2011-01-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly

  1. Common breast cancer susceptibility alleles and the risk of breast cancer for BRCA1 and BRCA2 mutation carriers: implications for risk prediction

    DEFF Research Database (Denmark)

    Antoniou, Antonis C; Beesley, Jonathan; McGuffog, Lesley

    2010-01-01

    The known breast cancer susceptibility polymorphisms in FGFR2, TNRC9/TOX3, MAP3K1, LSP1, and 2q35 confer increased risks of breast cancer for BRCA1 or BRCA2 mutation carriers. We evaluated the associations of 3 additional single nucleotide polymorphisms (SNPs), rs4973768 in SLC4A7/NEK10, rs650495...

  2. Spectrum of FANCA mutations in Italian Fanconi anemia patients: identification of six novel alleles and phenotypic characterization of the S858R variant.

    Science.gov (United States)

    Savino, Maria; Borriello, Adriana; D'Apolito, Maria; Criscuolo, Maria; Del Vecchio, Maria; Bianco, Anna Monica; Di Perna, Michele; Calzone, Rita; Nobili, Bruno; Zatterale, Adriana; Zelante, Leopoldo; Joenje, Hans; Della Ragione, Fulvio; Savoia, Anna

    2003-10-01

    Fanconi anemia (FA) is an autosomal recessive disorder characterized by genomic instability, bone marrow failure, congenital malformations, and cancer predisposition. FA is a genetically heterogeneous disease with at least seven genes so far identified. The role of FA proteins is unknown although they interact in a common functional pathway. Here, we report six novel FANCA sequence changes and review all the mutations identified in Italy. Except for two missense substitutions, all are expected to cause a premature termination of the FANCA protein at various sites throughout the molecule. The premature terminations are due to nonsense and splice site mutations, as well as small insertions and deletions, and large genomic rearrangements. The expected truncated proteins were not detectable on Western blot analyses. The FANCA-S858R variant is instead expressed at lower level than that seen in normal cell lines and is associated with a non-ubiquinated FANCD2 protein, strongly suggesting that the amino acid substitution is a disease-causing mutation. The spectrum of FA mutations is widely in agreement with the heterogeneous ethnic origin of the Italian population. Copyright 2003 Wiley-Liss, Inc.

  3. Allele frequencies of hemojuvelin gene (HJV I222N and G320V missense mutations in white and African American subjects from the general Alabama population

    Directory of Open Access Journals (Sweden)

    Bohannon Sean B

    2004-12-01

    Full Text Available Abstract Background Homozygosity or compound heterozygosity for coding region mutations of the hemojuvelin gene (HJV in whites is a cause of early age-of-onset iron overload (juvenile hemochromatosis, and of hemochromatosis phenotypes in some young or middle-aged adults. HJV coding region mutations have also been identified recently in African American primary iron overload and control subjects. Primary iron overload unexplained by typical hemochromatosis-associated HFE genotypes is common in white and black adults in Alabama, and HJV I222N and G320V were detected in a white Alabama juvenile hemochromatosis index patient. Thus, we estimated the frequency of the HJV missense mutations I222N and G320V in adult whites and African Americans from Alabama general population convenience samples. Methods We evaluated the genomic DNA of 241 Alabama white and 124 African American adults who reported no history of hemochromatosis or iron overload to detect HJV missense mutations I222N and G320V using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP technique. Analysis for HJV I222N was performed in 240 whites and 124 African Americans. Analysis for HJV G320V was performed in 241 whites and 118 African Americans. Results One of 240 white control subjects was heterozygous for HJV I222N; she was also heterozygous for HFE C282Y, but had normal serum iron measures and bone marrow iron stores. HJV I222N was not detected in 124 African American subjects. HJV G320V was not detected in 241 white or 118 African American subjects. Conclusions HJV I222N and G320V are probably uncommon causes or modifiers of primary iron overload in adult whites and African Americans in Alabama. Double heterozygosity for HJV I222N and HFE C282Y may not promote increased iron absorption.

  4. Cloning of an E. coli RecA and yeast RAD51 homolog, radA, an allele of the uvsC in Aspergillus nidulans and its mutator effects.

    Science.gov (United States)

    Seong, K Y; Chae, S K; Kang, H S

    1997-04-30

    An E. coli RecA and yeast RAD51 homolog from Aspergillus nidulans, radA, has been cloned by screening genomic and cDNA libraries with a PCR-amplified probe. This probe was generated using primers carrying the conserved sequences of eukaryotic RecA homologs. The deduced amino acid sequence revealed two conserved Walker-A and -B type nucleotide-binding domains and exhibited 88%, 60%, and 53% identity with Mei-3 of Neurospora crassa, rhp51+ of Schizosaccharomyces pombe, and Rad51 of Saccharomyces cerevisiae, respectively. radA null mutants constructed by replacing the whole coding region with a selection marker showed high methyl methanesulfonate (MMS) sensitivity. Heterozygous diploids of radA disruptant with the uvsC114 mutant failed to complement with respect to MMS-sensitivity, indicating that radA is an allele of uvsC. In selecting spontaneous forward selenate resistant mutations, mutator effects were observed in radA null mutants similarly to those shown in uvsC114 mutant strains.

  5. A novel Gerstmann-Sträussler-Scheinker disease mutation defines a precursor for amyloidogenic 8 kDa PrP fragments and reveals N-terminal structural changes shared by other GSS alleles

    Science.gov (United States)

    Mercer, Robert C. C.; Fu, Ze-Lin; Mays, Charles E.; Gapeshina, Hristina; Wohlgemuth, Serene L.; Acevedo-Morantes, Claudia Y.; Cashman, Neil R.; Coulthart, Michael B.; Jansen, Gerard H.; Stepanova, Maria

    2018-01-01

    To explore pathogenesis in a young Gerstmann-Sträussler-Scheinker Disease (GSS) patient, the corresponding mutation, an eight-residue duplication in the hydrophobic region (HR), was inserted into the wild type mouse PrP gene. Transgenic (Tg) mouse lines expressing this mutation (Tg.HRdup) developed spontaneous neurologic syndromes and brain extracts hastened disease in low-expressor Tg.HRdup mice, suggesting de novo formation of prions. While Tg.HRdup mice exhibited spongiform change, PrP aggregates and the anticipated GSS hallmark of a proteinase K (PK)-resistant 8 kDa fragment deriving from the center of PrP, the LGGLGGYV insertion also imparted alterations in PrP's unstructured N-terminus, resulting in a 16 kDa species following thermolysin exposure. This species comprises a plausible precursor to the 8 kDa PK-resistant fragment and its detection in adolescent Tg.HRdup mice suggests that an early start to accumulation could account for early disease of the index case. A 16 kDa thermolysin-resistant signature was also found in GSS patients with P102L, A117V, H187R and F198S alleles and has coordinates similar to GSS stop codon mutations. Our data suggest a novel shared pathway of GSS pathogenesis that is fundamentally distinct from that producing structural alterations in the C-terminus of PrP, as observed in other prion diseases such as Creutzfeldt-Jakob Disease and scrapie. PMID:29338055

  6. A study of Huntington disease-like syndromes in black South African patients reveals a single SCA2 mutation and a unique distribution of normal alleles across five repeat loci.

    Science.gov (United States)

    Baine, Fiona K; Peerbhai, Nabeelah; Krause, Amanda

    2018-07-15

    Huntington disease (HD) is a progressive neurodegenerative disease, characterised by a triad of movement disorder, emotional and behavioural disturbances and cognitive impairment. The underlying cause is an expanded CAG repeat in the huntingtin gene. For a small proportion of patients presenting with HD-like symptoms, the mutation in this gene is not identified and they are said to have a HD "phenocopy". South Africa has the highest number of recorded cases of an African-specific phenocopy, Huntington disease-like 2 (HDL2), caused by a repeat expansion in the junctophilin-3 gene. However, a significant proportion of black patients with clinical symptoms suggestive of HD still test negative for HD and HDL2. This study thus aimed to investigate five other loci associated with HD phenocopy syndromes - ATN1, ATXN2, ATXN7, TBP and C9orf72. In a sample of patients in whom HD and HDL2 had been excluded, a single expansion was identified in the ATXN2 gene, confirming a diagnosis of Spinocerebellar ataxia 2. The results indicate that common repeat expansion disorders do not contribute significantly to the HD-like phenotype in black South African patients. Importantly, allele sizing reveals unique distributions of normal repeat lengths across the associated loci in the African population studied. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Common breast cancer susceptibility alleles are associated with tumor subtypes in BRCA1 and BRCA2 mutation carriers: results from the Consortium of Investigators of Modifiers of BRCA1/2

    DEFF Research Database (Denmark)

    Mulligan, Anna Marie; Couch, Fergus J; Barrowdale, Daniel

    2011-01-01

    BRCA1 carriers, SNP rs2981582 (FGFR2) exhibited the biggest difference based on ER status (per-allele HR for ER-positive=1.35, 95%CI:1.17-1.56 vs HR=0.91, 95%CI:0.85-0.98 for ER-negative, P-heterogeneity=6.5e-6). In contrast, SNP rs2046210 at 6q25.1 near ESR1 was primarily associated with ER...... in BRCA1 and BRCA2 mutation carriers defined by estrogen (ER) or progesterone receptor (PR) status of the tumor. METHODS: We used genotype data on up to 11,421 BRCA1 and 7,080 BRCA2 carriers, of whom 4,310 had been affected with breast cancer and had information on either ER or PR status of the tumor......, to assess the associations of twelve loci with breast cancer tumor characteristics. Associations were evaluated using a retrospective cohort approach. RESULTS: The results suggested stronger associations with ER-positive breast cancer than ER-negative for eleven loci in both BRCA1 and BRCA2 carriers. Among...

  8. M19 modulates skeletal muscle differentiation and insulin secretion in pancreatic β-cells through modulation of respiratory chain activity.

    Directory of Open Access Journals (Sweden)

    Linda Cambier

    Full Text Available Mitochondrial dysfunction due to nuclear or mitochondrial DNA alterations contributes to multiple diseases such as metabolic myopathies, neurodegenerative disorders, diabetes and cancer. Nevertheless, to date, only half of the estimated 1,500 mitochondrial proteins has been identified, and the function of most of these proteins remains to be determined. Here, we characterize the function of M19, a novel mitochondrial nucleoid protein, in muscle and pancreatic β-cells. We have identified a 13-long amino acid sequence located at the N-terminus of M19 that targets the protein to mitochondria. Furthermore, using RNA interference and over-expression strategies, we demonstrate that M19 modulates mitochondrial oxygen consumption and ATP production, and could therefore regulate the respiratory chain activity. In an effort to determine whether M19 could play a role in the regulation of various cell activities, we show that this nucleoid protein, probably through its modulation of mitochondrial ATP production, acts on late muscle differentiation in myogenic C2C12 cells, and plays a permissive role on insulin secretion under basal glucose conditions in INS-1 pancreatic β-cells. Our results are therefore establishing a functional link between a mitochondrial nucleoid protein and the modulation of respiratory chain activities leading to the regulation of major cellular processes such as myogenesis and insulin secretion.

  9. MPL mutations in myeloproliferative disorders

    DEFF Research Database (Denmark)

    Beer, Philip A.; Campbell, Peter J.; Scott, Linda M.

    2008-01-01

    Activating mutations of MPL exon 10 have been described in a minority of patients with idiopathic myelofibrosis (IMF) or essential thrombocythemia (ET), but their prevalence and clinical significance are unclear. Here we demonstrate that MPL mutations outside exon 10 are uncommon in platelet c......DNA and identify 4 different exon 10 mutations in granulocyte DNA from a retrospective cohort of 200 patients with ET or IMF. Allele-specific polymerase chain reaction was then used to genotype 776 samples from patients with ET entered into the PT-1 studies. MPL mutations were identified in 8.5% of JAK2 V617F......(-) patients and a single V617F(+) patient. Patients carrying the W515K allele had a significantly higher allele burden than did those with the W515L allele, suggesting a functional difference between the 2 variants. Compared with V617F(+) ET patients, those with MPL mutations displayed lower hemoglobin...

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

    Directory of Open Access Journals (Sweden)

    Kai Hung Tiong

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

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

    NARCIS (Netherlands)

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

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

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

    NARCIS (Netherlands)

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

    2016-01-01

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

  13. Potyviral resistance derived from cultivars of Phaseolus vulgaris carrying bc-3 co-segregates with homozygotic presence of a mutated eIF4E allele

    DEFF Research Database (Denmark)

    Naderpour, M; Lund, O Søgaard; Larsen, R

    2008-01-01

    -binding proteins, eIF4E, eIF(iso)4E and nCBP. In cultivars reported to carry bc-3 resistance, eIF4E was found to display non-silent mutations at codons 53, 65, 76 and 111 closely resembling a pattern of eIF4E mutations determining potyvirus resistance in other plant species. By application of a molecular marker...

  14. SSR allelic variation in almond (Prunus dulcis Mill.).

    Science.gov (United States)

    Xie, Hua; Sui, Yi; Chang, Feng-Qi; Xu, Yong; Ma, Rong-Cai

    2006-01-01

    Sixteen SSR markers including eight EST-SSR and eight genomic SSRs were used for genetic diversity analysis of 23 Chinese and 15 international almond cultivars. EST- and genomic SSR markers previously reported in species of Prunus, mainly peach, proved to be useful for almond genetic analysis. DNA sequences of 117 alleles of six of the 16 SSR loci were analysed to reveal sequence variation among the 38 almond accessions. For the four SSR loci with AG/CT repeats, no insertions or deletions were observed in the flanking regions of the 98 alleles sequenced. Allelic size variation of these loci resulted exclusively from differences in the structures of repeat motifs, which involved interruptions or occurrences of new motif repeats in addition to varying number of AG/CT repeats. Some alleles had a high number of uninterrupted repeat motifs, indicating that SSR mutational patterns differ among alleles at a given SSR locus within the almond species. Allelic homoplasy was observed in the SSR loci because of base substitutions, interruptions or compound repeat motifs. Substitutions in the repeat regions were found at two SSR loci, suggesting that point mutations operate on SSRs and hinder the further SSR expansion by introducing repeat interruptions to stabilize SSR loci. Furthermore, it was shown that some potential point mutations in the flanking regions are linked with new SSR repeat motif variation in almond and peach.

  15. Distribution of a pseudodeficiency allele among Tay-Sachs carriers

    Energy Technology Data Exchange (ETDEWEB)

    Tomczak, J.; Grebner, E.E. (Thomas Jefferson Univ., Philadelphia, PA (United States)); Boogen, C. (Univ. of Essen Medical School (Germany))

    1993-08-01

    Recently Triggs-Raine et al. (1992) identified a new mutation in the gene coding for the [alpha]-subunit of [beta]-hexosaminidase A (hex A), the enzyme whose deficiency causes Tay-Sachs disease. This mutation, a C[sub 739]-to-T transition in exon 7, results in an altered enzyme that is active (albeit at reduced levels) in cells but that has essentially no activity in serum. This so-called pseudodeficient allele was first detected in compound heterozygotes who also carried a Tay-Sachs disease allele and therefore had no detectable hex A in their serum but who were in good health. Carriers of this apparently benign mutation are generally indistinguishable from carriers of a lethal mutation by means of routine enzyme-based screening tests, because the product of the pseudodeficient allele is not detectable in serum and has decreased activity in cells. This suggests that some individuals who have been classified as Tay-Sachs carriers are actually carriers of the pseudodeficient allele and are not at risk to have a child affected with Tay-Sachs disease. The pseudodeficient allele may also be responsible for some inconclusive diagnoses, where leukocyte values fall below the normal range but are still above the carrier range. The fact that there are now two mutant alleles (the psuedodeficient and the adult) that are indistinguishable from the lethal infantile mutations by means of enzyme assay yet that are phenotypically very different and that together may account for as much as 12% of enzyme-defined carriers on the basis of the data here suggests that DNA analysis should be part of a comprehensive screening program. It will be particularly useful to identify the mutations in couples at risk, before they undergo prenatal diagnosis. DNA analysis will also resolve some inconclusive diagnoses.

  16. Intrinsic MYH7 expression regulation contributes to tissue level allelic imbalance in hypertrophic cardiomyopathy.

    Science.gov (United States)

    Montag, Judith; Syring, Mandy; Rose, Julia; Weber, Anna-Lena; Ernstberger, Pia; Mayer, Anne-Kathrin; Becker, Edgar; Keyser, Britta; Dos Remedios, Cristobal; Perrot, Andreas; van der Velden, Jolanda; Francino, Antonio; Navarro-Lopez, Francesco; Ho, Carolyn Yung; Brenner, Bernhard; Kraft, Theresia

    2017-08-01

    HCM, the most common inherited cardiac disease, is mainly caused by mutations in sarcomeric genes. More than a third of the patients are heterozygous for mutations in the MYH7 gene encoding for the β-myosin heavy chain. In HCM-patients, expression of the mutant and the wildtype allele can be unequal, thus leading to fractions of mutant and wildtype mRNA and protein which deviate from 1:1. This so-called allelic imbalance was detected in whole tissue samples but also in individual cells. There is evidence that the severity of HCM not only depends on the functional effect of the mutation itself, but also on the fraction of mutant protein in the myocardial tissue. Allelic imbalance has been shown to occur in a broad range of genes. Therefore, we aimed to examine whether the MYH7-alleles are intrinsically expressed imbalanced or whether the allelic imbalance is solely associated with the disease. We compared the expression of MYH7-alleles in non-HCM donors and in HCM-patients with different MYH7-missense mutations. In the HCM-patients, we identified imbalanced as well as equal expression of both alleles. Also at the protein level, allelic imbalance was determined. Most interestingly, we also discovered allelic imbalance and balance in non-HCM donors. Our findings therefore strongly indicate that apart from mutation-specific mechanisms, also non-HCM associated allelic-mRNA expression regulation may account for the allelic imbalance of the MYH7 gene in HCM-patients. Since the relative amount of mutant mRNA and protein or the extent of allelic imbalance has been associated with the severity of HCM, individual analysis of the MYH7-allelic expression may provide valuable information for the prognosis of each patient.

  17. Two missense mutations, E123Q and K151E, identified in the ERG11 allele of an azole-resistant isolate of Candida kefyr recovered from a stem cell transplant patient for acute myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Célia Couzigou

    2014-07-01

    Full Text Available We report on the first cloning and nucleotide sequencing of an ERG11 allele from a clinical isolate of Candida kefyr cross-resistant to azole antifungals. It was recovered from a stem cell transplant patient, in an oncohematology unit exhibiting unexpected high prevalence of C. kefyr. Two amino acid substitutions were identified: K151E, whose role in fluconazole resistance was already demonstrated in Candida albicans, and E123Q, a new substitution never described so far in azole-resistant Candida yeast.

  18. Analysis of productive evolution of well M-19A, Cerro Prieto geothermal field, BC; Analisis de la evolucion productiva del pozo M-19A del campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Rodriguez, Marco H; Romero-Rios, Francisco [Comision Federal de Electricidad, Residencia General de Cerro Prieto, B.C (Mexico)]. E-mail: marco.rodriguez01@cfe.gob.mx

    2007-07-15

    Well M-19A has been the most productive in the Cerro Prieto field, producing around 40 million tons of fluid. The well went on line in February 1975 and was in continuous operation until June 2006. Monthly measurements for over 30 years of operating conditions and chemical and isotopic analyses of the fluids allow identification of the most significant processes occurring in the zone where the well is located. Three dominant recharge types have been identified, each lasting about 10 years. They are a) a recharge of fluids of lower temperature than the production fluids, even though the chemical and isotopic compositions are similar; b) a recharge of lower-temperature fluids with diluted chemical and isotopic compositions; and c) a progressive recharge of reinjected water with a higher chloride concentration and heavy isotopic composition. The production and reinjection rates for over 30 years of production history in the M-19A well zone allow for speculation of a reservoir pressure recovery, which is confirmed with a calculation using production data from well M-19A. The evolution of the reservoir pressure in the zone contrasts with the rest of the reservoir, where a constant pressure drop is observed, particularly toward the central and eastern parts of the field. [Spanish] El pozo M-19A ha sido el mas productivo del campo geotermico de Cerro Prieto, BC, alcanzando una extraccion de mas de 40 millones de toneladas de fluido. Fue integrado a produccion en febrero de 1975 y hasta junio de 2006 ha permanecido en produccion en forma continua. Las mediciones mensuales de sus condiciones operativas y los analisis quimicos e isotopicos del agua producida permiten identificar los procesos mas significativos que han ocurrido a lo largo de esos mas de 30 anos en la zona donde se localiza el pozo. Se han identificado tres tipos de recarga dominantes que se presentan durante un periodo cercano a 10 anos cada uno, los cuales son: a) una recarga de fluidos de menor temperatura

  19. Allele-specific characterization of alanine: glyoxylate aminotransferase variants associated with primary hyperoxaluria.

    Directory of Open Access Journals (Sweden)

    Melissa D Lage

    Full Text Available Primary Hyperoxaluria Type 1 (PH1 is a rare autosomal recessive kidney stone disease caused by deficiency of the peroxisomal enzyme alanine: glyoxylate aminotransferase (AGT, which is involved in glyoxylate detoxification. Over 75 different missense mutations in AGT have been found associated with PH1. While some of the mutations have been found to affect enzyme activity, stability, and/or localization, approximately half of these mutations are completely uncharacterized. In this study, we sought to systematically characterize AGT missense mutations associated with PH1. To facilitate analysis, we used two high-throughput yeast-based assays: one that assesses AGT specific activity, and one that assesses protein stability. Approximately 30% of PH1-associated missense mutations are found in conjunction with a minor allele polymorphic variant, which can interact to elicit complex effects on protein stability and trafficking. To better understand this allele interaction, we functionally characterized each of 34 mutants on both the major (wild-type and minor allele backgrounds, identifying mutations that synergize with the minor allele. We classify these mutants into four distinct categories depending on activity/stability results in the different alleles. Twelve mutants were found to display reduced activity in combination with the minor allele, compared with the major allele background. When mapped on the AGT dimer structure, these mutants reveal localized regions of the protein that appear particularly sensitive to interactions with the minor allele variant. While the majority of the deleterious effects on activity in the minor allele can be attributed to synergistic interaction affecting protein stability, we identify one mutation, E274D, that appears to specifically affect activity when in combination with the minor allele.

  20. The Structure of the Lipid A from the Halophilic Bacterium Spiribacter salinus M19-40T

    Directory of Open Access Journals (Sweden)

    Clara Barrau

    2018-04-01

    Full Text Available The study of the adaptation mechanisms that allow microorganisms to live and proliferate in an extreme habitat is a growing research field. Directly exposed to the external environment, lipopolysaccharides (LPS from Gram-negative bacteria are of great appeal as they can present particular structural features that may aid the understanding of the adaptation processes. Moreover, through being involved in modulating the mammalian immune system response in a structure-dependent fashion, the elucidation of the LPS structure can also be seen as a fundamental step from a biomedical point of view. In this paper, the lipid A structure of the LPS from Spiribacter salinus M19-40T, a halophilic gamma-proteobacteria, was characterized through chemical analyses and matrix-assisted laser desorption ionization (MALDI mass spectrometry. This revealed a mixture of mono- and bisphosphorylated penta- to tri-acylated species with the uncommon 2 + 3 symmetry and bearing an unusual 3-oxotetradecaonic acid.

  1. A strategy to discover genes that carry multi-allelic or mono-allelic risk for common diseases: A cohort allelic sums test (CAST)

    International Nuclear Information System (INIS)

    Morgenthaler, Stephan; Thilly, William G.

    2007-01-01

    A method is described to discover if a gene carries one or more allelic mutations that confer risk for any specified common disease. The method does not depend upon genetic linkage of risk-conferring mutations to high frequency genetic markers such as single nucleotide polymorphisms. Instead, the sums of allelic mutation frequencies in case and control cohorts are determined and a statistical test is applied to discover if the difference in these sums is greater than would be expected by chance. A statistical model is presented that defines the ability of such tests to detect significant gene-disease relationships as a function of case and control cohort sizes and key confounding variables: zygosity and genicity, environmental risk factors, errors in diagnosis, limits to mutant detection, linkage of neutral and risk-conferring mutations, ethnic diversity in the general population and the expectation that among all exonic mutants in the human genome greater than 90% will be neutral with regard to any effect on disease risk. Means to test the null hypothesis for, and determine the statistical power of, each test are provided. For this 'cohort allelic sums test' or 'CAST', the statistical model and test are provided as an Excel (TM) program, CASTAT (C) at http://epidemiology.mit.edu. Based on genetics, technology and statistics, a strategy of enumerating the mutant alleles carried in the exons and splice sites of the estimated ∼25,000 human genes in case cohort samples of 10,000 persons for each of 100 common diseases is proposed and evaluated: A wide range of possible conditions of multi-allelic or mono-allelic and monogenic, multigenic or polygenic (including epistatic) risk are found to be detectable using the statistical criteria of 1 or 10 ''false positive'' gene associations per 25,000 gene-disease pair-wise trials and a statistical power of >0.8. Using estimates of the distribution of both neutral and gene-inactivating nondeleterious mutations in humans and

  2. Allele coding in genomic evaluation

    Directory of Open Access Journals (Sweden)

    Christensen Ole F

    2011-06-01

    Full Text Available Abstract Background Genomic data are used in animal breeding to assist genetic evaluation. Several models to estimate genomic breeding values have been studied. In general, two approaches have been used. One approach estimates the marker effects first and then, genomic breeding values are obtained by summing marker effects. In the second approach, genomic breeding values are estimated directly using an equivalent model with a genomic relationship matrix. Allele coding is the method chosen to assign values to the regression coefficients in the statistical model. A common allele coding is zero for the homozygous genotype of the first allele, one for the heterozygote, and two for the homozygous genotype for the other allele. Another common allele coding changes these regression coefficients by subtracting a value from each marker such that the mean of regression coefficients is zero within each marker. We call this centered allele coding. This study considered effects of different allele coding methods on inference. Both marker-based and equivalent models were considered, and restricted maximum likelihood and Bayesian methods were used in inference. Results Theoretical derivations showed that parameter estimates and estimated marker effects in marker-based models are the same irrespective of the allele coding, provided that the model has a fixed general mean. For the equivalent models, the same results hold, even though different allele coding methods lead to different genomic relationship matrices. Calculated genomic breeding values are independent of allele coding when the estimate of the general mean is included into the values. Reliabilities of estimated genomic breeding values calculated using elements of the inverse of the coefficient matrix depend on the allele coding because different allele coding methods imply different models. Finally, allele coding affects the mixing of Markov chain Monte Carlo algorithms, with the centered coding being

  3. Allele coding in genomic evaluation

    DEFF Research Database (Denmark)

    Standen, Ismo; Christensen, Ole Fredslund

    2011-01-01

    Genomic data are used in animal breeding to assist genetic evaluation. Several models to estimate genomic breeding values have been studied. In general, two approaches have been used. One approach estimates the marker effects first and then, genomic breeding values are obtained by summing marker...... effects. In the second approach, genomic breeding values are estimated directly using an equivalent model with a genomic relationship matrix. Allele coding is the method chosen to assign values to the regression coefficients in the statistical model. A common allele coding is zero for the homozygous...... genotype of the first allele, one for the heterozygote, and two for the homozygous genotype for the other allele. Another common allele coding changes these regression coefficients by subtracting a value from each marker such that the mean of regression coefficients is zero within each marker. We call...

  4. Mutation and premating isolation

    Science.gov (United States)

    Woodruff, R. C.; Thompson, J. N. Jr

    2002-01-01

    While premating isolation might be traceable to different genetic mechanisms in different species, evidence supports the idea that as few as one or two genes may often be sufficient to initiate isolation. Thus, new mutation can theoretically play a key role in the process. But it has long been thought that a new isolation mutation would fail, because there would be no other individuals for the isolation-mutation-carrier to mate with. We now realize that premeiotic mutations are very common and will yield a cluster of progeny carrying the same new mutant allele. In this paper, we discuss the evidence for genetically simple premating isolation barriers and the role that clusters of an isolation mutation may play in initiating allopatric, and even sympatric, species divisions.

  5. Risk factors for development of dementia in a unique six-year cohort study. I. An exploratory, pilot study of involvement of the E4 allele of apolipoprotein E, mutations of the hemochromatosis-HFE gene, type 2 diabetes, and stroke.

    Science.gov (United States)

    Percy, Maire; Somerville, Martin J; Hicks, Mark; Garcia, Angeles; Colelli, Teresa; Wright, Emily; Kitaygorodsky, Julia; Jiang, Amy; Ho, Valerie; Parpia, Alyssa; Wong, Michael K

    2014-01-01

    Risk factors for dementia development are not well-defined. We evaluated several factors alone and in combination in a unique cohort of Caucasian volunteers over an approximately 6-year observation window using a nested case/control design. Factors included: apolipoprotein E (ApoE) gene variants (the E4 allele is the strongest confirmed genetic predisposing factor for Alzheimer's disease), the hemochromatosis-HFE gene mutations (H63D and C282Y), diabetes, and stroke. At study entry, subjects were ≥65 years of age (M ± SD = 73.0 ± 4.9), had an MMSE score ≥24, and no evidence of cerebrovascular disease or current depression. Genotyping was completed on 163 available DNA samples from three different groups at the study end: those who still had normal cognitive function; those who had developed dementia; and those with Mild Cognitive Impairment (MCI). Analyses were interpreted at the 95% confidence level without Bonferroni corrections. In the subgroup with dementia, all cases of diabetes were type 2 and present at study entry, whereas all strokes occurred during the study. The results highlight apparently synergistic interactions between genetic and medical risk factors for dementia development, gender differences in risk factors, and involvement of HFE mutations. Having E4 (i.e., either of E3/4 or E4/4), C282Y, H63D, diabetes, or stroke alone did not attain significance. Significant predisposing factors with post-hoc power ≥80% were: E4 homozygosity (E4/4)males+females, odds ratio (OR) = 56.0); E4+diabetes (males+females, OR = 13.7; E4+H63D+diabetes (females, OR = 52.0); E4+stroke (males, OR = 46.5). The importance of preventing diabetes and stroke to ward off dementia and the possible role of iron dysmetabolism in dementia are discussed.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  7. Limited efficacy of hydroxyurea in lowering of the JAK2 V617F allele burden

    DEFF Research Database (Denmark)

    Larsen, Thomas Stauffer; Pallisgaard, Niels; de Stricker, Karin

    2009-01-01

    Besides being an invaluable marker of clonal disease in chronic myeloproliferative disorders (CMPDs), the JAK2 V617F mutation and the mutated allele burden have an impact on disease phenotype and may provide information on prognosis. Recently, hydroxyurea (HU) has been shown to induce a rapid...

  8. Mutational and phenotypical spectrum of phenylalanine hydroxylase deficiency in Denmark

    DEFF Research Database (Denmark)

    Bayat, A.; Yasmeen, S.; Lund, A.

    2016-01-01

    We describe the genotypes of the complete cohort, from 1967 to 2014, of phenylketonuria (PKU) patients in Denmark, in total 376 patients. A total of 752 independent alleles were investigated. Mutations were identified on 744 PKU alleles (98.9%). In total, 82 different mutations were present...

  9. Adaptive mutation: has the unicorn landed?

    Science.gov (United States)

    Foster, P L

    1998-01-01

    Reversion of an episomal Lac- allele during lactose selection has been studied as a model for adaptive mutation. Although recent results show that the mutations that arise during selection are not "adaptive" in the original sense, the mutagenic mechanism that produces these mutations may nonetheless be of evolutionary significance. In addition, a transient mutational state induced in a subpopulation of starving cells could provide a species with a mechanism for adaptive evolution. PMID:9560365

  10. Adaptive mutation: has the unicorn landed?

    Science.gov (United States)

    Foster, P L

    1998-04-01

    Reversion of an episomal Lac- allele during lactose selection has been studied as a model for adaptive mutation. Although recent results show that the mutations that arise during selection are not "adaptive" in the original sense, the mutagenic mechanism that produces these mutations may nonetheless be of evolutionary significance. In addition, a transient mutational state induced in a subpopulation of starving cells could provide a species with a mechanism for adaptive evolution.

  11. Delimiting Allelic Imbalance of TYMS by Allele-Specific Analysis.

    Science.gov (United States)

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

    2015-07-01

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

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

    KAUST Repository

    Monies, Dorota; Maddirevula, Sateesh; Kurdi, Wesam; Alanazy, Mohammed H.; Alkhalidi, Hisham; Al-Owain, Mohammed; Sulaiman, Raashda A.; Faqeih, Eissa; Goljan, Ewa; Ibrahim, Niema; Abdulwahab, Firdous; Hashem, Mais; Abouelhoda, Mohamed; Shaheen, Ranad; Arold, Stefan T.; Alkuraya, Fowzan S.

    2017-01-01

    The purpose of this study is to describe recessive alleles in strictly dominant genes. Identifying recessive mutations in genes for which only dominant disease or risk alleles have been reported can expand our understanding of the medical relevance

  13. Lineage dynamics and mutation-selection balance in non-adapting asexual populations

    Science.gov (United States)

    Pénisson, Sophie; Sniegowski, Paul D.; Colato, Alexandre; Gerrish, Philip J.

    2013-02-01

    In classical population genetics, mutation-selection balance refers to the equilibrium frequency of a deleterious allele established and maintained under two opposing forces: recurrent mutation, which tends to increase the frequency of the allele; and selection, which tends to decrease its frequency. In a haploid population, if μ denotes the per capita rate of production of the deleterious allele by mutation and s denotes the selective disadvantage of carrying the allele, then the classical mutation-selection balance frequency of the allele is approximated by μ/s. This calculation assumes that lineages carrying the mutant allele in question—the ‘focal allele’—do not accumulate deleterious mutations linked to the focal allele. In principle, indirect selection against the focal allele caused by such additional mutations can decrease the frequency of the focal allele below the classical mutation-selection balance. This effect of indirect selection will be strongest in an asexual population, in which the entire genome is in linkage. Here, we use an approach based on a multitype branching process to investigate this effect, analyzing lineage dynamics under mutation, direct selection, and indirect selection in a non-adapting asexual population. We find that the equilibrium balance between recurrent mutation to the focal allele and the forces of direct and indirect selection against the focal allele is closely approximated by γμ/(s + U) (s = 0 if the focal allele is neutral), where γ ≈ eθθ-(ω+θ)(ω + θ)(Γ(ω + θ) - Γ(ω + θ,θ)), \\theta =U/\\tilde {s}, and \\omega =s/\\tilde {s}; U denotes the genomic deleterious mutation rate and \\tilde {s} denotes the geometric mean selective disadvantage of deleterious mutations elsewhere on the genome. This mutation-selection balance for asexual populations can remain surprisingly invariant over wide ranges of the mutation rate.

  14. Political Violence in Latin America. A Cross-Case Comparison of the Urban Insurgency Campaigns of Montoneros, M-19, and FSLN in a Historical Perspective

    NARCIS (Netherlands)

    le Blanc, J.H.C.

    2012-01-01

    The investigation reconstructs and examines the processes of escalation and de-escalation of political violence in internal conflicts in Latin America. The study analyses and compares the urban insurgent campaigns of the Argentinean Montoneros, the Colombian Movement 19 April (M-19) and the

  15. Draft Genome Sequence of Streptococcus agalactiae Serotype Ia Strain M19, a Multidrug-Resistant Isolate from a Cow with Bovine Mastitis

    OpenAIRE

    Yang, Feng; Li, Hongsheng; Zhang, Shidong; Wang, Xurong

    2016-01-01

    Streptococcus agalactiae is a major contagious pathogen causing bovine mastitis worldwide. We report here the draft sequence of S.?agalactiae Ia strain M19, a multidrug-resistant isolate from a bovine mastitis case in Ningxia Hui autonomous region, China.

  16. Experimental evolution and the dynamics of genomic mutation rate modifiers.

    Science.gov (United States)

    Raynes, Y; Sniegowski, P D

    2014-11-01

    Because genes that affect mutation rates are themselves subject to mutation, mutation rates can be influenced by natural selection and other evolutionary forces. The population genetics of mutation rate modifier alleles has been a subject of theoretical interest for many decades. Here, we review experimental contributions to our understanding of mutation rate modifier dynamics. Numerous evolution experiments have shown that mutator alleles (modifiers that elevate the genomic mutation rate) can readily rise to high frequencies via genetic hitchhiking in non-recombining microbial populations. Whereas these results certainly provide an explanatory framework for observations of sporadically high mutation rates in pathogenic microbes and in cancer lineages, it is nonetheless true that most natural populations have very low mutation rates. This raises the interesting question of how mutator hitchhiking is suppressed or its phenotypic effect reversed in natural populations. Very little experimental work has addressed this question; with this in mind, we identify some promising areas for future experimental investigation.

  17. Expanding CEP290 mutational spectrum in ciliopathies

    NARCIS (Netherlands)

    Travaglini, Lorena; Brancati, Francesco; Attie-Bitach, Tania; Audollent, Sophie; Bertini, Enrico; Kaplan, Josseline; Perrault, Isabelle; Iannicelli, Miriam; Mancuso, Brunella; Rigoli, Luciana; Rozet, Jean-Michel; Swistun, Dominika; Tolentino, Jerlyn; Dallapiccola, Bruno; Gleeson, Joseph G.; Valente, Enza Maria; Zankl, A.; Leventer, R.; Grattan-Smith, P.; Janecke, A.; D'Hooghe, M.; Sznajer, Y.; van Coster, R.; Demerleir, L.; Dias, K.; Moco, C.; Moreira, A.; Kim, C. Ae; Maegawa, G.; Petkovic, D.; Abdel-Salam, G. M. H.; Abdel-Aleem, A.; Zaki, M. S.; Marti, I.; Quijano-Roy, S.; Sigaudy, S.; de Lonlay, P.; Romano, S.; Touraine, R.; Koenig, M.; Lagier-Tourenne, C.; Messer, J.; Collignon, P.; Wolf, N.; Philippi, H.; Kitsiou Tzeli, S.; Halldorsson, S.; Johannsdottir, J.; Ludvigsson, P.; Phadke, S. R.; Udani, V.; Stuart, B.; Magee, A.; Lev, D.; Michelson, M.; Ben-Zeev, B.; Fischetto, R.; Benedicenti, F.; Stanzial, F.; Borgatti, R.; Accorsi, P.; Battaglia, S.; Fazzi, E.; Giordano, L.; Pinelli, L.; Boccone, L.; Bigoni, S.; Ferlini, A.; Donati, M. A.; Caridi, G.; Divizia, M. T.; Faravelli, F.; Ghiggeri, G.; Pessagno, A.; Briguglio, M.; Briuglia, S.; Salpietro, C. D.; Tortorella, G.; Adami, A.; Castorina, P.; Lalatta, F.; Marra, G.; Riva, D.; Scelsa, B.; Spaccini, L.; Uziel, G.; del Giudice, E.; Laverda, A. M.; Ludwig, K.; Permunian, A.; Suppiej, A.; Signorini, S.; Uggetti, C.; Battini, R.; Di Giacomo, M.; Cilio, M. R.; Di Sabato, M. L.; Leuzzi, V.; Parisi, P.; Pollazzon, M.; Silengo, M.; de Vescovi, R.; Greco, D.; Romano, C.; Cazzagon, M.; Simonati, A.; Al-Tawari, A. A.; Bastaki, L.; Mégarbané, A.; Sabolic Avramovska, V.; de Jong, M. M.; Stromme, P.; Koul, R.; Rajab, A.; Azam, M.; Barbot, C.; Martorell Sampol, L.; Rodriguez, B.; Pascual-Castroviejo, I.; Teber, S.; Anlar, B.; Comu, S.; Karaca, E.; Kayserili, H.; Yüksel, A.; Akcakus, M.; Al Gazali, L.; Sztriha, L.; Nicholl, D.; Woods, C. G.; Bennett, C.; Hurst, J.; Sheridan, E.; Barnicoat, A.; Hennekam, R.; Lees, M.; Blair, E.; Bernes, S.; Sanchez, H.; Clark, A. E.; DeMarco, E.; Donahue, C.; Sherr, E.; Hahn, J.; Sanger, T. D.; Gallager, T. E.; Dobyns, W. B.; Daugherty, C.; Krishnamoorthy, K. S.; Sarco, D.; Walsh, C. A.; McKanna, T.; Milisa, J.; Chung, W. K.; de Vivo, D. C.; Raynes, H.; Schubert, R.; Seward, A.; Brooks, D. G.; Goldstein, A.; Caldwell, J.; Finsecke, E.; Maria, B. L.; Holden, K.; Cruse, R. P.; Swoboda, K. J.; Viskochil, D.

    2009-01-01

    Ciliopathies are an expanding group of rare conditions characterized by multiorgan involvement, that are caused by mutations in genes encoding for proteins of the primary cilium or its apparatus. Among these genes, CEP290 bears an intriguing allelic spectrum, being commonly mutated in Joubert

  18. Ultraviolet-induced reversion of cyc1 alleles in radiation-sensitive strains of yeast. III. rev 3 mutant strains

    International Nuclear Information System (INIS)

    Lawrence, C.W.; Crhistensen, R.B.

    1979-01-01

    The role of rev3 gene function in uv-induced mutagenesis in the yeast Saccharomyces cerevisiae has been examined by determining the reversion of 12 well-defined cyc1 mutations in diploid strains homozygous for the rev3-1 or rev3-3 allale. The 12 cyc1 alleles include one ochre, one amber, four initiation, two proline missense, and four frameshift mutations. We find that the rev3 mutations reduce the frequency of UV-induced reversion of all of the cyc1 alleles, though different classes of alleles respond to a different extent. These results imply that the rev3 gene function is required for the production of a wide variety of mutational events, though probably not all, and show that each of the three rev loci have different mutational phenotypes. Such diverse phenotypes are not predicted by the unitary model for bacterial mutagenes, suggesting that this is at best an incomplete description of eukaryotic mutagenesis

  19. A pseudodeficiency allele common in non-Jewish Tay-Sachs carriers: Implications for carrier screening

    Energy Technology Data Exchange (ETDEWEB)

    Triggs-Raine, B.L.; Akerman, B.R.; Gravel, R.A. (McGill Univ.-Montreal Children' s Hospital Research Institute, Montreal, Quebec (Canada)); Mules, E.H.; Thomas, G.H.; Dowling, C.E. (Johns Hopkins School of Medicine, Baltimore, MD (United States)); Kaback, M.M.; Lim-Steele, J.S.T. (Univ. of California, San Diego, CA (United States)); Natowicz, M.R. (Eunice Kennedy Shriver Center for Mental Retardation, Waltham, MA (United States)); Grebner, E.E. (Thomas Jefferson Univ., Philadelphia, PA (United States)); Navon, R.R. (Tel-Aviv Univ., Kfar-Sava (Israel)); Welch, J.P. (Dalhousie Univ., Halifax, Nova, Scotia (Canada)); Greenberg, C.R. (Univ. of Manitoba, Winnipeg (Canada))

    1992-10-01

    Deficiency of [beta]-hexosaminidase A (Hex A) activity typically results in Tay-Sachs disease. However, healthy subjects found to be deficient in Hex A activity (i.e., pseudodeficient) by means of in vitro biochemical tests have been described. The authors analyzed the HEXA gene of one pseudodeficient subject and identified both a C[sub 739]-to-T substitution that changes Arg[sub 247][yields]Trp on one allele and a previously identified Tay-Sachs disease mutation of the second allele. Six additional pseudodeficient subjects were found to have the C[sub 739]-to-T but for none of 36 Jewish enzyme-defined carries who did not have one of three known mutations common to this group. The C[sub 739]-to-T allele, together with a [open quotes]true[close quotes] Tay-Sachs disease allele, causes Hex A pseudodeficiency. Given both the large proportion of non-Jewish carriers with this allele and that standard biochemical screening cannot differentiate between heterozygotes for the C[sub 739]-to-T mutations and Tay-Sachs disease carriers, DNA testing for this mutation in at-risk couples is essential. This could prevent unnecessary or incorrect prenatal diagnoses. 40 refs., 3 figs., 4 tabs.

  20. CYP3A4 allelic variants with amino acid substitutions in exons 7 and 12: evidence for an allelic variant with altered catalytic activity.

    Science.gov (United States)

    Sata, F; Sapone, A; Elizondo, G; Stocker, P; Miller, V P; Zheng, W; Raunio, H; Crespi, C L; Gonzalez, F J

    2000-01-01

    To determine the existence of mutant and variant CgammaP3A4 alleles in three racial groups and to assess functions of the variant alleles by complementary deoxyribonucleic acid (cDNA) expression. A bacterial artificial chromosome that contains the complete CgammaP3A4 gene was isolated and the exons and surrounding introns were directly sequenced to develop primers to polymerase chain reaction (PCR) amplify and sequence the gene from lymphocyte DNA. DNA samples from Chinese, black, and white subjects were screened. Mutating the affected amino acid in the wild-type cDNA and expressing the variant enzyme with use of the baculovirus system was used to functionally evaluate the variant allele having a missense mutation. To investigate the existence of mutant and variant CgammaP3A4 alleles in humans, all 13 exons and the 5'-flanking region of the human CgammaP3A4 gene in three racial groups were sequenced and four alleles were identified. An A-->G point mutation in the 5'-flanking region of the human CgammaP3A4 gene, designated CgammaP3A4*1B, was found in the three different racial groups. The frequency of this allele in a white population was 4.2%, whereas it was 66.7% in black subjects. The CgammaP3A4*1B allele was not found in Chinese subjects. A second variant allele, designated CgammaP3A4*2, having a Ser222Pro change, was found at a frequency of 2.7% in the white population and was absent in the black subjects and Chinese subjects analyzed. Baculovirus-directed cDNA expression revealed that the CYP3A4*2 P450 had a lower intrinsic clearance for the CYP3A4 substrate nifedipine compared with the wild-type enzyme but was not significantly different from the wild-type enzyme for testosterone 6beta-hydroxylation. Another rare allele, designated CgammaP3A4*3, was found in a single Chinese subject who had a Met445Thr change in the conserved heme-binding region of the P450. These are the first examples of potential function polymorphisms resulting from missense mutations in

  1. Systematic Functional Interrogation of Rare Cancer Variants Identifies Oncogenic Alleles | Office of Cancer Genomics

    Science.gov (United States)

    Cancer genome characterization efforts now provide an initial view of the somatic alterations in primary tumors. However, most point mutations occur at low frequency, and the function of these alleles remains undefined. We have developed a scalable systematic approach to interrogate the function of cancer-associated gene variants. We subjected 474 mutant alleles curated from 5,338 tumors to pooled in vivo tumor formation assays and gene expression profiling. We identified 12 transforming alleles, including two in genes (PIK3CB, POT1) that have not been shown to be tumorigenic.

  2. Allele Age Under Non-Classical Assumptions is Clarified by an Exact Computational Markov Chain Approach.

    Science.gov (United States)

    De Sanctis, Bianca; Krukov, Ivan; de Koning, A P Jason

    2017-09-19

    Determination of the age of an allele based on its population frequency is a well-studied problem in population genetics, for which a variety of approximations have been proposed. We present a new result that, surprisingly, allows the expectation and variance of allele age to be computed exactly (within machine precision) for any finite absorbing Markov chain model in a matter of seconds. This approach makes none of the classical assumptions (e.g., weak selection, reversibility, infinite sites), exploits modern sparse linear algebra techniques, integrates over all sample paths, and is rapidly computable for Wright-Fisher populations up to N e  = 100,000. With this approach, we study the joint effect of recurrent mutation, dominance, and selection, and demonstrate new examples of "selective strolls" where the classical symmetry of allele age with respect to selection is violated by weakly selected alleles that are older than neutral alleles at the same frequency. We also show evidence for a strong age imbalance, where rare deleterious alleles are expected to be substantially older than advantageous alleles observed at the same frequency when population-scaled mutation rates are large. These results highlight the under-appreciated utility of computational methods for the direct analysis of Markov chain models in population genetics.

  3. The geographic spread of the CCR5 Delta32 HIV-resistance allele.

    Directory of Open Access Journals (Sweden)

    John Novembre

    2005-11-01

    Full Text Available The Delta32 mutation at the CCR5 locus is a well-studied example of natural selection acting in humans. The mutation is found principally in Europe and western Asia, with higher frequencies generally in the north. Homozygous carriers of the Delta32 mutation are resistant to HIV-1 infection because the mutation prevents functional expression of the CCR5 chemokine receptor normally used by HIV-1 to enter CD4+ T cells. HIV has emerged only recently, but population genetic data strongly suggest Delta32 has been under intense selection for much of its evolutionary history. To understand how selection and dispersal have interacted during the history of the Delta32 allele, we implemented a spatially explicit model of the spread of Delta32. The model includes the effects of sampling, which we show can give rise to local peaks in observed allele frequencies. In addition, we show that with modest gradients in selection intensity, the origin of the Delta32 allele may be relatively far from the current areas of highest allele frequency. The geographic distribution of the Delta32 allele is consistent with previous reports of a strong selective advantage (>10% for Delta32 carriers and of dispersal over relatively long distances (>100 km/generation. When selection is assumed to be uniform across Europe and western Asia, we find support for a northern European origin and long-range dispersal consistent with the Viking-mediated dispersal of Delta32 proposed by G. Lucotte and G. Mercier. However, when we allow for gradients in selection intensity, we estimate the origin to be outside of northern Europe and selection intensities to be strongest in the northwest. Our results describe the evolutionary history of the Delta32 allele and establish a general methodology for studying the geographic distribution of selected alleles.

  4. Analysis of FBN1 allele expression by dermal fibroblasts from Marfan syndrome patients

    Energy Technology Data Exchange (ETDEWEB)

    Putman, E.A.; Cao, S.N.; Milewicz, D.M. [Univ. of Texas Medical School, Houston, TX (United States)

    1994-09-01

    Screening for mutations in the FBN1 cDNA from Marfan patient cell strains has detected mutations in only 10-15% of patients. In an attempt to explain this poor detection rate, we examined FBN1 allele expression and fibrillin synthesis by 26 cell strains from Marfan patients. DNA from the patients and 10 controls was assessed for the presence of a polymorphic Rsa I restriction site in the 3{prime} untranslated region of the FBN1 gene. Twelve of 26 patient and 5 of 10 control DNAs were heterozygous. Fibroblast RNA from the heterozygous cell strains was reverse-transcribed and subsequently PCR amplified using a [{sup 32}P]-labelled primer, digested with Rsa I and analyzed. Although 3 samples showed no transcript from one allele by ethidium bromide staining, a Betagen scanner detected low levels (10-15%) of that allele. In addition, there was unequal expression of the two alleles in three other patients; for example, only 30% expression from one allele. The remaining patients and the controls had equal expression of each allele. Fibrillin protein synthesis by fibroblasts from these heterozygous patients was also examined. After a 30 minute pulse with [{sup 35}S]-cysteine, cell lysates were collected and proteins analyzed by SDS-PAGE. The amount of fibrillin produced relative to a reference protein was determined using a Betagen scanner. Fibrillin protein synthesis was reduced in 2 of the 3 patients with very low RNA production from one of the FBN1 alleles. All other Marfan and control cell strains showed normal amounts of fibrillin synthesized. The low expression levels from one allele may contribute to, but not fully account for, the low detection rate of FBN1 mutations. Interestingly, protein synthesis levels were not affected in 4 of 6 cell strains demonstrating low levels of RNA expression.

  5. Molecular characterization of both alleles in an unusual Tay-Sachs disease BI variant

    Energy Technology Data Exchange (ETDEWEB)

    Coulter-Mackie, M.B. (Univ. of Western Ontario, London (Canada) Child Health Research Institute, Children' s Hospital of Western Ontario, London (Canada) Child Parent Resource Institute, London, Ontario (Canada))

    1994-06-01

    In a recent report, the authors described an exon 6 mutation in a Tay-Sachs B1 variant patient, first reported by Gordon et al. (1988), who displayed a typical B1 variant biochemical phenotype - i.e., (a) significant levels of hexosaminidase A (Hex A) activity in an assay with a neutral synthetic substrate, 4-methylumbelliferyl-[beta]-N-acetylglucosamide, and (b) <2% of control Hex A in a test on the sulfated substrate, 4-methylumbelliferyl-[beta]-N-acetylglucosamide-6-sulfate. The patient was found to carry a double mutation (G[sub 574][yields]C [val[sub 192][yields]leu] and G[sub 598][yields]A [val[sub 200][yields]met]) inherited from her mother. Only the 574 mutation produced a deleterious effect on Hex A activity in transfected COS0-1 cells, producing a B1 variant biochemical phenotype. The paternal allele apparently caused decreased abundance of mRNA, since no candidate paternal mutations were found in cloned reverse transcription-PCR (RT-PCR) products in the reported study. The biochemical phenotype of the original patient and the properties of the cDNA carrying the G[sub 574] [yields] C mutation in transient expression studies were compatible with a B1 variant mutation. The possibility remained that there might be some contribution from the paternal allele to the patient's phenotype. However, the paternal allele produces relatively low yields of a largely mis-spliced mRNA whose product would not be functional. Therefore, the G[sub 574] [yields] C (val[yields]leu) mutation in the maternal allele is clearly confirmed as a B1 variant mutation with all the ramifications for the substrate binding site and/or catalytic center that this implies.

  6. An Updated Collection of Sequence Barcoded Temperature-Sensitive Alleles of Yeast Essential Genes.

    Science.gov (United States)

    Kofoed, Megan; Milbury, Karissa L; Chiang, Jennifer H; Sinha, Sunita; Ben-Aroya, Shay; Giaever, Guri; Nislow, Corey; Hieter, Philip; Stirling, Peter C

    2015-07-14

    Systematic analyses of essential gene function using mutant collections in Saccharomyces cerevisiae have been conducted using collections of heterozygous diploids, promoter shut-off alleles, through alleles with destabilized mRNA, destabilized protein, or bearing mutations that lead to a temperature-sensitive (ts) phenotype. We previously described a method for construction of barcoded ts alleles in a systematic fashion. Here we report the completion of this collection of alleles covering 600 essential yeast genes. This resource covers a larger gene repertoire than previous collections and provides a complementary set of strains suitable for single gene and genomic analyses. We use deep sequencing to characterize the amino acid changes leading to the ts phenotype in half of the alleles. We also use high-throughput approaches to describe the relative ts behavior of the alleles. Finally, we demonstrate the experimental usefulness of the collection in a high-content, functional genomic screen for ts alleles that increase spontaneous P-body formation. By increasing the number of alleles and improving the annotation, this ts collection will serve as a community resource for probing new aspects of biology for essential yeast genes. Copyright © 2015 Kofoed et al.

  7. Assessment of the myostatin Q204X allele using an allelic discrimination assay

    OpenAIRE

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

    2006-01-01

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

  8. Ankyrin-1 Gene Exhibits Allelic Heterogeneity in Conferring Protection Against Malaria

    Directory of Open Access Journals (Sweden)

    Hong Ming Huang

    2017-09-01

    Full Text Available Allelic heterogeneity is a common phenomenon where a gene exhibits a different phenotype depending on the nature of its genetic mutations. In the context of genes affecting malaria susceptibility, it allowed us to explore and understand the intricate host–parasite interactions during malaria infections. In this study, we described a gene encoding erythrocytic ankyrin-1 (Ank-1 which exhibits allelic-dependent heterogeneous phenotypes during malaria infections. We conducted an ENU mutagenesis screen on mice and identified two Ank-1 mutations, one resulting in an amino acid substitution (MRI95845, and the other a truncated Ank-1 protein (MRI96570. Both mutations caused hereditary spherocytosis-like phenotypes and confer differing protection against Plasmodium chabaudi infections. Upon further examination, the Ank-1(MRI96570 mutation was found to inhibit intraerythrocytic parasite maturation, whereas Ank-1(MRI95845 caused increased bystander erythrocyte clearance during infection. This is the first description of allelic heterogeneity in ankyrin-1 from the direct comparison between two Ank-1 mutations. Despite the lack of direct evidence from population studies, this data further supported the protective roles of ankyrin-1 mutations in conferring malaria protection. This study also emphasized the importance of such phenomena in achieving a better understanding of host–parasite interactions, which could be the basis of future studies.

  9. Characterization of a mutation commonly associated with persistent stuttering: evidence for a founder mutation

    Science.gov (United States)

    Fedyna, Alison; Drayna, Dennis; Kang, Changsoo

    2010-01-01

    Stuttering is a disorder which affects the fluency of speech. It has been shown to have high heritability, and has recently been linked to mutations in the GNPTAB gene. One such mutation, Glu1200Lys, has been repeatedly observed in unrelated families and individual cases. Eight unrelated individuals carrying this mutation were analyzed in an effort to distinguish whether these arise from repeated mutation at the same site, or whether they represent a founder mutation with a single origin. Results show that all 12 chromosomes carrying this mutation share a common haplotype in this region, indicating it is a founder mutation. Further analysis estimated the age of this allele to be ~572 generations. Construction of a cladogram tracing the mutation through our study sample also supports the founder mutation hypothesis. PMID:20944643

  10. Analysis of average standardized SSR allele size supports domestication of soybean along the Yellow River

    NARCIS (Netherlands)

    Li, Y.H.; Zhang, C.; Smulders, M.J.M.; Li, W.; Ma, Y.S.; Xu, Qu; Chang, R.Z.; Qiu, Li-Juan

    2013-01-01

    Soybean (Glycine max) was domesticated in China from its wild progenitor G. soja. The geographic region of domestication is, however, not exactly known. Here we employed the directional evolution of SSR (microsatellite) repeats (which mutate preferentially into longer alleles) to analyze the

  11. Autosomal dominant polycystic kidney disease in a family with mosaicism and hypomorphic allele.

    Science.gov (United States)

    Reiterová, Jana; Štekrová, Jitka; Merta, Miroslav; Kotlas, Jaroslav; Elišáková, Veronika; Lněnička, Petr; Korabečná, Marie; Kohoutová, Milada; Tesař, Vladimír

    2013-03-15

    Autosomal dominant polycystic kidney disease (ADPKD) is the most common form of inherited kidney disease that results in renal failure. ADPKD is a systemic disorder with cysts and connective tissue abnormalities involving many organs. ADPKD caused by mutations in PKD1 gene is significantly more severe than the cases caused by PKD2 gene mutations. The large intra-familial variability of ADPKD highlights a role for genetic background. Here we report a case of ADPKD family initially appearing unlinked to the PKD1 or PKD2 loci and the influence of mosaicism and hypomorphic allele on the variability of the clinical course of the disease. A grandmother with the PKD1 gene mutation in mosaicism (p.Val1105ArgfsX4) and with mild clinical course of ADPKD (end stage renal failure at the age of 77) seemed to have ADPKD because of PKD2 gene mutation. On the other hand, her grandson had a severe clinical course (end stage renal disease at the age of 45) in spite of the early treatment of mild hypertension. There was found by mutational analysis of PKD genes that the severe clinical course was caused by PKD1 gene frameshifting mutation inherited from his father and mildly affected grandmother in combination with inherited hypomorphic PKD1 allele with described missense mutation (p.Thr2250Met) from his clinically healthy mother. The sister with two cysts and with PKD1 hypomorphic allele became the kidney donor to her severely affected brother. We present the first case of ADPKD with the influence of mosaicism and hypomorphic allele of the PKD1 gene on clinical course of ADPKD in one family. Moreover, this report illustrates the role of molecular genetic testing in assessing young related kidney donors for patients with ADPKD.

  12. Germline minisatellite mutations in workers occupationally exposed to radiation at the Sellafield nuclear facility

    International Nuclear Information System (INIS)

    Tawn, E Janet; Curwen, Gillian B; Rees, Gwen S; Jonas, Patricia

    2015-01-01

    Germline minisatellite mutation rates were investigated in male workers occupationally exposed to radiation at the Sellafield nuclear facility. DNA samples from 160 families with 255 offspring were analysed for mutations at eight hypervariable minisatellite loci (B6.7, CEB1, CEB15, CEB25, CEB36, MS1, MS31, MS32) by Southern hybridisation. No significant difference was observed between the paternal mutation rate of 5.0% (37 mutations in 736 alleles) for control fathers with a mean preconceptional testicular dose of 9 mSv and that of 5.8% (66 in 1137 alleles) for exposed fathers with a mean preconceptional testicular dose of 194 mSv. Subgrouping the exposed fathers into two dose groups with means of 111 mSv and 274 mSv revealed paternal mutation rates of 6.0% (32 mutations in 536 alleles) and 5.7% (34 mutations in 601 alleles), respectively, neither of which was significantly different in comparisons with the rate for the control fathers. Maternal mutation rates of 1.6% (12 mutations in 742 alleles) for the partners of control fathers and 1.7% (19 mutations in 1133 alleles) for partners of exposed fathers were not significantly different. This study provides evidence that paternal preconceptional occupational radiation exposure does not increase the germline minisatellite mutation rate and therefore refutes suggestions that such exposure could result in a destabilisation of the germline that can be passed on to future generations. (paper)

  13. The number of self-incompatibility alleles in a finite, subdivided population

    DEFF Research Database (Denmark)

    Schierup, M H

    1998-01-01

    The actual and effective number of gametophytic self-incompatibility alleles maintained at mutation-drift-selection equilibrium in a finite population subdivided as in the island model is investigated by stochastic simulations. The existing theory founded by Wright predicts that for a given...... population size the number of alleles maintained increases monotonically with decreasing migration as is the case for neutral alleles. The simulation results here show that this is not true. At migration rates above Nm = 0.01-0.1, the actual and effective number of alleles is lower than for an undivided...... of individuals in the population but it underestimates the neutral effective size of the subdivided population. Udgivelsesdato: 1998-Jun...

  14. Revertant mutation releases confined lethal mutation, opening Pandora's box: a novel genetic pathogenesis.

    Directory of Open Access Journals (Sweden)

    Yasushi Ogawa

    2014-05-01

    Full Text Available When two mutations, one dominant pathogenic and the other "confining" nonsense, coexist in the same allele, theoretically, reversion of the latter may elicit a disease, like the opening of Pandora's box. However, cases of this hypothetical pathogenic mechanism have never been reported. We describe a lethal form of keratitis-ichthyosis-deafness (KID syndrome caused by the reversion of the GJB2 nonsense mutation p.Tyr136X that would otherwise have confined the effect of another dominant lethal mutation, p.Gly45Glu, in the same allele. The patient's mother had the identical misssense mutation which was confined by the nonsense mutation. The biological relationship between the parents and the child was confirmed by genotyping of 15 short tandem repeat loci. Haplotype analysis using 40 SNPs spanning the >39 kbp region surrounding the GJB2 gene and an extended SNP microarray analysis spanning 83,483 SNPs throughout chromosome 13 in the family showed that an allelic recombination event involving the maternal allele carrying the mutations generated the pathogenic allele unique to the patient, although the possibility of coincidental accumulation of spontaneous point mutations cannot be completely excluded. Previous reports and our mutation screening support that p.Gly45Glu is in complete linkage disequilibrium with p.Tyr136X in the Japanese population. Estimated from statisitics in the literature, there may be approximately 11,000 p.Gly45Glu carriers in the Japanese population who have this second-site confining mutation, which acts as natural genetic protection from the lethal disease. The reversion-triggered onset of the disesase shown in this study is a previously unreported genetic pathogenesis based on Mendelian inheritance.

  15. Sensory Gating and Alpha-7 Nicotinic Receptor Gene Allelic Variants in Schizoaffective Disorder, Bipolar Type

    Science.gov (United States)

    Martin, Laura F.; Leonard, Sherry; Hall, Mei-Hua; Tregellas, Jason R.; Freedman, Robert; Olincy, Ann

    2011-01-01

    Objectives Single nucleotide allelic variants in the promoter region of the chromosome 15 alpha-7 acetylcholine nicotinic receptor gene (CHRNA7) are associated with both schizophrenia and the P50 auditory evoked potential sensory gating deficit. The purpose of this study was to determine if CHRNA7 promoter allelic variants are also associated with abnormal P50 ratios in persons with schizoaffective disorder, bipolar type. Methods P50 auditory evoked potentials were recorded in a paired stimulus paradigm in 17 subjects with schizoaffective disorder, bipolar type. The P50 test to conditioning ratio was used as the measure of sensory gating. Mutation screening of the CHRNA7 promoter region was performed on the subjects’ DNA samples. Comparisons to previously obtained data from persons with schizophrenia and controls were made. Results Subjects with schizophrenia, regardless of allele status, had an abnormal mean P50 ratio. Subjects with schizoaffective disorder, bipolar type and a variant allele had an abnormal mean P50 ratio, whereas those schizoaffective subjects with the common alleles had a normal mean P50 ratio. Normal control subjects had a normal mean ratio, but controls with variant alleles had higher P50 ratios. Conclusions In persons with bipolar type schizoaffective disorder, CHRNA7 promoter region allelic variants are linked to the capacity to inhibit the P50 auditory evoked potential and thus are associated with a type of illness genetically and biologically more similar to schizophrenia. PMID:17192894

  16. Characterization of a Novel MMS-Sensitive Allele of Schizosaccharomyces pombe mcm4+

    Science.gov (United States)

    Ranatunga, Nimna S.; Forsburg, Susan L.

    2016-01-01

    The minichromosome maintenance (MCM) complex is the conserved helicase motor of the eukaryotic replication fork. Mutations in the Mcm4 subunit are associated with replication stress and double strand breaks in multiple systems. In this work, we characterize a new temperature-sensitive allele of Schizosaccharomyces pombe mcm4+. Uniquely among known mcm4 alleles, this mutation causes sensitivity to the alkylation damaging agent methyl methanesulfonate (MMS). Even in the absence of treatment or temperature shift, mcm4-c106 cells show increased repair foci of RPA and Rad52, and require the damage checkpoint for viability, indicating genome stress. The mcm4-c106 mutant is synthetically lethal with mutations disrupting fork protection complex (FPC) proteins Swi1 and Swi3. Surprisingly, we found that the deletion of rif1+ suppressed the MMS-sensitive phenotype without affecting temperature sensitivity. Together, these data suggest that mcm4-c106 destabilizes replisome structure. PMID:27473316

  17. Radiation-induced mutations in mammals

    International Nuclear Information System (INIS)

    Ehling, U.H.

    1993-01-01

    The aims of the proposed project are to provide a better basis for extrapolation of animal data to man. Genetic endpoint, strain and species comparisons are made, which will provide critical experimental data regarding strategies in extrapolating laboratory animal data to man. Experiments were conducted to systematically compare the spontaneous and radiation-induced mutation rates for recessive specific-locus, dominant cataract and enzyme activity alleles in the mouse as well as a comparison of the mutation rate in the mouse and hamster for dominant cataract and enzyme activity alleles. The comparison of the radiation-dose response for recessive specific-locus and dominant cataract mutations are extended. Selected mutations are characterized at the genetic, biochemical and molecular levels. (R.P.) 5 refs., 3 tabs

  18. Random Evolutionary Dynamics Driven by Fitness and House-of-Cards Mutations: Sampling Formulae

    Science.gov (United States)

    Huillet, Thierry E.

    2017-07-01

    We first revisit the multi-allelic mutation-fitness balance problem, especially when mutations obey a house of cards condition, where the discrete-time deterministic evolutionary dynamics of the allelic frequencies derives from a Shahshahani potential. We then consider multi-allelic Wright-Fisher stochastic models whose deviation to neutrality is from the Shahshahani mutation/selection potential. We next focus on the weak selection, weak mutation cases and, making use of a Gamma calculus, we compute the normalizing partition functions of the invariant probability densities appearing in their Wright-Fisher diffusive approximations. Using these results, generalized Ewens sampling formulae (ESF) from the equilibrium distributions are derived. We start treating the ESF in the mixed mutation/selection potential case and then we restrict ourselves to the ESF in the simpler house-of-cards mutations only situation. We also address some issues concerning sampling problems from infinitely-many alleles weak limits.

  19. Alleles versus genotypes: Genetic interactions and the dynamics of selection in sexual populations

    Science.gov (United States)

    Neher, Richard

    2010-03-01

    Physical interactions between amino-acids are essential for protein structure and activity, while protein-protein interactions and regulatory interactions are central to cellular function. As a consequence of these interactions, the combined effect of two mutations can differ from the sum of the individual effects of the mutations. This phenomenon of genetic interaction is known as epistasis. However, the importance of epistasis and its effects on evolutionary dynamics are poorly understood, especially in sexual populations where recombination breaks up existing combinations of alleles to produce new ones. Here, we present a computational model of selection dynamics involving many epistatic loci in a recombining population. We demonstrate that a large number of polymorphic interacting loci can, despite frequent recombination, exhibit cooperative behavior that locks alleles into favorable genotypes leading to a population consisting of a set of competing clones. As the recombination rate exceeds a certain critical value this ``genotype selection'' phase disappears in an abrupt transition giving way to ``allele selection'' - the phase where different loci are only weakly correlated as expected in sexually reproducing populations. Clustering of interacting sets of genes on a chromosome leads to the emergence of an intermediate regime, where localized blocks of cooperating alleles lock into genetic modules. Large populations attain highest fitness at a recombination rate just below critical, suggesting that natural selection might tune recombination rates to balance the beneficial aspect of exploration of genotype space with the breaking up of synergistic allele combinations.

  20. Tumor transcriptome sequencing reveals allelic expression imbalances associated with copy number alterations.

    Directory of Open Access Journals (Sweden)

    Brian B Tuch

    Full Text Available Due to growing throughput and shrinking cost, massively parallel sequencing is rapidly becoming an attractive alternative to microarrays for the genome-wide study of gene expression and copy number alterations in primary tumors. The sequencing of transcripts (RNA-Seq should offer several advantages over microarray-based methods, including the ability to detect somatic mutations and accurately measure allele-specific expression. To investigate these advantages we have applied a novel, strand-specific RNA-Seq method to tumors and matched normal tissue from three patients with oral squamous cell carcinomas. Additionally, to better understand the genomic determinants of the gene expression changes observed, we have sequenced the tumor and normal genomes of one of these patients. We demonstrate here that our RNA-Seq method accurately measures allelic imbalance and that measurement on the genome-wide scale yields novel insights into cancer etiology. As expected, the set of genes differentially expressed in the tumors is enriched for cell adhesion and differentiation functions, but, unexpectedly, the set of allelically imbalanced genes is also enriched for these same cancer-related functions. By comparing the transcriptomic perturbations observed in one patient to his underlying normal and tumor genomes, we find that allelic imbalance in the tumor is associated with copy number mutations and that copy number mutations are, in turn, strongly associated with changes in transcript abundance. These results support a model in which allele-specific deletions and duplications drive allele-specific changes in gene expression in the developing tumor.

  1. Distribution of the PKU mutation 165T in Spain and Latin America

    Energy Technology Data Exchange (ETDEWEB)

    Perez, B.; deLucca, M.; Desviat, L.R. [UAM-CSIC, Madrid (Spain)] [and others

    1994-09-01

    The 165T mutation is the second most common mutation in the Spanish PKU patients. In order to provide some additional data about the origin of this mutation, we have analyzed 452 PKU alleles from all regions of Spain. The mutation was found in 9% of alleles. We have found a South-North gradient with a highest frequency in the South and the lowest in the North. In the North-West regions (which has the greatest Celtic influence in Spain) the frequency was 7%. The chromosomes bearing this mutation contained the 8 repeat VNTR allele, as has been described in other populations. In view of these results, we suggest an origin other than Celtic for this mutation. On the other hand, we have analyzed 406 PKU alleles from five Latin American countries, 158 from Brazil, 170 from Chile, 56 from Argentina, 14 from Mexico and 8 from Venezuela. Unlike the results of the IVS10 mutation, 165T is present in Latin America with a low frequency. The results show that this mutation is rare in Chile (1%) and is absent in the chromosomes analyzed from Argentina, Mexico and Venezuela. Only in Brazil has this mutation been found in 5% of the alleles. Up to now, Spain is the only Mediterranean country where this mutation is present with a relatively high frequency. This mutation has been detected in the Portuguese patients and would also have migrated to Brazil.

  2. Molecular methods for the detection of mutations.

    Science.gov (United States)

    Monteiro, C; Marcelino, L A; Conde, A R; Saraiva, C; Giphart-Gassler, M; De Nooij-van Dalen, A G; Van Buuren-van Seggelen, V; Van der Keur, M; May, C A; Cole, J; Lehmann, A R; Steinsgrimsdottir, H; Beare, D; Capulas, E; Armour, J A

    2000-01-01

    We report the results of a collaborative study aimed at developing reliable, direct assays for mutation in human cells. The project used common lymphoblastoid cell lines, both with and without mutagen treatment, as a shared resource to validate the development of new molecular methods for the detection of low-level mutations in the presence of a large excess of normal alleles. As the "gold standard, " hprt mutation frequencies were also measured on the same samples. The methods under development included i) the restriction site mutation (RSM) assay, in which mutations lead to the destruction of a restriction site; ii) minisatellite length-change mutation, in which mutations lead to alleles containing new numbers of tandem repeat units; iii) loss of heterozygosity for HLA epitopes, in which antibodies can be used to direct selection for mutant cells; iv) multiple fluorescence-based long linker arm nucleotides assay (mf-LLA) technology, for the detection of substitutional mutations; v) detection of alterations in the TP53 locus using a (CA) array as the target for the screening; and vi) PCR analysis of lymphocytes for the presence of the BCL2 t(14:18) translocation. The relative merits of these molecular methods are discussed, and a comparison made with more "traditional" methods.

  3. Allelic Variation of Cytochrome P450s Drives Resistance to Bednet Insecticides in a Major Malaria Vector.

    Science.gov (United States)

    Ibrahim, Sulaiman S; Riveron, Jacob M; Bibby, Jaclyn; Irving, Helen; Yunta, Cristina; Paine, Mark J I; Wondji, Charles S

    2015-10-01

    Scale up of Long Lasting Insecticide Nets (LLINs) has massively contributed to reduce malaria mortality across Africa. However, resistance to pyrethroid insecticides in malaria vectors threatens its continued effectiveness. Deciphering the detailed molecular basis of such resistance and designing diagnostic tools is critical to implement suitable resistance management strategies. Here, we demonstrated that allelic variation in two cytochrome P450 genes is the most important driver of pyrethroid resistance in the major African malaria vector Anopheles funestus and detected key mutations controlling this resistance. An Africa-wide polymorphism analysis of the duplicated genes CYP6P9a and CYP6P9b revealed that both genes are directionally selected with alleles segregating according to resistance phenotypes. Modelling and docking simulations predicted that resistant alleles were better metabolizers of pyrethroids than susceptible alleles. Metabolism assays performed with recombinant enzymes of various alleles confirmed that alleles from resistant mosquitoes had significantly higher activities toward pyrethroids. Additionally, transgenic expression in Drosophila showed that flies expressing resistant alleles of both genes were significantly more resistant to pyrethroids compared with those expressing the susceptible alleles, indicating that allelic variation is the key resistance mechanism. Furthermore, site-directed mutagenesis and functional analyses demonstrated that three amino acid changes (Val109Ile, Asp335Glu and Asn384Ser) from the resistant allele of CYP6P9b were key pyrethroid resistance mutations inducing high metabolic efficiency. The detection of these first DNA markers of metabolic resistance to pyrethroids allows the design of DNA-based diagnostic tools to detect and track resistance associated with bednets scale up, which will improve the design of evidence-based resistance management strategies.

  4. Inference of directional selection and mutation parameters assuming equilibrium.

    Science.gov (United States)

    Vogl, Claus; Bergman, Juraj

    2015-12-01

    In a classical study, Wright (1931) proposed a model for the evolution of a biallelic locus under the influence of mutation, directional selection and drift. He derived the equilibrium distribution of the allelic proportion conditional on the scaled mutation rate, the mutation bias and the scaled strength of directional selection. The equilibrium distribution can be used for inference of these parameters with genome-wide datasets of "site frequency spectra" (SFS). Assuming that the scaled mutation rate is low, Wright's model can be approximated by a boundary-mutation model, where mutations are introduced into the population exclusively from sites fixed for the preferred or unpreferred allelic states. With the boundary-mutation model, inference can be partitioned: (i) the shape of the SFS distribution within the polymorphic region is determined by random drift and directional selection, but not by the mutation parameters, such that inference of the selection parameter relies exclusively on the polymorphic sites in the SFS; (ii) the mutation parameters can be inferred from the amount of polymorphic and monomorphic preferred and unpreferred alleles, conditional on the selection parameter. Herein, we derive maximum likelihood estimators for the mutation and selection parameters in equilibrium and apply the method to simulated SFS data as well as empirical data from a Madagascar population of Drosophila simulans. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Mutations in galactosemia

    Energy Technology Data Exchange (ETDEWEB)

    Reichardt, J.K.V. [Univ. of Southern California School of Medicine, Los Angeles, CA (United States)

    1995-10-01

    This Letter raises four issues concerning two papers on galactosemia published in the March 1995 of the Journal. First, table 2 in the paper by Elsas et al. incorrectly attributes seven galactose-l-phosphate uridyl transferase (GALT) mutations (S135L, L195P, K285N, N314D, R333W, R333G, and K334R). The table also fails to mention that others have reported the same two findings attributed to {open_quotes}Leslie et al.; Elsas et al. and in press{close_quotes} and {open_quotes}Leslie et al.; Elsas et al.{close_quotes} The first finding on the prevalence of the Q188R galactosemia mutation in the G/G Caucasian population has also been described by Ng et al., and the second finding on the correlation of the N314D GALT mutation with the Duarte variant was reported by Lin et al. Second, Elsas et al. suggest that the E203K and N314D mutations may {open_quotes}produce intra-allelic complementation when in cis{close_quotes}. This speculation is supported by the activity data of individual III-2 but is inconsistent with the activities of three other individuals I-1, II-1, and III-1 of the same pedigree. The GALT activity measured in these three individuals suggests a dominant negative effect of E203K in E203K-N314D chromosomes, since they all have less than normal activity. Thus, the preponderance of the data in this paper is at odds with the authors speculation. It is worth recalling that Lin et al. also identified four N314D GALT mutations on 95 galactosemic chromosomes examined. A similar situation also appears to be the case in proband III-1 (with genotype E203K-N314D/IVSC) in the Elsas et al. paper. 9 refs.

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

    Science.gov (United States)

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

    2018-01-01

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

  7. Filaggrin compound heterozygous patients carry mutations in trans position

    DEFF Research Database (Denmark)

    Carlsen, Berit C; Meldgaard, Michael; Johansen, Jeanne D

    2013-01-01

    by means of allele-specific PCR amplification and analysis of PCR products by agarose gel electrophoresis. All R501X/2282del4 compound heterozygous samples collected over a 4-year period of routine FLG mutation testing were investigated. In total, 37 samples were tested. All thirty-seven R501X/2282del4......More than 40 null mutations in the filaggrin (FLG) gene are described. It is therefore possible to find two different null mutations in one individual (compound heterozygosity). It has been generally perceived that homozygous and compound heterozygous individuals were genotypically comparable......; however, this has not been scientifically investigated. Two different FLG null mutations in the same individual may be in trans position, meaning that each mutation locates to a different allele functionally equivalent to homozygosity, or may be in cis position, meaning that both mutations locate...

  8. Sexual selection, germline mutation rate and sperm competition

    Directory of Open Access Journals (Sweden)

    Møller AP

    2003-04-01

    Full Text Available Abstract Background An important component of sexual selection arises because females obtain viability benefits for their offspring from their mate choice. Females choosing extra-pair fertilization generally favor males with exaggerated secondary sexual characters, and extra-pair paternity increases the variance in male reproductive success. Furthermore, females are assumed to benefit from 'good genes' from extra-pair sires. How additive genetic variance in such viability genes is maintained despite strong directional selection remains an evolutionary enigma. We propose that sexual selection is associated with elevated mutation rates, changing the balance between mutation and selection, thereby increasing variance in fitness and hence the benefits to be obtained from good genes sexual selection. Two hypotheses may account for such elevated mutation: (1 Increased sperm production associated with sperm competition may increase mutation rate. (2 Mutator alleles increase mutation rates that are revealed by the expression of condition-dependent secondary sexual characters used by choosy females during their mate choice. M Petrie has independently developed the idea that mutator alleles may account for the maintenance of genetic variation in viability despite strong directional selection. Results A comparative study of birds revealed a positive correlation between mutation rate at minisatellite loci and extra-pair paternity, but not between mutation rate and relative testes mass which is a measure of relative sperm production. Minisatellite mutation rates were not related to longevity, suggesting a meiotic rather than a mitotic origin of mutations. Conclusion We found evidence of increased mutation rate in species with more intense sexual selection. Increased mutation was not associated with increased sperm production, and we suggest that species with intense sexual selection may maintain elevated mutation rates because sexual selection continuously

  9. Distinct pattern of p53 mutations in bladder cancer

    DEFF Research Database (Denmark)

    Spruck, C H; Rideout, W M; Olumi, A F

    1993-01-01

    A distinct mutational spectrum for the p53 tumor suppressor gene in bladder carcinomas was established in patients with known exposures to cigarette smoke. Single-strand conformational polymorphism analysis of exons 5 through 8 of the p53 gene showed inactivating mutations in 16 of 40 (40%) bladder...... tumors from smokers and 13 of 40 (33%) tumors from lifetime nonsmokers. Overall, 13 of the 50 (26%) total point mutations discovered in this and previous work were G:C-->C:G transversions, a relatively rare mutational type in human tumors. In six tumors, identical AGA (Arg)-->ACA (Thr) point mutations...... double mutations, four of which were tandem mutations on the same allele. No double mutations were found in tumors from nonsmoking patients. None of the mutations in smokers were G:C-->T:A transversions, which would be anticipated for exposure to the suspected cigarette smoke carcinogen 4-aminobiphenyl...

  10. Microangiopathic complications related to different alleles of ...

    African Journals Online (AJOL)

    Egyptian Journal of Biochemistry and Molecular Biology. Journal Home ... Microangiopathic complications related to different alleles of manganese superoxide dismutase gene in diabetes mellitus type 1. TM EL Masry ... 23(2) 2005: 155-167 ...

  11. Quantitative threefold allele-specific PCR (QuanTAS-PCR) for highly sensitive JAK2 V617F mutant allele detection

    International Nuclear Information System (INIS)

    Zapparoli, Giada V; Jorissen, Robert N; Hewitt, Chelsee A; McBean, Michelle; Westerman, David A; Dobrovic, Alexander

    2013-01-01

    The JAK2 V617F mutation is the most frequent somatic change in myeloproliferative neoplasms, making it an important tumour-specific marker for diagnostic purposes and for the detection of minimal residual disease. Sensitive quantitative assays are required for both applications, particularly for the monitoring of minimal residual disease, which requires not only high sensitivity but also very high specificity. We developed a highly sensitive probe-free quantitative mutant-allele detection method, Quantitative Threefold Allele-Specific PCR (QuanTAS-PCR), that is performed in a closed-tube system, thus eliminating the manipulation of PCR products. QuantTAS-PCR uses a threefold approach to ensure allele-specific amplification of the mutant sequence: (i) a mutant allele-specific primer, (ii) a 3′dideoxy blocker to suppress false-positive amplification from the wild-type template and (iii) a PCR specificity enhancer, also to suppress false-positive amplification from the wild-type template. Mutant alleles were quantified relative to exon 9 of JAK2. We showed that the addition of the 3′dideoxy blocker suppressed but did not eliminate false-positive amplification from the wild-type template. However, the addition of the PCR specificity enhancer near eliminated false-positive amplification from the wild-type allele. Further discrimination between true and false positives was enabled by using the quantification cycle (Cq) value of a single mutant template as a cut-off point, thus enabling robust distinction between true and false positives. As 10,000 JAK2 templates were used per replicate, the assay had a sensitivity of 1/10 -4 per replicate. Greater sensitivity could be reached by increasing the number of replicates analysed. Variation in replicates when low mutant-allele templates were present necessitated the use of a statistics-based approach to estimate the load of mutant JAK2 copies. QuanTAS-PCR showed comparable quantitative results when validated against a

  12. Murine muscular dystrophy caused by a mutation in the laminin alpha 2 (Lama2) gene

    DEFF Research Database (Denmark)

    Xu, H; Wu, X R; Wewer, U M

    1994-01-01

    The classic murine muscular dystrophy strain, dy, was first described almost 40 years ago. We have identified the molecular basis of an allele of dy, called dy2J, by detecting a mutation in the laminin alpha 2 chain gene--the first identified mutation in laminin-2. The G to A mutation in a splice...

  13. The directed mutation controversy and neo-Darwinism.

    Science.gov (United States)

    Lenski, R E; Mittler, J E

    1993-01-08

    According to neo-Darwinian theory, random mutation produces genetic differences among organisms whereas natural selection tends to increase the frequency of advantageous alleles. However, several recent papers claim that certain mutations in bacteria and yeast occur at much higher rates specifically when the mutant phenotypes are advantageous. Various molecular models have been proposed that might explain these directed mutations, but the models have not been confirmed. Critics contend that studies purporting to demonstrate directed mutation lack certain controls and fail to account adequately for population dynamics. Further experiments that address these criticisms do not support the existence of directed mutations.

  14. An allele of the crm gene blocks cyanobacterial circadian rhythms.

    Science.gov (United States)

    Boyd, Joseph S; Bordowitz, Juliana R; Bree, Anna C; Golden, Susan S

    2013-08-20

    The SasA-RpaA two-component system constitutes a key output pathway of the cyanobacterial Kai circadian oscillator. To date, rhythm of phycobilisome associated (rpaA) is the only gene other than kaiA, kaiB, and kaiC, which encode the oscillator itself, whose mutation causes completely arrhythmic gene expression. Here we report a unique transposon insertion allele in a small ORF located immediately upstream of rpaA in Synechococcus elongatus PCC 7942 termed crm (for circadian rhythmicity modulator), which results in arrhythmic promoter activity but does not affect steady-state levels of RpaA. The crm ORF complements the defect when expressed in trans, but only if it can be translated, suggesting that crm encodes a small protein. The crm1 insertion allele phenotypes are distinct from those of an rpaA null; crm1 mutants are able to grow in a light:dark cycle and have no detectable oscillations of KaiC phosphorylation, whereas low-amplitude KaiC phosphorylation rhythms persist in the absence of RpaA. Levels of phosphorylated RpaA in vivo measured over time are significantly altered compared with WT in the crm1 mutant as well as in the absence of KaiC. Taken together, these results are consistent with the hypothesis that the Crm polypeptide modulates a circadian-specific activity of RpaA.

  15. The loss-of-allele assay for ES cell screening and mouse genotyping.

    Science.gov (United States)

    Frendewey, David; Chernomorsky, Rostislav; Esau, Lakeisha; Om, Jinsop; Xue, Yingzi; Murphy, Andrew J; Yancopoulos, George D; Valenzuela, David M

    2010-01-01

    Targeting vectors used to create directed mutations in mouse embryonic stem (ES) cells consist, in their simplest form, of a gene for drug selection flanked by mouse genomic sequences, the so-called homology arms that promote site-directed homologous recombination between the vector and the target gene. The VelociGene method for the creation of targeted mutations in ES cells employs targeting vectors, called BACVecs, that are based on bacterial artificial chromosomes. Compared with conventional short targeting vectors, BacVecs provide two major advantages: (1) their much larger homology arms promote high targeting efficiencies without the need for isogenicity or negative selection strategies; and (2) they enable deletions and insertions of up to 100kb in a single targeting event, making possible gene-ablating definitive null alleles and other large-scale genomic modifications. Because of their large arm sizes, however, BACVecs do not permit screening by conventional assays, such as long-range PCR or Southern blotting, that link the inserted targeting vector to the targeted locus. To exploit the advantages of BACVecs for gene targeting, we inverted the conventional screening logic in developing the loss-of-allele (LOA) assay, which quantifies the number of copies of the native locus to which the mutation was directed. In a correctly targeted ES cell clone, the LOA assay detects one of the two native alleles (for genes not on the X or Y chromosome), the other allele being disrupted by the targeted modification. We apply the same principle in reverse as a gain-of-allele assay to quantify the copy number of the inserted targeting vector. The LOA assay reveals a correctly targeted clone as having lost one copy of the native target gene and gained one copy of the drug resistance gene or other inserted marker. The combination of these quantitative assays makes LOA genotyping unequivocal and amenable to automated scoring. We use the quantitative polymerase chain reaction

  16. Microsatellite D21D210 (GT-12) allele frequencies in sporadic Alzheimer's disease

    International Nuclear Information System (INIS)

    Lannfelt, L.; Lilius, L.; Viitanen, M.; Winblad, B.; Basun, H.; Houlden, H.; Rossor, M.; Hardy, J.

    1995-01-01

    Four disease-causing mutations have so far been described in the amyloid precursor protein gene on chromosome 21 in familial early-onset Alzheimer's disease. Linkage analysis with a fourteen-allele microsatellite at D21S210 named GT-12 has proven useful in the elucidation of amyloid presursor protein gene involvement in Alzheimer's disease families, as it is closely linked to the gene. Most cases of Alzheimer's disease are thought to be sporadic and not familial. However, evidence from earlier studies suggests an important genetic contribution also in sporadic cases, where gene-environment interaction may contribute to the disease. We have determined frequencies of the GT-12 alleles in 78 Swedish and 49 British sporadic Alzheimer's disease cases and 104 healthy elderly control subjects, to investigate if the disease associates with a particular genotype in GT-12. However, no differences in allele frequencies were observed between any of the groups. (au) (26 refs.)

  17. Genetic analysis of gamma-ray mutagenesis in yeast. II. Allele-specific control of mutagenesis

    International Nuclear Information System (INIS)

    McKee, R.H.; Lawrence, C.W.

    1979-01-01

    We find that partially different sets of gene functions are required for the production of different kinds of mutations induced by 60 Co γ rays in Saccharomyces cerevisiae. This observation is very similar to others made previously with respect to uv mutagenesis and confirms the conclusion that such distinctive patterns of genetic control reflect properties of the test alleles and their genetic locations, rather than the kinds of lesions required to revert them. The data also support the model of mutagenic repair outlined in the first paper of this series in which partially different sets of gene functions are required for the production of different kinds of mutations, the formation of mutations at different genetic sites and the induction of mutations by different mutagens

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

    Directory of Open Access Journals (Sweden)

    Carol A Soderlund

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

  19. Abnormal segregation of alleles in CEPH pedigree DNAs arising from allele loss in lymphoblastoid DNA.

    Science.gov (United States)

    Royle, N J; Armour, J A; Crosier, M; Jeffreys, A J

    1993-01-01

    Somatic events that result in the reduction to hemi- or homozygosity at all loci affected by the event have been identified in lymphoblastoid DNA from mothers of two CEPH families. Using suitably informative probes, the allele deficiencies were detected by the abnormal transmission of alleles from grandparents to grandchildren, with the apparent absence of the alleles from the parent. Undetected somatic deficiencies in family DNAs could result in misscoring of recombination events and consequently introduce errors into linkage analysis.

  20. Always look on both sides: phylogenetic information conveyed by simple sequence repeat allele sequences.

    Directory of Open Access Journals (Sweden)

    Stéphanie Barthe

    Full Text Available Simple sequence repeat (SSR markers are widely used tools for inferences about genetic diversity, phylogeography and spatial genetic structure. Their applications assume that variation among alleles is essentially caused by an expansion or contraction of the number of repeats and that, accessorily, mutations in the target sequences follow the stepwise mutation model (SMM. Generally speaking, PCR amplicon sizes are used as direct indicators of the number of SSR repeats composing an allele with the data analysis either ignoring the extent of allele size differences or assuming that there is a direct correlation between differences in amplicon size and evolutionary distance. However, without precisely knowing the kind and distribution of polymorphism within an allele (SSR and the associated flanking region (FR sequences, it is hard to say what kind of evolutionary message is conveyed by such a synthetic descriptor of polymorphism as DNA amplicon size. In this study, we sequenced several SSR alleles in multiple populations of three divergent tree genera and disentangled the types of polymorphisms contained in each portion of the DNA amplicon containing an SSR. The patterns of diversity provided by amplicon size variation, SSR variation itself, insertions/deletions (indels, and single nucleotide polymorphisms (SNPs observed in the FRs were compared. Amplicon size variation largely reflected SSR repeat number. The amount of variation was as large in FRs as in the SSR itself. The former contributed significantly to the phylogenetic information and sometimes was the main source of differentiation among individuals and populations contained by FR and SSR regions of SSR markers. The presence of mutations occurring at different rates within a marker's sequence offers the opportunity to analyse evolutionary events occurring on various timescales, but at the same time calls for caution in the interpretation of SSR marker data when the distribution of within

  1. Attenuated Expression of DFFB is a Hallmark of Oligodendrogliomas with 1p-Allelic Loss

    Directory of Open Access Journals (Sweden)

    Fuller Gregory N

    2005-09-01

    Full Text Available Abstract Allelic loss of chromosome 1p is frequently observed in oligodendroglioma. We screened 177 oligodendroglial tumors for 1p deletions and found 6 tumors with localized 1p36 deletions. Several apoptosis regulation genes have been mapped to this region, including Tumor Protein 73 (p73, DNA Fragmentation Factor subunits alpha (DFFA and beta (DFFB, and Tumor Necrosis Factor Receptor Superfamily Members 9 and 25 (TNFRSF9, TNFRSF25. We compared expression levels of these 5 genes in pairs of 1p-loss and 1p-intact tumors using quantitative reverse-transcriptase PCR (QRTPCR to test if 1p deletions had an effect on expression. Only the DFFB gene demonstrated decreased expression in all tumor pairs tested. Mutational analysis did not reveal DFFB mutations in 12 tested samples. However, it is possible that DFFB haploinsufficiency from 1p allelic loss is a contributing factor in oligodendroglioma development.

  2. Presentation of Complex Homozygous Allele in ABCA4 Gene in a Patient with Retinitis Pigmentosa

    Directory of Open Access Journals (Sweden)

    Māreta Audere

    2015-01-01

    Full Text Available Retinitis pigmentosa is a degenerative retinal disease characterized by progressive photoreceptor damage, which causes loss of peripheral and night vision and the development of tunnel vision and may result in loss of central vision. This study describes a patient with retinitis pigmentosa caused by a mutation in the ABCA4 gene with complex allele c.1622T>C, p.L541P; c.3113C>T, p.A1038V in homozygous state.

  3. The late flowering phenotype of fwa mutants is caused by gain-of-function epigenetic alleles of a homeodomain gene

    NARCIS (Netherlands)

    Soppe, W.J.J.; Jacobsen, S.E.; Alonso-Blanco, C.; Jackson, J.P.; Kakutani, T.; Koornneef, M.; Peeters, A.J.M.

    2000-01-01

    The transition to flowering in Arabidopsis thaliana is delayed in fwa mutant plants. FWA was identified by loss-of-function mutations in normally flowering revertants of the fwa mutant, and it encodes a homeodomain-containing transcription factor. The DNA sequence of wild-type and fwa mutant alleles

  4. Allele-Specific DNA Methylation and Its Interplay with Repressive Histone Marks at Promoter-Mutant TERT Genes

    Directory of Open Access Journals (Sweden)

    Josh Lewis Stern

    2017-12-01

    Full Text Available A mutation in the promoter of the Telomerase Reverse Transcriptase (TERT gene is the most frequent noncoding mutation in cancer. The mutation drives unusual monoallelic expression of TERT, allowing immortalization. Here, we find that DNA methylation of the TERT CpG island (CGI is also allele-specific in multiple cancers. The expressed allele is hypomethylated, which is opposite to cancers without TERT promoter mutations. The continued presence of Polycomb repressive complex 2 (PRC2 on the inactive allele suggests that histone marks of repressed chromatin may be causally linked to high DNA methylation. Consistent with this hypothesis, TERT promoter DNA containing 5-methyl-CpG has much increased affinity for PRC2 in vitro. Thus, CpG methylation and histone marks appear to collaborate to maintain the two TERT alleles in different epigenetic states in TERT promoter mutant cancers. Finally, in several cancers, DNA methylation levels at the TERT CGI correlate with altered patient survival.

  5. Allele-Specific DNA Methylation and Its Interplay with Repressive Histone Marks at Promoter-Mutant TERT Genes.

    Science.gov (United States)

    Stern, Josh Lewis; Paucek, Richard D; Huang, Franklin W; Ghandi, Mahmoud; Nwumeh, Ronald; Costello, James C; Cech, Thomas R

    2017-12-26

    A mutation in the promoter of the Telomerase Reverse Transcriptase (TERT) gene is the most frequent noncoding mutation in cancer. The mutation drives unusual monoallelic expression of TERT, allowing immortalization. Here, we find that DNA methylation of the TERT CpG island (CGI) is also allele-specific in multiple cancers. The expressed allele is hypomethylated, which is opposite to cancers without TERT promoter mutations. The continued presence of Polycomb repressive complex 2 (PRC2) on the inactive allele suggests that histone marks of repressed chromatin may be causally linked to high DNA methylation. Consistent with this hypothesis, TERT promoter DNA containing 5-methyl-CpG has much increased affinity for PRC2 in vitro. Thus, CpG methylation and histone marks appear to collaborate to maintain the two TERT alleles in different epigenetic states in TERT promoter mutant cancers. Finally, in several cancers, DNA methylation levels at the TERT CGI correlate with altered patient survival. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  6. Oncogene mutational profile in nasopharyngeal carcinoma

    Directory of Open Access Journals (Sweden)

    Zhang ZC

    2014-03-01

    Full Text Available Zi-Chen Zhang,1,* Sha Fu,1,* Fang Wang,1 Hai-Yun Wang,1 Yi-Xin Zeng,2 Jian-Yong Shao11Department of Molecular Diagnostics, 2Department of Experimental Research, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou, People's Republic of China *These authors contributed equally to this work Abstract: Nasopharyngeal carcinoma (NPC is a common tumor in Southern China, but the oncogene mutational status of NPC patients has not been clarified. Using time-of-flight mass spectrometry, 238 mutation hotspots in 19 oncogenes were examined in 123 NPC patients. The relationships between mutational status and clinical data were assessed with a χ2 or Fisher's exact test. Survival analysis was performed using the Kaplan–Meier method with the log-rank test. In 123 patients, 21 (17.1% NPC tumors were positive for mutations in eight oncogenes: six patients had PIK3CA mutations (4.9%, five NRAS mutations (4.1%, four KIT mutations (3.3%, two PDGFRA mutations (1.6%, two ABL mutations (1.6%, and one with simultaneous mutations in HRAS, EGFR, and BRAF (1%. Patients with mutations were more likely to relapse or develop metastasis than those with wild-type alleles (P=0.019. No differences or correlations were found in other clinical characteristics or in patient survival. No mutations were detected in oncogenes AKT1, AKT2, CDK, ERBB2, FGFR1, FGFR3, FLT3, JAK2, KRAS, MET, and RET. These results demonstrate an association between NPC and mutations in NRAS, KIT, PIK3CA, PDGFRA, and ABL, which are associated with patient relapse and metastasis. Keywords: NPC, oncogene, mutation

  7. Fitness effects of beneficial mutations: the mutational landscape model in experimental evolution

    DEFF Research Database (Denmark)

    Betancourt, Andrea J.; Bollback, Jonathan Paul

    2006-01-01

    of beneficial mutations should be roughly exponentially distributed. The prediction appears to be borne out by most of these studies, at least qualitatively. Another study showed that a modified version of the model was able to predict, with reasonable accuracy, which of a ranked set of beneficial alleles...

  8. Mutation at the Human D1S80 Minisatellite Locus

    Directory of Open Access Journals (Sweden)

    Kuppareddi Balamurugan

    2012-01-01

    Full Text Available Little is known about the general biology of minisatellites. The purpose of this study is to examine repeat mutations from the D1S80 minisatellite locus by sequence analysis to elucidate the mutational process at this locus. This is a highly polymorphic minisatellite locus, located in the subtelomeric region of chromosome 1. We have analyzed 90,000 human germline transmission events and found seven (7 mutations at this locus. The D1S80 alleles of the parentage trio, the child, mother, and the alleged father were sequenced and the origin of the mutation was determined. Using American Association of Blood Banks (AABB guidelines, we found a male mutation rate of 1.04×10-4 and a female mutation rate of 5.18×10-5 with an overall mutation rate of approximately 7.77×10-5. Also, in this study, we found that the identified mutations are in close proximity to the center of the repeat array rather than at the ends of the repeat array. Several studies have examined the mutational mechanisms of the minisatellites according to infinite allele model (IAM and the one-step stepwise mutation model (SMM. In this study, we found that this locus fits into the one-step mutation model (SMM mechanism in six out of seven instances similar to STR loci.

  9. High mutation rates limit evolutionary adaptation in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Kathleen Sprouffske

    2018-04-01

    Full Text Available Mutation is fundamental to evolution, because it generates the genetic variation on which selection can act. In nature, genetic changes often increase the mutation rate in systems that range from viruses and bacteria to human tumors. Such an increase promotes the accumulation of frequent deleterious or neutral alleles, but it can also increase the chances that a population acquires rare beneficial alleles. Here, we study how up to 100-fold increases in Escherichia coli's genomic mutation rate affect adaptive evolution. To do so, we evolved multiple replicate populations of asexual E. coli strains engineered to have four different mutation rates for 3000 generations in the laboratory. We measured the ability of evolved populations to grow in their original environment and in more than 90 novel chemical environments. In addition, we subjected the populations to whole genome population sequencing. Although populations with higher mutation rates accumulated greater genetic diversity, this diversity conveyed benefits only for modestly increased mutation rates, where populations adapted faster and also thrived better than their ancestors in some novel environments. In contrast, some populations at the highest mutation rates showed reduced adaptation during evolution, and failed to thrive in all of the 90 alternative environments. In addition, they experienced a dramatic decrease in mutation rate. Our work demonstrates that the mutation rate changes the global balance between deleterious and beneficial mutational effects on fitness. In contrast to most theoretical models, our experiments suggest that this tipping point already occurs at the modest mutation rates that are found in the wild.

  10. Hypomorphic temperature-sensitive alleles of NSDHL cause CK syndrome.

    Science.gov (United States)

    McLarren, Keith W; Severson, Tesa M; du Souich, Christèle; Stockton, David W; Kratz, Lisa E; Cunningham, David; Hendson, Glenda; Morin, Ryan D; Wu, Diane; Paul, Jessica E; An, Jianghong; Nelson, Tanya N; Chou, Athena; DeBarber, Andrea E; Merkens, Louise S; Michaud, Jacques L; Waters, Paula J; Yin, Jingyi; McGillivray, Barbara; Demos, Michelle; Rouleau, Guy A; Grzeschik, Karl-Heinz; Smith, Raffaella; Tarpey, Patrick S; Shears, Debbie; Schwartz, Charles E; Gecz, Jozef; Stratton, Michael R; Arbour, Laura; Hurlburt, Jane; Van Allen, Margot I; Herman, Gail E; Zhao, Yongjun; Moore, Richard; Kelley, Richard I; Jones, Steven J M; Steiner, Robert D; Raymond, F Lucy; Marra, Marco A; Boerkoel, Cornelius F

    2010-12-10

    CK syndrome (CKS) is an X-linked recessive intellectual disability syndrome characterized by dysmorphism, cortical brain malformations, and an asthenic build. Through an X chromosome single-nucleotide variant scan in the first reported family, we identified linkage to a 5 Mb region on Xq28. Sequencing of this region detected a segregating 3 bp deletion (c.696_698del [p.Lys232del]) in exon 7 of NAD(P) dependent steroid dehydrogenase-like (NSDHL), a gene that encodes an enzyme in the cholesterol biosynthesis pathway. We also found that males with intellectual disability in another reported family with an NSDHL mutation (c.1098 dup [p.Arg367SerfsX33]) have CKS. These two mutations, which alter protein folding, show temperature-sensitive protein stability and complementation in Erg26-deficient yeast. As described for the allelic disorder CHILD syndrome, cells and cerebrospinal fluid from CKS patients have increased methyl sterol levels. We hypothesize that methyl sterol accumulation, not only cholesterol deficiency, causes CKS, given that cerebrospinal fluid cholesterol, plasma cholesterol, and plasma 24S-hydroxycholesterol levels are normal in males with CKS. In summary, CKS expands the spectrum of cholesterol-related disorders and insight into the role of cholesterol in human development. Copyright © 2010 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  11. Diversity of [beta]-globin mutations in Israeli ethnic groups reflects recent historic events

    Energy Technology Data Exchange (ETDEWEB)

    Filon, D.; Oron, V.; Krichevski, S.; Shaag, A.; Goldfarb, A.; Aker, M.; Rachmilewitz, E.A.; Rund, D.; Oppenheim, A. (Hebrew Univ. Hadassah-Medical School, Jerusalem (Israel)) (and others)

    1994-05-01

    The authors characterized nearly 500 [beta]-thalassemia genes from the Israeli population representing a variety of ethnic subgroups. They found 28 different mutations in the [beta]-globin gene, including three mutations ([beta][sup S], [beta][sup C], and [beta][sup O-Arab]) causing hemoglobinopathies. Marked genetic heterogeneity was observed in both the Arab (20 mutations) and Jewish (17 mutations) populations. On the other hand, two ethnic isolates - Druze and Samaritans - had a single mutation each. Fifteen of the [beta]-thalassemia alleles are Mediterranean in type, 5 originated in Kurdistan, 2 are of Indian origin, and 2 sporadic alleles came from Europe. Only one mutant allele-nonsense codon 37-appears to be indigenous to Israel. While human habitation in Israel dates back to early prehistory, the present-day spectrum of [beta]-globin mutations can be largely explained by migration events that occurred in the past millennium. 26 refs., 2 figs., 3 tabs.

  12. Estimated allele substitution effects underlying genomic evaluation models depend on the scaling of allele counts

    NARCIS (Netherlands)

    Bouwman, Aniek C.; Hayes, Ben J.; Calus, Mario P.L.

    2017-01-01

    Background: Genomic evaluation is used to predict direct genomic values (DGV) for selection candidates in breeding programs, but also to estimate allele substitution effects (ASE) of single nucleotide polymorphisms (SNPs). Scaling of allele counts influences the estimated ASE, because scaling of

  13. Eighty percent of French sport winners in Olympic, World and Europeans competitions have mutations in the hemochromatosis HFE gene.

    Science.gov (United States)

    Hermine, Olivier; Dine, Gérard; Genty, Vincent; Marquet, Laurie-Anne; Fumagalli, Gabriela; Tafflet, Muriel; Guillem, Flavia; Van Lierde, Françoise; Rousseaux-Blanchi, Marie-Philippe; Palierne, Christian; Lapostolle, Jean-Claude; Cervetti, Jean-Pierre; Frey, Alain; Jouven, Xavier; Noirez, Philippe; Toussaint, Jean-François

    2015-12-01

    The HFE gene encodes a protein involved in iron homeostasis; individuals with mutations in both alleles develop hemochromatosis. 27% of the French population is heterozygous for mutations in this gene. We found that 80% of the French athletes who won international competitions in rowing, Nordic skiing and judo display mutations in one allele of HFE, thus demonstrating the existence of a favourable phenotype linked to this heterozygosity. Copyright © 2015. Published by Elsevier B.V.

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

    Directory of Open Access Journals (Sweden)

    Jesus Perez-Losada

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

  15. Genotype-phenotype correlation and functional studies in patients with cystic fibrosis bearing CFTR complex alleles.

    Science.gov (United States)

    Terlizzi, Vito; Castaldo, Giuseppe; Salvatore, Donatello; Lucarelli, Marco; Raia, Valeria; Angioni, Adriano; Carnovale, Vincenzo; Cirilli, Natalia; Casciaro, Rosaria; Colombo, Carla; Di Lullo, Antonella Miriam; Elce, Ausilia; Iacotucci, Paola; Comegna, Marika; Scorza, Manuela; Lucidi, Vincenzina; Perfetti, Anna; Cimino, Roberta; Quattrucci, Serena; Seia, Manuela; Sofia, Valentina Maria; Zarrilli, Federica; Amato, Felice

    2017-04-01

    The effect of complex alleles in cystic fibrosis (CF) is poorly defined for the lack of functional studies. To describe the genotype-phenotype correlation and the results of either in vitro and ex vivo studies performed on nasal epithelial cells (NEC) in a cohort of patients with CF carrying cystic fibrosis transmembrane conductance regulator ( CFTR ) complex alleles. We studied 70 homozygous, compound heterozygous or heterozygous for CFTR mutations: p.[Arg74Trp;Val201Met;Asp1270Asn], n=8; p.[Ile148Thr;Ile1023_Val1024del], n=5; p.[Arg117Leu;Leu997Phe], n=6; c.[1210-34TG[12];1210-12T[5];2930C>T], n=3; p.[Arg74Trp;Asp1270Asn], n=4; p.Asp1270Asn, n=2; p.Ile148Thr, n=6; p.Leu997Phe, n=36. In 39 patients, we analysed the CFTR gating activity on NEC in comparison with patients with CF (n=8) and carriers (n=4). Finally, we analysed in vitro the p.[Arg74Trp;Val201Met;Asp1270Asn] complex allele. The p.[Ile148Thr;Ile1023_Val1024del] caused severe CF in five compound heterozygous with a class I-II mutation. Their CFTR activity on NEC was comparable with patients with two class I-II mutations (mean 7.3% vs 6.9%). The p.[Arg74Trp;Asp1270Asn] and the p.Asp1270Asn have scarce functional effects, while p.[Arg74Trp;Val201Met;Asp1270Asn] caused mild CF in four of five subjects carrying a class I-II mutation in trans , or CFTR-related disorders (CFTR-RD) in three having in trans a class IV-V mutation. The p.[Arg74Trp;Val201Met;Asp1270Asn] causes significantly (pT] and a class I-II mutation had mild CF or CFTR-RD (gating activity: 18.5-19.0%). The effect of complex alleles partially depends on the mutation in trans . Although larger studies are necessary, the CFTR activity on NEC is a rapid contributory tool to classify patients with CFTR dysfunction. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. Diminished levels of allelic losses by homologous recombination in radiation-hypersensitive cells

    International Nuclear Information System (INIS)

    Tatsumi, K.; Abe, M.; Hoki, Y.; Kubo, E.; Muto, M.; Araki, R.; Sato, K.

    2003-01-01

    Mitotic recombination (MR) due to somatic crossing-over is a predominant mechanism for allelic losses in mammalian cells either spontaneous or radiation-induced. A selectable mutation assay accompanying real-time detection PCR was developed to analyze the second step in loss-of-function mutations employing a human lympho-blastoid cell line derived from an obligate heterozygote of 2,8-dihydroxyadenine urolithiasis, adenine phosphoribosyltransferase (APRT) deficiency with a nonsense mutation at exon 3 of the gene. 68 % of spontaneously arising 2,6-diaminopurine resistance (DAP r ) mutant clones were associated with loss of heterozygosity (LOH), while 92 % of 2 Gy gamma-ray induced mutant clones were so associated. Investigation of gene dosage revealed that about one half of the spontaneously arising mutant clones and two-thirds of those induced by gamma-rays showed reduction to homozygosity of the constitutionally inactivated APRT allele. In an ataxia telangiectasia (AT) cell subline in which a new inactivation mutation had been introduced into one APRT allele by ICR-191, MR rarely occurred and exclusively deletions predominated in both spontaneous and X-ray induced DAP r mutants with LOH. A similar assay system was also developed with C3H mouse FM3A mammary tumor cells, SR-1, carrying a C .T transition at exon 5 of an APRT allele. In an XRCC7 (DNA-PKcs) deficient subline of SR-1, SX9 , spontaneous mutation frequencies for the Aprt locus (8AA r ) was 10 -3 , which was about 10 times higher than that in parental SR-1 cells. Mutation frequencies induced by X-rays comparably increased in a dose-dependent manner for the Aprt locus in both cell lines. Against our expectation, the lack of an NHEJ pathway of DNA double strand break repair resulted in a lower proportion (11.1 %) of MR with deletions (77.8 %) as the molecular cause for 8AA r mutations following X-irradiation, while virtually all of X-ray induced 8AA r mutant clones were MR in the control SR-1 cells. Factors

  17. A Reverse-Genetics Mutational Analysis of the Barley HvDWARF Gene Results in Identification of a Series of Alleles and Mutants with Short Stature of Various Degree and Disturbance in BR Biosynthesis Allowing a New Insight into the Process.

    Science.gov (United States)

    Gruszka, Damian; Gorniak, Malgorzata; Glodowska, Ewelina; Wierus, Ewa; Oklestkova, Jana; Janeczko, Anna; Maluszynski, Miroslaw; Szarejko, Iwona

    2016-04-22

    Brassinosteroids (BRs) are plant steroid hormones, regulating a broad range of physiological processes. The largest amount of data related with BR biosynthesis has been gathered in Arabidopsis thaliana, however understanding of this process is far less elucidated in monocot crops. Up to now, only four barley genes implicated in BR biosynthesis have been identified. Two of them, HvDWARF and HvBRD, encode BR-6-oxidases catalyzing biosynthesis of castasterone, but their relation is not yet understood. In the present study, the identification of the HvDWARF genomic sequence, its mutational and functional analysis and characterization of new mutants are reported. Various types of mutations located in different positions within functional domains were identified and characterized. Analysis of their impact on phenotype of the mutants was performed. The identified homozygous mutants show reduced height of various degree and disrupted skotomorphogenesis. Mutational analysis of the HvDWARF gene with the "reverse genetics" approach allowed for its detailed functional analysis at the level of protein functional domains. The HvDWARF gene function and mutants' phenotypes were also validated by measurement of endogenous BR concentration. These results allowed a new insight into the BR biosynthesis in barley.

  18. Allelic genealogies in sporophytic self-incompatibility systems in plants

    DEFF Research Database (Denmark)

    Schierup, Mikkel Heide; Vekemans, Xavier; Christiansen, Freddy Bugge

    1998-01-01

    , alleles act codominantly in both pollen and style, in the SSIdom model, alleles form a dominance hierarchy, and in SSIdomcod, alleles are codominant in the style and show a dominance hierarchy in the pollen. Coalescence times of alleles rarely differ more than threefold from those under gametophytic self...

  19. Allele-specific Gene Silencing of Mutant mRNA Restores Cellular Function in Ullrich Congenital Muscular Dystrophy Fibroblasts

    Directory of Open Access Journals (Sweden)

    Satoru Noguchi

    2014-01-01

    Full Text Available Ullrich congenital muscular dystrophy (UCMD is an inherited muscle disorder characterized clinically by muscle weakness, distal joint hyperlaxity, and proximal joint contractures. Sporadic and recessive mutations in the three collagen VI genes, COL6A1, COL6A2, and COL6A3, are reported to be causative. In the sporadic forms, a heterozygous point mutation causing glycine substitution in the triple helical domain has been identified in higher rate. In this study, we examined the efficacy of siRNAs, which target point mutation site, on specific knockdown toward transcripts from mutant allele and evaluated consequent cellular phenotype of UCMD fibroblasts. We evaluated the effect of siRNAs targeted to silence-specific COL6A1 alleles in UCMD fibroblasts, where simultaneous expression of both wild-type and mutant collagen VI resulted in defective collagen localization. Addition of mutant-specific siRNAs allowed normal extracellular localization of collagen VI surrounding fibroblasts, suggesting selective inhibition of mutant collagen VI. Targeting the single-nucleotide COL6A1 c.850G>A (p.G284R mutation responsible a sporadic autosomal dominant form of UCMD can potently and selectively block expression of mutant collagen VI. These results suggest that allele-specific knockdown of the mutant mRNA can potentially be considered as a therapeutic procedure in UCMD due to COL6A1 point mutations.

  20. RHD alleles in the Tunisian population

    Science.gov (United States)

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

    2013-01-01

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

  1. Diversity of Lactase Persistence Alleles in Ethiopia

    DEFF Research Database (Denmark)

    Jones, BL; Raga, TO; Liebert, Anke

    2013-01-01

    The persistent expression of lactase into adulthood in humans is a recent genetic adaptation that allows the consumption of milk from other mammals after weaning. In Europe, a single allele (−13910∗T, rs4988235) in an upstream region that acts as an enhancer to the expression of the lactase gene ...

  2. Origin, functional role, and clinical impact of Fanconi anemia FANCA mutations

    OpenAIRE

    Castella, Maria; Pujol, Roser; Callén, Elsa; Trujillo, Juan P.; Casado, José A.; Gille, Hans; Lach, Francis P.; Auerbach, Arleen D.; Schindler, Detlev; Benítez, Javier; Porto, Beatriz; Ferro, Teresa; Muñoz, Arturo; Sevilla, Julián; Madero, Luis

    2011-01-01

    Fanconi anemia is characterized by congenital abnormalities, bone marrow failure, and cancer predisposition. To investigate the origin, functional role, and clinical impact of FANCA mutations, we determined a FANCA mutational spectrum with 130 pathogenic alleles. Some of these mutations were further characterized for their distribution in populations, mode of emergence, or functional consequences at cellular and clinical level. The world most frequent FANCA mutation is not the result of a mut...

  3. Large deviations for the Fleming-Viot process with neutral mutation and selection

    OpenAIRE

    Dawson, Donald; Feng, Shui

    1998-01-01

    Large deviation principles are established for the Fleming-Viot processes with neutral mutation and selection, and the corresponding equilibrium measures as the sampling rate goes to 0. All results are first proved for the finite allele model, and then generalized, through the projective limit technique, to the infinite allele model. Explicit expressions are obtained for the rate functions.

  4. Estimating the probability of allelic drop-out of STR alleles in forensic genetics

    DEFF Research Database (Denmark)

    Tvedebrink, Torben; Eriksen, Poul Svante; Mogensen, Helle Smidt

    2009-01-01

    In crime cases with available DNA evidence, the amount of DNA is often sparse due to the setting of the crime. In such cases, allelic drop-out of one or more true alleles in STR typing is possible. We present a statistical model for estimating the per locus and overall probability of allelic drop......-out using the results of all STR loci in the case sample as reference. The methodology of logistic regression is appropriate for this analysis, and we demonstrate how to incorporate this in a forensic genetic framework....

  5. Mutation Spectrum of β-Thalassemia and Other Hemoglobinopathies in Chittagong, Southeast Bangladesh.

    Science.gov (United States)

    Chatterjee, Tridip; Chakravarty, Amit; Chakravarty, Sudipa; Chowdhury, Mahmood Ahmed; Sultana, Razia

    2015-01-01

    Thalassemia is one of the most common autosomal recessive blood disorders in the world. It shows a variety of clinical expression, starting from asymptomatic to severe blood transfusion dependence. More than 500 alleles have been characterized in or around the β-globin region. Moreover, most geographical regions have their own characteristics, frequency and availability of these alleles, predominantly circulating within the communities present in that particular region. In this study, we explored the spectrum of β-thalassemia (β-thal) alleles present in Chittagong, Southeast Bangladesh. This study comprises β-thal and Hb E (HBB: c.79 G > A) patients from in and around the area of Chittagong. Not only exploring the complete β-globin mutation spectrum of the area, but we also tried to look at the origin of the mutated alleles. The β-thal mutations of Bangladesh show a relatively wide spectrum of alleles, which further demonstrates the heterogeneity of the disease in this country. Although our study showed that the majority of the mutations have their origin in neighboring countries such as India, countries of Southeast Asia, Pakistan, etc., some unusual alleles do not originate in neighboring countries and put a little more diversity in the overall spectrum of β-thal-specific alleles. Overall, this study demonstrates the mutation spectrum related to β-thal in Chittagong, Southeast Bangladesh.

  6. Gene mutations in hepatocellular adenomas

    DEFF Research Database (Denmark)

    Raft, Marie B; Jørgensen, Ernö N; Vainer, Ben

    2015-01-01

    is associated with bi-allelic mutations in the TCF1 gene and morphologically has marked steatosis. β-catenin activating HCA has increased activity of the Wnt/β-catenin pathway and is associated with possible malignant transformation. Inflammatory HCA is characterized by an oncogene-induced inflammation due...... to alterations in the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. In the diagnostic setting, sub classification of HCA is based primarily on immunohistochemical analyzes, and has had an increasing impact on choice of treatment and individual prognostic assessment....... This review offers an overview of the reported gene mutations associated with hepatocellular adenomas together with a discussion of the diagnostic and prognostic value....

  7. Estimating spontaneous mutation rates at enzyme loci in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Mukai, Terumi; Yamazaki, Tsuneyuki; Harada, Ko; Kusakabe, Shin-ichi

    1990-04-01

    Spontaneous mutations were accumulated for 1,620,826 allele-generations on chromosomes that originated from six stem second chromosomes of Drosophila melanogaster. Only null-electromorph mutations were detected. Band-electromorph mutations were not found. The average rate of null-electromorph mutations was 2.71 x 10 -5 per locus per generation. The 95% confidence interval (μ n ) was 1.97 x 10 -5 n -5 per locus per generation. The upper 95% confidence limit of the band-electromorph mutation rate (μ B ) was 2.28 x 10 -6 per locus per generation. It appeared that null mutations were induced by movable genetic elements and that the mutation rates were different from chromosome to chromosome. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-02-01

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

  9. Linkage disequilibrium in the insulin gene region: Size variation at the 5{prime} flanking polymorphism and bimodality among {open_quotes}Class I{close_quotes} alleles

    Energy Technology Data Exchange (ETDEWEB)

    McGinnis, R.E.; Spielman, R.S. [Univ. of Pennsylvania School of Medicine, Philadelphia, PA (United States)

    1994-09-01

    The 5{prime} flanking polymorphism (5{prime}FP), a hypervariable region at the 5{prime} end of the insulin gene, has {open_quotes}class 1{close_quotes} alleles (650-900 bp long) that are in positive linkage disequilibrium with insulin-dependent diabetes mellitus (IDDM). The authors report that precise sizing of the 5{prime}FP yields a bimodal frequency distribution of class 1 allele lengths. Class 1 alleles belonging to the lower component (650-750 bp) of the bimodal distribution were somewhat more highly associated with IDDM than were alleles from the upper component (760-900 bp), but the difference was not statistically significant. They also examined 5{prime}FP length variation in relation to allelic variation at nearby polymorphisms. At biallelic RFLPs on both sides of the 5{prime}FP, they found that one allele exhibits near-total association with the upper component of the 5FP class 1 distribution. Such associations represent a little-known but potentially wide-spread form of linkage disequilibrium. In this type of disequilibrium, a flanking allele has near-complete association with a single mode of VNTR alleles whose lengths represent consecutive numbers of tandem repeats (CNTR). Such extreme disequilibrium between a CNTR mode and flanking alleles may originate and persist because length mutations at some VNTR loci usually add or delete only one or two repeat units. 22 refs., 5 figs., 6 tabs.

  10. Genome-wide survey of allele-specific splicing in humans

    Directory of Open Access Journals (Sweden)

    Scheffler Konrad

    2008-06-01

    Full Text Available Abstract Background Accurate mRNA splicing depends on multiple regulatory signals encoded in the transcribed RNA sequence. Many examples of mutations within human splice regulatory regions that alter splicing qualitatively or quantitatively have been reported and allelic differences in mRNA splicing are likely to be a common and important source of phenotypic diversity at the molecular level, in addition to their contribution to genetic disease susceptibility. However, because the effect of a mutation on the efficiency of mRNA splicing is often difficult to predict, many mutations that cause disease through an effect on splicing are likely to remain undiscovered. Results We have combined a genome-wide scan for sequence polymorphisms likely to affect mRNA splicing with analysis of publicly available Expressed Sequence Tag (EST and exon array data. The genome-wide scan uses published tools and identified 30,977 SNPs located within donor and acceptor splice sites, branch points and exonic splicing enhancer elements. For 1,185 candidate splicing polymorphisms the difference in splicing between alternative alleles was corroborated by publicly available exon array data from 166 lymphoblastoid cell lines. We developed a novel probabilistic method to infer allele-specific splicing from EST data. The method uses SNPs and alternative mRNA isoforms mapped to EST sequences and models both regulated alternative splicing as well as allele-specific splicing. We have also estimated heritability of splicing and report that a greater proportion of genes show evidence of splicing heritability than show heritability of overall gene expression level. Our results provide an extensive resource that can be used to assess the possible effect on splicing of human polymorphisms in putative splice-regulatory sites. Conclusion We report a set of genes showing evidence of allele-specific splicing from an integrated analysis of genomic polymorphisms, EST data and exon array

  11. Characterization of new allele influencing flowering time in bread wheat introgressed from Triticum militinae.

    Science.gov (United States)

    Ivaničová, Zuzana; Jakobson, Irena; Reis, Diana; Šafář, Jan; Milec, Zbyněk; Abrouk, Michael; Doležel, Jaroslav; Järve, Kadri; Valárik, Miroslav

    2016-09-25

    Flowering time variation was identified within a mapping population of doubled haploid lines developed from a cross between the introgressive line 8.1 and spring bread wheat cv. Tähti. The line 8.1 carried introgressions from tetraploid Triticum militinae in the cv. Tähti genetic background on chromosomes 1A, 2A, 4A, 5A, 7A, 1B and 5B. The most significant QTL for the flowering time variation was identified within the introgressed region on chromosome 5A and its largest effect was associated with the VRN-A1 locus, accounting for up to 70% of phenotypic variance. The allele of T. militinae origin was designated as VRN-A1f-like. The effect of the VRN-A1f-like allele was verified in two other mapping populations. QTL analysis identified that in cv. Tähti and cv. Mooni genetic background, VRN-A1f-like allele incurred a delay of 1.9-18.6 days in flowering time, depending on growing conditions. Sequence comparison of the VRN-A1f-like and VRN-A1a alleles from the parental lines of the mapping populations revealed major mutations in the promoter region as well as in the first intron, including insertion of a MITE element and a large deletion. The sequence variation allowed construction of specific diagnostic PCR markers for VRN-A1f-like allele determination. Identification and quantification of the effect of the VRN-A1f-like allele offers a useful tool for wheat breeding and for studying fine-scale regulation of flowering pathways in wheat. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Novel Hypomorphic Alleles of the Mouse Tyrosinase Gene Induced by CRISPR-Cas9 Nucleases Cause Non-Albino Pigmentation Phenotypes.

    Science.gov (United States)

    Challa, Anil K; Boitet, Evan R; Turner, Ashley N; Johnson, Larry W; Kennedy, Daniel; Downs, Ethan R; Hymel, Katherine M; Gross, Alecia K; Kesterson, Robert A

    2016-01-01

    Tyrosinase is a key enzyme in melanin biosynthesis. Mutations in the gene encoding tyrosinase (Tyr) cause oculocutaneous albinism (OCA1) in humans. Alleles of the Tyr gene have been useful in studying pigment biology and coat color formation. Over 100 different Tyr alleles have been reported in mice, of which ≈24% are spontaneous mutations, ≈60% are radiation-induced, and the remaining alleles were obtained by chemical mutagenesis and gene targeting. Therefore, most mutations were random and could not be predicted a priori. Using the CRISPR-Cas9 system, we targeted two distinct regions of exon 1 to induce pigmentation changes and used an in vivo visual phenotype along with heteroduplex mobility assays (HMA) as readouts of CRISPR-Cas9 activity. Most of the mutant alleles result in complete loss of tyrosinase activity leading to an albino phenotype. In this study, we describe two novel in-frame deletion alleles of Tyr, dhoosara (Sanskrit for gray) and chandana (Sanskrit for sandalwood). These alleles are hypomorphic and show lighter pigmentation phenotypes of the body and eyes. This study demonstrates the utility of CRISPR-Cas9 system in generating domain-specific in-frame deletions and helps gain further insights into structure-function of Tyr gene.

  13. Novel Hypomorphic Alleles of the Mouse Tyrosinase Gene Induced by CRISPR-Cas9 Nucleases Cause Non-Albino Pigmentation Phenotypes.

    Directory of Open Access Journals (Sweden)

    Anil K Challa

    Full Text Available Tyrosinase is a key enzyme in melanin biosynthesis. Mutations in the gene encoding tyrosinase (Tyr cause oculocutaneous albinism (OCA1 in humans. Alleles of the Tyr gene have been useful in studying pigment biology and coat color formation. Over 100 different Tyr alleles have been reported in mice, of which ≈24% are spontaneous mutations, ≈60% are radiation-induced, and the remaining alleles were obtained by chemical mutagenesis and gene targeting. Therefore, most mutations were random and could not be predicted a priori. Using the CRISPR-Cas9 system, we targeted two distinct regions of exon 1 to induce pigmentation changes and used an in vivo visual phenotype along with heteroduplex mobility assays (HMA as readouts of CRISPR-Cas9 activity. Most of the mutant alleles result in complete loss of tyrosinase activity leading to an albino phenotype. In this study, we describe two novel in-frame deletion alleles of Tyr, dhoosara (Sanskrit for gray and chandana (Sanskrit for sandalwood. These alleles are hypomorphic and show lighter pigmentation phenotypes of the body and eyes. This study demonstrates the utility of CRISPR-Cas9 system in generating domain-specific in-frame deletions and helps gain further insights into structure-function of Tyr gene.

  14. Frequency of the GPR7 Tyr135Phe allelic variant in lean and obese subjects.

    Science.gov (United States)

    Pelosini, C; Maffei, M; Ceccarini, G; Marchi, M; Marsili, A; Galli, G; Scartabelli, G; Tamberi, A; Latrofa, F; Fierabracci, P; Vitti, P; Pinchera, A; Santini, F

    2013-10-01

    GPR7, the endogenous coupled receptor for neuropeptide B and neuropeptide W, is expressed in several regions of the central nervous system, which are involved in the regulation of feeding behavior. GPR7 affects the regulation of energy balance through a mechanism independent of leptin and melanocortin pathways. Aim of this study was to investigate whether GPR7 gene mutations can be detected in human subjects and, in that event, if they are differently distributed among lean and obese subjects. The coding region of GPR7 were sequenced in 150 obese patients and 100 normal-weight unrelated controls. Functional studies of the allelic variants were performed. One genetic GPR7 variant was found (Tyr135Phe - rs33977775) in obese subjects (13.3%) and lean control (25%). Functional studies did not reveal significant differences between the wild type and the Tyr135Phe allelic variants in their NPW-mediated capacity to inhibit forskolin-induced cAMP production. Screening of GPR7 gene mutations among lean and obese subjects revealed a Tyr135Phe allelic variant that was fairly common in the study population. As indicated by in vitro and in silico studies, this variant is unlikely to cause a functional derangement of the receptor.

  15. Specific Silencing of L392V PSEN1 Mutant Allele by RNA Interference

    Directory of Open Access Journals (Sweden)

    Malgorzata Sierant

    2011-01-01

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

  16. Beta2-adrenergic receptor allele frequencies in the Quechua, a high altitude native population.

    Science.gov (United States)

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

    2000-03-01

    The beta2-adrenergic receptor is involved in the control of numerous physiological processes and, as the primary catecholamine receptor in the lungs, is of particular importance in the regulation of pulmonary function. There are several polymorphic loci in the beta2-adrenergic receptor gene that have alleles that alter receptor function, including two (A/G46, G/C79) that increase agonist sensitivity. As such a phenotype may increase vaso and bronchial dilation, thereby facilitating air and blood flow through the lungs, we hypothesized that selection may have favoured these alleles in high altitude populations as part of an adaptive strategy to deal with the hypoxic conditions characteristic of such environments. We tested this hypothesis by determining the allele frequencies for these two polymorphisms, as well one additional missense mutation (C/T491) and two silent mutations (G/A252 and C/A523) in 63 Quechua speaking natives from communities located between 3200 and 4200 m on the Peruvian altiplano. These frequencies were compared with those of two lowland populations, one native American (Na-Dene from the west coast of Canada) and one Caucasian of Western European descent. The Quechua manifest many of the pulmonary characteristics of high altitude populations and differences in allele frequencies between the Quechua and lowlanders could be indicative of a selective advantage conferred by certain genotypes in high altitude environments. Allele frequencies varied between populations at some loci and patterns of linkage disequilibrium differed between the old-world and new-world samples; however, as these populations are not closely related, significant variation would be expected due to stochastic effects alone. Neither of the alleles associated with increased receptor sensitivity (A46, G79) was significantly over-represented in the Quechua compared with either lowland group. The Quechua were monomorphic for the C allele at base 79. This variant has been

  17. Frequency of null allele of Human Leukocyte Antigen-G (HLA-G locus in subjects to recurrent miscarriage

    Directory of Open Access Journals (Sweden)

    Nazila Alizadeh

    2016-07-01

    Full Text Available Background: Human leukocyte antigen-G (HLA-G is a non-classical class I molecule highly expressed by extravillous cytotrophoblast cells. Due to a single base pair deletion, its function can be compensated by other isoforms. Investigating the frequency of null allele in Recurrent Miscarriage (RM subjects could be useful in understanding the relationship between frequency of this allele and RM in a given population. Objective: This study aimed to determine the frequency of HLA-G*0105N null allele and its potential association with down-regulation of HLA-G in subjects with RM. Materials and Methods: Western blotting was used to assess the level of HLA-G protein expression. For investigating the frequency of HLA-G*0105N null allele in RM subjects, PCR-RFLP method was used. Exon 3 of HLA-G gene was amplified by polymerase chain reaction (PCR. Subsequently, PpuM-1 enzyme was employed to digest the PCR products and fragments were analyzed using gel electrophoresis. Results: Digestion using restriction enzyme showed the presence of heterozygous HLA-G*0105N null allele in 10% of the test population. Western blotting results confirmed the decrease in expression of HLA-G in the placental tissue of subjects with RM compared to subjects who could give normal birth. Conclusion: The frequency of heterozygous HLA-G*0105N null allele was high to some extent in subjects with RM. The mutation rate in subjects suggested that there is a significant association between RM and frequency of mutations in this allele.

  18. Frequency of null allele of Human Leukocyte Antigen-G (HLA-G) locus in subjects to recurrent miscarriage

    Science.gov (United States)

    Alizadeh, Nazila; Mosaferi, Elnaz; Farzadi, Laya; Majidi, Jafar; Monfaredan, Amir; Yousefi, Bahman; Baradaran, Behzad

    2016-01-01

    Background: Human leukocyte antigen-G (HLA-G) is a non-classical class I molecule highly expressed by extravillous cytotrophoblast cells. Due to a single base pair deletion, its function can be compensated by other isoforms. Investigating the frequency of null allele in Recurrent Miscarriage (RM) subjects could be useful in understanding the relationship between frequency of this allele and RM in a given population. Objective: This study aimed to determine the frequency of HLA-G*0105N null allele and its potential association with down-regulation of HLA-G in subjects with RM. Materials and Methods: Western blotting was used to assess the level of HLA-G protein expression. For investigating the frequency of HLA-G*0105N null allele in RM subjects, PCR-RFLP method was used. Exon 3 of HLA-G gene was amplified by polymerase chain reaction (PCR). Subsequently, PpuM-1 enzyme was employed to digest the PCR products and fragments were analyzed using gel electrophoresis. Results: Digestion using restriction enzyme showed the presence of heterozygous HLA-G*0105N null allele in 10% of the test population. Western blotting results confirmed the decrease in expression of HLA-G in the placental tissue of subjects with RM compared to subjects who could give normal birth. Conclusion: The frequency of heterozygous HLA-G*0105N null allele was high to some extent in subjects with RM. The mutation rate in subjects suggested that there is a significant association between RM and frequency of mutations in this allele. PMID:27525330

  19. PKD1 Mono-Allelic Knockout Is Sufficient to Trigger Renal Cystogenesis in a Mini-Pig Model

    OpenAIRE

    He, Jin; Li, Qiuyan; Fang, Suyun; Guo, Ying; Liu, Tongxin; Ye, Jianhua; Yu, Zhengquan; Zhang, Ran; Zhao, Yaofeng; Hu, Xiaoxiang; Bai, Xueyuan; Chen, Xiangmei; Li, Ning

    2015-01-01

    PKD1 and PKD2 mutations could lead to autosomal dominant polycystic kidney disease (ADPKD), which afflicts millions of people worldwide. Due to the marked differences in the lifespan, size, anatomy, and physiology from humans, rodent ADPKD models cannot fully mimic the disease. To obtain a large animal model that recapitulates the disease, we constructed a mini-pig model by mono-allelic knockout (KO) of PKD1 using zinc finger nuclease. The mono-allelic KO pigs had lower PKD1 expression than t...

  20. Cancer risk and clinicopathological characteristics of thyroid nodules harboring thyroid-stimulating hormone receptor gene mutations.

    Science.gov (United States)

    Mon, Sann Y; Riedlinger, Gregory; Abbott, Collette E; Seethala, Raja; Ohori, N Paul; Nikiforova, Marina N; Nikiforov, Yuri E; Hodak, Steven P

    2018-05-01

    Thyroid-stimulating hormone receptor (TSHR) gene mutations play a critical role in thyroid cell proliferation and function. They are found in 20%-82% of hyperfunctioning nodules, hyperfunctioning follicular thyroid cancers (FTC), and papillary thyroid cancers (PTC). The diagnostic importance of TSHR mutation testing in fine needle aspiration (FNA) specimens remains unstudied. To examine the association of TSHR mutations with the functional status and surgical outcomes of thyroid nodules, we evaluated 703 consecutive thyroid FNA samples with indeterminate cytology for TSHR mutations using next-generation sequencing. Testing for EZH1 mutations was performed in selected cases. The molecular diagnostic testing was done as part of standard of care treatment, and did not require informed consent. TSHR mutations were detected in 31 (4.4%) nodules and were located in exons 281-640, with codon 486 being the most common. Allelic frequency ranged from 3% to 45%. Of 16 cases (12 benign, 3 FTC, 1 PTC) with surgical correlation, 15 had solitary TSHR mutations and 1 PTC had comutation with BRAF V600E. Hyperthyroidism was confirmed in all 3 FTC (2 overt, 1 subclinical). Of 5 nodules with solitary TSHR mutations detected at high allelic frequency, 3 (60%) were FTC. Those at low allelic frequency (3%-22%) were benign. EZH1 mutations were detected in 2 of 4 TSHR-mutant malignant nodules and neither of 2 benign nodules. We report that TSHR mutations occur in ∼5% thyroid nodules in a large consecutive series with indeterminate cytology. TSHR mutations may be associated with an increased cancer risk when present at high allelic frequency, even when the nodule is hyperfunctioning. Benign nodules were however most strongly correlated with TSHR mutations at low allelic frequency. © 2018 Wiley Periodicals, Inc.

  1. Highly prevalent LIPH founder mutations causing autosomal recessive woolly hair/hypotrichosis in Japan and the genotype/phenotype correlations.

    Directory of Open Access Journals (Sweden)

    Kana Tanahashi

    Full Text Available Mutations in LIPH cause of autosomal recessive woolly hair/hypotrichosis (ARWH, and the 2 missense mutations c.736T>A (p.Cys246Ser and c.742C>A (p.His248Asn are considered prevalent founder mutations for ARWH in the Japanese population. To reveal genotype/phenotype correlations in ARWH cases in Japan and the haplotypes in 14 Japanese patients from 14 unrelated Japanese families. 13 patients had woolly hair, and 1 patient had complete baldness since birth. An LIPH mutation search revealed homozygous c.736T>A mutations in 10 of the patients. Compound heterozygous c.736T>A and c.742C>A mutations were found in 3 of the patients, and homozygous c.742C>A mutation in 1 patient. The phenotype of mild hypotrichosis with woolly hair was restricted to the patients with the homozygous c.736T>A mutation. The severe phenotype of complete baldness was seen in only 1 patient with homozygous c.742C>A. Haplotype analysis revealed that the alleles containing the LIPH c.736T>A mutation had a haplotype identical to that reported previously, although 4 alleles out of 5 chromosomes containing the LIPH c.742C>A mutation had a different haplotype from the previously reported founder allele. These alleles with c.742C>A are thought to be the third founder LIPH mutation causing ARWH. To accurately determine the prevalence of the founder mutations, we investigated allele frequencies of those mutations in 819 Japanese controls. Heterozygous c.736T>A mutations were found in 13 controls (allele frequency: 0.0079; carrier rate: 0.016, and heterozygous c.742C>A mutations were found in 2 controls (allele frequency: 0.0012; carrier rate: 0.0024. In conclusion, this study confirms the more accurate allele frequencies of the pathogenic founder mutations of LIPH and shows that there is a third founder mutation in Japan. In addition, the present findings suggest that the mutation patterns of LIPH might be associated with hypotrichosis severity in ARWH.

  2. The Oenothera plastome mutator: effect of UV irradiation and nitroso-methyl urea on mutation frequencies

    International Nuclear Information System (INIS)

    Sears, B.B.; Sokalski, M.B.

    1991-01-01

    Oenothera plants homozygous for a recessive plastome mutator allele (pm) showed spontaneous mutation frequencies for plastome genes that are 200-fold higher than spontaneous levels. Mutations occurred at high frequencies in plants grown in the field, in a glasshouse, or as leaf tip cultures under fluorescent light, indicating that the plastome mutator activity is UV-independent. However, the chlorotic sectors became visible at an earlier stage of development when seedlings were irradiated, compared to seedlings that were not exposed to UV. These results imply that the rate of sorting-out was increased by the irradiation treatment, possibly due to a decrease in the effective number of multiplication-competent plastids, or a reduction in the extent of cytoplasmic mixing. Nitroso-methyl urea treatment of seeds had a dramatic effect on mutation frequency in both wild-type and plastome mutator samples. When the background mutation rates were low, the combination of the plastome mutator nucleus and the chemical mutagenesis treatment resulted in a synergistic effect, suggesting that the plastome mutator may involve a cpDNA repair pathway. (author)

  3. Novel deletion alleles carrying CYP21A1P/A2 chimeric genes in Brazilian patients with 21-hydroxylase deficiency

    Directory of Open Access Journals (Sweden)

    Guerra-Júnior Gil

    2010-06-01

    Full Text Available Abstract Background Congenital adrenal hyperplasia due to 21-hydroxylase deficiency is caused by deletions, large gene conversions or mutations in CYP21A2 gene. The human gene is located at 6p21.3 within a locus containing the genes for putative serine/threonine Kinase RP, complement C4, steroid 21-hydroxylase CYP21 tenascin TNX, normally, in a duplicated cluster known as RCCX module. The CYP21 extra copy is a pseudogene (CYP21A1P. In Brazil, 30-kb deletion forming monomodular alleles that carry chimeric CYP21A1P/A2 genes corresponds to ~9% of disease-causing alleles. Such alleles are considered to result from unequal crossovers within the bimodular C4/CYP21 locus. Depending on the localization of recombination breakpoint, different alleles can be generated conferring the locus high degree of allelic variability. The purpose of the study was to investigate the variability of deleted alleles in patients with 21-hydroxylase deficiency. Methods We used different techniques to investigate the variability of 30-kb deletion alleles in patients with 21-hydroxylase deficiency. Alleles were first selected after Southern blotting. The composition of CYP21A1P/A2 chimeric genes was investigated by ASO-PCR and MLPA analyses followed by sequencing to refine the location of recombination breakpoints. Twenty patients carrying at least one allele with C4/CYP21 30-kb deletion were included in the study. Results An allele carrying a CYP21A1P/A2 chimeric gene was found unusually associated to a C4B/C4A Taq I 6.4-kb fragment, generally associated to C4B and CYP21A1P deletions. A novel haplotype bearing both p.P34L and p.H62L, novel and rare mutations, respectively, was identified in exon 1, however p.P30L, the most frequent pseudogene-derived mutation in this exon, was absent. Four unrelated patients showed this haplotype. Absence of p.P34L in CYP21A1P of normal controls indicated that it is not derived from pseudogene. In addition, the combination of different

  4. Two domain-disrupted hda6 alleles have opposite epigenetic effects on transgenes and some endogenous targets

    KAUST Repository

    Zhang, ShouDong; Zhan, Xiangqiang; Xu, Xiaoming; Cui, Peng; Zhu, Jian-Kang; Xia, Yiji; Xiong, Liming

    2015-01-01

    HDA6 is a RPD3-like histone deacetylase. In Arabidopsis, it mediates transgene and some endogenous target transcriptional gene silencing (TGS) via histone deacetylation and DNA methylation. Here, we characterized two hda6 mutant alleles that were recovered as second-site suppressors of the DNA demethylation mutant ros1–1. Although both alleles derepressed 35S::NPTII and RD29A::LUC in the ros1–1 background, they had distinct effects on the expression of these two transgenes. In accordance to expression profiles of two transgenes, the alleles have distinct opposite methylation profiles on two reporter gene promoters. Furthermore, both alleles could interact in vitro and in vivo with the DNA methyltransferase1 with differential interactive strength and patterns. Although these alleles accumulated different levels of repressive/active histone marks, DNA methylation but not histone modifications in the two transgene promoters was found to correlate with the level of derepression of the reporter genes between the two had6 alleles. Our study reveals that mutations in different domains of HDA6 convey different epigenetic status that in turn controls the expression of the transgenes as well as some endogenous loci.

  5. Two domain-disrupted hda6 alleles have opposite epigenetic effects on transgenes and some endogenous targets

    KAUST Repository

    Zhang, ShouDong

    2015-12-15

    HDA6 is a RPD3-like histone deacetylase. In Arabidopsis, it mediates transgene and some endogenous target transcriptional gene silencing (TGS) via histone deacetylation and DNA methylation. Here, we characterized two hda6 mutant alleles that were recovered as second-site suppressors of the DNA demethylation mutant ros1–1. Although both alleles derepressed 35S::NPTII and RD29A::LUC in the ros1–1 background, they had distinct effects on the expression of these two transgenes. In accordance to expression profiles of two transgenes, the alleles have distinct opposite methylation profiles on two reporter gene promoters. Furthermore, both alleles could interact in vitro and in vivo with the DNA methyltransferase1 with differential interactive strength and patterns. Although these alleles accumulated different levels of repressive/active histone marks, DNA methylation but not histone modifications in the two transgene promoters was found to correlate with the level of derepression of the reporter genes between the two had6 alleles. Our study reveals that mutations in different domains of HDA6 convey different epigenetic status that in turn controls the expression of the transgenes as well as some endogenous loci.

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

    African Journals Online (AJOL)

    SERVER

    2008-04-17

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

  7. A new electrophoresis technique to separate microsatellite alleles ...

    African Journals Online (AJOL)

    A new electrophoresis technique to separate microsatellite alleles* ... African Journal of Biotechnology ... with the CEQTM 8000 Genetic Analysis System and ABI 3130xl DNA Sequencer easily separated products and determined allelic size, ...

  8. Allele specific expression and methylation in the bumblebee, Bombus terrestris

    Directory of Open Access Journals (Sweden)

    Zoë Lonsdale

    2017-09-01

    Full Text Available The social hymenoptera are emerging as models for epigenetics. DNA methylation, the addition of a methyl group, is a common epigenetic marker. In mammals and flowering plants methylation affects allele specific expression. There is contradictory evidence for the role of methylation on allele specific expression in social insects. The aim of this paper is to investigate allele specific expression and monoallelic methylation in the bumblebee, Bombus terrestris. We found nineteen genes that were both monoallelically methylated and monoallelically expressed in a single bee. Fourteen of these genes express the hypermethylated allele, while the other five express the hypomethylated allele. We also searched for allele specific expression in twenty-nine published RNA-seq libraries. We found 555 loci with allele-specific expression. We discuss our results with reference to the functional role of methylation in gene expression in insects and in the as yet unquantified role of genetic cis effects in insect allele specific methylation and expression.

  9. Comparative frequency and allelic distribution of ABO and Rh (D ...

    African Journals Online (AJOL)

    Gourab Dewan

    2015-02-18

    Feb 18, 2015 ... desh and having borders with India and Myanmar (Fig. 1). It is a hilly area with ..... calculated allelic frequencies for ABO/Rh systems previously. Therefore, allelic .... in backward caste population of Uttar Pradesh, India. Not Sci.

  10. Association mapping and favourable QTL alleles for fibre quality ...

    Indian Academy of Sciences (India)

    Cheng-Guang Dong

    A total of 201 markers were polymorphic and generated 394 allele loci, and 403 ... identified as containing favourable allele loci related to fibre quality traits. The identified .... environment. Field management followed respective local practices.

  11. Dominant hemimelia and En-1 on mouse chromosome 1 are not allelic.

    Science.gov (United States)

    Higgins, M; Hill, R E; West, J D

    1992-08-01

    Previous studies have shown that En-1, a homeobox-containing gene, maps close to or at the Dh locus in the mouse. Since homeobox-containing genes are key genes in the control of development the close proximity of En-1 to the developmentally significant gene Dh raised the possibility that the Dh mutation represented a mutant allele of En-1. A genetic analysis involving En-1, Dh, and other chromosome 1 markers (Emv-17, ln and Pep-3) shows that although Dh and En-1 are closely linked they are separable by recombination (4/563). The likely gene order and recombination frequencies of these loci are: ln (5.2 +/- 0.9) Emv-17 (1.1 +/- 0.4) Dh (0.7 +/- 0.4) En-1 (3.0 +/- 0.7) Pep-3. This shows that Dh is not a mutant allele of En-1.

  12. Allele and genotype frequencies of -β lactoglobulin gene in Iranian ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-04

    Aug 4, 2009 ... Blood samples were supplied from 80 Najdi cattle and 80 buffalo from different cities of Khouzestan province. ... The allele B of β-Lactoglobulin occurred at a higher frequency than the allele A in both. Najdi cattle and buffalo. .... that of the B allele in both groups of animals studied. Expected heterozygosity ...

  13. Directional Positive Selection on an Allele of Arbitrary Dominance

    OpenAIRE

    Teshima, Kosuke M.; Przeworski, Molly

    2006-01-01

    Most models of positive directional selection assume codominance of the beneficial allele. We examine the importance of this assumption by implementing a coalescent model of positive directional selection with arbitrary dominance. We find that, for a given mean fixation time, a beneficial allele has a much weaker effect on diversity at linked neutral sites when the allele is recessive.

  14. New mutations affecting induced mutagenesis in yeast.

    Science.gov (United States)

    Lawrence, C W; Krauss, B R; Christensen, R B

    1985-01-01

    Previously isolated mutations in baker's yeast, Saccharomyces cerevisiae, that impair induced mutagenesis were all identified with the aid of tests that either exclusively or predominantly detect base-pair substitutions. To avoid this bias, we have screened 11 366 potentially mutant clones for UV-induced reversion of the frameshift allele, his4-38, and have identified 10 mutants that give much reduced yields of revertants. Complementation and recombination tests show that 6 of these carry mutations at the previously known REV1, REV1 and REV3 loci, while the remaining 4 define 3 new genes, REV4 (2 mutations), REV5 and REV6. The rev4 mutations are readily suppressed in many genetic backgrounds and, like the rev5 mutation, impart only a limited deficiency for induced mutagenesis: it is likely, therefore that the REV4+ and REV5+ gene functions are only remotely concerned with this process. The rev6 mutants have a more general deficiency, however, as well as marked sensitivity to UV and an increased spontaneous mutation rate, properties that suggest the REV6 gene is directly involved in mutation induction. The REV5 gene is located about 1 cM proximal to CYC1 on chromosome X.

  15. [Cloning and sequencing of KIR2DL1 framework gene cDNA and identification of a novel allele].

    Science.gov (United States)

    Sun, Ge; Wang, Chang; Zhen, Jianxin; Zhang, Guobin; Xu, Yunping; Deng, Zhihui

    2016-10-01

    To develop an assay for cDNA cloning and haplotype sequencing of KIR2DL1 framework gene and determine the genotype of an ethnic Han from southern China. Total RNA was isolated from peripheral blood sample, and complementary DNA (cDNA) transcript was synthesized by RT-PCR. The entire coding sequence of the KIR2DL1 framework gene was amplified with a pair of KIR2DL1-specific PCR primers. The PCR products with a length of approximately 1.2 kb were then subjected to cloning and haplotype sequencing. A specific target fragment of the KIR2DL1 framework gene was obtained. Following allele separation, a wild-type KIR2DL1*00302 allele and a novel variant allele, KIR2DL1*031, were identified. Sequence alignment with KIR2DL1 alleles from the IPD-KIR Database showed that the novel allele KIR2DL1*031 has differed from the closest allele KIR2DL1*00302 by a non-synonymous mutation at CDS nt 188A>G (codon 42 GAG>GGG) in exon 4, which has caused an amino acid change Glu42Gly. The sequence of the novel allele KIR2DL1*031 was submitted to GenBank under the accession number KP025960 and to the IPD-KIR Database under the submission number IWS40001982. A name KIR2DL1*031 has been officially assigned by the World Health Organization (WHO) Nomenclature Committee. An assay for cDNA cloning and haplotype sequencing of KIR2DL1 has been established, which has a broad applications in KIR studies at allelic level.

  16. Animal products and K-ras codon 12 and 13 mutations in colon carcinomas

    NARCIS (Netherlands)

    Kampman, E.; Voskuil, D.W.; Kraats, A.A. van; Balder, H.F.; Muijen, G.N.P. van; Goldbohm, R.A.; Veer, P. van 't

    2000-01-01

    K-ras gene mutations (codons 12 and 13) were determined by PCR-based mutant allele-specific amplification (MASA) in tumour tissue of 185 colon cancer patients: 36% harboured mutations, of which 82% were located in codon 12. High intakes of animal protein, calcium and poultry were differently

  17. H63D mutation in HFE gene is common in Indians and is associated ...

    Indian Academy of Sciences (India)

    HH affects predominantly people of northern European origin and is often ... mutation with the C282Y mutation is a known risk factor for iron overload ... or has low allele frequencies in non-Caucasian populations,. i.e. African ... who were ascertained through self-reported questionnaire. ... confidence limits of the D statistic.

  18. Haplotype structure in Ashkenazi Jewish BRCA1 and BRCA2 mutation carriers

    NARCIS (Netherlands)

    Im, Kate M.; Kirchhoff, Tomas; Wang, Xianshu; Green, Todd; Chow, Clement Y.; Vijai, Joseph; Korn, Joshua; Gaudet, Mia M.; Fredericksen, Zachary; Shane Pankratz, V.; Guiducci, Candace; Crenshaw, Andrew; McGuffog, Lesley; Kartsonaki, Christiana; Morrison, Jonathan; Healey, Sue; Sinilnikova, Olga M.; Mai, Phuong L.; Greene, Mark H.; Piedmonte, Marion; Rubinstein, Wendy S.; Hogervorst, Frans B.; Rookus, Matti A.; Collée, J. Margriet; Hoogerbrugge, Nicoline; van Asperen, Christi J.; Meijers-Heijboer, Hanne E. J.; van Roozendaal, Cees E.; Caldes, Trinidad; Perez-Segura, Pedro; Jakubowska, Anna; Lubinski, Jan; Huzarski, Tomasz; Blecharz, Paweł; Nevanlinna, Heli; Aittomäki, Kristiina; Lazaro, Conxi; Blanco, Ignacio; Barkardottir, Rosa B.; Montagna, Marco; D'Andrea, Emma; Devilee, Peter; Olopade, Olufunmilayo I.; Neuhausen, Susan L.; Peissel, Bernard; Bonanni, Bernardo; Peterlongo, Paolo; Singer, Christian F.; Rennert, Gad; Lejbkowicz, Flavio; Andrulis, Irene L.; Glendon, Gord; Ozcelik, Hilmi; Toland, Amanda Ewart; Caligo, Maria Adelaide; Beattie, Mary S.; Chan, Salina; Domchek, Susan M.; Nathanson, Katherine L.; Rebbeck, Timothy R.; Phelan, Catherine; Narod, Steven; John, Esther M.; Hopper, John L.; Buys, Saundra S.; Daly, Mary B.; Southey, Melissa C.; Terry, Mary-Beth; Tung, Nadine; Hansen, Thomas V. O.; Osorio, Ana; Benitez, Javier; Durán, Mercedes; Weitzel, Jeffrey N.; Garber, Judy; Hamann, Ute; Peock, Susan; Cook, Margaret; Oliver, Clare T.; Frost, Debra; Platte, Radka; Evans, D. Gareth; Eeles, Ros; Izatt, Louise; Paterson, Joan; Brewer, Carole; Hodgson, Shirley; Morrison, Patrick J.; Porteous, Mary; Walker, Lisa; Rogers, Mark T.; Side, Lucy E.; Godwin, Andrew K.; Schmutzler, Rita K.; Wappenschmidt, Barbara; Laitman, Yael; Meindl, Alfons; Deissler, Helmut; Varon-Mateeva, Raymonda; Preisler-Adams, Sabine; Kast, Karin; Venat-Bouvet, Laurence; Stoppa-Lyonnet, Dominique; Chenevix-Trench, Georgia; Easton, Douglas F.; Klein, Robert J.; Daly, Mark J.; Friedman, Eitan; Dean, Michael; Clark, Andrew G.; Altshuler, David M.; Antoniou, Antonis C.; Couch, Fergus J.; Offit, Kenneth; Gold, Bert; Gauthier-Villars, Marion; Houdayer, Claude; Moncoutier, Virginie; Belotti, Muriel; de Pauw, Antoine; Bressac-de-Paillerets, Brigitte; Remenieras, Audrey; Byrde, Véronique; Caron, Olivier; Lenoir, Gilbert; Bignon, Yves-Jean; Uhrhammer, Nancy; Lasset, Christine; Bonadona, Valérie; Hardouin, Agnès; Berthet, Pascaline; Sobol, Hagay; Bourdon, Violaine; Noguchi, Tetsuro; Eisinger, François; Coulet, Florence; Colas, Chrystelle; Soubrier, Florent; Coupier, Isabelle; Peyrat, Jean-Philippe; Fournier, Joëlle; Révillion, Françoise; Vennin, Philippe; Adenis, Claude; Rouleau, Etienne; Lidereau, Rosette; Demange, Liliane; Nogues, Catherine; Muller, Danièle; Fricker, Jean-Pierre; Longy, Michel; Sevenet, Nicolas; Toulas, Christine; Guimbaud, Rosine; Gladieff, Laurence; Feillel, Viviane; Leroux, Dominique; Dreyfus, Hélène; Rebischung, Christine; Cassini, Cécile; Faivre, Laurence; Prieur, Fabienne; Ferrer, Sandra Fert; Frénay, Marc; Vénat-Bouvet, Laurence; Lynch, Henry T.; Thorne, Heather; Niedermayr, Eveline; Pierotti, Marco; Manoukian, Siranoush; Zaffaroni, Daniela; Ripamonti, Carla B.; Radice, Paolo; Barile, Monica; Bernard, Loris; Karlsson, Per; Nordling, Margareta; Bergman, Annika; Einbeigi, Zakaria; Stenmark-Askmalm, Marie; Liedgren, Sigrun; Borg, Åke; Loman, Niklas; Olsson, Håkan; Kristoffersson, Ulf; Jernström, Helena; Harbst, Katja; Henriksson, Karin; Lindblom, Annika; Arver, Brita; von Wachenfeldt, Anna; Liljegren, Annelie; Barbany-Bustinza, Gisela; Rantala, Johanna; Melin, Beatrice; Grönberg, Henrik; Stattin, Eva-Lena; Emanuelsson, Monica; Ehrencrona, Hans; Brandell, Richard Rosenquist; Dahl, Niklas; Hogervorst, F. B. L.; Verhoef, S.; Verheus, M.; van 't Veer, L. J.; van Leeuwen, F. E.; Rookus, M. A.; Collée, M.; van den Ouweland, A. M. W.; Jager, A.; Hooning, M. J.; Tilanus-Linthorst, M. M. A.; Seynaeve, C.; van Asperen, C. J.; Wijnen, J. T.; Vreeswijk, M. P.; Tollenaar, R. A.; Devilee, P.; Ligtenberg, M. J.; Hoogerbrugge, N.; Ausems, M. G.; van der Luijt, R. B.; Aalfs, C. M.; van Os, T. A.; Gille, J. J. P.; Waisfisz, Q.; Gomez-Garcia, E. B.; van Roozendaal, C. E.; Blok, Marinus J.; Caanen, B.; Oosterwijk, J. C.; van der Hout, A. H.; Mourits, M. J.; Vasen, H. F.; Miedzybrodzka, Zosia; Gregory, Helen; Morrison, Patrick; Jeffers, Lisa; Cole, Trevor; Ong, Kai-Ren; Hoffman, Jonathan; Donaldson, Alan; James, Margaret; Downing, Sarah; Taylor, Amy; Murray, Alexandra; McCann, Emma; Kennedy, M. John; Barton, David; Drummond, Sarah; Kivuva, Emma; Searle, Anne; Goodman, Selina; Hill, Kathryn; Davidson, Rosemarie; Murday, Victoria; Bradshaw, Nicola; Snadden, Lesley; Longmuir, Mark; Watt, Catherine; Gibson, Sarah; Haque, Eshika; Tobias, Ed; Duncan, Alexis; Jacobs, Chris; Langman, Caroline; Whaite, Anna; Dorkins, Huw; Randhawa, Kashmir; Barwell, Julian; Patel, Nafisa; Adlard, Julian; Chu, Carol; Miller, Julie; Ellis, Ian; Houghton, Catherine; Lalloo, Fiona; Taylor, Jane; Side, Lucy; Male, Alison; Berlin, Cheryl; Eason, Jacqueline; Collier, Rebecca; Douglas, Fiona; Claber, Oonagh; Jobson, Irene; McLeod, Diane; Halliday, Dorothy; Durell, Sarah; Stayner, Barbara; Shanley, Susan; Rahman, Nazneen; Houlston, Richard; Bancroft, Elizabeth; D'Mello, Lucia; Page, Elizabeth; Ardern-Jones, Audrey; Kohut, Kelly; Wiggins, Jennifer; Castro, Elena; Mitra, Anita; Robertson, Lisa; Cook, Jackie; Quarrell, Oliver; Bardsley, Cathryn; Brice, Glen; Winchester, Lizzie; Eddy, Charlotte; Tripathi, Vishakha; Attard, Virginia; Eccles, Diana; Lucassen, Anneke; Crawford, Gillian; McBride, Donna; Smalley, Sarah

    2011-01-01

    Three founder mutations in BRCA1 and BRCA2 contribute to the risk of hereditary breast and ovarian cancer in Ashkenazi Jews (AJ). They are observed at increased frequency in the AJ compared to other BRCA mutations in Caucasian non-Jews (CNJ). Several authors have proposed that elevated allele

  19. Analysis of time of death of prenatally lethal Steeloid mutations

    International Nuclear Information System (INIS)

    Rinchik, E.M.; Cummings, C.C.; Bangham, J.W.; Hunsicker, P.R.; Phipps, E.L.; Stelzner, K.F.

    1987-01-01

    Deletion mutations have been extremely useful in initiating the functional and molecular dissections of regions of the mouse genome. For the d-se and c regions, for example, it was observed that radiation mutations carrying lethal factors separable, by complementation analysis, from the primary d, se, or c mutation itself, could often be associated at both the genetic and molecular levels with multilocus chromosomal deletions. Since many of the Oak Ridge Sld mutations arose in radiation mutagenesis experiments, a substantial number may carry chromosomal deletions that involve the Sl locus in chromosome 10. Because of the great value of deletion mutations for the genetic and molecular analysis of chromosomal regions and complex genetic loci, they have initiated a series of experiments designed to test whether radiation-induced Sld mutations carry other lethal factors, in addition to the lethality caused by severe alleles of the Sl locus itself, as one prescreen for identifying Sld's that are caused by deletions

  20. RADIA: RNA and DNA integrated analysis for somatic mutation detection.

    Directory of Open Access Journals (Sweden)

    Amie J Radenbaugh

    Full Text Available The detection of somatic single nucleotide variants is a crucial component to the characterization of the cancer genome. Mutation calling algorithms thus far have focused on comparing the normal and tumor genomes from the same individual. In recent years, it has become routine for projects like The Cancer Genome Atlas (TCGA to also sequence the tumor RNA. Here we present RADIA (RNA and DNA Integrated Analysis, a novel computational method combining the patient-matched normal and tumor DNA with the tumor RNA to detect somatic mutations. The inclusion of the RNA increases the power to detect somatic mutations, especially at low DNA allelic frequencies. By integrating an individual's DNA and RNA, we are able to detect mutations that would otherwise be missed by traditional algorithms that examine only the DNA. We demonstrate high sensitivity (84% and very high precision (98% and 99% for RADIA in patient data from endometrial carcinoma and lung adenocarcinoma from TCGA. Mutations with both high DNA and RNA read support have the highest validation rate of over 99%. We also introduce a simulation package that spikes in artificial mutations to patient data, rather than simulating sequencing data from a reference genome. We evaluate sensitivity on the simulation data and demonstrate our ability to rescue back mutations at low DNA allelic frequencies by including the RNA. Finally, we highlight mutations in important cancer genes that were rescued due to the incorporation of the RNA.

  1. Laser desorption mass spectrometry for point mutation detection

    Energy Technology Data Exchange (ETDEWEB)

    Taranenko, N.I.; Chung, C.N.; Zhu, Y.F. [Oak Ridge National Lab., TN (United States)] [and others

    1996-10-01

    A point mutation can be associated with the pathogenesis of inherited or acquired diseases. Laser desorption mass spectrometry coupled with allele specific polymerase chain reaction (PCR) was first used for point mutation detection. G551D is one of several mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene present in 1-3% of the mutant CFTR alleles in most European populations. In this work, two different approaches were pursued to detect G551D point mutation in the cystic fibrosis gene. The strategy is to amplify the desired region of DNA template by PCR using two primers that overlap one base at the site of the point mutation and which vary in size. If the two primers based on the normal sequence match the target DNA sequence, a normal PCR product will be produced. However, if the alternately sized primers that match the mutant sequence recognize the target DNA, an abnormal PCR product will be produced. Thus, the mass spectrometer can be used to identify patients that are homozygous normal, heterozygous for a mutation or homozygous abnormal at a mutation site. Another approach to identify similar mutations is the use of sequence specific restriction enzymes which respond to changes in the DNA sequence. Mass spectrometry is used to detect the length of the restriction fragments generated by digestion of a PCR generated target fragment. 21 refs., 10 figs., 2 tabs.

  2. Laser desorption mass spectrometry for point mutation detection

    Energy Technology Data Exchange (ETDEWEB)

    Taranenko, N.I.; Chung, C.N.; Zhu, Y.F. [Oak Ridge National Lab., TN (United States)] [and others

    1996-12-31

    A point mutation can be associated with the pathogenesis of inherited or acquired diseases. Laser desorption mass spectrometry coupled with allele specific polymerase chain reaction (PCR) was first used for point mutation detection. G551D is one of several mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene present in 1-3% of the mutant CFTR alleles in most European populations. In this work, two different approaches were pursued to detect G551D point mutation in the cystic fibrosis gene. The strategy is to amplify the desired region of DNA template by PCR using two primers that overlap one base at the site of the point mutation and which vary in size. If the two primers based on the normal sequence match the target DNA sequence, a normal PCR product will be produced. However, if the alternately sized primers that match the mutant sequence recognize the target DNA, an abnormal PCR product will be produced. Thus, the mass spectrometer can be used to identify patients that are homozygous normal, heterozygous for a mutation or homozygous abnormal at a mutation site. Another approach to identify similar mutations is the use of sequence specific restriction enzymes which respond to changes in the DNA sequence. Mass spectrometry is used to detect the length of the restriction fragments by digestion of a PCR generated target fragment. 21 refs., 10 figs., 2 tabs.

  3. The Analysis of A Frequent TMPRSS3 Allele Containing P.V116M and P.V291L in A Cis Configuration among Deaf Koreans

    Directory of Open Access Journals (Sweden)

    Ah Reum Kim

    2017-10-01

    Full Text Available We performed targeted re-sequencing to identify the genetic etiology of early-onset postlingual deafness and encountered a frequent TMPRSS3 allele harboring two variants in a cis configuration. We aimed to evaluate the pathogenicity of the allele. Among 88 cochlear implantees with autosomal recessive non-syndromic hearing loss, subjects with GJB2 and SLC26A4 mutations were excluded. Thirty-one probands manifesting early-onset postlingual deafness were sorted. Through targeted re-sequencing, we detected two families with a TMPRSS3 mutant allele containing p.V116M and p.V291L in a cis configuration, p.[p.V116M; p.V291L]. A minor allele frequency was calculated and proteolytic activity was measured. A p.[p.V116M; p.V291L] allele demonstrated a significantly higher frequency compared to normal controls and merited attention due to its high frequency (4.84%, 3/62. The first family showed a novel deleterious splice site variant—c.783-1G>A—in a trans allele, while the other showed homozygosity. The progression to deafness was noted within the first decade, suggesting DFNB10. The proteolytic activity was significantly reduced, confirming the severe pathogenicity. This frequent mutant allele significantly contributes to early-onset postlingual deafness in Koreans. For clinical implication and proper auditory rehabilitation, it is important to pay attention to this allele with a severe pathogenic potential.

  4. Null missense ABCR (ABCA4) mutations in a family with stargardt disease and retinitis pigmentosa.

    Science.gov (United States)

    Shroyer, N F; Lewis, R A; Yatsenko, A N; Lupski, J R

    2001-11-01

    To determine the type of ABCR mutations that segregate in a family that manifests both Stargardt disease (STGD) and retinitis pigmentosa (RP), and the functional consequences of the underlying mutations. Direct sequencing of all 50 exons and flanking intronic regions of ABCR was performed for the STGD- and RP-affected relatives. RNA hybridization, Western blot analysis, and azido-adenosine triphosphate (ATP) labeling was used to determine the effect of disease-associated ABCR mutations in an in vitro assay system. Compound heterozygous missense mutations were identified in patients with STGD and RP. STGD-affected individual AR682-03 was compound heterozygous for the mutation 2588G-->C and a complex allele, [W1408R; R1640W]. RP-affected individuals AR682-04 and-05 were compound heterozygous for the complex allele [W1408R; R1640W] and the missense mutation V767D. Functional analysis of the mutation V767D by Western blot and ATP binding revealed a severe reduction in protein expression. In vitro analysis of ABCR protein with the mutations W1408R and R1640W showed a moderate effect of these individual mutations on expression and ATP-binding; the complex allele [W1408R; R1640W] caused a severe reduction in protein expression. These data reveal that missense ABCR mutations may be associated with RP. Functional analysis reveals that the RP-associated missense ABCR mutations are likely to be functionally null. These studies of the complex allele W1408R; R1640W suggest a synergistic effect of the individual mutations. These data are congruent with a model in which RP is associated with homozygous null mutations and with the notion that severity of retinal disease is inversely related to residual ABCR activity.

  5. Consequences of Marfan mutations to expression of fibrillin gene and to the structure of microfibrils

    Energy Technology Data Exchange (ETDEWEB)

    Peltonen, L.; Karttunen, L.; Rantamaeki, T. [NPHI, Helsinki (Finland)] [and others

    1994-09-01

    Marfan syndrome (MFS) is a dominantly inherited connective tissue disorder which is caused by mutations in the fibrillin-1 gene (FBN1). Over 40 family-specific FBN1 mutations have been identified. We have characterized 18 different heterozygous mutations including amino acid substitutions, premature stop, and splicing defects leading to deletions or one insertion, and one compound heterozygote with two differently mutated FBN1 alleles inherited from his affected parents. To unravel the consequences of FBN1 mutations to the transcription of FBN1 gene, we have measured the steady state levels of mRNA transcribed from the normal and mutated alleles. The missense mutations do not affect the transcription of the allele while the nonsense mutation leads to lower steady state amount of mutated allele. For the dissection of molecular pathogenesis of FBN1 mutations we have performed rotary shadowing of the microfibrils produced by the cell cultures from MFS patients. The cells from the neonatal patients with established mutations produced only disorganized fibrillin aggregates but no clearly defined microfibrils could be detected, suggesting a major role of this gene region coding for exons 24-26 in stabilization and organization of the bead structure of microfibrils. From the cells of a rare compound heterozygote case carrying two different mutations, no detectable microfibrils could be detected whereas the cells of his parents with heterozygous mutations were able to form identifiable but disorganized microfibrils. In the cells of an MFS case caused by a premature stop removing the C-terminus of fibrillin, the microfibril assembly takes place but the appropriate packing of the microfibrils is disturbed suggesting that C-terminae are actually located within the interbead domain of the microfibrils.

  6. Association studies using family pools of outcrossing crops based on allele-frequency estimates from DNA sequencing

    DEFF Research Database (Denmark)

    Ashraf, Bilal; Jensen, Just; Asp, Torben

    2014-01-01

    effect from F2-family pools was verified and it was shown that the underestimation of the allele effect is correctly described. The optimal design for an association study when sequencing budget would be fixed is obtained using large sample size and lower sequence depth, and using higher SNP density......F2 families are frequently used in breeding of outcrossing species, for instance to obtain trait measurements on plots. We propose to perform association studies by obtaining a matching “family genotype” from sequencing a pooled sample of the family, and to directly use allele frequencies computed...... (resulting in higher LD with causative mutations) and lower sequencing depth. Therefore, association studies using genotyping by sequencing are optimal and use low sequencing depth per sample. The developed framework for association studies using allele frequencies from sequencing can be modified for other...

  7. Associations between mutations and a VNTR in the human phenylalanine hydroxylase gene

    Energy Technology Data Exchange (ETDEWEB)

    Goltsov, A.A.; Eisensmith, R.C.; Woo, S.L.C. (Baylor College of Medicine, Houston, TX (United States)); Konecki, D.S.; Lichter-Konecki, U.

    1992-09-01

    The HindIII RFLP in the human phenylalanine hydroxylase (PAH) gene is caused by the presence of an AT-rich (70%) minisatellite region. This region contains various multiples of 30-bp tandem repeats and is located 3 kb downstream of the final exon of the gene. PCR-mediated amplification of this region from haplotyped PAH chromosomes indicates that the previously reported 4.0-kb HindIII allele contains three of these repeats, while the 4.4-kb HindIII allele contains 12 of these repeats. The 4.2-kb HindIII fragment can contain six, seven, eight, or nine copies of this repeat. These variations permit more detailed analysis of mutant haplotypes 1, 5, 6, and, possibly, others. Kindred analysis in phenylketonuria families demonstrates Mendelian segregation of these VNTR alleles, as well as associations between theses alleles and certain PAH mutations. The R261Q mutation, associated with haplotype 1, is associated almost exclusively with an allele containing eight repeats; the R408W mutation, when occurring on a haplotype 1 background, may also be associated with the eight-repeat VNTR allele. Other PAH mutations associated with haplotype 1, R252W and P281L, do not appear to segregate with specific VNTR alleles. The IVS-10 mutation, when associated with haplotype 6, is associated exclusively with an allele containing seven repeats. The combined use of this VNTR system and the existing RFLP haplotype system will increase the performance of prenatal diagnostic tests based on haplotype analysis. In addition, this VNTR may prove useful in studies concerning the origins and distributions of PAH mutations in different human populations. 32 refs., 3 figs., 3 tabs.

  8. Intragenic haplotype analysis of common HFE mutations in the ...

    Indian Academy of Sciences (India)

    mutation <100 generations ago in the Celtic populations of mainland Europe, with a ... 0.9–5.8%, evidencing regional differences in distribution across the ..... and H63D alleles in the HFE gene among various Jewish ethnic groups in Israel: a ...

  9. CYP3A4*18: it is not rare allele in Japanese population.

    Science.gov (United States)

    Yamamoto, Takehito; Nagafuchi, Nobue; Ozeki, Takeshi; Kubota, Takahiro; Ishikawa, Hiroshi; Ogawa, Seishi; Yamada, Yasuhiko; Hirai, Hisamaru; Iga, Tatsuji

    2003-01-01

    We sequenced all 13 exons of the CYP3A4 gene derived from 48 Japanese subjects. One subject possess the 20070 T>C mutation in the exon 10 (result in leu293Pro substitution, namely CYP3A4(*)18), as heterozygote. Thus, we investigated the frequency of CYP3A4(*)18 in 118 Japanese population using polymerase chain reaction-restriction fragment length polymorphism with Msp I and determined that the frequency of the CYP3A4(*)18 allele was 1.3%.

  10. Induction of Terpene Biosynthesis in Berries of Microvine Transformed with VvDXS1 Alleles

    Directory of Open Access Journals (Sweden)

    Lorenza Dalla Costa

    2018-01-01

    Full Text Available Terpenoids, especially monoterpenes, are major aroma-impact compounds in grape and wine. Previous studies highlighted a key regulatory role for grapevine 1-deoxy-D-xylulose 5-phosphate synthase 1 (VvDXS1, the first enzyme of the methylerythritol phosphate pathway for isoprenoid precursor biosynthesis. Here, the parallel analysis of VvDXS1 genotype and terpene concentration in a germplasm collection demonstrated that VvDXS1 sequence has a very high predictive value for the accumulation of monoterpenes and also has an influence on sesquiterpene levels. A metabolic engineering approach was applied by expressing distinct VvDXS1 alleles in the grapevine model system “microvine” and assessing the effects on downstream pathways at transcriptional and metabolic level in different organs and fruit developmental stages. The underlying goal was to investigate two potential perturbation mechanisms, the former based on a significant over-expression of the wild-type (neutral VvDXS1 allele and the latter on the ex-novo expression of an enzyme with increased catalytic efficiency from the mutated (muscat VvDXS1 allele. The integration of the two VvDXS1 alleles in distinct microvine lines was found to alter the expression of several terpenoid biosynthetic genes, as assayed through an ad hoc developed TaqMan array based on cDNA libraries of four aromatic cultivars. In particular, enhanced transcription of monoterpene, sesquiterpene and carotenoid pathway genes was observed. The accumulation of monoterpenes in ripe berries was higher in the transformed microvines compared to control plants. This effect is predominantly attributed to the improved activity of the VvDXS1 enzyme coded by the muscat allele, whereas the up-regulation of VvDXS1 plays a secondary role in the increase of monoterpenes.

  11. Allelic imbalance and fine mapping of the 17p13.3 subregion in sporadic breast carcinomas

    DEFF Research Database (Denmark)

    Hoff, C; Mollenhauer, J; Waldau, B

    2001-01-01

    Chromosome arm 17p is frequently altered in a variety of human cancers, especially in breast cancer, and allelic imbalances (AIs) in the region 17p13.1 do not always coincide with mutations in the TP53 gene. A second interval that frequently shows AIs at 17p is the chromosomal band 17p13.3. This ......Chromosome arm 17p is frequently altered in a variety of human cancers, especially in breast cancer, and allelic imbalances (AIs) in the region 17p13.1 do not always coincide with mutations in the TP53 gene. A second interval that frequently shows AIs at 17p is the chromosomal band 17p13...

  12. Genetic Analysis of Three Dominant Female-Sterile Mutations Located on the X Chromosome of DROSOPHILA MELANOGASTER

    OpenAIRE

    Busson, D.; Gans, M.; Komitopoulou, K.; Masson, M.

    1983-01-01

    Three dominant female-sterile mutations were isolated following ethyl methanesulfonate (EMS) mutagenesis. Females heterozygous for two of these mutations show atrophy of the ovaries and produce no eggs (ovo D1) or few eggs (ovoD2); females heterozygous for the third mutation, ovoD3, lay flaccid eggs. All three mutations are germ line-dependent and map to the cytological region 4D-E on the X chromosome; they represent a single allelic series. Two doses of the wild-type allele restore fertility...

  13. Cosegregation and functional analysis of mutant ABCR (ABCA4) alleles in families that manifest both Stargardt disease and age-related macular degeneration.

    Science.gov (United States)

    Shroyer, N F; Lewis, R A; Yatsenko, A N; Wensel, T G; Lupski, J R

    2001-11-01

    Mutations in ABCR (ABCA4) have been reported to cause a spectrum of autosomal recessively inherited retinopathies, including Stargardt disease (STGD), cone-rod dystrophy and retinitis pigmentosa. Individuals heterozygous for ABCR mutations may be predisposed to develop the multifactorial disorder age-related macular degeneration (AMD). We hypothesized that some carriers of STGD alleles have an increased risk to develop AMD. We tested this hypothesis in a cohort of families that manifest both STGD and AMD. With a direct-sequencing mutation detection strategy, we found that AMD-affected relatives of STGD patients are more likely to be carriers of pathogenic STGD alleles than predicted based on chance alone. We further investigated the role of AMD-associated ABCR mutations by testing for expression and ATP-binding defects in an in vitro biochemical assay. We found that mutations associated with AMD have a range of assayable defects ranging from no detectable defect to apparent null alleles. Of the 21 missense ABCR mutations reported in patients with AMD, 16 (76%) show abnormalities in protein expression, ATP-binding or ATPase activity. We infer that carrier relatives of STGD patients are predisposed to develop AMD.

  14. Was the C282Y mutation an Irish Gaelic mutation that the Vikings helped disseminate?

    DEFF Research Database (Denmark)

    Olsson, Karl Sigvard; Konar, Jan; Dufva, Inge Hoegh

    2011-01-01

    The HLA-related hemochromatosis mutation C282Y is thought to have originated in Ireland in a person with HLA-A3-B14 and was spread by Vikings. Irish people with two HLA-A3 alleles had a high risk of hemochromatosis. In this study, from west Sweden, we wanted to test these hypotheses.......The HLA-related hemochromatosis mutation C282Y is thought to have originated in Ireland in a person with HLA-A3-B14 and was spread by Vikings. Irish people with two HLA-A3 alleles had a high risk of hemochromatosis. In this study, from west Sweden, we wanted to test these hypotheses....

  15. Plasminogen alleles influence susceptibility to invasive aspergillosis.

    Directory of Open Access Journals (Sweden)

    Aimee K Zaas

    2008-06-01

    Full Text Available Invasive aspergillosis (IA is a common and life-threatening infection in immunocompromised individuals. A number of environmental and epidemiologic risk factors for developing IA have been identified. However, genetic factors that affect risk for developing IA have not been clearly identified. We report that host genetic differences influence outcome following establishment of pulmonary aspergillosis in an exogenously immune suppressed mouse model. Computational haplotype-based genetic analysis indicated that genetic variation within the biologically plausible positional candidate gene plasminogen (Plg; Gene ID 18855 correlated with murine outcome. There was a single nonsynonymous coding change (Gly110Ser where the minor allele was found in all of the susceptible strains, but not in the resistant strains. A nonsynonymous single nucleotide polymorphism (Asp472Asn was also identified in the human homolog (PLG; Gene ID 5340. An association study within a cohort of 236 allogeneic hematopoietic stem cell transplant (HSCT recipients revealed that alleles at this SNP significantly affected the risk of developing IA after HSCT. Furthermore, we demonstrated that plasminogen directly binds to Aspergillus fumigatus. We propose that genetic variation within the plasminogen pathway influences the pathogenesis of this invasive fungal infection.

  16. Development of allele-specific multiplex PCR to determine the length of poly-T in intron 8 of CFTR

    Directory of Open Access Journals (Sweden)

    Neng Chen

    2014-07-01

    Full Text Available Cystic fibrosis transmembrane conductance regulator (CFTR gene mutation analysis has been implemented for Cystic Fibrosis (CF carrier screening, and molecular diagnosis of CF and congenital bilateral absence of the vas deferens (CBAVD. Although poly-T allele analysis in intron 8 of CFTR is required when a patient is positive for R117H, it is not recommended for routine carrier screening. Therefore, commercial kits for CFTR mutation analysis were designed either to mask the poly-T allele results, unless a patient is R117H positive, or to have the poly-T analysis as a standalone reflex test using the same commercial platform. There are other standalone assays developed to detect poly-T alleles, such as heteroduplex analysis, High Resolution Melting (HRM curve analysis, allele-specific PCR (AS-PCR and Sanger sequencing. In this report, we developed a simple and easy-to-implement multiplex AS-PCR assay using unlabeled standard length primers, which can be used as a reflex or standalone test for CFTR poly-T track analysis. Out of 115 human gDNA samples tested, results from our new AS-PCR matched to the previous known poly-T results or results from Sanger sequencing.

  17. Hitchhiking and Selective Sweeps of Plasmodium falciparum Sulfadoxine and Pyrimethamine Resistance Alleles in a Population from Central Africa▿ †

    Science.gov (United States)

    McCollum, Andrea M.; Basco, Leonardo K.; Tahar, Rachida; Udhayakumar, Venkatachalam; Escalante, Ananias A.

    2008-01-01

    Sulfadoxine-pyrimethamine (SP) resistance in Plasmodium falciparum is encoded by a number of mutations in the dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps) genes. Here, we have characterized point mutations in dhfr and dhps and microsatellite loci around dhfr on chromosome 4 and dhps on chromosome 8 as well as neutral markers on chromosomes 2 and 3 in 332 samples from Yaoundé, Cameroon. The triple mutant dhfr haplotype that originated in Southeast Asia is the most predominant in this sample set, but we also find additional independent haplotypes at low frequency and an incipient process of genetic differentiation among alleles of Southeast Asian origin. As reported for other African populations, we find evidence of a selective sweep for resistant dhfr mutants in this Cameroonian population due to drug selection. Although we find evidence for a selective sweep in dhps mutants associated with SP resistance, the dynamics of dhps mutants appear different than those observed for dhfr mutants. Overall, our results yield support for the use of microsatellite markers to track resistant parasites; however, the detection of resistant dhfr alleles in low frequency, the evidence of divergence among dhfr alleles that share a common evolutionary origin, and the distinct dynamics of resistant dhps alleles emphasize the importance of comprehensive, population-based investigations to evaluate the effects of drug selection on parasite populations. PMID:18765692

  18. Identification and Genetic Diversity of Etambutol Resistant Strains of Mycobacterium Tuberculosis by Allelic-Specific PCR and Spologiotyping

    Directory of Open Access Journals (Sweden)

    Zahra Derakhshani Nezhad

    2012-09-01

    Full Text Available Background & Objectives: Ethambutol is one of the four main drugs in treatment of tuberculosis. The most common mutation associated with this drug resistance usually occurs in codon 306 of embB. The aim of this study was to detect ethambutol resistance using Allele-Specific PCR and Spoligotyping in various subtypes of Mycobacterium tuberculosis.   Methods : 140 sputum specimens were collected from suspected TB patients. They were digested and decontaminated using Pettrof method before culturing them on LJ medium. Drug susceptibility testing was performed on 106 culture positive specimens using proportional method. DNA was extracted from the isolated organisms and subsequently subjected to Allele-Specific PCR to detect any mutationin embB306. Spoligotyping was then used to determine the subtypes.   Results: Out of 106 cultures positive samples, 36 samples (33.9% showed resistance to ethambutol using proportional method. Allele-Specific PCR assay identified 93 as sensitive and 13 (27.6% as resistant strains. The results of PCR were in agreement with result of proportional method. The PCR method revealed that 61.5% of mutation occurred in the first and 38.5% in third nucleotides. Spoligotyping differentiated Mycobacterium tuberculosis strains into Beijing (10 9.4%, Bovis (2 1.8%, CAS (24 22.6%, EAI (1 0.9%, Haarlem (27 25.4%, LAM (5 4.7%, Manu (5 4.7%, T (27 25.4% and U( 2 1,8% families. The high frequency of mutation in embB gene was belonged to Haarlem, CAS and T subfamilies.   Conclusion: Based on results current study, mutations in the genes other than embB might have occurred in the resistant strains that gave negative result in Allele-Specific PCR assay. Therefore other mechanisms of resistance to this antibiotic should be investigated.

  19. Phenylalanine hydroxylase gene mutations in the United States: Report from the maternal PKU collaborative study

    Energy Technology Data Exchange (ETDEWEB)

    Guldberg, P.; Henriksen, K.F.; Guettler, F. [John F. Kennedy Inst., Glostrup (Denmark)] [and others

    1996-07-01

    The major cause of hyperphenylalaninemia is mutations in the gene encoding phenylalanine hydroxylase (PAH). The known mutations have been identified primarily in European patients. The purpose of this study was to determine the spectrum of mutations responsible for PAH deficiency in the United States. One hundred forty-nine patients enrolled in the Maternal PKU Collaborative Study were subjects for clinical and molecular investigations. PAH gene mutations associated with phenylketonuria (PKU) or mild hyperphenylalaninemia (MHP) were identified on 279 of 294 independent mutant chromosomes, a diagnostic efficiency of 95%. The spectrum is composed of 71 different mutations, including 47 missense mutations, 11 splice mutations, 5 nonsense mutations, and 8 microdeletions. Sixteen previously unreported mutations were identified. Among the novel mutations, five were found in patients with MHP, and the remainder were found in patients with PKU. The most common mutations were R408W, IVS12nt1g{r_arrow}a, and Y414C, accounting for 18.7%, 7.8% and 5.4% of the mutant chromosomes, respectively. Thirteen mutations had relative frequencies of 1%-5%, and 55 mutations each had frequencies {le}1%. The mutational spectrum corresponded to that observed for the European ancestry of the U.S. population. To evaluate the extent of allelic variation at the PAH locus within the United States in comparison with other populations, we used allele frequencies to calculate the homozygosity for 11 populations where >90% ascertainment has been obtained. The United States was shown to contain one of the most heterogeneous populations, with homozygosity values similar to Sicily and ethnically mixed sample populations in Europe. The extent of allelic heterogeneity must be a major determining factor in the choice of mutation-detection methodology for molecular diagnosis in PAH deficiency. 47 refs., 1 fig., 5 tabs.

  20. DQB1*06:02 allele-specific expression varies by allelic dosage, not narcolepsy status

    DEFF Research Database (Denmark)

    Weiner Lachmi, Karin; Lin, Ling; Kornum, Birgitte Rahbek

    2012-01-01

    The association of narcolepsy-cataplexy, a sleep disorder caused by the loss of hypocretin/orexin neurons in the hypothalamus, with DQA1*01:02-DQB1*06:02 is one of the tightest known single-allele human leukocyte antigen (HLA) associations. In this study, we explored genome-wide expression...

  1. Genetic improvement of 'NPq' rice with induced mutations

    International Nuclear Information System (INIS)

    Ram, Mahabal

    1974-01-01

    Exposure of the seeds of rice to different doses of gamma-rays increased the total mutation frequency with an increase in the dose rate, and the most economic mutations occurred around 30 kr. Induced mutants with dwarf plant type, early maturity, fine grain, high-yielding ability, and resistance to lodging and major diseases were isolated in the M, and M generations. Genetical studies indicated that height is controlled by 4 pairs of additive genes, grass-clumps by 2 pairs of non-allelic interacting genes (inhibitory), and chlorophyll mutations such as albina by 2 pairs of duplicate genes and xantha by a single gene pair. (author)

  2. The TGFBR1*6A allele is not associated with susceptibility to colorectal cancer in a Spanish population: a case-control study

    International Nuclear Information System (INIS)

    Castillejo, Adela; Guillén-Ponce, Carmen; Carrato, Alfredo; Soto, José-Luís; Mata-Balaguer, Trinidad; Montenegro, Paola; Ochoa, Enrique; Lázaro, Rafael; Martínez-Cantó, Ana; Castillejo, María-Isabel; Guarinos, Carla; Barberá, Víctor-Manuel

    2009-01-01

    TGF-β receptor type I is a mediator of growth inhibitory signals. TGFBR1*6A (rs11466445) is a common polymorphic variant of the TGF-β receptor I gene and has been associated with tumour susceptibility. Nevertheless, the role of this polymorphism as a risk factor for colorectal cancer is controversial. The aim of this study was to assess the association between TGFBR1*6A and colorectal cancer, age, sex, tumour location and tumour stage in a Spanish population. The case-control study involved 800 Spanish subjects: 400 sporadic colorectal cancer patients and 400 age-, sex-, and ethnic-matched controls. The odds ratio (OR) and 95% confidence interval (95% CI) for the TGFBR1*6A polymorphism were calculated using unconditional logistic regression adjusted for age and sex. Analysis of somatic mutations at the GCG repeat of TGFBR1 exon 1 and germline allele-specific expression were also conducted to obtain further information on the contribution of the TGFBR1*6A allele to CRC susceptibility. There was no statistically significant association between the TGFBR1*6A allele and CRC (p > 0.05). The OR was 1.147 (95% CI: 0.799–1.647) for carriers of the TGFBR1*6A allele and 0.878 (95% CI: 0.306–2.520) for homozygous TGFBR1*6A individuals compared with the reference. The frequency of the polymorphism was not affected by age, sex or tumour stage. The TGFBR1*6A allele was more prevalent among colon tumour patients than among rectal tumour patients. Tumour somatic mutations were found in only two of 69 cases (2.9%). Both cases involved a GCG deletion that changed genotype 9A/9A in normal DNA to genotype 9A/8A. Interestingly, these two tumours were positive for microsatellite instability, suggesting that these mutations originated because of a deficient DNA mismatch repair system. Allele-specific expression of the 9A allele was detected in seven of the 14 heterozygous 9A/6A tumour cases. This could have been caused by linkage disequilibrium of the TGFBR1*6A allele with

  3. New mutations in the NHS gene in Nance-Horan Syndrome families from the Netherlands.

    Science.gov (United States)

    Florijn, Ralph J; Loves, Willem; Maillette de Buy Wenniger-Prick, Liesbeth J J M; Mannens, Marcel M A M; Tijmes, Nel; Brooks, Simon P; Hardcastle, Alison J; Bergen, Arthur A B

    2006-09-01

    Mutations in the NHS gene cause Nance-Horan Syndrome (NHS), a rare X-chromosomal recessive disorder with variable features, including congenital cataract, microphthalmia, a peculiar form of the ear and dental anomalies. We investigated the NHS gene in four additional families with NHS from the Netherlands, by dHPLC and direct sequencing. We identified an unique mutation in each family. Three out of these four mutations were not reported before. We report here the first splice site sequence alteration mutation and three protein truncating mutations. Our results suggest that X-linked cataract and NHS are allelic disorders.

  4. JAK and MPL mutations in myeloid malignancies.

    Science.gov (United States)

    Tefferi, Ayalew

    2008-03-01

    The Janus family of non-receptor tyrosine kinases (JAK1, JAK2, JAK3 and tyrosine kinase 2) transduces signals downstream of type I and II cytokine receptors via signal transducers and activators of transcription (STATs). JAK3 is important in lymphoid and JAK2 in myeloid cell proliferation and differentiation. The thrombopoietin receptor MPL is one of several JAK2 cognate receptors and is essential for myelopoiesis in general and megakaryopoiesis in particular. Germline loss-of-function (LOF) JAK3 and MPL mutations cause severe combined immunodeficiency and congenital amegakaryocytic thrombocytopenia, respectively. Germline gain-of-function (GOF) MPL mutation (MPLS505N) causes familial thrombocytosis. Somatic JAK3 (e.g. JAK3A572V, JAK3V722I, JAK3P132T) and fusion JAK2 (e.g. ETV6-JAK2, PCM1-JAK2, BCR-JAK2) mutations have respectively been described in acute megakaryocytic leukemia and acute leukemia/chronic myeloid malignancies. However, current attention is focused on JAK2 (e.g. JAK2V617F, JAK2 exon 12 mutations) and MPL (e.g. MPLW515L/K/S, MPLS505N) mutations associated with myeloproliferative neoplasms (MPNs). A JAK2 mutation, primarily JAK2V617F, is invariably associated with polycythemia vera (PV). The latter mutation also occurs in the majority of patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF). MPL mutational frequency in MPNs is substantially less (<10%). In general, despite a certain degree of genotype - phenotype correlations, the prognostic relevance of harbouring one of these mutations, or their allele burden when present, remains dubious. Regardless, based on the logical assumption that amplified JAK-STAT signalling is central to the pathogenesis of PV, ET and PMF, several anti-JAK2 tyrosine kinase inhibitors have been developed and are currently being tested in humans with these disorders.

  5. High mutation rates limit evolutionary adaptation in Escherichia coli

    Science.gov (United States)

    Wagner, Andreas

    2018-01-01

    Mutation is fundamental to evolution, because it generates the genetic variation on which selection can act. In nature, genetic changes often increase the mutation rate in systems that range from viruses and bacteria to human tumors. Such an increase promotes the accumulation of frequent deleterious or neutral alleles, but it can also increase the chances that a population acquires rare beneficial alleles. Here, we study how up to 100-fold increases in Escherichia coli’s genomic mutation rate affect adaptive evolution. To do so, we evolved multiple replicate populations of asexual E. coli strains engineered to have four different mutation rates for 3000 generations in the laboratory. We measured the ability of evolved populations to grow in their original environment and in more than 90 novel chemical environments. In addition, we subjected the populations to whole genome population sequencing. Although populations with higher mutation rates accumulated greater genetic diversity, this diversity conveyed benefits only for modestly increased mutation rates, where populations adapted faster and also thrived better than their ancestors in some novel environments. In contrast, some populations at the highest mutation rates showed reduced adaptation during evolution, and failed to thrive in all of the 90 alternative environments. In addition, they experienced a dramatic decrease in mutation rate. Our work demonstrates that the mutation rate changes the global balance between deleterious and beneficial mutational effects on fitness. In contrast to most theoretical models, our experiments suggest that this tipping point already occurs at the modest mutation rates that are found in the wild. PMID:29702649

  6. Nitric oxide synthase gene G298 allele

    International Nuclear Information System (INIS)

    Nagib El-Kilany, Galal E.; Nayel, Ehab; Hazzaa, Sahar

    2004-01-01

    Background: Nitric oxide (NO) has an important effect on blood pressure, arterial wall, and the basal release of endothelial NO in hypertension (HPN) may be reduced. Until now, there is no solid data revealing the potential role of the polymorphism of the nitric oxide synthase gene (NOS) in patients with HPN and microvascular angina. Aim: The aim of the present study is to investigate the gene of endothelial nitric oxide synthase (eNOS), as the polymorphism of this gene may be a putative candidate for HPN and initiate the process of atherosclerosis. Methods: Sixty participants were recruited for this study; 50 were hypertensive patients complaining of chest pain [30 of them have electrocardiogram (EKG) changes of ischemia], 20 had isolated HPN, and 10 healthy volunteers served as control. All patients underwent stress myocardial perfusion imaging (MPI) and coronary angiography. Genotyping of eNOS for all patients and controls was performed. The linkages between HPN, microvascular angina and eNOS gene polymorphism were investigated. Results: MPI and coronary angiography revealed that 15 patients had chest pain with true ischemia and reversible myocardial perfusion defects (multiple and mild) but normal epicardial coronary arteries (microvascular angina), while 15 patients had significant coronary artery disease (CAD), and 20 hypertensive patients showed normal perfusion scan and coronary angiography. The prevalence of the NOS G 298 allele was higher in the hypertensive group with microvascular angina (documented by MPI) than it was among the control participants (P<.005). The eNOS allele was significantly higher in the hypertensive group than in the control participants, but there was no significant difference in homozygote mutants among hypertensive participants, x-syndrome and patients with CAD. Conclusion: eNOS gene polymorphism is proved to be an important etiology in microvascular angina (x-syndrome) among hypertensive patients. In addition, the eNOS mutant

  7. GST M1-T1 null allele frequency patterns in geographically assorted human populations: a phylogenetic approach.

    Directory of Open Access Journals (Sweden)

    Senthilkumar Pitchalu Kasthurinaidu

    Full Text Available Genetic diversity in drug metabolism and disposition is mainly considered as the outcome of the inter-individual genetic variation in polymorphism of drug-xenobiotic metabolizing enzyme (XME. Among the XMEs, glutathione-S-transferases (GST gene loci are an important candidate for the investigation of diversity in allele frequency, as the deletion mutations in GST M1 and T1 genotypes are associated with various cancers and genetic disorders of all major Population Affiliations (PAs. Therefore, the present population based phylogenetic study was focused to uncover the frequency distribution pattern in GST M1 and T1 null genotypes among 45 Geographically Assorted Human Populations (GAHPs. The frequency distribution pattern for GST M1 and T1 null alleles have been detected in this study using the data derived from literatures representing 44 populations affiliated to Africa, Asia, Europe, South America and the genome of PA from Gujarat, a region in western India. Allele frequency counting for Gujarat PA and scattered plot analysis for geographical distribution among the PAs were performed in SPSS-21. The GST M1 and GST T1 null allele frequencies patterns of the PAs were computed in Seqboot, Gendist program of Phylip software package (3.69 versions and Unweighted Pair Group method with Arithmetic Mean in Mega-6 software. Allele frequencies from South African Xhosa tribe, East African Zimbabwe, East African Ethiopia, North African Egypt, Caucasian, South Asian Afghanistan and South Indian Andhra Pradesh have been identified as the probable seven patterns among the 45 GAHPs investigated in this study for GST M1-T1 null genotypes. The patternized null allele frequencies demonstrated in this study for the first time addresses the missing link in GST M1-T1 null allele frequencies among GAHPs.

  8. Microsatellite D21D210 (GT-12) allele frequencies in sporadic Alzheimer`s disease

    Energy Technology Data Exchange (ETDEWEB)

    Lannfelt, L; Lilius, L; Viitanen, M; Winblad, B; Basun, H [Huddinge Hospital, Karolinska Institute, Dept. of Geriatric Medicine, (Sweden); Houlden, H; Rossor, M [St. Mary` s Hospital, Dept. of Neurology, Medical School, London (United Kingdom); Hardy, J [University of South Florida, Suncoast Alzheimer` s Disease Research Labs, Department of Psychiatry, Tampa (United States)

    1995-02-01

    Four disease-causing mutations have so far been described in the amyloid precursor protein gene on chromosome 21 in familial early-onset Alzheimer`s disease. Linkage analysis with a fourteen-allele microsatellite at D21S210 named GT-12 has proven useful in the elucidation of amyloid presursor protein gene involvement in Alzheimer`s disease families, as it is closely linked to the gene. Most cases of Alzheimer`s disease are thought to be sporadic and not familial. However, evidence from earlier studies suggests an important genetic contribution also in sporadic cases, where gene-environment interaction may contribute to the disease. We have determined frequencies of the GT-12 alleles in 78 Swedish and 49 British sporadic Alzheimer`s disease cases and 104 healthy elderly control subjects, to investigate if the disease associates with a particular genotype in GT-12. However, no differences in allele frequencies were observed between any of the groups. (au) (26 refs.).

  9. Parkinson’s disease and low frequency alleles found together throughout LRRK2

    Science.gov (United States)

    Paisán-Ruiz, Coro; Washecka, Nicole; Nath, Priti; Singleton, Andrew B.; Corder, Elizabeth H.

    2016-01-01

    Mutations within LRRK2, most notably p.G2019S, cause Parkinson’s disease (PD) in rare monogenic families, and sporadic occurrences in diverse populations. We investigated variation throughout LRRK2 (84 SNPs; genotype or diplotype found for 49 LD blocks) for 275 cases (European ancestry, onset at age 60 or older) and 275 neurologically healthy control subjects (NINDS Neurogenetics Repository). Three grade-of-membership groups, i.e. genetic risk sets, were identified that exactly matched many subjects (cases: 46, 4, 137; controls: 0, 178, 0), and distinguished 94% of the subjects (i.e. > 50% likeness to one set). Set I, affected, carried certain low frequency alleles located in multiple functional domains. Set II was unaffected. Set III, also affected, resembled II except for slightly elevated frequencies of minor alleles not defining set I. We conclude that certain low frequency alleles distributed throughout LRRK2 are a genetic background to a third of cases, defining a distinct subset. PMID:19489756

  10. X-linked cataract and Nance-Horan syndrome are allelic disorders.

    Science.gov (United States)

    Coccia, Margherita; Brooks, Simon P; Webb, Tom R; Christodoulou, Katja; Wozniak, Izabella O; Murday, Victoria; Balicki, Martha; Yee, Harris A; Wangensteen, Teresia; Riise, Ruth; Saggar, Anand K; Park, Soo-Mi; Kanuga, Naheed; Francis, Peter J; Maher, Eamonn R; Moore, Anthony T; Russell-Eggitt, Isabelle M; Hardcastle, Alison J

    2009-07-15

    Nance-Horan syndrome (NHS) is an X-linked developmental disorder characterized by congenital cataract, dental anomalies, facial dysmorphism and, in some cases, mental retardation. Protein truncation mutations in a novel gene (NHS) have been identified in patients with this syndrome. We previously mapped X-linked congenital cataract (CXN) in one family to an interval on chromosome Xp22.13 which encompasses the NHS locus; however, no mutations were identified in the NHS gene. In this study, we show that NHS and X-linked cataract are allelic diseases. Two CXN families, which were negative for mutations in the NHS gene, were further analysed using array comparative genomic hybridization. CXN was found to be caused by novel copy number variations: a complex duplication-triplication re-arrangement and an intragenic deletion, predicted to result in altered transcriptional regulation of the NHS gene. Furthermore, we also describe the clinical and molecular analysis of seven families diagnosed with NHS, identifying four novel protein truncation mutations and a novel large deletion encompassing the majority of the NHS gene, all leading to no functional protein. We therefore show that different mechanisms, aberrant transcription of the NHS gene or no functional NHS protein, lead to different diseases. Our data highlight the importance of copy number variation and non-recurrent re-arrangements leading to different severity of disease and describe the potential mechanisms involved.

  11. Allelic variation of the FRMD7 gene in congenital idiopathic nystagmus.

    Science.gov (United States)

    Self, James E; Shawkat, Fatima; Malpas, Crispin T; Thomas, N Simon; Harris, Christopher M; Hodgkins, Peter R; Chen, Xiaoli; Trump, Dorothy; Lotery, Andrew J

    2007-09-01

    To perform a genotype-phenotype correlation study in an X-linked congenital idiopathic nystagmus pedigree (pedigree 1) and to assess the allelic variance of the FRMD7 gene in congenital idiopathic nystagmus. Subjects from pedigree 1 underwent detailed clinical examination including nystagmology. Screening of FRMD7 was undertaken in pedigree 1 and in 37 other congenital idiopathic nystagmus probands and controls. Direct sequencing confirmed sequence changes. X-inactivation studies were performed in pedigree 1. The nystagmus phenotype was extremely variable in pedigree 1. We identified 2 FRMD7 mutations. However, 80% of X-linked families and 96% of simplex cases showed no mutations. X-inactivation studies demonstrated no clear causal link between skewing and variable penetrance. We confirm profound phenotypic variation in X-linked congenital idiopathic nystagmus pedigrees. We demonstrate that other congenital nystagmus genes exist besides FRMD7. We show that the role of X inactivation in variable penetrance is unclear in congenital idiopathic nystagmus. Clinical Relevance We demonstrate that phenotypic variation of nystagmus occurs in families with FRMD7 mutations. While FRMD7 mutations may be found in some cases of X-linked congenital idiopathic nystagmus, the diagnostic yield is low. X-inactivation assays are unhelpful as a test for carrier status for this disease.

  12. Hereditary cancer genes are highly susceptible to splicing mutations

    Science.gov (United States)

    Soemedi, Rachel; Maguire, Samantha; Murray, Michael F.; Monaghan, Sean F.

    2018-01-01

    Substitutions that disrupt pre-mRNA splicing are a common cause of genetic disease. On average, 13.4% of all hereditary disease alleles are classified as splicing mutations mapping to the canonical 5′ and 3′ splice sites. However, splicing mutations present in exons and deeper intronic positions are vastly underreported. A recent re-analysis of coding mutations in exon 10 of the Lynch Syndrome gene, MLH1, revealed an extremely high rate (77%) of mutations that lead to defective splicing. This finding is confirmed by extending the sampling to five other exons in the MLH1 gene. Further analysis suggests a more general phenomenon of defective splicing driving Lynch Syndrome. Of the 36 mutations tested, 11 disrupted splicing. Furthermore, analyzing past reports suggest that MLH1 mutations in canonical splice sites also occupy a much higher fraction (36%) of total mutations than expected. When performing a comprehensive analysis of splicing mutations in human disease genes, we found that three main causal genes of Lynch Syndrome, MLH1, MSH2, and PMS2, belonged to a class of 86 disease genes which are enriched for splicing mutations. Other cancer genes were also enriched in the 86 susceptible genes. The enrichment of splicing mutations in hereditary cancers strongly argues for additional priority in interpreting clinical sequencing data in relation to cancer and splicing. PMID:29505604

  13. Hereditary cancer genes are highly susceptible to splicing mutations.

    Directory of Open Access Journals (Sweden)

    Christy L Rhine

    2018-03-01

    Full Text Available Substitutions that disrupt pre-mRNA splicing are a common cause of genetic disease. On average, 13.4% of all hereditary disease alleles are classified as splicing mutations mapping to the canonical 5' and 3' splice sites. However, splicing mutations present in exons and deeper intronic positions are vastly underreported. A recent re-analysis of coding mutations in exon 10 of the Lynch Syndrome gene, MLH1, revealed an extremely high rate (77% of mutations that lead to defective splicing. This finding is confirmed by extending the sampling to five other exons in the MLH1 gene. Further analysis suggests a more general phenomenon of defective splicing driving Lynch Syndrome. Of the 36 mutations tested, 11 disrupted splicing. Furthermore, analyzing past reports suggest that MLH1 mutations in canonical splice sites also occupy a much higher fraction (36% of total mutations than expected. When performing a comprehensive analysis of splicing mutations in human disease genes, we found that three main causal genes of Lynch Syndrome, MLH1, MSH2, and PMS2, belonged to a class of 86 disease genes which are enriched for splicing mutations. Other cancer genes were also enriched in the 86 susceptible genes. The enrichment of splicing mutations in hereditary cancers strongly argues for additional priority in interpreting clinical sequencing data in relation to cancer and splicing.

  14. Phenylketonuria mutation analysis in Northern Ireland: A rapid stepwise approach

    Energy Technology Data Exchange (ETDEWEB)

    Zschocke, J.; Graham, C.A.; Nevin, N.C. [Queen`s Univ., Belfast (Australia)] [and others

    1995-12-01

    We present a multistep approach for the rapid analysis of phenylketonuria (PKU) mutations. In the first step, three common mutations and a polymorphic short tandem repeat (STR) system are rapidly analyzed with a fluorescent multiplex assay. In the second step, minihaplotypes combining STR and VNTR data are used to determine rare mutations likely to be present in an investigated patient, which are then confirmed by restriction enzyme analysis. The remaining mutations are analyzed with denaturant gradient-gel electrophoresis and sequencing. The first two steps together identify both mutations in 90%-95% of PKU patients, and results can be obtained within 2 d. We have investigated 121 Northern Irish families with hyperphenylalaninemia, including virtually all patients born since 1972, and have found 34 different mutations on 241 of the 242 mutant alleles. Three mutations (R408W, 165T, and F39L) account for 57.5% of mutations, while 14 mutations occur with a frequency of 1%-6%. The present analysis system is efficient and inexpensive and is particularly well suited to routine mutation analysis in a diagnostic setting. 19 refs., 5 tabs.

  15. Allele Frequency - JSNP | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available nd 39 SNPs are assayed in three (POP_*) and two (RIKEN_japanese_*) panels, respectively. Derived from Flat f... assay (JBIC-allele and RIKEN_japanese_*), TaqMan assay (RIKEN-allele) or direct sequencing / allelic discri...unteers under informed consent RIKEN_japanese_normal_weight - 711 unrelated japanese normal weight volunteer...s ( body mass index RIKEN_japanese_obese - 796 unrelated japanese obese patients

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

    Science.gov (United States)

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

    2015-06-01

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

  17. Impact of population structure, effective bottleneck time, and allele frequency on linkage disequilibrium maps.

    Science.gov (United States)

    Zhang, Weihua; Collins, Andrew; Gibson, Jane; Tapper, William J; Hunt, Sarah; Deloukas, Panos; Bentley, David R; Morton, Newton E

    2004-12-28

    Genetic maps in linkage disequilibrium (LD) units play the same role for association mapping as maps in centimorgans provide at much lower resolution for linkage mapping. Association mapping of genes determining disease susceptibility and other phenotypes is based on the theory of LD, here applied to relations with three phenomena. To test the theory, markers at high density along a 10-Mb continuous segment of chromosome 20q were studied in African-American, Asian, and Caucasian samples. Population structure, whether created by pooling samples from divergent populations or by the mating pattern in a mixed population, is accurately bioassayed from genotype frequencies. The effective bottleneck time for Eurasians is substantially less than for migration out of Africa, reflecting later bottlenecks. The classical dependence of allele frequency on mutation age does not hold for the generally shorter time span of inbreeding and LD. Limitation of the classical theory to mutation age justifies the assumption of constant time in a LD map, except for alleles that were rare at the effective bottleneck time or have arisen since. This assumption is derived from the Malecot model and verified in all samples. Tested measures of relative efficiency, support intervals, and localization error determine the operating characteristics of LD maps that are applicable to every sexually reproducing species, with implications for association mapping, high-resolution linkage maps, evolutionary inference, and identification of recombinogenic sequences.

  18. Database for the ampC alleles in Acinetobacter baumannii.

    Directory of Open Access Journals (Sweden)

    Nabil Karah

    Full Text Available Acinetobacter baumannii is a troublesome opportunistic pathogen with a high capacity for clonal dissemination. We announce the establishment of a database for the ampC locus in A. baumannii, in which novel ampC alleles are differentiated based on the occurrence of ≥ 1 nucleotide change, regardless of whether it is silent or missense. The database is openly accessible at the pubmlst platform for A. baumannii (http://pubmlst.org/abaumannii/. Forty-eight distinctive alleles of the ampC locus have so far been identified and deposited in the database. Isolates from clonal complex 1 (CC1, according to the Pasteur multilocus sequence typing scheme, had a variety of the ampC locus alleles, including alleles 1, 3, 4, 5, 6, 7, 8, 13, 14, 17, and 18. On the other hand, isolates from CC2 had the ampC alleles 2, 3, 19, 20, 21, 22, 23, 24, 26, 27, 28, and 46. Allele 3 was characteristic for sequence types ST3 or ST32. The ampC alleles 10, 16, and 25 were characteristic for CC10, ST16, and CC25, respectively. Our study points out that novel gene databases, in which alleles are numbered based on differences in their nucleotide identities, should replace traditional records that use amino acid substitutions to define new alleles.

  19. Impact of Fluoroquinolone Resistance Mutations on Gonococcal Fitness and In Vivo Selection for Compensatory Mutations

    Science.gov (United States)

    Kunz, Anjali N.; Begum, Afrin A.; Wu, Hong; D'Ambrozio, Jonathan A.; Robinson, James M.; Shafer, William M.; Bash, Margaret C.; Jerse, Ann E.

    2012-01-01

    Background. Quinolone-resistant Neisseria gonorrhoeae (QRNG) arise from mutations in gyrA (intermediate resistance) or gyrA and parC (resistance). Here we tested the consequence of commonly isolated gyrA91/95 and parC86 mutations on gonococcal fitness. Methods. Mutant gyrA91/95 and parC86 alleles were introduced into wild-type gonococci or an isogenic mutant that is resistant to macrolides due to an mtrR−79 mutation. Wild-type and mutant bacteria were compared for growth in vitro and in competitive murine infection. Results. In vitro growth was reduced with increasing numbers of mutations. Interestingly, the gyrA91/95 mutation conferred an in vivo fitness benefit to wild-type and mtrR−79 mutant gonococci. The gyrA91/95, parC86 mutant, in contrast, showed a slight fitness defect in vivo, and the gyrA91/95, parC86, mtrR−79 mutant was markedly less fit relative to the parent strains. A ciprofloxacin-resistant (CipR) mutant was selected during infection with the gyrA91/95, parC86, mtrR−79 mutant in which the mtrR−79 mutation was repaired and the gyrA91 mutation was altered. This in vivo–selected mutant grew as well as the wild-type strain in vitro. Conclusions. gyrA91/95 mutations may contribute to the spread of QRNG. Further acquisition of a parC86 mutation abrogates this fitness advantage; however, compensatory mutations can occur that restore in vivo fitness and maintain CipR. PMID:22492860

  20. Elevated mutation rate during meiosis in Saccharomyces cerevisiae.

    Science.gov (United States)

    Rattray, Alison; Santoyo, Gustavo; Shafer, Brenda; Strathern, Jeffrey N

    2015-01-01

    Mutations accumulate during all stages of growth, but only germ line mutations contribute to evolution. While meiosis contributes to evolution by reassortment of parental alleles, we show here that the process itself is inherently mutagenic. We have previously shown that the DNA synthesis associated with repair of a double-strand break is about 1000-fold less accurate than S-phase synthesis. Since the process of meiosis involves many programmed DSBs, we reasoned that this repair might also be mutagenic. Indeed, in the early 1960's Magni and Von Borstel observed elevated reversion of recessive alleles during meiosis, and found that the revertants were more likely to be associated with a crossover than non-revertants, a process that they called "the meiotic effect." Here we use a forward mutation reporter (CAN1 HIS3) placed at either a meiotic recombination coldspot or hotspot near the MAT locus on Chromosome III. We find that the increased mutation rate at CAN1 (6 to 21 -fold) correlates with the underlying recombination rate at the locus. Importantly, we show that the elevated mutation rate is fully dependent upon Spo11, the protein that introduces the meiosis specific DSBs. To examine associated recombination we selected for random spores with or without a mutation in CAN1. We find that the mutations isolated this way show an increased association with recombination (crossovers, loss of crossover interference and/or increased gene conversion tracts). Polζ appears to contribute about half of the mutations induced during meiosis, but is not the only source of mutations for the meiotic effect. We see no difference in either the spectrum or distribution of mutations between mitosis and meiosis. The correlation of hotspots with elevated mutagenesis provides a mechanism for organisms to control evolution rates in a gene specific manner.

  1. HFE gene mutations in coronary atherothrombotic disease

    Directory of Open Access Journals (Sweden)

    Calado R.T.

    2000-01-01

    Full Text Available Although iron can catalyze the production of free radicals involved in LDL lipid peroxidation, the contribution of iron overload to atherosclerosis remains controversial. The description of two mutations in the HFE gene (Cys282Tyr and His63Asp related to hereditary hemochromatosis provides an opportunity to address the question of the association between iron overload and atherosclerosis. We investigated the prevalence of HFE mutations in 160 survivors of myocardial infarction with angiographically demonstrated severe coronary atherosclerotic disease, and in 160 age-, gender- and race-matched healthy control subjects. PCR amplification of genomic DNA followed by RsaI and BclI restriction enzyme digestion was used to determine the genotypes. The frequency of the mutant Cys282Tyr allele was identical among patients and controls (0.022; carrier frequency, 4.4%, whereas the mutant His63Asp allele had a frequency of 0.143 (carrier frequency, 27.5% in controls and of 0.134 (carrier frequency, 24.5% in patients. Compound heterozygotes were found in 2 of 160 (1.2% controls and in 1 of 160 (0.6% patients. The finding of a similar prevalence of Cys282Tyr and His63Asp mutations in the HFE gene among controls and patients with coronary atherothrombotic disease, indirectly questions the possibility of an association between hereditary hemochromatosis and atherosclerosis.

  2. Occurrence, distribution and phenotype of arylsulfatase A mutations in patients with metachromatic leukodystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Berger, J.; Loeschl, B.; Bernheimer, H. [Universitaet Wien (Austria)] [and others

    1997-03-31

    Occurrence, distribution, and phenotype of arylsulfatase A (ASA) mutations were investigated in 27 patients with metachromatic leukodystrophy (MLD) from Central Europe, mainly from Austria (n = 15) and Poland (n = 9). Genomic DNA from leukocytes, fibroblasts, or paraffin-embedded, formalin-fixed brain or nerve tissue, respectively, was tested by natural or mutated primer-modulated PCR restriction fragment length polymorphism for the eight most common European mutations: R84Q, S96F, 459+1G>A, I179S, A212V, 1204+1G>A, P426L, and 1401del11bp. The overall identification rate of unrelated MLD alleles was the highest in adult (90%), medium in juvenile (50%), and lowest in late infantile (36%) MLD patients. The two common alleles, 459+1G>A and P426L, together accounted for 42% of all 50 unrelated MLD alleles investigated; I179S was observed in 6 of 50 MLD alleles (12%). Thus, I179S was far more frequent than hitherto thought and appears to be a third common mutation in Europe. Moreover, a different allelic distribution between Austrian and Polish juvenile patients was disclosed, indicating genetic heterogeneity of MLD even within Central Europe. The genotype-phenotype correlation suggested by Polten et al. was not followed by all of our MLD patients. Moreover, some MLD patients with identical ASA mutations presented with different phenotypes. This may be due, at least in some cases, to the presence of an additional mutation on individual mutant alleles. Therefore, prediction of the clinical course from single mutation analysis is not possible. 28 refs.

  3. AllelicImbalance: An R/ bioconductor package for detecting, managing, and visualizing allele expression imbalance data from RNA sequencing

    DEFF Research Database (Denmark)

    Gådin, Jesper R.; van't Hooft, Ferdinand M.; Eriksson, Per

    2015-01-01

    the possible biases. Results: We present AllelicImblance, a software program that is designed to detect, manage, and visualize allelic imbalances comprehensively. The purpose of this software is to allow users to pose genetic questions in any RNA sequencing experiment quickly, enhancing the general utility...... of RNA sequencing. The visualization features can reveal notable, non-trivial allelic imbalance behavior over specific regions, such as exons. Conclusions: The software provides a complete framework to perform allelic imbalance analyses of aligned RNA sequencing data, from detection to visualization...

  4. Efficient simulation and likelihood methods for non-neutral multi-allele models.

    Science.gov (United States)

    Joyce, Paul; Genz, Alan; Buzbas, Erkan Ozge

    2012-06-01

    Throughout the 1980s, Simon Tavaré made numerous significant contributions to population genetics theory. As genetic data, in particular DNA sequence, became more readily available, a need to connect population-genetic models to data became the central issue. The seminal work of Griffiths and Tavaré (1994a , 1994b , 1994c) was among the first to develop a likelihood method to estimate the population-genetic parameters using full DNA sequences. Now, we are in the genomics era where methods need to scale-up to handle massive data sets, and Tavaré has led the way to new approaches. However, performing statistical inference under non-neutral models has proved elusive. In tribute to Simon Tavaré, we present an article in spirit of his work that provides a computationally tractable method for simulating and analyzing data under a class of non-neutral population-genetic models. Computational methods for approximating likelihood functions and generating samples under a class of allele-frequency based non-neutral parent-independent mutation models were proposed by Donnelly, Nordborg, and Joyce (DNJ) (Donnelly et al., 2001). DNJ (2001) simulated samples of allele frequencies from non-neutral models using neutral models as auxiliary distribution in a rejection algorithm. However, patterns of allele frequencies produced by neutral models are dissimilar to patterns of allele frequencies produced by non-neutral models, making the rejection method inefficient. For example, in some cases the methods in DNJ (2001) require 10(9) rejections before a sample from the non-neutral model is accepted. Our method simulates samples directly from the distribution of non-neutral models, making simulation methods a practical tool to study the behavior of the likelihood and to perform inference on the strength of selection.

  5. Multimer Formation Explains Allelic Suppression of PRDM9 Recombination Hotspots.

    Science.gov (United States)

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

    2015-09-01

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

  6. MPL515 mutations in myeloproliferative and other myeloid disorders: a study of 1182 patients.

    Science.gov (United States)

    Pardanani, Animesh D; Levine, Ross L; Lasho, Terra; Pikman, Yana; Mesa, Ruben A; Wadleigh, Martha; Steensma, David P; Elliott, Michelle A; Wolanskyj, Alexandra P; Hogan, William J; McClure, Rebecca F; Litzow, Mark R; Gilliland, D Gary; Tefferi, Ayalew

    2006-11-15

    Recently, a gain-of-function MPL mutation, MPLW515L, was described in patients with JAK2V617F-negative myelofibrosis with myeloid metaplasia (MMM). To gain more information on mutational frequency, disease specificity, and clinical correlates, genomic DNA from 1182 patients with myeloproliferative and other myeloid disorders and 64 healthy controls was screened for MPL515 mutations, regardless of JAK2V617F mutational status: 290 with MMM, 242 with polycythemia vera, 318 with essential thrombocythemia (ET), 88 with myelodysplastic syndrome, 118 with chronic myelomonocytic leukemia, and 126 with acute myeloid leukemia (AML). MPL515 mutations, either MPLW515L (n = 17) or a previously undescribed MPLW515K (n = 5), were detected in 20 patients. The diagnosis of patients with mutant MPL alleles at the time of molecular testing was de novo MMM in 12 patients, ET in 4, post-ET MMM in 1, and MMM in blast crisis in 3. Six patients carried the MPLW515L and JAK2V617F alleles concurrently. We conclude that MPLW515L or MPLW515K mutations are present in patients with MMM or ET at a frequency of approximately 5% and 1%, respectively, but are not observed in patients with polycythemia vera (PV) or other myeloid disorders. Furthermore, MPL mutations may occur concurrently with the JAK2V617F mutation, suggesting that these alleles may have functional complementation in myeloproliferative disease.

  7. Study of Four Common Mutations of Familial Mediterranean Fever in North-West of Iran

    Directory of Open Access Journals (Sweden)

    Abbas Karimi

    2012-09-01

    Full Text Available Background and Objectives : Familial Mediterranean Fever, an autosomal recessive disorder, is the most common and well known periodical fevers syndrome. Disease is mainly prevalent among non-Ashkenazi Jews, Arabs, Turks and Armenia. According to the geographical location of North-West of Iran, neighboring with two high risk FMF population (Turkey and Armenia, the prevalence of FMF in this region of Iran is not unlikely. The aim of this study was to estimate the carriers rate of FMF common mutations in healthy control people. Results can be potentially useful to estimate prevalence of disease.   Methods : Randomly 200 samples from healthy people [non-FMF] from North-West of Iran selected. After taking consent, DNA was extracted from blood samples of these groups. Then mutations were evaluated using ARMS-PCR and RFLP-PCR techniques.   Results : from 400 studied alleles, 44 and 7 mutant alleles were found for E148Q and V726A respectively. For 2 other mutations, no mutant alleles were found. The total allelic frequency for these four common mutations was 0.132. The carriers rate was 23.4%.   Conclusion : This study showed that E148Q has high mutation frequency relative to other mutations in North-West of Iran.

  8. Complementation pattern of lexB and recA mutations in Escherichia coli K12; mapping of tif-1, lexB and recA mutations

    International Nuclear Information System (INIS)

    Morand, P.; Goze, A.; Devoret, R.

    1977-01-01

    Three lexB mutations, whose phenotypes have been previously characterized, are studied here in relation to a few recA mutations as to their complementation pattern and relative location. The restoration of resistance to UV-light and to X-rays in the hetero-allelic diploid bacteria was used as a test for dominance and complementation. The wild type allele was always dominant over the mutant allele. Only partial complementation was found between lexB and two rexA alleles. There was no complementation between the recA alleles. All the data taken together strongly suggest that the complementations found are intragenic: lexB and recA mutations are in one gene. Mapping of lexB, recA and tif-1 mutations in relation to srl-1 and cysC by phage P1 transduction shows that lexB and the tif-1 mutations form a cluster proximal to srl-1 whereas recA mutations are located at the other extremity of the gene. Variability with temperature of cotransduction frequencies as well as their extended range of values prevent a meaningful calculation of the length of the recA gene. Our hypothesis is that the recA protein has two functional regions called A and B respectively defined at the genetical level by recA and lexB mutations and that it is, in vivo, an oligomeric protein forming a complex with the lexA protein. This complex is postulated to be multifunctional: recombination and control of exonuclease V are effected by the A region while the B region and lexA protein effect induced DNA repair and lysogenic induction. (orig.) [de

  9. Estimating and testing the effect of allelic recombination on the ...

    African Journals Online (AJOL)

    Jane

    2011-01-21

    Jan 21, 2011 ... The significance of the correlation coefficient as well as the fitted regression model was obtained using. Analysis of Variance method. Key words: Allele, genotype, regression, correlation, F-ratio, analysis of variance. INTRODUCTION .... while if the allelic replacement is being made on an Aa individual the ...

  10. Low Penetrance Alleles in Colorectal Cancer: the arachidonic acid pathway

    NARCIS (Netherlands)

    C.L.E. Siezen

    2006-01-01

    textabstractIn summary, we can conclude that we have successfully identified low penetrance alleles in the PPAR., PLA2G2A and ALOX15 genes, conferring differential colorectal adenoma risk, and two such alleles in the PTGS2 gene, one of which is also involved in colorectal cancer risk. These

  11. Comparison of bovine lymphocyte antigen DRB3.2 allele ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-08-04

    Aug 4, 2008 ... The bovine lymphocyte antigen (BoLA-DRB3) gene encodes cell ... alleles were more resistant to clinical mastitis. ... DRB3.2 allele pattern in two Iranian Holstein cow .... observed and the number of immune parameters with.

  12. Evolutionary dynamics of sporophytic self-incompatibility alleles in plants

    DEFF Research Database (Denmark)

    Schierup, Mikkel Heide; Vekemans, Xavier; Christiansen, Freddy Bugge

    1997-01-01

    codominantly in both pollen and style (SSIcod), in the second, alleles form a dominance hierarchy in pollen and style (SSIdom). In the third model, alleles interact codominantly in the style and form a dominance hierarchy in the pollen (SSIdomcod). The SSIcod model behaves similarly to the model...

  13. Human minisatellite alleles detectable only after PCR amplification.

    Science.gov (United States)

    Armour, J A; Crosier, M; Jeffreys, A J

    1992-01-01

    We present evidence that a proportion of alleles at two human minisatellite loci is undetected by standard Southern blot hybridization. In each case the missing allele(s) can be identified after PCR amplification and correspond to tandem arrays too short to detect by hybridization. At one locus, there is only one undetected allele (population frequency 0.3), which contains just three repeat units. At the second locus, there are at least five undetected alleles (total population frequency 0.9) containing 60-120 repeats; they are not detected because these tandem repeats give very poor signals when used as a probe in standard Southern blot hybridization, and also cross-hybridize with other sequences in the genome. Under these circumstances only signals from the longest tandemly repeated alleles are detectable above the nonspecific background. The structures of these loci have been compared in human and primate DNA, and at one locus the short human allele containing three repeat units is shown to be an intermediate state in the expansion of a monomeric precursor allele in primates to high copy number in the longer human arrays. We discuss the implications of such loci for studies of human populations, minisatellite isolation by cloning, and the evolution of highly variable tandem arrays.

  14. Comparative frequency and allelic distribution of ABO and Rh (D ...

    African Journals Online (AJOL)

    Background: Allelic distribution of major blood groups (ABO and rhesus) has not been defined in Bangladeshi population. Determinants of blood group frequency in this region have not been studied properly. Aim: To determine ABO and rhesus blood group frequency and allelic distribution in a multiethnic area of ...

  15. Apolipoprotein E4 allele does not influence serum triglyceride ...

    African Journals Online (AJOL)

    This study investigated how the APOε4 allele affects the serum triglyceride response after a fatmeal in apparently healthy black South African young adults. Sixty students were successfully screened for APOE genotype using Restriction Fragment Length Polymorphism (RFLP) and were divided into four groups; the ε2 allele ...

  16. Mutations in the codon for a conserved arginine-1563 in the COL4A5 collagen gene in Alport syndrome

    DEFF Research Database (Denmark)

    Zhou, J; Gregory, M C; Hertz, Jens Michael

    1993-01-01

    for arginine to the translation stop codon TGA. In Utah kindred 2123 and in the Danish kindred A13, there was a C-->T mutation in the noncoding strand changing the same codon to CAA for glutamine. Both mutations were confirmed by allele-specific hybridization on PCR-amplified DNA from other family members....

  17. Natural selection against a circadian clock gene mutation in mice.

    Science.gov (United States)

    Spoelstra, Kamiel; Wikelski, Martin; Daan, Serge; Loudon, Andrew S I; Hau, Michaela

    2016-01-19

    Circadian rhythms with an endogenous period close to or equal to the natural light-dark cycle are considered evolutionarily adaptive ("circadian resonance hypothesis"). Despite remarkable insight into the molecular mechanisms driving circadian cycles, this hypothesis has not been tested under natural conditions for any eukaryotic organism. We tested this hypothesis in mice bearing a short-period mutation in the enzyme casein kinase 1ε (tau mutation), which accelerates free-running circadian cycles. We compared daily activity (feeding) rhythms, survivorship, and reproduction in six replicate populations in outdoor experimental enclosures, established with wild-type, heterozygous, and homozygous mice in a Mendelian ratio. In the release cohort, survival was reduced in the homozygote mutant mice, revealing strong selection against short-period genotypes. Over the course of 14 mo, the relative frequency of the tau allele dropped from initial parity to 20%. Adult survival and recruitment of juveniles into the population contributed approximately equally to the selection for wild-type alleles. The expression of activity during daytime varied throughout the experiment and was significantly increased by the tau mutation. The strong selection against the short-period tau allele observed here contrasts with earlier studies showing absence of selection against a Period 2 (Per2) mutation, which disrupts internal clock function, but does not change period length. These findings are consistent with, and predicted by the theory that resonance of the circadian system plays an important role in individual fitness.

  18. Non-recessive Bt toxin resistance conferred by an intracellular cadherin mutation in field-selected populations of cotton bollworm.

    Directory of Open Access Journals (Sweden)

    Haonan Zhang

    Full Text Available Transgenic crops producing Bacillus thuringiensis (Bt toxins have been planted widely to control insect pests, yet evolution of resistance by the pests can reduce the benefits of this approach. Recessive mutations in the extracellular domain of toxin-binding cadherin proteins that confer resistance to Bt toxin Cry1Ac by disrupting toxin binding have been reported previously in three major lepidopteran pests, including the cotton bollworm, Helicoverpa armigera. Here we report a novel allele from cotton bollworm with a deletion in the intracellular domain of cadherin that is genetically linked with non-recessive resistance to Cry1Ac. We discovered this allele in each of three field-selected populations we screened from northern China where Bt cotton producing Cry1Ac has been grown intensively. We expressed four types of cadherin alleles in heterologous cell cultures: susceptible, resistant with the intracellular domain mutation, and two complementary chimeric alleles with and without the mutation. Cells transfected with each of the four cadherin alleles bound Cry1Ac and were killed by Cry1Ac. However, relative to cells transfected with either the susceptible allele or the chimeric allele lacking the intracellular domain mutation, cells transfected with the resistant allele or the chimeric allele containing the intracellular domain mutation were less susceptible to Cry1Ac. These results suggest that the intracellular domain of cadherin is involved in post-binding events that affect toxicity of Cry1Ac. This evidence is consistent with the vital role of the intracellular region of cadherin proposed by the cell signaling model of the mode of action of Bt toxins. Considered together with previously reported data, the results suggest that both pore formation and cell signaling pathways contribute to the efficacy of Bt toxins.

  19. Pitfalls in genetic testing: a case of a SNP in primer-annealing region leading to allele dropout in BRCA1.

    Science.gov (United States)

    Silva, Felipe Carneiro; Torrezan, Giovana Tardin; Brianese, Rafael Canfield; Stabellini, Raquel; Carraro, Dirce Maria

    2017-07-01

    Hereditary breast and ovarian cancer is characterized by mutations in BRCA1 or BRCA2 genes and PCR-based screening techniques, such as capillary sequencing and next-generation sequencing (NGS), are considered gold standard methods for detection of pathogenic mutations in these genes. Single-nucleotide polymorphisms (SNPs) constitute a vast source of variation in the human genome and represent a risk for misdiagnosis in genetic testing, since the presence of a SNP in primer-annealing sites may cause false negative results due to allele dropout. However, few reports are available and the frequency of this phenomenon in diagnostic assays remains unknown. In this article, we investigated the causes of a false negative capillary sequencing result in BRCA1 involving a mother-daughter dyad. Using several molecular strategies, including different DNA polymerases, primer redesign, allele-specific PCR and NGS, we established that the initial misdiagnosis was caused by a SNP located in the primer-annealing region, leading to allele dropout of the mutated allele. Assuming that this problem can also occur in any PCR-based method that are widely used in diagnostic settings, the clinical report presented here draws attention for one of the limitations of genetic testing in general, for which medical and laboratory communities need to be aware.

  20. Ancient DNA Investigation of a Medieval German Cemetery Confirms Long-Term Stability of CCR5-Δ32 Allele Frequencies in Central Europe.

    Science.gov (United States)

    Bouwman, Abigail; Shved, Natallia; Akgül, Gülfirde; Rühli, Frank; Warinner, Christina

    2017-04-01

    The CCR5-Δ32 mutation present in European populations is among the most prominently debated cases of recent positive selection in humans. This allele, a 32-bp deletion that renders the T-cell CCR5 receptor nonfunctional, has important epidemiological and public health significance, as homozygous carriers are resistant to several HIV strains. However, although the function of this allele in preventing HIV infection is now well described, its human evolutionary origin is poorly understood. Initial attempts to determine the emergence of the CCR5-Δ32 allele pointed to selection during the 14th-century Black Death pandemic; however, subsequent analyses suggest that the allele rose in frequency more than 5,000 years ago, possibly through drift. Recently, three studies have identified populations predating the 14th century CE that are positive for the CCR5-Δ32 allele, supporting the claim for a more ancient origin. However, these studies also suggest poorly understood regional differences in the recent evolutionary history of the CCR5-Δ32 allele. Here a new hydrolysis-probe-based real-time PCR assay was designed to ascertain CCR5 allele frequency in 53 individuals from a 10th- to 12th-century CE church and convent complex in central Germany that predates outbreaks of the Black Death pandemic. High-confidence genotypes were obtained for 32 individuals, and results show that CCR5-Δ32 allele frequency has remained unchanged in this region of Central Europe over the last millennium, suggesting that there has been no strong positive selective pressure over this time period and confirming a more ancient origin for the allele.

  1. Analysis of HLA class II haplotypes in the Cayapa indians of ecuador: A novel DRBI allele reveals evidence for convergent evolution and balancing selection at position 86

    Energy Technology Data Exchange (ETDEWEB)

    Titus-Trachtenberg, E.A.; Erlich, H. (Roche Molecular Systems, Alameda, CA (United States)); Rickards, O.; De Stefano, G.F. (Universita di Roma, Rome (Italy))

    1994-07-01

    PCR amplification, oligonucleotide probe typing, and sequencing were used to analyze the HLA class II loci (DRB1, DQA1, DAB1, and DPB1) of an isolated South Amerindian tribe. Here the authors report HLA class II variation, including the identification of a new DRB1 allele, several novel DR/DQ haplotypes, and an unusual distribution of DPB1 alleles, among the Cayapa Indians (N=100) of Ecuador. A general reduction of HLA class II allelic variation in the Cayapa is consistent with a population bottleneck during the colonization of the Americas. The new Cayapa DRB1 allele, DRB1[sup *]08042, which arose by a G[yields]T point mutation in the parental DRB1[sup *]0802, contains a novel Val codon (GTT) at position 86. The generation of DRB1[sup *]08042 (Val-86) from DRB1[sup *]0802 (Gly-86) in the Cayapa, by a different mechanism than the (GT[yields]TG) change in the creation of DRB1[sub *]08041 (Val-86) from DRB1[sup *]0802 in Africa, implicates selection in the convergent evolution of position 86 DR[beta] variants. The DRB1[sup *]08042 allele has not been found in >1,800 Amerindian haplotypes and thus presumably arose after the Cayapa separated from other South American Amerindians. Selection pressure for increased haplotype diversity can be inferred in the generation and maintenance of three new DRB1[sup *]08042 haplotypes and several novel DR/DQ haplotypes in this population. The DPB1 allelic distribution in the Cayapa is also extraordinary, with two alleles, DPB1[sup *]1401, a very rare allele in North American Amerindian populations, and DPB1[sup *]0402, the most common Amerindian DPB1 allele, constituting 89% of the Cayapa DPB1. These data are consistent with the postulated rapid rate of evolution as noted for the class I HLA-B locus of other South American Indians. 34 refs., 2 figs., 2 tabs.

  2. Mutation analysis in the long isoform of USH2A in American patients with Usher Syndrome type II.

    Science.gov (United States)

    Yan, Denise; Ouyang, Xiaomei; Patterson, D Michael; Du, Li Lin; Jacobson, Samuel G; Liu, Xue-Zhong

    2009-12-01

    Usher syndrome type II (USH2) is an autosomal recessive disorder characterized by moderate to severe hearing impairment and progressive visual loss due to retinitis pigmentosa (RP). To identify novel mutations and determine the frequency of USH2A mutations as a cause of USH2, we have carried out mutation screening of all 72 coding exons and exon-intron splice sites of the USH2A gene. A total of 20 USH2 American probands of European descent were analyzed using single strand conformational polymorphism (SSCP) and direct sequencing methods. Ten different USH2A mutations were identified in 55% of the probands, five of which were novel mutations. The detected mutations include three missense, three frameshifts and four nonsense mutations, with c.2299delG/p.E767fs mutation, accounting for 38.9% of the pathological alleles. Two cases were homozygotes, two cases were compound heterozygotes and one case had complex allele with three variants. In seven probands, only one USH2A mutation was detected and no pathological mutation was found in the remaining eight individuals. Altogether, our data support the fact that c.2299delG/p.E767fs is indeed the most common USH2A mutation found in USH2 patients of European Caucasian background. Thus, if screening for mutations in USH2A is considered, it is reasonable to screen for the c.2299delG mutation first.

  3. Spectrum of rhodopsin mutations in Korean patients with retinitis pigmentosa

    Science.gov (United States)

    Kim, Kwang Joong; Kim, Cinoo; Bok, Jeong; Kim, Kyung-Seon; Lee, Eun-Ju; Park, Sung Pyo; Chung, Hum; Han, Bok-Ghee; Kim, Hyung-Lae; Kimm, Kuchan; Yu, Hyeong Gon

    2011-01-01

    Purpose To determine the spectrum and frequency of rhodopsin gene (RHO) mutations in Korean patients with retinitis pigmentosa (RP) and to characterize genotype–phenotype correlations in patients with mutations. Methods The RHO mutations were screened by direct sequencing, and mutation prevalence was measured in patients and controls. The impact of missense mutations to RP was predicted by segregation analysis, peptide sequence alignment, and in silico analysis. The severity of disease in patients with the missense mutations was compared by visual acuity, electroretinography, optical coherence tomography, and kinetic visual field testing. Results Five heterozygous mutations were identified in six of 302 probands with RP, including a novel mutation (c.893C>A, p.A298D) and four known mutations (c.50C>T, p.T17M; c.533A>G, p.Y178C; c.888G>T, p.K296N; and c.1040C>T, p.P347L). The allele frequency of missense mutations was measured in 114 ethnically matched controls. p.A298D, newly identified in a sporadic patient, had never been found in controls and was predicted to be pathogenic. Among the patients with the missense mutations, we observed the most severe phenotype in patients with p.P347L, less severe phenotypes in patients with p.Y178C or p.A298D, and a relatively moderate phenotype in a patient with p.T17M. Conclusions The results reveal the spectrum of RHO mutations in Korean RP patients and clinical features that vary according to mutations. Our findings will be useful for understanding these genetic spectra and the genotype–phenotype correlations and will therefore help with predicting disease prognosis and facilitating the development of gene therapy. PMID:21677794

  4. Early maturing mutations as germplasm stocks for barley breeding

    International Nuclear Information System (INIS)

    Ukai, Yasuo

    1985-01-01

    A total of 102 early maturing mutations have been isolated after various treatments of seeds or plants with ionizing radiations or chemicals from a barley cultivar 'Chikurin Ibaraki 1' or its mutants. Fifty of them were evaluated as regards responses to internal physiological factors. The mutants were found to have a mutational alteration in vernalization and/or photoperiodic response. Earliness in a narrow sense was not noticeably changed. The original genotype is a winter and long-day type. By mutation four different degrees of change in vernalization requirement i.e. complete (V 1 ) and incomplete (V 2 ) spring habit and winter habit with reduced requirement to varying degrees (V 3 , V 4 ) have been produced. Photoperiodic response was also changed into at least three types i.e. complete (P 1 ) and incomplete (P 2 ) loss of sensitivity to short photoperiod and a slight reduction in critical daylength for heading. P 1 and P 2 type mutants were all characterized by marked earliness in heading time in field. Thirty seven mutants were located in seven separate loci. Allelism test of the mutated genes to spontaneous ones revealed that the genes carried by P 1 type mutants were all allelic to an earliness gene ea sub(k) on chromosome 5 and the gene involved in P 2 type mutants to ea 7 on chromosome 6. On the contrary, the gene commonly involved in all V 1 type mutants and one V 2 type mutant was not allelic to spring habit gene Sh 2 or Sh 3 . It seemed likely that the gene was not allelic to, either, but closely linked with sh on chromosome 4. The diversity in terms of genetic and physiological properties of the early maturing mutants arising from common ancestry emphasizes the importance of induced mutation in broadening of germplasm of barley breeding. (author)

  5. Assigning breed origin to alleles in crossbred animals.

    Science.gov (United States)

    Vandenplas, Jérémie; Calus, Mario P L; Sevillano, Claudia A; Windig, Jack J; Bastiaansen, John W M

    2016-08-22

    For some species, animal production systems are based on the use of crossbreeding to take advantage of the increased performance of crossbred compared to purebred animals. Effects of single nucleotide polymorphisms (SNPs) may differ between purebred and crossbred animals for several reasons: (1) differences in linkage disequilibrium between SNP alleles and a quantitative trait locus; (2) differences in genetic backgrounds (e.g., dominance and epistatic interactions); and (3) differences in environmental conditions, which result in genotype-by-environment interactions. Thus, SNP effects may be breed-specific, which has led to the development of genomic evaluations for crossbred performance that take such effects into account. However, to estimate breed-specific effects, it is necessary to know breed origin of alleles in crossbred animals. Therefore, our aim was to develop an approach for assigning breed origin to alleles of crossbred animals (termed BOA) without information on pedigree and to study its accuracy by considering various factors, including distance between breeds. The BOA approach consists of: (1) phasing genotypes of purebred and crossbred animals; (2) assigning breed origin to phased haplotypes; and (3) assigning breed origin to alleles of crossbred animals based on a library of assigned haplotypes, the breed composition of crossbred animals, and their SNP genotypes. The accuracy of allele assignments was determined for simulated datasets that include crosses between closely-related, distantly-related and unrelated breeds. Across these scenarios, the percentage of alleles of a crossbred animal that were correctly assigned to their breed origin was greater than 90 %, and increased with increasing distance between breeds, while the percentage of incorrectly assigned alleles was always less than 2 %. For the remaining alleles, i.e. 0 to 10 % of all alleles of a crossbred animal, breed origin could not be assigned. The BOA approach accurately assigns

  6. Mutations in the p53 homolog p63: allele-specific developmental syndromes in humans.

    NARCIS (Netherlands)

    Bokhoven, J.H.L.M. van; McKeon, F.

    2002-01-01

    p63 is the most recently discovered but most ancient member of the p53 family. In marked contrast to p53, p63 is highly expressed in embryonic ectoderm and in the basal, regenerative layers of many epithelial tissues in the adult. The p63-knockout mouse dies at birth and lacks limbs, epidermis,

  7. Sequenza: allele-specific copy number and mutation profiles from tumor sequencing data

    DEFF Research Database (Denmark)

    Favero, Francesco; Joshi, Tejal; Marquard, Andrea Marion

    2015-01-01

    : Comparison between Sequenza/exome and SNP/ASCAT revealed strong correlation in cellularity (Pearson’s r = 0.90) and ploidy estimates (r = 0.42, or r = 0.94 after manual inspecting alternative solutions). This performance was noticeably superior to previously published algorithms. In addition, in artificial...

  8. Chloroplast mutations induced by 9-aminoacridine hydrochloride are independent of the plastome mutator in Oenothera.

    Science.gov (United States)

    GuhaMajumdar, M; Baldwin, S; Sears, B B

    2004-02-01

    Oenothera plants homozygous for the recessive plastome mutator allele ( pm) show chloroplast DNA (cpDNA) mutation frequencies that are about 1,000-fold higher than spontaneous levels. The pm-encoded gene product has been hypothesized to have a function in cpDNA replication, repair and/or mutation avoidance. Previous chemical mutagenesis experiments with the alkylating agent nitroso-methyl urea (NMU) showed a synergistic effect of NMU on the induction of mutations in the pm line, suggesting an interaction between the pm-encoded gene product and one of the repair systems that corrects alkylation damage. The goal of the experiments described here was to examine whether the pm activity extends to the repair of damage caused by non-alkylating mutagens. To this end, the intercalating mutagen, 9-aminoacridine hydrochloride (9AA) was tested for synergism with the plastome mutator. A statistical analysis of the data reported here indicates that the pm-encoded gene product is not involved in the repair of the 9AA-induced mutations. However, the recovery of chlorotic sectors in plants derived from the mutagenized seeds shows that 9AA can act as a mutagen of the chloroplast genome.

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

    Science.gov (United States)

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

    2016-06-14

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

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

    Science.gov (United States)

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

    2008-12-01

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

  11. De novo constitutional MLH1 epimutations confer early-onset colorectal cancer in two new sporadic Lynch syndrome cases, with derivation of the epimutation on the paternal allele in one.

    Science.gov (United States)

    Goel, Ajay; Nguyen, Thuy-Phuong; Leung, Hon-Chiu E; Nagasaka, Takeshi; Rhees, Jennifer; Hotchkiss, Erin; Arnold, Mildred; Banerji, Pia; Koi, Minoru; Kwok, Chau-To; Packham, Deborah; Lipton, Lara; Boland, C Richard; Ward, Robyn L; Hitchins, Megan P

    2011-02-15

    Lynch syndrome is an autosomal dominant cancer predisposition syndrome classically caused by germline mutations of the mismatch repair genes, MLH1, MSH2, MSH6 and PMS2. Constitutional epimutations of the MLH1 gene, characterized by soma-wide methylation of a single allele of the promoter and allelic transcriptional silencing, have been identified in a subset of Lynch syndrome cases lacking a sequence mutation in MLH1. We report two individuals with no family history of colorectal cancer who developed that disease at age 18 and 20 years. In both cases, cancer had arisen because of the de novo occurrence of a constitutional MLH1 epimutation and somatic loss-of-heterozygosity of the functional allele in the tumors. We show for the first time that the epimutation in one case arose on the paternally inherited allele. Analysis of 13 tumors from seven individuals with constitutional MLH1 epimutations showed eight tumors had lost the second MLH1 allele, two tumors had a novel pathogenic missense mutation and three had retained heterozygosity. Only 1 of 12 tumors demonstrated the BRAF V600E mutation and 3 of 11 tumors harbored a mutation in KRAS. The finding that epimutations can originate on the paternal allele provides important new insights into the mechanism of origin of epimutations. It is clear that the second hit in MLH1 epimutation-associated tumors typically has a genetic not epigenetic basis. Individuals with mismatch repair-deficient cancers without the BRAF V600E mutation are candidates for germline screening for sequence or methylation changes in MLH1. Copyright © 2010 UICC.

  12. Marker-Assisted Selection for Recognizing Wheat Mutant Genotypes Carrying HMW Glutenin Alleles Related to Baking Quality

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Zamani

    2014-01-01

    Full Text Available Allelic diversity of HMW glutenin loci in several studies revealed that allelic combinations affect dough quality. Dx5 + Dy10 subunits are related to good baking quality and Dx2 + Dy12 are related to undesirable baking quality. One of the most regular methods to evaluate the baking quality is SDS-PAGE which is used to improve baking quality labs. Marker-assisted selection is the method which can recognize the alleles related to baking quality and this method is based on polymerase chain reaction. 10 pairs of specific primers related to Dx2, Dx2.1, Dx5, Dy10, and Dy12 subunits were used for recognizing baking quality of some wheat varieties and some mutant genotypes. Only 5 pairs of them could show the specific bands. All subunits were recognized by the primers except Dx2.1. Some of the primers were extracted from previous studies and the others were designed based on D genome subunits of wheat. SDS-PAGE method accomplished having confidence in these marker’s results. To realize the effect of mutation, seed storage proteins were measured. It showed that mutation had effect on the amount of seed storage protein on the mutant seeds (which showed polymorphism.

  13. Marker-assisted selection for recognizing wheat mutant genotypes carrying HMW glutenin alleles related to baking quality.

    Science.gov (United States)

    Zamani, Mohammad Javad; Bihamta, Mohammad Reza; Naserian Khiabani, Behnam; Tahernezhad, Zahra; Hallajian, Mohammad Taher; Shamsi, Marzieh Varasteh

    2014-01-01

    Allelic diversity of HMW glutenin loci in several studies revealed that allelic combinations affect dough quality. Dx5 + Dy10 subunits are related to good baking quality and Dx2 + Dy12 are related to undesirable baking quality. One of the most regular methods to evaluate the baking quality is SDS-PAGE which is used to improve baking quality labs. Marker-assisted selection is the method which can recognize the alleles related to baking quality and this method is based on polymerase chain reaction. 10 pairs of specific primers related to Dx2, Dx2.1, Dx5, Dy10, and Dy12 subunits were used for recognizing baking quality of some wheat varieties and some mutant genotypes. Only 5 pairs of them could show the specific bands. All subunits were recognized by the primers except Dx2.1. Some of the primers were extracted from previous studies and the others were designed based on D genome subunits of wheat. SDS-PAGE method accomplished having confidence in these marker's results. To realize the effect of mutation, seed storage proteins were measured. It showed that mutation had effect on the amount of seed storage protein on the mutant seeds (which showed polymorphism).

  14. Frequency of the MDR1 mutant allele associated with multidrug sensitivity in dogs from Brazil

    Directory of Open Access Journals (Sweden)

    Monobe MM

    2015-04-01

    Full Text Available Marina M Monobe,1 João P Araujo Junior,2 Kari V Lunsford,3 Rodrigo C Silva,4 Camilo Bulla41Department of Veterinary Clinics, School of Veterinary Medicine and Animal Science, 2Department of Microbiology and Immunology, Biosciences Institute, Sao Paulo State University (UNESP, Botucatu, Brazil; 3Department of Clinical Sciences and Animal Health Center, 4Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Mississippi, MS, USAAbstract: To date, a 4-bp deletion in the MDR1 gene has been detected in more than ten dog breeds, as well as in mixed breed dogs, in several countries, however information regarding this mutation in dogs from Brazil is lacking. For this reason, 103 Collies, 77 Border Collies, 76 Shetland Sheepdogs, 20 Old English Sheepdogs, 55 German Shepherds, 16 Australian Shepherds, and 53 Whippets from Brazil were screened for the presence of the mutation. The heterozygous mutated genotype, MDR1 (+/−, frequency found for Collies, Australian Shepherd, and Shetland Sheepdog was 50.5% (95% CI =41.1%–59.9%, 31.3% (95% CI =8.6%–53.2%, and 15.8% (95% CI =7.7%–23.9%, respectively. Homozygous mutated genotype, MDR1 (−/−, was detected only in Collies 35.9%. The MDR1 allele mutant frequency found for Collies, Australian Shepherd, and Shetland Sheepdog was 61.2% (95% CI =54.8%–67.5%, 15.6% (95% CI =3.1%–28.2%, and 7.9% (95% CI =3.7%–12.1%, respectively. Additionally, even free of the mutant allele, the maximum mutant prevalence (MMP in that population, with 95% CI, was 3.8%, 5.2%, 5.4%, and 13.8% for Border Collies, German Shepherds, Whippets, and Old English Sheepdogs, respectively. In this way, this information is important, not only for MDR1 genotype-based breeding programs and international exchange of breeding animals of predisposed breeds, but also for modification of drug therapy for breeds at risk.Keywords: P-glycoprotein, MDR1 mutation, ivermectin, dog, drug

  15. Polymorphism of κ-Casein in Italian Goat Breeds: A New ACRS-PCR Designed DNA Test for Discrimination of A and B Alleles

    Directory of Open Access Journals (Sweden)

    Vlatka Cubric-Curik

    2002-01-01

    Full Text Available The objective of this study was to develop a DNA test for rapid characterisation of goat κ-casein (κ-CN A and B variants and to study this polymorphism in Italian goat breeds. Genetic polymorphism of κ-CN gene was, in addition to isoelectric focusing, analysed according to a new technique designated as amplification created restriction site. Two alleles that differ in one nucleotide mutation (G Ø A in exon 4 were characterised. The 167-bp PCR product surrounding the nucleotide mutation was amplified from genomic DNA and the PCR product was digested with MaeIII. After digestion the A allele gives three fragments of 77, 65 and 25 bp in comparison with the B allele which gives two fragments of 90 and 77 bp. The analysis of allele frequency distribution at κ-CN locus, based on 401 individual samples, revealed significant differences among three goat breeds from the north of Italy (Nera di Verzasca, Frontalasca and Alpine with frequency of κ-CN B allele around 0.3, versus two goat breeds from the south of Italy (Maltese and Sarda with frequency of κ-CN B allele around 0.5. While two goat breeds (Maltese and Nera di Verzasca did not show significant deviations from the Hardy-Weinberg equilibrium, a highly significant excess of heterozygote genotype (AB was observed in Alpine, Frontalasca and Sarda goats. Here the developed DNA method and observed relatively high frequency of κ-CN B allele give a prerequisite for the assessment of research related to the simultaneous estimation of the effects of composite αs1/κ-CN genotypes on milk production and cheese-making properties.

  16. Allelic imbalance and cytogenetic deletion of 1p in colorectal adenomas: a target region identified between DIS199 and DIS234

    DEFF Research Database (Denmark)

    Bomme, L; Heim, S; Bardi, G

    1998-01-01

    short-term cultured and karyotyped colorectal adenomas for allelic imbalance at eight microsatellite loci in 1p. Allelic imbalances were detected in seven of the 12 adenomas that had cytogenetically visible abnormalities of chromosome 1, as well as in four adenomas that either had a normal karyotype...... region. This genomic area contains the human homologue of the tumor modifier gene Mom1 (1p35-36.1), which, in mice, modifies the number of intestinal tumors in multiple intestinal neoplasia (Min)-mutated animals. To evaluate whether the imbalances corresponded to interstitial deletions of 1p material, we...

  17. Dynamic ligand modulation of EPO receptor pools, and dysregulation by polycythemia-associated EPOR alleles.

    Directory of Open Access Journals (Sweden)

    Seema Singh

    Full Text Available Erythropoietin (EPO and its cell surface receptor (EPOR are essential for erythropoiesis; can modulate non-erythroid target tissues; and have been reported to affect the progression of certain cancers. Basic studies of EPOR expression and trafficking, however, have been hindered by low-level EPOR occurrence, and the limited specificity of anti-EPOR antibodies. Consequently, these aspects of EPOR biology are not well defined, nor are actions of polycythemia- associated mutated EPOR alleles. Using novel rabbit monoclonal antibodies to intracellular, PY- activated and extracellular EPOR domains, the following properties of the endogenous hEPOR in erythroid progenitors first are unambiguously defined. 1 High- Mr EPOR forms become obviously expressed only when EPO is limited. 2 EPOR-68K plus -70K species sequentially accumulate, and EPOR-70K comprises an apparent cell surface EPOR population. 3 Brefeldin A, N-glycanase and associated analyses point to EPOR-68K as a core-glycosylated intracellular EPOR pool (of modest size. 4 In contrast to recent reports, EPOR inward trafficking is shown (in UT7epo cells, and primary proerythroblasts to be sharply ligand-dependent. Beyond this, when C-terminal truncated hEPOR-T mutant alleles as harbored by polycythemia patients are co-expressed with the wild-type EPOR in EPO-dependent erythroid progenitors, several specific events become altered. First, EPOR-T alleles are persistently activated upon EPO- challenge, yet are also subject to apparent turn-over (to low-Mr EPOR products. Furthermore, during exponential cell growth EPOR-T species become both over-represented, and hyper-activated. Interestingly, EPOR-T expression also results in an EPO dose-dependent loss of endogenous wild-type EPOR's (and, therefore, a squelching of EPOR C-terminal- mediated negative feedback effects. New knowledge concerning regulated EPOR expression and trafficking therefore is provided, together with new insight into mechanisms via

  18. Dynamic Ligand Modulation of EPO Receptor Pools, and Dysregulation by Polycythemia-Associated EPOR Alleles

    Science.gov (United States)

    Singh, Seema; Verma, Rakesh; Pradeep, Anamika; Leu, Karen; Mortensen, R. Bruce; Young, Peter R.; Oyasu, Miho; Schatz, Peter J.; Green, Jennifer M.; Wojchowski, Don M.

    2012-01-01

    Erythropoietin (EPO) and its cell surface receptor (EPOR) are essential for erythropoiesis; can modulate non-erythroid target tissues; and have been reported to affect the progression of certain cancers. Basic studies of EPOR expression and trafficking, however, have been hindered by low-level EPOR occurrence, and the limited specificity of anti-EPOR antibodies. Consequently, these aspects of EPOR biology are not well defined, nor are actions of polycythemia- associated mutated EPOR alleles. Using novel rabbit monoclonal antibodies to intracellular, PY- activated and extracellular EPOR domains, the following properties of the endogenous hEPOR in erythroid progenitors first are unambiguously defined. 1) High- Mr EPOR forms become obviously expressed only when EPO is limited. 2) EPOR-68K plus -70K species sequentially accumulate, and EPOR-70K comprises an apparent cell surface EPOR population. 3) Brefeldin A, N-glycanase and associated analyses point to EPOR-68K as a core-glycosylated intracellular EPOR pool (of modest size). 4) In contrast to recent reports, EPOR inward trafficking is shown (in UT7epo cells, and primary proerythroblasts) to be sharply ligand-dependent. Beyond this, when C-terminal truncated hEPOR-T mutant alleles as harbored by polycythemia patients are co-expressed with the wild-type EPOR in EPO-dependent erythroid progenitors, several specific events become altered. First, EPOR-T alleles are persistently activated upon EPO- challenge, yet are also subject to apparent turn-over (to low-Mr EPOR products). Furthermore, during exponential cell growth EPOR-T species become both over-represented, and hyper-activated. Interestingly, EPOR-T expression also results in an EPO dose-dependent loss of endogenous wild-type EPOR's (and, therefore, a squelching of EPOR C-terminal- mediated negative feedback effects). New knowledge concerning regulated EPOR expression and trafficking therefore is provided, together with new insight into mechanisms via which

  19. Homozygous germ-line mutation of the PMS2 mismatch repair gene: a unique case report of constitutional mismatch repair deficiency (CMMRD)

    OpenAIRE

    Ramchander, N. C.; Ryan, N. A. J.; Crosbie, E. J.; Evans, D. G.

    2017-01-01

    BackgroundConstitutional mismatch repair deficiency syndrome results from bi-allelic inheritance of mutations affecting the key DNA mismatch repair genes: MLH1, MSH2, MSH6 or PMS2. Individuals with bi-allelic mutations have a dysfunctional mismatch repair system from birth; as a result, constitutional mismatch repair deficiency syndrome is characterised by early onset malignancies. Fewer than 150 cases have been reported in the literature over the past 20 years. This is the first report of th...

  20. Mutations in the VNTR of the carboxyl-ester lipase gene (CEL) are a rare cause of monogenic diabetes

    DEFF Research Database (Denmark)

    Torsvik, Janniche; Johansson, Stefan; Johansen, Anders

    2009-01-01

    of the VNTR, and determined the VNTR-length of each allele. When blindly testing 56 members of the two families with known single-base deletions in the CEL VNTR, the method correctly assessed the mutation carriers. Screening of 241 probands from suspected maturity-onset diabetes of the young (MODY) families...... negative for mutations in known MODY genes (95 individuals from Denmark and 146 individuals from UK) revealed no deletions in the proximal repeats of the CEL VNTR. However, we found one Danish patient with a short, novel CEL allele containing only three VNTR repeats (normal range 7-23 in healthy controls......). This allele co-segregated with diabetes or impaired glucose tolerance in the patient's family as six of seven mutation carriers were affected. We also identified individuals who had three copies of a complete CEL VNTR. In conclusion, the CEL gene is highly polymorphic, but mutations in CEL are likely...

  1. A Simple, High-Throughput Assay for Fragile X Expanded Alleles Using Triple Repeat Primed PCR and Capillary Electrophoresis

    Science.gov (United States)

    Lyon, Elaine; Laver, Thomas; Yu, Ping; Jama, Mohamed; Young, Keith; Zoccoli, Michael; Marlowe, Natalia

    2010-01-01

    Population screening has been proposed for Fragile X syndrome to identify premutation carrier females and affected newborns. We developed a PCR-based assay capable of quickly detecting the presence or absence of an expanded FMR1 allele with high sensitivity and specificity. This assay combines a triplet repeat primed PCR with high-throughput automated capillary electrophoresis. We evaluated assay performance using archived samples sent for Fragile X diagnostic testing representing a range of Fragile X CGG-repeat expansions. Two hundred five previously genotyped samples were tested with the new assay. Data were analyzed for the presence of a trinucleotide “ladder” extending beyond 55 repeats, which was set as a cut-off to identify expanded FMR1 alleles. We identified expanded FMR1 alleles in 132 samples (59 premutation, 71 full mutation, 2 mosaics) and normal FMR1 alleles in 73 samples. We found 100% concordance with previous results from PCR and Southern blot analyses. In addition, we show feasibility of using this assay with DNA extracted from dried-blood spots. Using a single PCR combined with high-throughput fragment analysis on the automated capillary electrophoresis instrument, we developed a rapid and reproducible PCR-based laboratory assay that meets many of the requirements for a first-tier test for population screening. PMID:20431035

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

    DEFF Research Database (Denmark)

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

    2005-01-01

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

  3. Analysis of nucleotide diversity among alleles of the major bacterial blight resistance gene Xa27 in cultivars of rice (Oryza sativa) and its wild relatives.

    Science.gov (United States)

    Bimolata, Waikhom; Kumar, Anirudh; Sundaram, Raman Meenakshi; Laha, Gouri Shankar; Qureshi, Insaf Ahmed; Reddy, Gajjala Ashok; Ghazi, Irfan Ahmad

    2013-08-01

    Xa27 is one of the important R-genes, effective against bacterial blight disease of rice caused by Xanthomonas oryzae pv. oryzae (Xoo). Using natural population of Oryza, we analyzed the sequence variation in the functionally important domains of Xa27 across the Oryza species. DNA sequences of Xa27 alleles from 27 rice accessions revealed higher nucleotide diversity among the reported R-genes of rice. Sequence polymorphism analysis revealed synonymous and non-synonymous mutations in addition to a number of InDels in non-coding regions of the gene. High sequence variation was observed in the promoter region including the 5'UTR with 'π' value 0.00916 and 'θ w ' = 0.01785. Comparative analysis of the identified Xa27 alleles with that of IRBB27 and IR24 indicated the operation of both positive selection (Ka/Ks > 1) and neutral selection (Ka/Ks ≈ 0). The genetic distances of alleles of the gene from Oryza nivara were nearer to IRBB27 as compared to IR24. We also found the presence of conserved and null UPT (upregulated by transcriptional activator) box in the isolated alleles. Considerable amino acid polymorphism was localized in the trans-membrane domain for which the functional significance is yet to be elucidated. However, the absence of functional UPT box in all the alleles except IRBB27 suggests the maintenance of single resistant allele throughout the natural population.

  4. Somatic Mutations and Clonal Hematopoiesis in Aplastic Anemia.

    Science.gov (United States)

    Yoshizato, Tetsuichi; Dumitriu, Bogdan; Hosokawa, Kohei; Makishima, Hideki; Yoshida, Kenichi; Townsley, Danielle; Sato-Otsubo, Aiko; Sato, Yusuke; Liu, Delong; Suzuki, Hiromichi; Wu, Colin O; Shiraishi, Yuichi; Clemente, Michael J; Kataoka, Keisuke; Shiozawa, Yusuke; Okuno, Yusuke; Chiba, Kenichi; Tanaka, Hiroko; Nagata, Yasunobu; Katagiri, Takamasa; Kon, Ayana; Sanada, Masashi; Scheinberg, Phillip; Miyano, Satoru; Maciejewski, Jaroslaw P; Nakao, Shinji; Young, Neal S; Ogawa, Seishi

    2015-07-02

    In patients with acquired aplastic anemia, destruction of hematopoietic cells by the immune system leads to pancytopenia. Patients have a response to immunosuppressive therapy, but myelodysplastic syndromes and acute myeloid leukemia develop in about 15% of the patients, usually many months to years after the diagnosis of aplastic anemia. We performed next-generation sequencing and array-based karyotyping using 668 blood samples obtained from 439 patients with aplastic anemia. We analyzed serial samples obtained from 82 patients. Somatic mutations in myeloid cancer candidate genes were present in one third of the patients, in a limited number of genes and at low initial variant allele frequency. Clonal hematopoiesis was detected in 47% of the patients, most frequently as acquired mutations. The prevalence of the mutations increased with age, and mutations had an age-related signature. DNMT3A-mutated and ASXL1-mutated clones tended to increase in size over time; the size of BCOR- and BCORL1-mutated and PIGA-mutated clones decreased or remained stable. Mutations in PIGA and BCOR and BCORL1 correlated with a better response to immunosuppressive therapy and longer and a higher rate of overall and progression-free survival; mutations in a subgroup of genes that included DNMT3A and ASXL1 were associated with worse outcomes. However, clonal dynamics were highly variable and might not necessarily have predicted the response to therapy and long-term survival among individual patients. Clonal hematopoiesis was prevalent in aplastic anemia. Some mutations were related to clinical outcomes. A highly biased set of mutations is evidence of Darwinian selection in the failed bone marrow environment. The pattern of somatic clones in individual patients over time was variable and frequently unpredictable. (Funded by Grant-in-Aid for Scientific Research and others.).

  5. Birth prevalence and mutation spectrum in danish patients with autosomal recessive albinism

    DEFF Research Database (Denmark)

    Grønskov, Karen; Ek, Jakob; Sand, Annie

    2009-01-01

    PURPOSE: The study was initiated to investigate the mutation spectrum of four OCA genes and to calculate the birth prevalence in patients with autosomal recessive albinism. METHODS: Mutation analysis using dHPLC or direct DNA sequencing of TYR, OCA2, TYRP1, and MATP was performed in 62 patients....... Two mutations in one OCA gene explained oculocutaneous albinism (OCA) in 44% of the patients. Mutations in TYR were found in 26% of patients, while OCA2 and MATP caused OCA in 15% and 3%, respectively. No mutations were found in TYRP1. Of the remaining 56% of patients, 29% were heterozygous...... for a mutation in either TYR or OCA2, and 27% were without mutations in any of the four genes. Exclusive expression of the mutant allele was found in four heterozygous patients. A minimum birth prevalence of 1 in 14,000 was calculated, based on register data on 218 patients. The proportion of OCA to autosomal...

  6. Gene structure and mutant alleles of PCDH15: nonsyndromic deafness DFNB23 and type 1 Usher syndrome.

    Science.gov (United States)

    Ahmed, Zubair M; Riazuddin, Saima; Aye, Sandar; Ali, Rana A; Venselaar, Hanka; Anwar, Saima; Belyantseva, Polina P; Qasim, Muhammad; Riazuddin, Sheikh; Friedman, Thomas B

    2008-10-01

    Mutations of PCDH15, encoding protocadherin 15, can cause either combined hearing and vision impairment (type 1 Usher syndrome; USH1F) or nonsyndromic deafness (DFNB23). Human PCDH15 is reported to be composed of 35 exons and encodes a variety of isoforms with 3-11 ectodomains (ECs), a transmembrane domain and a carboxy-terminal cytoplasmic domain (CD). Building on these observations, we describe an updated gene structure that has four additional exons of PCDH15 and isoforms that can be subdivided into four classes. Human PCDH15 encodes three alternative, evolutionarily conserved unique cytoplasmic domains (CD1, CD2 or CD3). Families ascertained on the basis of prelingual hearing loss were screened for linkage of this phenotype to markers for PCDH15 on chromosome 10q21.1. In seven of twelve families segregating USH1, we identified homozygous mutant alleles (one missense, one splice site, three nonsense and two deletion mutations) of which six are novel. One family was segregating nonsyndromic deafness DFNB23 due to a homozygous missense mutation. To date, in our cohort of 557 Pakistani families, we have found 11 different PCDH15 mutations that account for deafness in 13 families. Molecular modeling provided mechanistic insight into the phenotypic variation in severity of the PCDH15 missense mutations. We did not find pathogenic mutations in five of the twelve USH1 families linked to markers for USH1F, which suggest either the presence of mutations of yet additional undiscovered exons of PCDH15, mutations in the introns or regulatory elements of PCDH15, or an additional locus for type I USH at chromosome 10q21.1.

  7. Mannose-binding lectin variant alleles and HLA-DR4 alleles are associated with giant cell arteritis

    DEFF Research Database (Denmark)

    Jacobsen, Soren; Baslund, Bo; Madsen, Hans O.

    2002-01-01

    /GCA, MBL variant alleles were associated with signs of increased inflammatory activity and clinical signs of arteritic manifestations. This was not found for HLA-DR4 alleles. These findings indicate that HLA-DR4 and MBL are contributing to the pathophysiology of GCA at different levels in the disease...... alleles in controls, patients with PMR only, and patients with GCA was 37, 32, and 53% (p = 0.01), respectively. HLA-DRB1*04 was found in 47% of patients with PMR only and in 54% of patients with GCA, which differed significantly from the 35% found in controls (p = 0.01). HLA-DR4 alleles were...... not associated with any clinical phenotypes of PMR/GCA, whereas MBL variant alleles were associated with cranial arteritis, high erythrocyte sedimentation rate, and low B-hemoglobin. CONCLUSION: We found MBL variant alleles and HLA-DR4 alleles to be weak susceptibility markers for GCA. In patients with PMR...

  8. Mosaicism of an ELANE mutation in an asymptomatic mother in a familial case of cyclic neutropenia.

    Science.gov (United States)

    Hirata, Osamu; Okada, Satoshi; Tsumura, Miyuki; Karakawa, Shuhei; Matsumura, Itaru; Kimura, Yujiro; Maihara, Toshiro; Yasunaga, Shin'ichiro; Takihara, Yoshihiro; Ohara, Osamu; Kobayashi, Masao

    2015-07-01

    To confirm and characterize mosaicism of the cyclic neutropenia (CyN)-related mutation in the ELANE gene identified in the asymptomatic mother of patients with CyN. We identified sibling cases with CyN due to a novel heterozygous splicing site mutation, IVS4 +5SD G>T, in the ELANE gene, resulting in an internal in-frame deletion of 30 nucleotides (corresponding to a ten amino acid deletion, V161-F170). The mutated allele was also detected in their asymptomatic mother but at low frequency. We measured the frequency of the mutant allele from peripheral blood leukocytes (PBLs) by subcloning, and confirmed the allelic frequency of mosaicism in various cell types by massively parallel DNA sequencing (MPS) analysis. In the subcloning analysis, the mutant allele was identified in 21.36 % of PBLs from the asymptomatic mother, compared with 54.72 % of PBLs from the CyN patient. In the MPS analysis, the mutant allele was observed in approximately 30 % of mononuclear cells, CD3(+) T cells, CD14(+) monocytes and the buccal mucosa. Conversely, it was detected in low frequency in polymorphonuclear leukocytes (PLMLs) (3-4 %) and CD16(+) granulocytes (2-3 %). Mosaicism of the ELANE mutation has only previously been identified in one confirmed and one unconfirmed case of SCN. This is the first report of mosaicism of the ELANE mutation in a case of CyN. The MPS results suggest that this de novo mutation occurred during the two-cell stage of embryogenesis. PLMLs expressing the ELANE mutation were found to be actively undergoing apoptosis.

  9. Generation of an allelic series of knock-in mice using recombinase-mediated cassette exchange (RMCE).

    Science.gov (United States)

    Roebroek, Anton J M; Van Gool, Bart

    2014-01-01

    Molecular genetic strategies applying embryonic stem cell (ES cell) technologies to study the function of a gene in mice or to generate a mouse model for a human disease are continuously under development. Next to (conditional) inactivation of genes the application and importance of approaches to generate knock-in mutations are increasing. In this chapter the principle and application of recombinase-mediated cassette exchange (RMCE) are discussed as being a new emerging knock-in strategy, which enables easy generation of a series of different knock-in mutations within one gene. An RMCE protocol, which was used to generate a series of different knock-in mutations in the Lrp1 gene of ES cells, is described in detail as an example of how RMCE can be used to generate highly efficiently an allelic series of differently modified ES cell clones from a parental modified ES cell clone. Subsequently the differently modified ES cell clones can be used to generate an allelic series of mutant knock-in mice.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-10-24

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

  11. Mutations in the ABCA4 (ABCR) gene are the major cause of autosomal recessive cone-rod dystrophy.

    Science.gov (United States)

    Maugeri, A; Klevering, B J; Rohrschneider, K; Blankenagel, A; Brunner, H G; Deutman, A F; Hoyng, C B; Cremers, F P

    2000-10-01

    The photoreceptor cell-specific ATP-binding cassette transporter gene (ABCA4; previously denoted "ABCR") is mutated, in most patients, with autosomal recessive (AR) Stargardt disease (STGD1) or fundus flavimaculatus (FFM). In addition, a few cases with AR retinitis pigmentosa (RP) and AR cone-rod dystrophy (CRD) have been found to have ABCA4 mutations. To evaluate the importance of the ABCA4 gene as a cause of AR CRD, we selected 5 patients with AR CRD and 15 patients from Germany and The Netherlands with isolated CRD. Single-strand conformation-polymorphism analysis and sequencing revealed 19 ABCA4 mutations in 13 (65%) of 20 patients. In six patients, mutations were identified in both ABCA4 alleles; in seven patients, mutations were detected in one allele. One complex ABCA4 allele (L541P;A1038V) was found exclusively in German patients with CRD; one patient carried this complex allele homozygously, and five others were compound heterozygous. These findings suggest that mutations in the ABCA4 gene are the major cause of AR CRD. A primary role of the ABCA4 gene in STGD1/FFM and AR CRD, together with the gene's involvement in an as-yet-unknown proportion of cases with AR RP, strengthens the idea that mutations in the ABCA4 gene could be the most frequent cause of inherited retinal dystrophy in humans.

  12. Wilson's disease in Southern Brazil: genotype-phenotype correlation and description of two novel mutations in ATP7B gene

    Directory of Open Access Journals (Sweden)

    Ricardo Schmitt de Bem

    2013-08-01

    Full Text Available OBJECTIVE: Wilson's disease (WD is an inborn error of metabolism caused by abnormalities of the copper-transporting protein encoding gene ATP7B. In this study, we examined ATP7B for mutations in a group of patients living in southern Brazil. METHODS: 36 WD subjects were studied and classified according to their clinical and epidemiological data. In 23 subjects the ATP7B gene was analyzed. RESULTS: Fourteen distinct mutations were detected in at least one of the alleles. The c.3207C>A substitution at exon 14 was the most common mutation (allelic frequency=37.1% followed by the c.3402delC at exon 15 (allelic frequency=11.4%. The mutations c.2018-2030del13 at exon 7 and c.4093InsT at exon 20 are being reported for the first time. CONCLUSION: The c.3207C>A substitution at exon 14, was the most common mutation, with an allelic frequency of 37.1%. This mutation is the most common mutation described in Europe.

  13. Nanolock-Nanopore Facilitated Digital Diagnostics of Cancer Driver Mutation in Tumor Tissue.

    Science.gov (United States)

    Wang, Yong; Tian, Kai; Shi, Ruicheng; Gu, Amy; Pennella, Michael; Alberts, Lindsey; Gates, Kent S; Li, Guangfu; Fan, Hongxin; Wang, Michael X; Gu, Li-Qun

    2017-07-28

    Cancer driver mutations are clinically significant biomarkers. In precision medicine, accurate detection of these oncogenic changes in patients would enable early diagnostics of cancer, individually tailored targeted therapy, and precise monitoring of treatment response. Here we investigated a novel nanolock-nanopore method for single-molecule detection of a serine/threonine protein kinase gene BRAF V600E mutation in tumor tissues of thyroid cancer patients. The method lies in a noncovalent, mutation sequence-specific nanolock. We found that the nanolock formed on the mutant allele/probe duplex can separate the duplex dehybridization procedure into two sequential steps in the nanopore. Remarkably, this stepwise unzipping kinetics can produce a unique nanopore electric marker, with which a single DNA molecule of the cancer mutant allele can be unmistakably identified in various backgrounds of the normal wild-type allele. The single-molecule sensitivity for mutant allele enables both binary diagnostics and quantitative analysis of mutation occurrence. In the current configuration, the method can detect the BRAF V600E mutant DNA lower than 1% in the tumor tissues. The nanolock-nanopore method can be adapted to detect a broad spectrum of both transversion and transition DNA mutations, with applications from diagnostics to targeted therapy.

  14. Dynamic of Mutational Events in Variable Number Tandem Repeats of Escherichia coli O157:H7

    Directory of Open Access Journals (Sweden)

    A. V. Bustamante

    2013-01-01

    Full Text Available VNTRs regions have been successfully used for bacterial subtyping; however, the hypervariability in VNTR loci is problematic when trying to predict the relationships among isolates. Since few studies have examined the mutation rate of these markers, our aim was to estimate mutation rates of VNTRs specific for verotoxigenic E. coli O157:H7. The knowledge of VNTR mutational rates and the factors affecting them would make MLVA more effective for epidemiological or microbial forensic investigations. For this purpose, we analyzed nine loci performing parallel, serial passage experiments (PSPEs on 9 O157:H7 strains. The combined 9 PSPE population rates for the 8 mutating loci ranged from 4.4 × 10−05 to 1.8 × 10−03 mutations/generation, and the combined 8-loci mutation rate was of 2.5 × 10−03 mutations/generation. Mutations involved complete repeat units, with only one point mutation detected. A similar proportion between single and multiple repeat changes was detected. Of the 56 repeat mutations, 59% were insertions and 41% were deletions, and 72% of the mutation events corresponded to O157-10 locus. For alleles with up to 13 UR, a constant and low mutation rate was observed; meanwhile longer alleles were associated with higher and variable mutation rates. Our results are useful to interpret data from microevolution and population epidemiology studies and particularly point out that the inclusion or not of O157-10 locus or, alternatively, a differential weighting data according to the mutation rates of loci must be evaluated in relation with the objectives of the proposed study.

  15. Immunodeficiency associated with FCN3 mutation and ficolin-3 deficiency

    DEFF Research Database (Denmark)

    Munthe-Fog, Lea; Hummelshøj, Tina; Honoré, Christian

    2009-01-01

    Ficolin-3, encoded by the FCN3 gene and expressed in the lung and liver, is a recognition molecule in the lectin pathway of the complement system. Heterozygosity for an FCN3 frameshift mutation (rs28357092), leading to a distortion of the C-terminal end of the molecule, occurs in people without...... disease (allele frequency among whites, 0.01). We describe a patient with recurrent infections who was homozygous for this mutation, who had undetectable serum levels of ficolin-3, and who had a deficiency in ficolin-3-dependent complement activation....

  16. Exome mutation burden predicts clinical outcome in ovarian cancer carrying mutated BRCA1 and BRCA2 genes

    DEFF Research Database (Denmark)

    Birkbak, Nicolai Juul; Kochupurakkal, Bose; Gonzalez-Izarzugaza, Jose Maria

    2013-01-01

    drugs and relative to non-mutation carriers present a favorable clinical outcome following therapy. Genome sequencing studies have shown a high number of mutations in the tumor genome in patients carrying BRCA1 or BRCA2 mutations (mBRCA). The present study used exome-sequencing and SNP 6 array data...... between low Nmut and shorter PFS and OS in mBRCA HGSOC by Cox regression and Kaplan-Meier analyses. The association was also significant when the analysis was limited to germline BRCA1 or BRCA2 mutated patients with SNP array-determined loss of heterozygosity of the BRCA1 or BRCA2 locus in the tumors....... In the mBRCA HGSOC tumors, Nmut was correlated with the genome fraction with loss of heterozygosity and with number of telomeric allelic imbalance, genomic measures evaluating chromosomal instability. However, no significant association between Nmut and PFS or OS was found in HGSOC carrying wild-type BRCA1...

  17. Comprehensive mutational profiling of core binding factor acute myeloid leukemia.

    Science.gov (United States)

    Duployez, Nicolas; Marceau-Renaut, Alice; Boissel, Nicolas; Petit, Arnaud; Bucci, Maxime; Geffroy, Sandrine; Lapillonne, Hélène; Renneville, Aline; Ragu, Christine; Figeac, Martin; Celli-Lebras, Karine; Lacombe, Catherine; Micol, Jean-Baptiste; Abdel-Wahab, Omar; Cornillet, Pascale; Ifrah, Norbert; Dombret, Hervé; Leverger, Guy; Jourdan, Eric; Preudhomme, Claude

    2016-05-19

    Acute myeloid leukemia (AML) with t(8;21) or inv(16) have been recognized as unique entities within AML and are usually reported together as core binding factor AML (CBF-AML). However, there is considerable clinical and biological heterogeneity within this group of diseases, and relapse incidence reaches up to 40%. Moreover, translocations involving CBFs are not sufficient to induce AML on its own and the full spectrum of mutations coexisting with CBF translocations has not been elucidated. To address these issues, we performed extensive mutational analysis by high-throughput sequencing in 215 patients with CBF-AML enrolled in the Phase 3 Trial of Systematic Versus Response-adapted Timed-Sequential Induction in Patients With Core Binding Factor Acute Myeloid Leukemia and Treating Patients with Childhood Acute Myeloid Leukemia with Interleukin-2 trials (age, 1-60 years). Mutations in genes activating tyrosine kinase signaling (including KIT, N/KRAS, and FLT3) were frequent in both subtypes of CBF-AML. In contrast, mutations in genes that regulate chromatin conformation or encode members of the cohesin complex were observed with high frequencies in t(8;21) AML (42% and 18%, respectively), whereas they were nearly absent in inv(16) AML. High KIT mutant allele ratios defined a group of t(8;21) AML patients with poor prognosis, whereas high N/KRAS mutant allele ratios were associated with the lack of KIT or FLT3 mutations and a favorable outcome. In addition, mutations in epigenetic modifying or cohesin genes were associated with a poor prognosis in patients with tyrosine kinase pathway mutations, suggesting synergic cooperation between these events. These data suggest that diverse cooperating mutations may influence CBF-AML pathophysiology as well as clinical behavior and point to potential unique pathogenesis of t(8;21) vs inv(16) AML. © 2016 by The American Society of Hematology.

  18. allelic variation of hmw glutenin subunits of ethiopian bread wheat

    African Journals Online (AJOL)

    journal

    High molecular weight glutenins are often effective in identifying wheat (Triticum ... There were highly significant differences between genotypes and banding ... was without deliberate selection pressure towards high Glu-1 scoring alleles ...

  19. Association mapping and favorable QTL alleles for fiber quality traits ...

    Indian Academy of Sciences (India)

    A total of 201 markers were polymorphic and generated 394 ... identified favorable QTL alleles and typical accessions for fiber quality are excellent genetic resources for future cotton .... Field management followed respective local practices.

  20. Apolipoprotein e4 allele and cognitive decline in elderly men

    NARCIS (Netherlands)

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

    1994-01-01

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

  1. PMS2 mutations in childhood cancer.

    Science.gov (United States)

    De Vos, Michel; Hayward, Bruce E; Charlton, Ruth; Taylor, Graham R; Glaser, Adam W; Picton, Susan; Cole, Trevor R; Maher, Eamonn R; McKeown, Carole M E; Mann, Jill R; Yates, John R; Baralle, Diana; Rankin, Julia; Bonthron, David T; Sheridan, Eamonn

    2006-03-01

    Until recently, the PMS2 DNA mismatch repair gene has only rarely been implicated as a cancer susceptibility locus. New studies have shown, however, that earlier analyses of this gene have had technical limitations and also that the genetic behavior of mutant PMS2 alleles is unusual, in that, unlike MLH1 or MSH2 mutations, PMS2 mutations show low heterozygote penetrance. As a result, a dominantly inherited cancer predisposition has not been a feature reported in families with PMS2 mutations. Such families have instead been ascertained through childhood-onset cancers in homozygotes or through apparently sporadic colorectal cancer in heterozygotes. We present further information on the phenotype associated with homozygous PMS2 deficiency in 13 patients from six families of Pakistani origin living in the United Kingdom. This syndrome is characterized by café-au-lait skin pigmentation and a characteristic tumor spectrum, including leukemias, lymphomas, cerebral malignancies (such as supratentorial primitive neuroectodermal tumors, astrocytomas, and glioblastomas), and colorectal neoplasia with an onset in early adult life. We present evidence for a founder effect in five families, all of which carried the same R802-->X mutation (i.e., arginine-802 to stop) in PMS2. This cancer syndrome can be mistaken for neurofibromatosis type 1, with important management implications including the risk of the disorder occurring in siblings and the likelihood of tumor development in affected individuals.

  2. DRD4 dopamine receptor allelic diversity in various primate species

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, M.; Higley, D. [NIAAA, Rockville, MD (United States); O`Brien, S. [NCI, Frederick, MD (United States)] [and others

    1994-09-01

    The DRD4 dopamine receptor is uniquely characterized by a 48 bp repeating segment within the coding region, located in exon III. Different DRD4 alleles are produced by the presence of additional 48 bp repeats, each of which adds 16 amino acids to the length of the 3rd intracytoplasmic loop of the receptor. The DRD4 receptor is therefore an intriguing candidate gene for behaviors which are influenced by dopamine function. In several human populations, DRD4 alleles with 2-8 and 10 repeats have previously been identified, and the 4 and 7 repeat alleles are the most abundant. We have determined DRD4 genotypes in the following nonhuman primate species: chimpanzee N=2, pygmy chimpanzee N=2, gorilla N=4, siamang N=2, Gelada baboon N=1, gibbon N=1, orangutan (Bornean and Sumatran) N=62, spider monkey N=4, owl monkey N=1, Colobus monkey N=1, Patas monkey N=1, ruffed lemur N=1, rhesus macaque N=8, and vervet monkey N=28. The degree of DRD4 polymorphism and which DRD4 alleles were present both showed considerable variation across primate species. In contrast to the human, rhesus macaque monkeys were monomorphic. The 4 and 7 repeat allels, highly abundant in the human, may not be present in certain other primates. For example, the four spider monkeys we studied showed the 7, 8 and 9 repeat length alleles and the only gibbon we analyzed was homozygous for the 9 repeat allele (thus far not observed in the human). Genotyping of other primate species and sequencing of the individual DRD4 repeat alleles in different species may help us determine the ancestral DRD4 repeat length and identify connections between DRD4 genotype and phenotype.

  3. Allele frequency distribution for 21 autosomal STR loci in Nepal.

    Science.gov (United States)

    Kraaijenbrink, T; van Driem, G L; Opgenort, J R M L; Tuladhar, N M; de Knijff, P

    2007-05-24

    The allele frequency distributions of 21 autosomal loci contained in the AmpFlSTR Identifiler, the Powerplex 16 and the FFFL multiplex PCR kits, was studied in 953 unrelated individuals from Nepal. Several new alleles (i.e. not yet reported in the NIST Short Tandem Repeat DNA Internet DataBase [http://www.cstl.nist.gov/biotech/strbase/]) have been detected in the process.

  4. Clinical and molecular response to interferon-α therapy in essential thrombocythemia patients with CALR mutations.

    Science.gov (United States)

    Verger, Emmanuelle; Cassinat, Bruno; Chauveau, Aurélie; Dosquet, Christine; Giraudier, Stephane; Schlageter, Marie-Hélène; Ianotto, Jean-Christophe; Yassin, Mohammed A; Al-Dewik, Nader; Carillo, Serge; Legouffe, Eric; Ugo, Valerie; Chomienne, Christine; Kiladjian, Jean-Jacques

    2015-12-10

    Myeloproliferative neoplasms are clonal disorders characterized by the presence of several gene mutations associated with particular hematologic parameters, clinical evolution, and prognosis. Few therapeutic options are available, among which interferon α (IFNα) presents interesting properties like the ability to induce hematologic responses (HRs) and molecular responses (MRs) in patients with JAK2 mutation. We report on the response to IFNα therapy in a cohort of 31 essential thrombocythemia (ET) patients with CALR mutations (mean follow-up of 11.8 years). HR was achieved in all patients. Median CALR mutant allelic burden (%CALR) significantly decreased from 41% at baseline to 26% after treatment, and 2 patients even achieved complete MR. In contrast, %CALR was not significantly modified in ET patients treated with hydroxyurea or aspirin only. Next-generation sequencing identified additional mutations in 6 patients (affecting TET2, ASXL1, IDH2, and TP53 genes). The presence of additional mutations was associated with poorer MR on CALR mutant clones, with only minor or no MRs in this subset of patients. Analysis of the evolution of the different variant allele frequencies showed that the mutated clones had a differential sensitivity to IFNα in a given patient, but no new mutation emerged during treatment. In all, this study shows that IFNα induces high rates of HRs and MRs in CALR-mutated ET, and that the presence of additional nondriver mutations may influence the MR to therapy. © 2015 by The American Society of Hematology.

  5. Novel SLC19A3 Promoter Deletion and Allelic Silencing in Biotin-Thiamine-Responsive Basal Ganglia Encephalopathy.

    Directory of Open Access Journals (Sweden)

    Irene Flønes

    Full Text Available Biotin-thiamine responsive basal ganglia disease is a severe, but potentially treatable disorder caused by mutations in the SLC19A3 gene. Although the disease is inherited in an autosomal recessive manner, patients with typical phenotypes carrying single heterozygous mutations have been reported. This makes the diagnosis uncertain and may delay treatment.In two siblings with early-onset encephalopathy dystonia and epilepsy, whole-exome sequencing revealed a novel single heterozygous SLC19A3 mutation (c.337T>C. Although Sanger-sequencing and copy-number analysis revealed no other aberrations, RNA-sequencing in brain tissue suggested the second allele was silenced. Whole-genome sequencing resolved the genetic defect by revealing a novel 45,049 bp deletion in the 5'-UTR region of the gene abolishing the promoter. High dose thiamine and biotin therapy was started in the surviving sibling who remains stable. In another patient two novel compound heterozygous SLC19A3 mutations were found. He improved substantially on thiamine and biotin therapy.We show that large genomic deletions occur in the regulatory region of SLC19A3 and should be considered in genetic testing. Moreover, our study highlights the power of whole-genome sequencing as a diagnostic tool for rare genetic disorders across a wide spectrum of mutations including non-coding large genomic rearrangements.

  6. Rules for resolving Mendelian inconsistencies in nuclear pedigrees typed for two-allele markers.

    Directory of Open Access Journals (Sweden)

    Sajjad Ahmad Khan

    Full Text Available Gene-mapping studies, regularly, rely on examination for Mendelian transmission of marker alleles in a pedigree as a way of screening for genotyping errors and mutations. For analysis of family data sets, it is, usually, necessary to resolve or remove the genotyping errors prior to consideration. At the Center of Inherited Disease Research (CIDR, to deal with their large-scale data flow, they formalized their data cleaning approach in a set of rules based on PedCheck output. We scrutinize via carefully designed simulations that how well CIDR's data cleaning rules work in practice. We found that genotype errors in siblings are detected more often than in parents for less polymorphic SNPs and vice versa for more polymorphic SNPs. Through computer simulations, we conclude that some of the CIDR's rules work poorly in some circumstances, and we suggest a set of modified data cleaning rules that may work better than CIDR's rules.

  7. Telomeric Allelic Imbalance Indicates Defective DNA Repair and Sensitivity to DNA-Damaging Agents

    DEFF Research Database (Denmark)

    Birkbak, Nicolai J.; Wang, Zhigang C.; Kim, Ji-Young

    2012-01-01

    with triple-negative breast cancer (TNBC). In serous ovarian cancer treated with platinum-based chemotherapy, higher levels of NtAI forecast a better initial response. We found an inverse relationship between BRCA1 expression and NtAI in sporadic TNBC and serous ovarian cancers without BRCA1 or BRCA2 mutation...... of defective DNA repair in cell lines and tumors and correlated these signatures to platinum sensitivity. The number of subchromosomal regions with allelic imbalance extending to the telomere (NtAI) predicted cisplatin sensitivity in vitro and pathologic response to preoperative cisplatin treatment in patients...... also benefit from these agents. NtAI, a genomic measure of unfaithfully repaired DNA, may identify cancer patients likely to benefit from treatments targeting defective DNA repair. Cancer Discov; 2(4); 366–75. ©2012 AACR. This article is highlighted in the In This Issue feature, p. 288...

  8. ALEA: a toolbox for allele-specific epigenomics analysis.

    Science.gov (United States)

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

    2014-04-15

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

  9. Allele-specific MMP-3 transcription under in vivo conditions

    Energy Technology Data Exchange (ETDEWEB)

    Chaoyong, Zhu [Atherosclerosis Research Unit, King Gustav V Research Institute, Department of Medicine, Karolinska Institute, Stockholm (Sweden); Odeberg, Jacob [Atherosclerosis Research Unit, King Gustav V Research Institute, Department of Medicine, Karolinska Institute, Stockholm (Sweden); Department of Biotechnology, AlbaNova University Center, Royal Institute of Technology, Stockholm (Sweden); Hamsten, Anders [Atherosclerosis Research Unit, King Gustav V Research Institute, Department of Medicine, Karolinska Institute, Stockholm (Sweden); Eriksson, Per [Atherosclerosis Research Unit, King Gustav V Research Institute, Department of Medicine, Karolinska Institute, Stockholm (Sweden)

    2006-09-29

    A common matrix metalloproteinases-3 (MMP-3) -1612 5A/6A promoter polymorphism is associated with risk for cardiovascular disease, rheumatoid arthritis, and other diseases. Here we used the haplotype chromatin immunoprecipitation method to study allele-specific MMP-3 expression under in vivo conditions in heterozygous THP-1 cells. Pyrosequencing was used to analyse the ratio of 5A-allele to 6A-allele after chromatin immunoprecipitation using an antibody against phosphorylated active RNA polymerase II. There was no allele-specific difference in transcriptional activity during basal conditions, i.e., in unstimulated monocytic THP-1 cells. However, after stimulation of MMP-3 expression by monocyte differentiation or incubation with IL-1{beta}, the haplotype containing the 5A-allele was associated with higher transcriptional activity compared with the 6A-containing haplotype. Electromobility shift assay demonstrated increased binding of nuclear proteins to the 5A-allele after monocyte differentiation. In conclusion, the common MMP-3 5A/6A promoter polymorphism appears to be functional only during specific environmental conditions involving inflammation.

  10. Origin of allelic diversity in antirrhinum S locus RNases.

    Science.gov (United States)

    Xue, Y; Carpenter, R; Dickinson, H G; Coen, E S

    1996-01-01

    In many plant species, self-incompatibility (SI) is genetically controlled by a single multiallelic S locus. Previous analysis of S alleles in the Solanaceae, in which S locus ribonucleases (S RNases) are responsible for stylar expression of SI, has demonstrated that allelic diversity predated speciation within this family. To understand how allelic diversity has evolved, we investigated the molecular basis of gametophytic SI in Antirrhinum, a member of the Scrophulariaceae, which is closely related to the Solanaceae. We have characterized three Antirrhinum cDNAs encoding polypeptides homologous to S RNases and shown that they are encoded by genes at the S locus. RNA in situ hybridization revealed that the Antirrhinum S RNase are primarily expressed in the stylar transmitting tissue. This expression is consistent with their proposed role in arresting the growth of self-pollen tubes. S alleles from the Scrophulariaceae form a separate group from those of the Solanaceae, indicating that new S alleles have been generated since these families separated (approximately 40 million years). We propose that the recruitment of an ancestral RNase gene into SI occurred during an early stage of angiosperm evolution and that, since that time, new alleles subsequently have arisen at a low rate. PMID:8672882

  11. Suspension Array for Multiplex Detection of Eight Fungicide-Resistance Related Alleles in Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    Xin Zhang

    2016-09-01

    Full Text Available A simple and high-throughput assay to detect fungicide resistance is required for large-scale monitoring of the emergence of resistant strains of Botrytis cinerea. Using suspension array technology performed on a Bio-Plex 200 System, we developed a single-tube allele-specific primer extension (ASPE assay that can simultaneously detect eight alleles in one reaction. These eight alleles include E198 and 198A of the β-Tubulin gene (BenA, H272 and 272Y of the Succinate dehydrogenase iron–sulfur subunit gene (SdhB, I365 and 365S of the putative osmosensor histidine kinase gene (BcOS1, and F412 and 412S of the 3-ketoreductase gene (erg27. This assay was first established and optimized with eight plasmid templates containing the DNA sequence variants BenA-E198, BenA-198A, SdhB-H272, SdhB-272Y, BcOS1-I365, BcOS1-365S, erg27-F412, and erg27-412S. Results indicated that none of the probes showed cross-reactivity with one another. The minimum limit of detection for these genotypes was one copy per test. Four mutant plasmids were mixed with 10 ng/μL wild-type genomic DNA in different ratios. Detection sensitivity of mutant loci was 0.45% for BenA-E198A, BcOS1-I365S, and erg27-F412S, and was 4.5% for SdhB-H272Y. A minimum quantity of 0.1 ng of genomic DNA was necessary to obtain reliable results. This is the first reported assay that can simultaneously detect mutations in BenA, SdhB, BcOS1, and erg27.

  12. Suspension Array for Multiplex Detection of Eight Fungicide-Resistance Related Alleles in Botrytis cinerea.

    Science.gov (United States)

    Zhang, Xin; Xie, Fei; Lv, Baobei; Zhao, Pengxiang; Ma, Xuemei

    2016-01-01

    A simple and high-throughput assay to detect fungicide resistance is required for large-scale monitoring of the emergence of resistant strains of Botrytis cinerea . Using suspension array technology performed on a Bio-Plex 200 System, we developed a single-tube allele-specific primer extension assay that can simultaneously detect eight alleles in one reaction. These eight alleles include E198 and 198A of the β-Tubulin gene ( BenA ), H272 and 272Y of the Succinate dehydrogenase iron-sulfur subunit gene ( SdhB) , I365 and 365S of the putative osmosensor histidine kinase gene ( BcOS1 ), and F412 and 412S of the 3-ketoreductase gene ( erg27 ). This assay was first established and optimized with eight plasmid templates containing the DNA sequence variants BenA- E198, BenA- 198A, SdhB- H272, SdhB- 272Y, BcOS1- I365, BcOS1- 365S, erg27 -F412, and erg27 -412S. Results indicated that none of the probes showed cross-reactivity with one another. The minimum limit of detection for these genotypes was one copy per test. Four mutant plasmids were mixed with 10 ng/μL wild-type genomic DNA in different ratios. Detection sensitivity of mutant loci was 0.45% for BenA- E198A, BcOS1- I365S, and erg27 -F412S, and was 4.5% for SdhB- H272Y. A minimum quantity of 0.1 ng of genomic DNA was necessary to obtain reliable results. This is the first reported assay that can simultaneously detect mutations in BenA , SdhB , BcOS1 , and erg27 .

  13. Detecting very low allele fraction variants using targeted DNA sequencing and a novel molecular barcode-aware variant caller.

    Science.gov (United States)

    Xu, Chang; Nezami Ranjbar, Mohammad R; Wu, Zhong; DiCarlo, John; Wang, Yexun

    2017-01-03

    Detection of DNA mutations at very low allele fractions with high accuracy will significantly improve the effectiveness of precision medicine for cancer patients. To achieve this goal through next generation sequencing, researchers need a detection method that 1) captures rare mutation-containing DNA fragments efficiently in the mix of abundant wild-type DNA; 2) sequences the DNA library extensively to deep coverage; and 3) distinguishes low level true variants from amplification and sequencing errors with high accuracy. Targeted enrichment using PCR primers provides researchers with a convenient way to achieve deep sequencing for a small, yet most relevant region using benchtop sequencers. Molecular barcoding (or indexing) provides a unique solution for reducing sequencing artifacts analytically. Although different molecular barcoding schemes have been reported in recent literature, most variant calling has been done on limited targets, using simple custom scripts. The analytical performance of barcode-aware variant calling can be significantly improved by incorporating advanced statistical models. We present here a highly efficient, simple and scalable enrichment protocol that integrates molecular barcodes in multiplex PCR amplification. In addition, we developed smCounter, an open source, generic, barcode-aware variant caller based on a Bayesian probabilistic model. smCounter was optimized and benchmarked on two independent read sets with SNVs and indels at 5 and 1% allele fractions. Variants were called with very good sensitivity and specificity within coding regions. We demonstrated that we can accurately detect somatic mutations with allele fractions as low as 1% in coding regions using our enrichment protocol and variant caller.

  14. Genomic analysis of a heterogeneous Mendelian phenotype: multiple novel alleles for inherited hearing loss in the Palestinian population

    Directory of Open Access Journals (Sweden)

    Walsh Tom

    2006-01-01

    Full Text Available Abstract Recessively inherited phenotypes are frequent in the Palestinian population, as the result of a historical tradition of marriages within extended kindreds, particularly in isolated villages. In order to characterise the genetics of inherited hearing loss in this population, we worked with West Bank schools for the deaf to identify children with prelingual, bilateral, severe to profound hearing loss not attributable to infection, trauma or other known environmental exposure. Of 156 families enrolled, hearing loss in 17 families (11 per cent was due to mutations in GJB2 (connexin 26, a smaller fraction of GJB2-associated deafness than in other populations. In order to estimate how many different genes might be responsible for hearing loss in this population, we evaluated ten families for linkage to all 36 known human autosomal deafness-related genes, fully sequencing hearing-related genes at any linked sites in informative relatives. Four families harboured four novel alleles of TMPRSS3 (988ΔA = 352stop, otoancorin (1067A >T = D356V and pendrin (716T > A = V239D and 1001G > T = 346stop. In each family, all affected individuals were homozygous for the critical mutation. Each allele was specific to one or a few families in the cohort; none were widespread. Since epidemiological tests of association of mutations with deafness were not feasible for such rare alleles, we used functional and bioinformatics approaches to evaluate their consequences. In six other families, hearing loss was not linked to any known gene, suggesting that these families harbour novel genes responsible for this phenotype. We conclude that inherited hearing loss is highly heterogeneous in this population, with most extended families acting as genetic isolates in this context. We also conclude that the same genes are responsible for hearing loss in this population as elsewhere, so that gene discovery in these families informs the genetics of hearing loss worldwide.

  15. HFE gene C282Y, H63D and S65C mutations frequency in the Transylvania region, Romania.

    Science.gov (United States)

    Trifa, Adrian P; Popp, Radu A; Militaru, Mariela S; Farcaş, Marius F; Crişan, Tania O; Gana, Ionuţ; Cucuianu, Andrei; Pop, Ioan V

    2012-06-01

    HFE-associated haemochromatosis is one of the most frequent autosomal recessive disorders in the Caucasian population. Although most of the cases are homozygous individuals for the C282Y mutation, another two mutations, H63D and S65C, have been reported to be associated with milder forms of the disease. This study was a first attempt to evaluate the distribution of these HFE gene mutations in the Transylvania region. Two-hundred and twenty-five healthy, unrelated volunteers originating from the Transylvania region, Romania, were screened for the HFE gene C282Y, H63D and S65C mutations, using molecular genetics assays (Polymerase Chain Reaction-Restriction Fragments Length Polymorphism). For the C282Y mutation, 7 heterozygotes (3.1%) were found, but no homozygous individual. In the case of the H63D mutation, 40 heterozygotes (17.8%) and 4 homozygotes (1.75%) for the mutant allele were evidenced. We found a compound heterozygous genotype (C282Y/H63D) in one individual (0.45%). Thus, the allele frequencies of the C282Y and H63D were 1.75% and 10.9%, respectively. Three individuals (1.3%) were found to harbour the S65C mutation in a heterozygous state, but none in a homozygous state: the allele frequency of the mutant allele was 0.75%. The distribution of the HFE gene C282Y, H63D and S65C mutations found in our group matches the tendencies observed in other European countries: a decreasing gradient from Northern to Southern Europe for the C282Y mutation; high frequency for the H63D mutation, and low frequency for the S65C mutation in most of the countries.

  16. Towards allele mining of bacterial wilt disease resistance gene in tomato

    International Nuclear Information System (INIS)

    Galvez, H.F.; Narciso, J.O.; Opina, N.L.; Canama, A.O.; Colle, M.G.; Latiza, M.A.; Caspillo, C.L.; Bituin, J.L.; Frankie, R.B.; Hautea, D.M.

    2005-01-01

    Tomato (Lycopersicon esculentum Mill.) is the most important vegetable commodity of the Philippines. Bacterial wilt caused by Ralstonia solanacearum is one serious constraint in tomato production particularly during off-season planting. A major locus derived from H7996 that confers resistance to bacterial wilt has been mapped in the tomato genome. To validate the biological function of the resistance locus and generate multiple allele -mimics-, targeted mutation was induced in tomato using gamma ray and ethyl methane sulfonate (EMS) mutagens. Suitable mutagen treatment was established by evaluating a wide range of mutagen doses/concentrations for a) percent seed germination, b) reduction in plant height, and c) loss of resistance. Six hundred Gy and 1.0% EMS were identified to generate large M1 families of H7996. From 10,000 initial seeds treated with either gamma ray or EMS, a total of 3,663 M1 plants were generated. M2 seeds were harvested from all surviving M1 plants. Several DNA markers have been resourced and are being developed specific to the bacterial wilt resistant gene. In the large M2 population, of H7996, both the phenotypic manifestation of bacterial wilt susceptibility and nucleotide changes in the resistance locus will be evaluated. Large M3 families for the different allele series of the bacterial wilt resistance gene will be established for future high throughput TILLING (Targeting Induced Local Lesions in Genomes) analysis in the gene region

  17. BRAF mutation testing in solid tumors: a methodological comparison.

    Science.gov (United States)

    Weyant, Grace W; Wisotzkey, Jeffrey D; Benko, Floyd A; Donaldson, Keri J

    2014-09-01

    Solid tumor genotyping has become standard of care for the characterization of proto-oncogene mutational status, which has traditionally been accomplished with Sanger sequencing. However, companion diagnostic assays and comparable laboratory-developed tests are becoming increasingly popular, such as the cobas 4800 BRAF V600 Mutation Test and the INFINITI KRAS-BRAF assay, respectively. This study evaluates and validates the analytical performance of the INFINITI KRAS-BRAF assay and compares concordance of BRAF status with two reference assays, the cobas test and Sanger sequencing. DNA extraction from FFPE tissue specimens was performed followed by multiplex PCR amplification and fluorescent label incorporation using allele-specific primer extension. Hybridization to a microarray, signal detection, and analysis were then performed. The limits of detection were determined by testing dilutions of mutant BRAF alleles within wild-type background DNA, and accuracy was calculated based on these results. The INFINITI KRAS-BRAF assay produced 100% concordance with the cobas test and Sanger sequencing and had sensitivity equivalent to the cobas assay. The INFINITI assay is repeatable with at least 95% accuracy in the detection of mutant and wild-type BRAF alleles. These results confirm that the INFINITI KRAS-BRAF assay is comparable to traditional sequencing and the Food and Drug Administration-approved companion diagnostic assay for the detection of BRAF mutations. Copyright © 2014 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  18. A silent allele in the locus D5S818 contained within the PowerPlex®21 PCR Amplification Kit.

    Science.gov (United States)

    Chen, Ling; Tai, Yunchun; Qiu, Pingming; Du, Weian; Liu, Chao

    2015-11-01

    Three paternity tests cases were found with a single locus mismatch at the locus D5S818 with PowerPlex®21 PCR Amplification Kit (Promega). Forward and reverse primers were redesigned to type the samples again and to evaluate if there were alleles dropped out. The results showed the existence of a silent allele 12 in all the three families, due to a point mutation that changed cytosine to adenine at 90 nucleotides upstream from the 5' end of the AGAT repeat sequences in all the six individuals. A single locus mismatch due to a silent allele may occur in any locus using any kit. Therefore, we recommend using multiple kits to confirm the results in paternity testing cases with mismatches, especially when there is a single locus mismatch with homozygote involved. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Hemochromatosis (HFE gene mutations in Brazilian chronic hemodialysis patients

    Directory of Open Access Journals (Sweden)

    F.V. Perícole

    2005-09-01

    Full Text Available Patients with chronic renal insufficiency (CRI have reduced hemoglobin levels, mostly as a result of decreased kidney production of erythropoietin, but the relation between renal insufficiency and the magnitude of hemoglobin reduction has not been well defined. Hereditary hemochromatosis is an inherited disorder of iron metabolism. The importance of the association of hemochromatosis with treatment for anemia among patients with CRI has not been well described. We analyzed the frequency of the C282Y and H63D mutations in the HFE gene in 201 Brazilian individuals with CRI undergoing hemodialysis. The analysis of the effects of HFE mutations on iron metabolism and anemia with biochemical parameters was possible in 118 patients of this study (hemoglobin, hematocrit, ferritin levels, transferrin saturation, and serum iron. A C282Y heterozygous mutation was found in 7/201 (3.4% and H63D homozygous and heterozygous mutation were found in 2/201 (1.0% and 46/201 (22.9%, respectively. The allelic frequencies of the HFE mutations (0.017 for C282Y mutation and 0.124 for H63D mutation did not differ between patients with CRI and healthy controls. Regarding the biochemical parameters, no differences were observed between HFE heterozygous and mutation-negative patients, although ferritin levels were not higher among patients with the H63D mutation (P = 0.08. From what we observed in our study, C282Y/H63D HFE gene mutations are not related to degrees of anemia or iron stores in CRI patients receiving intravenous iron supplementation (P > 0.10. Nevertheless, the present data suggest that the H63D mutation may have an important function as a modulating factor of iron overload in these patients.

  20. Novel USH2A mutations in Japanese Usher syndrome type 2 patients: marked differences in the mutation spectrum between the Japanese and other populations.

    Science.gov (United States)

    Nakanishi, Hiroshi; Ohtsubo, Masafumi; Iwasaki, Satoshi; Hotta, Yoshihiro; Usami, Shin-Ichi; Mizuta, Kunihiro; Mineta, Hiroyuki; Minoshima, Shinsei

    2011-07-01

    Usher syndrome (USH) is an autosomal recessive disorder characterized by retinitis pigmentosa and hearing loss. USH type 2 (USH2) is the most common type of USH and is frequently caused by mutations in USH2A. In a recent mutation screening of USH2A in Japanese USH2 patients, we identified 11 novel mutations in 10 patients and found the possible frequent mutation c.8559-2A>G in 4 of 10 patients. To obtain a more precise mutation spectrum, we analyzed further nine Japanese patients in this study. We identified nine mutations, of which eight were novel. This result indicates that the mutation spectrum for USH2A among Japanese patients largely differs from Caucasian, Jewish and Palestinian patients. Meanwhile, we did not find the c.8559-2A>G in this study. Haplotype analysis of the c.8559-2G (mutated) alleles using 23 single nucleotide polymorphisms surrounding the mutation revealed an identical haplotype pattern of at least 635 kb in length, strongly suggesting that the mutation originated from a common ancestor. The fact that all patients carrying c.8559-2A>G came from western Japan suggests that the mutation is mainly distributed in that area; indeed, most of the patients involved in this study came from eastern Japan, which contributed to the absence of c.8559-2A>G.

  1. pfmdr1 Amplification and Fixation of pfcrt Chloroquine Resistance Alleles in Plasmodium falciparum in Venezuela ▿ †

    Science.gov (United States)

    Griffing, Sean; Syphard, Luke; Sridaran, Sankar; McCollum, Andrea M.; Mixson-Hayden, Tonya; Vinayak, Sumiti; Villegas, Leopoldo; Barnwell, John W.; Escalante, Ananias A.; Udhayakumar, Venkatachalam

    2010-01-01

    Molecular tools are valuable for determining evolutionary history and the prevalence of drug-resistant malaria parasites. These tools have helped to predict decreased sensitivity to antimalarials and fixation of multidrug resistance genotypes in some regions. In order to assess how historical drug policies impacted Plasmodium falciparum in Venezuela, we examined molecular changes in genes associated with drug resistance. We examined pfmdr1 and pfcrt in samples from Sifontes, Venezuela, and integrated our findings with earlier work describing dhfr and dhps in these samples. We characterized pfmdr1 genotypes and copy number variation, pfcrt genotypes, and proximal microsatellites in 93 samples originating from surveillance from 2003 to 2004. Multicopy pfmdr1 was found in 12% of the samples. Two pfmdr1 alleles, Y184F/N1042D/D1246Y (37%) and Y184F/S1034C/N1042D/D1246Y (63%), were found. These alleles share ancestry, and no evidence of strong selective pressure on mutations was found. pfcrt chloroquine resistance alleles are fixed with two alleles: StctVMNT (91%) and SagtVMNT (9%). These alleles are associated with strong selection. There was also an association between pfcrt, pfmdr1, dhfr, and dhps genotypes/haplotypes. Duplication of pfmdr1 suggests a potential shift in mefloquine sensitivity in this region, which warrants further study. A bottleneck occurred in P. falciparum in Sifontes, Venezuela, and multidrug resistance genotypes are present. This population could be targeted for malaria elimination programs to prevent the possible spread of multidrug-resistant parasites. PMID:20145087

  2. Identification of a new defective SERPINA1 allele (PI*Zla palma) encoding an alpha-1-antitrypsin with altered glycosylation pattern.

    Science.gov (United States)

    Hernández-Pérez, José M; Ramos-Díaz, Ruth; Pérez, José A

    2017-10-01

    Alpha-1-antitrypsin (AAT) deficiency is a genetic condition that arises from mutations in the SERPINA1 gene and predisposes to develop pulmonary emphysema and, less frequently, liver disease. Occasionally, new defective SERPINA1 alleles are detected as an outcome of targeted-screening programs or case-findings. This study began with a female patient showing bronchial hyperreactivity. Serum level and phenotype for AAT was analysed by immunonephelometry and isoelectric focusing electrophoresis. The SERPINA1 gene of the proband was genotyped by PCR amplification and DNA sequencing. Analysis of AAT deficiency was extended to the proband's family. An abnormal AAT variant that migrated to a more cathodal position than PiZ AAT was detected in the proband's serum. Genetic analysis demonstrated that proband is heterozygous for a new defective SERPINA1 allele (PI*Z la palma ) characterized by the c.321C > A (p.Asn83Lys) mutation in the M1Val213 background. This mutation abolishes the N-glycosylation site in position 83 of the mature AAT. Eight relatives of the proband are carriers of the PI*Z la palma allele and four of them have shown symptoms of bronchial asthma or bronchial hyperreactivity. The mean α1AT level in the serum of PI*MZ la palma individuals was 87.1 mg/dl. The reduction in circulating AAT levels associated to the PI*Z la palma allele was similar to that of PI*Z allele, representing a risk of impairment in lung function. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Mutations of the phenylalanine hydroxylase gene in patients with phenylketonuria in Shanxi, China

    Directory of Open Access Journals (Sweden)

    Yong-An Zhou

    2012-01-01

    Full Text Available The variation in mutations in exons 3, 6, 7, 11 and 12 of the phenylalanine hydroxylase (PAH gene was investigated in 59 children with phenylketonuria (PKU and 100 normal children. Three single nucleotide polymorphisms were detected by sequence analysis. The mutational frequencies of cDNA 696, cDNA 735 and cDNA 1155 in patients were 96.2%, 76.1% and 7.6%, respectively, whereas in healthy children the corresponding frequencies were 97.0%, 77.3% and 8.3%. In addition, 81 mutations accounted for 61.0% of the mutant alleles. R111X, H64 > TfsX9 and S70 del accounted for 5.1%, 0.8% and 0.8% mutation of alleles in exon 3, whereas EX6-96A > G accounted for 10.2% mutation of alleles in exon 6. R243Q had the highest incidence in exon 7 (12.7%, followed by Ivs7 +2T>A (5.1% and T278I (2.5%. G247V, R252Q, L255S, R261Q and E280K accounted for 0.8% while Y356X and V399V accounted for 5.9% and 5.1%, respectively, in exon 11. R413P and A434D accounted for 5.9% and 2.5%, respectively, in exon 12. Seventy-two variant alleles accounted for the 16 mutations observed here. The mutation characteristics and distributions demonstrated that EX6-96A > G and R243Q were the hot regions for mutations in the PAH gene in Shanxi patients with PKU.

  4. Procedures for identifying S-allele genotypes of Brassica.

    Science.gov (United States)

    Wallace, D H

    1979-11-01

    Procedures are described for efficient selection of: (1) homozygous and heterozygous S-allele genotypes; (2) homozygous inbreds with the strong self- and sib-incompatibility required for effective seed production of single-cross F1 hybrids; (3) heterozygous genotypes with the high self- and sib-incompatibility required for effective seed production of 3- and 4-way hybrids.From reciprocal crosses between two first generation inbred (I1) plants there are three potential results: both crosses are incompatible; one is incompatible and the other compatible; and both are compatible. Incompatibility of both crosses is useful information only when combined with data from other reciprocal crosses. Each compatible cross, depending on whether its reciprocal is incompatible or compatible, dictates alternative reasoning and additional reciprocal crosses for efficiently and simultaneously identifying: (A) the S-allele genotype of all individual I1 plants, and (B) the expressions of dominance or codominance in pollen and stigma (sexual organs) of an S-allele heterozygous genotype. Reciprocal crosses provide the only efficient means of identifying S-allele genotypes and also the sexual-organ x S-allele-interaction types.Fluorescent microscope assay of pollen tube penetration into the style facilitates quantitation within 24-48 hours of incompatibility and compatibility of the reciprocal crosses. A procedure for quantitating the reciprocal difference is described that maximizes informational content of the data about interactions between S alleles in pollen and stigma of the S-allele-heterozygous genotype.Use of the non-inbred Io generation parent as a 'known' heterozygous S-allele genotype in crosses with its first generation selfed (I1) progeny usually reduces at least 7 fold the effort required for achieving objectives 1, 2, and 3, compared to the method of making reciprocal crosses only among I1 plants.Identifying the heterozygous and both homozygous S-allele genotypes during

  5. Linkage of familial Alzheimer disease to chromosome 14 in two large early-onset pedigrees: effects of marker allele frequencies on lod scores.

    Science.gov (United States)

    Nechiporuk, A; Fain, P; Kort, E; Nee, L E; Frommelt, E; Polinsky, R J; Korenberg, J R; Pulst, S M

    1993-05-01

    Alzheimer disease (AD) is a devastating neurodegenerative disease leading to global dementia. In addition to sporadic forms of AD, familial forms (FAD) have been recognized. Mutations in the amyloid precursor protein (APP) gene on chromosome (CHR) 21 have been shown to cause early-onset AD in a small number of pedigrees. Recently, linkage to markers on CHR 14 has been established in several early-onset FAD pedigrees. We now report lod scores for CHR 14 markers in two large early-onset FAD pedigrees. Pairwise linkage analysis suggested that in these pedigrees the mutation is tightly linked to the loci D14S43 and D14S53. However, assumptions regarding marker allele frequencies had a major and often unpredictable effect on calculated lod scores. Therefore, caution needs to be exercised when single pedigrees are analyzed with marker allele frequencies determined from the literature or from a pool of spouses.

  6. N-glycosylation of asparagine 8 regulates surface expression of major histocompatibility complex class I chain-related protein A (MICA) alleles dependent on threonine 24

    DEFF Research Database (Denmark)

    Pedersen, Maiken Mellergaard; Skovbakke, Sarah Line; Schneider, Christine L.

    2014-01-01

    for cell-surface expression and sought to identify the essential residues. We found that a single N-glycosylation site (N8) was important for MICA018 surface expression. The frequently expressed MICA allele 008, with an altered transmembrane and intracellular domain, was not affected by mutation of this N......-glycosylation site. Mutational analysis revealed that a single amino acid (T24) in the extracellular domain of MICA018 was essential for the N-glycosylation dependency, while the intracellular domain was not involved. The HHV7 immunoevasin, U21, was found to inhibit MICA018 surface expression by affecting N......-glycosylation and the retention was rescued by T24A substitution. Our study reveals N-glycosylation as an allele-specific regulatory mechanism important for regulation of surface expression of MICA018 and we pinpoint the residues essential for this N-glycosylation dependency. In addition we show that this regulatory mechanism...

  7. Dominant Drop mutants are gain-of-function alleles of the muscle segment homeobox gene (msh) whose overexpression leads to the arrest of eye development.

    Science.gov (United States)

    Mozer, B A

    2001-05-15

    Dominant Drop (Dr) mutations are nearly eyeless and have additional recessive phenotypes including lethality and patterning defects in eye and sensory bristles due to cis-regulatory lesions in the cell cycle regulator string (stg). Genetic analysis demonstrates that the dominant small eye phenotype is the result of separate gain-of-function mutations in the closely linked muscle segment homeobox (msh) gene, encoding a homeodomain transcription factor required for patterning of muscle and nervous system. Reversion of the Dr(Mio) allele was coincident with the generation of lethal loss-of-function mutations in msh in cis, suggesting that the dominant eye phenotype is the result of ectopic expression. Molecular genetic analysis revealed that two dominant Dr alleles contain lesions upstream of the msh transcription start site. In the Dr(Mio) mutant, a 3S18 retrotransposon insertion is the target of second-site mutations (P-element insertions or deletions) which suppress the dominant eye phenotype following reversion. The pattern of 3S18 expression and the absence of msh in eye imaginal discs suggest that transcriptional activation of the msh promoter accounts for ectopic expression. Dr dominant mutations arrest eye development by blocking the progression of the morphogenetic furrow leading to photoreceptor cell loss via apoptosis. Gal4-mediated ubiquitous expression of msh in third-instar larvae was sufficient to arrest the morphogenetic furrow in the eye imaginal disc and resulted in lethality prior to eclosion. Dominant mutations in the human msx2 gene, one of the vertebrate homologs of msh, are associated with craniosynostosis, a disease affecting cranial development. The Dr mutations are the first example of gain-of-function mutations in the msh/msx gene family identified in a genetically tractible model organism and may serve as a useful tool to identify additional genes that regulate this class of homeodomain proteins. Copyright 2001 Academic Press.

  8. Recurring dominant-negative mutations in the AVP-NPII gene cause neurohypophyseal diabetes insipidus

    Energy Technology Data Exchange (ETDEWEB)

    Repaske, D.R. [Children`s Hospital Medical Center, Cincinnati, OH (United States); Phillips, J.A.; Krishnamani, M.R.S. [Vanderbilt Univ. School of Medicine, Nashville, TN (United States)] [and others

    1994-09-01

    Autosomal dominant neurohypophyseal diabetes insipidus (ADNDI) is a familial form of arginine vasopressin (or antidiuretic hormone) deficiency that is usually manifest in early childhood with polyuria, polydipsia and an antidiuretic response to exogenous vasopressin or its analogs. The phenotype is postulated to arise from gliosis and depletion of the magnocellular neurons that produce vasopressin in the supraoptic and paraventricular nuclei of the hypothalamus. ADNDI is caused by heterozygosity for a variety of mutations in the AVP-NPII gene which encodes vasopressin, its carrier protein (NPII) and a glycoprotein (copeptin) of unknown function. These mutations include: (1) Ala 19{r_arrow}Thr (G279A) in AVP`s signal peptide, (2) Gly 17{r_arrow}Val (G1740T), (3) Pro 24{r_arrow}Leu (C1761T), (4) Gly 57{r_arrow}Ser (G1859A) and (5) del Glu 47({delta}AGG 1824-26), all of which occur in NPII. In characterizing the AVP-NPII mutations in five non-related ADNDI kindreds, we have detected two kindreds having mutation 1 (G279A), two having mutation 3 (C1761T) and one having mutation 4 (G1859A) without any other allelic changes being detected. Two of these recurring mutations (G279A and G1859A) are transitions that occur at CpG dinucleotides while the third (C1761T) does not. Interestingly, families with the same mutations differed in their ethnicity or in their affected AVP-NPII allele`s associated haplotype of closely linked DNA polymorphisms. Our data indicated that at least three of five known AVP-NPII mutations causing ADNDI tend to recur but the mechanisms by which these dominant-negative mutations cause variable or progressive expression of the ADNDI phenotype remain unclear.

  9. Mutation rate estimation for 15 autosomal STR loci in a large population from Mainland China.

    Science.gov (United States)

    Zhao, Zhuo; Zhang, Jie; Wang, Hua; Liu, Zhi-Peng; Liu, Ming; Zhang, Yuan; Sun, Li; Zhang, Hui

    2015-09-01

    STR, short tandem repeats, are well known as a type of powerful genetic marker and widely used in studying human population genetics. Compared with the conventional genetic markers, the mutation rate of STR is higher. Additionally, the mutations of STR loci do not lead to genetic inconsistencies between the genotypes of parents and children; therefore, the analysis of STR mutation is more suited to assess the population mutation. In this study, we focused on 15 autosomal STR loci. DNA samples from a total of 42,416 unrelated healthy individuals (19,037 trios) from the population of Mainland China collected between Jan 2012 and May 2014 were successfully investigated. In our study, the allele frequencies, paternal mutation rates, maternal mutation rates and average mutation rates were detected. Furthermore, we also investigated the relationship between paternal ages, maternal ages, area, the time of pregnancy and average mutation rate. We found that the paternal mutation rate was higher than the maternal mutation rate and the paternal, maternal, and average mutation rates had a positive correlation with paternal age, maternal age and the time of pregnancy respectively. Additionally, the average mutation rate of coastal areas was higher than that of inland areas.

  10. The Impact of Collisions on the Ability to Detect Rare Mutant Alleles Using Barcode-Type Next-Generation Sequencing Techniques

    Directory of Open Access Journals (Sweden)

    Jenna VanLiere Canzoniero

    2017-07-01

    Full Text Available Barcoding techniques are used to reduce error from next-generation sequencing, with applications ranging from understanding tumor subclone populations to detecting circulating tumor DNA. Collisions occur when more than one sample molecule is tagged by the same unique identifier (UID and can result in failure to detect very-low-frequency mutations and error in estimating mutation frequency. Here, we created computer models of barcoding technique, with and without amplification bias introduced by the UID, and analyzed the effect of collisions for a range of mutant allele frequencies (1e−6 to 0.2, number of sample molecules (10 000 to 1e7, and number of UIDs (4 10 -4 14 . Inability to detect rare mutant alleles occurred in 0% to 100% of simulations, depending on collisions and number of mutant molecules. Collisions also introduced error in estimating mutant allele frequency resulting in underestimation of minor allele frequency. Incorporating an understanding of the effect of collisions into experimental design can allow for optimization of the number of sample molecules and number of UIDs to minimize the negative impact on rare mutant detection and mutant frequency estimation.

  11. Deletion mutations of bacteriophage

    International Nuclear Information System (INIS)

    Ryo, Yeikou

    1975-01-01

    Resolution of mutation mechanism with structural changes of DNA was discussed through the studies using bacteriophage lambda. One of deletion mutations inductions of phage lambda is the irradiation of ultraviolet ray. It is not clear if the inductions are caused by errors in reparation of ultraviolet-induced damage or by the activation of int gene. Because the effective site of int gene lies within the regions unnecessary for existing, it is considered that int gene is connected to deletion mutations induction. A certain system using prophage complementarity enables to detect deletion mutations at essential hereditary sites and to solve the relations of deletion mutations with other recombination system, DNA reproduction and repairment system. Duplication and multiplication of hereditary elements were discussed. If lambda deletion mutations of the system, which can control recombination, reproduction and repairment of added DNA, are constructed, mutations mechanism with great changes of DNA structure can be solved by phage lambda. (Ichikawa, K.)

  12. Soft sweeps III: the signature of positive selection from recurrent mutation.

    Directory of Open Access Journals (Sweden)

    Pleuni S Pennings

    2006-12-01

    Full Text Available Polymorphism data can be used to identify loci at which a beneficial allele has recently gone to fixation, given that an accurate description of the signature of selection is available. In the classical model that is used, a favored allele derives from a single mutational origin. This ignores the fact that beneficial alleles can enter a population recurrently by mutation during the selective phase. In this study, we present a combination of analytical and simulation results to demonstrate the effect of adaptation from recurrent mutation on summary statistics for polymorphism data from a linked neutral locus. We also analyze the power of standard neutrality tests based on the frequency spectrum or on linkage disequilibrium (LD under this scenario. For recurrent beneficial mutation at biologically realistic rates, we find substantial deviations from the classical pattern of a selective sweep from a single new mutation. Deviations from neutrality in the level of polymorphism and in the frequency spectrum are much less pronounced than in the classical sweep pattern. In contrast, for levels of LD, the signature is even stronger if recurrent beneficial mutation plays a role. We suggest a variant of existing LD tests that increases their power to detect this signature.

  13. More about the Viking hypothesis of origin of the delta32 mutation in the CCR5 gene conferring resistance to HIV-1 infection.

    Science.gov (United States)

    Lucotte, Gérard; Dieterlen, Florent

    2003-11-01

    The chemokine receptor CCR5 constitutes the major coreceptor for the HIV-1, because a mutant allele of the CCR5 gene named delta32 was shown to provide to homozygotes a strong resistance against infection. In the present study the frequency of the delta32 allele was collected in 36 European populations and in Cyprus, and the highest allele frequencies were found in Nordic countries. We constructed an allele map of delta32 frequencies in Europe; the map is in accordance to the Vikings hypothesis of the origin of the mutation and his dissemination during the eighth to the tenth centuries.

  14. Role of heterozygous APC mutation in niche succession and initiation of colorectal cancer--a computational study.

    Directory of Open Access Journals (Sweden)

    Roschen Sasikumar

    Full Text Available Mutations in the adenomatous polyposis coli (APC gene are found in most colorectal cancers. They cause constitutive activation of proliferative pathways when both alleles of the gene are mutated. However studies on individuals with familial adenomatous polyposis (FAP have shown that a single mutated APC allele can also create changes in the precancerous colon crypt, like increased number of stem cells, increased crypt fission, greater variability of DNA methylation patterns, and higher somatic mutation rates. In this paper, using a computational model of colon crypt dynamics, we evolve and investigate a hypothesis on the effect of heterozygous APC mutation that explains these different observations. Based on previous reports and the results from the computational model we propose the hypothesis that heterozygous APC mutation has the effect of increasing the chances for a stem cell to divide symmetrically, producing two stem cell daughters. We incorporate this hypothesis into the model and perform simulation experiments to investigate the consequences of the hypothesis. Simulations show that this hypothesis links together the changes in FAP crypts observed in previous studies. The simulations also show that an APC(+/- stem cell gets selective advantages for dominating the crypt and progressing to cancer. This explains why most colon cancers are initiated by APC mutation. The results could have implications for preventing or retarding the onset of colon cancer in people with inherited or acquired mutation of one APC allele. Experimental validation of the hypothesis as well as investigation into the molecular mechanisms of this effect may therefore be worth undertaking.

  15. Paternal or Maternal Uniparental Disomy of Chromosome 16 Resulting in Homozygosity of a Mutant Allele Causes Fanconi Anemia.

    Science.gov (United States)

    Donovan, Frank X; Kimble, Danielle C; Kim, Yonghwan; Lach, Francis P; Harper, Ursula; Kamat, Aparna; Jones, MaryPat; Sanborn, Erica M; Tryon, Rebecca; Wagner, John E; MacMillan, Margaret L; Ostrander, Elaine A; Auerbach, Arleen D; Smogorzewska, Agata; Chandrasekharappa, Settara C

    2016-05-01

    Fanconi anemia (FA) is a rare inherited disorder caused by pathogenic variants in one of 19 FANC genes. FA patients display congenital abnormalities, and develop bone marrow failure, and cancer susceptibility. We identified homozygous mutations in four FA patients and, in each case, only one parent carried the obligate mutant allele. FANCA and FANCP/SLX4 genes, both located on chromosome 16, were the affected recessive FA genes in three and one family respectively. Genotyping with short tandem repeat markers and SNP arrays revealed uniparental disomy (UPD) of the entire mutation-carrying chromosome 16 in all four patients. One FANCA patient had paternal UPD, whereas FA in the other three patients resulted from maternal UPD. These are the first reported cases of UPD as a cause of FA. UPD indicates a reduced risk of having another child with FA in the family and has implications in prenatal diagnosis. © 2016 WILEY PERIODICALS, INC.

  16. Selected missense mutations impair frataxin processing in Friedreich ataxia.

    Science.gov (United States)

    Clark, Elisia; Butler, Jill S; Isaacs, Charles J; Napierala, Marek; Lynch, David R

    2017-08-01

    Frataxin (FXN) is a highly conserved mitochondrial protein. Reduced FXN levels cause Friedreich ataxia, a recessive neurodegenerative disease. Typical patients carry GAA repeat expansions on both alleles, while a subgroup of patients carry a missense mutation on one allele and a GAA repeat expansion on the other. Here, we report that selected disease-related FXN missense mutations impair FXN localization, interaction with mitochondria processing peptidase, and processing. Immunocytochemical studies and subcellular fractionation were performed to study FXN import into the mitochondria and examine the mechanism by which mutations impair FXN processing. Coimmunoprecipitation was performed to study the interaction between FXN and mitochondrial processing peptidase. A proteasome inhibitor was used to model traditional therapeutic strategies. In addition, clinical profiles of subjects with and without point mutations were compared in a large natural history study. FXN I 154F and FXN G 130V missense mutations decrease FXN 81-210 levels compared with FXN WT , FXN R 165C , and FXN W 155R , but do not block its association with mitochondria. FXN I 154F and FXN G 130V also impair FXN maturation and enhance the binding between FXN 42-210 and mitochondria processing peptidase. Furthermore, blocking proteosomal degradation does not increase FXN 81-210 levels. Additionally, impaired FXN processing also occurs in fibroblasts from patients with FXN G 130V . Finally, clinical data from patients with FXN G 130V and FXN I 154F mutations demonstrates a lower severity compared with other individuals with Friedreich ataxia. These data suggest that the effects on processing associated with FXN G 130V and FXN I 154F mutations lead to higher levels of partially processed FXN, which may contribute to the milder clinical phenotypes in these patients.

  17. A naturally occurring mutation in ropB suppresses SpeB expression and reduces M1T1 group A streptococcal systemic virulence.

    Directory of Open Access Journals (Sweden)

    Andrew Hollands

    Full Text Available Epidemiological studies of group A streptococcus (GAS have noted an inverse relationship between SpeB expression and invasive disease. However, the role of SpeB in the course of infection is still unclear. In this study we utilize a SpeB-negative M1T1 clinical isolate, 5628, with a naturally occurring mutation in the gene encoding the regulator RopB, to elucidate the role of RopB and SpeB in systemic virulence. Allelic exchange mutagenesis was used to replace the mutated ropB allele in 5628 with the intact allele from the well characterized isolate 5448. The inverse allelic exchange was also performed to replace the intact ropB in 5448 with the mutated allele from 5628. An intact ropB was found to be essential for SpeB expression. While the ropB mutation was shown to have no effect on hemolysis of RBC's, extracellular DNase activity or survival in the presence of neutrophils, strains with the mutated ropB allele were less virulent in murine systemic models of infection. An isogenic SpeB knockout strain containing an intact RopB showed similarly reduced virulence. Microarray analysis found genes of the SpeB operon to be the primary target of RopB regulation. These data show that an intact RopB and efficient SpeB production are necessary for systemic infection with GAS.

  18. Detecting imbalanced expression of SNP alleles by minisequencing on microarrays

    Directory of Open Access Journals (Sweden)

    Dahlgren Andreas

    2004-10-01

    Full Text Available Abstract Background Each of the human genes or transcriptional units is likely to contain single nucleotide polymorphisms that may give rise to sequence variation between individuals and tissues on the level of RNA. Based on recent studies, differential expression of the two alleles of heterozygous coding single nucleotide polymorphisms (SNPs may be frequent for human genes. Methods with high accuracy to be used in a high throughput setting are needed for systematic surveys of expressed sequence variation. In this study we evaluated two formats of multiplexed, microarray based minisequencing for quantitative detection of imbalanced expression of SNP alleles. We used a panel of ten SNPs located in five genes known to be expressed in two endothelial cell lines as our model system. Results The accuracy and sensitivity of quantitative detection of allelic imbalance was assessed for each SNP by constructing regression lines using a dilution series of mixed samples from individuals of different genotype. Accurate quantification of SNP alleles by both assay formats was evidenced for by R2 values > 0.95 for the majority of the regression lines. According to a two sample t-test, we were able to distinguish 1–9% of a minority SNP allele from a homozygous genotype, with larger variation between SNPs than between assay formats. Six of the SNPs, heterozygous in either of the two cell lines, were genotyped in RNA extracted from the endothelial cells. The coefficient of variation between the fluorescent signals from five parallel reactions was similar for cDNA and genomic DNA. The fluorescence signal intensity ratios measured in the cDNA samples were compared to those in genomic DNA to determine the relative expression levels of the two alleles of each SNP. Four of the six SNPs tested displayed a higher than 1.4-fold difference in allelic ratios between cDNA and genomic DNA. The results were verified by allele-specific oligonucleotide hybridisation and

  19. Improved multiplex ligation-dependent probe amplification analysis identifies a deleterious PMS2 allele generated by recombination with crossover between PMS2 and PMS2CL.

    Science.gov (United States)

    Wernstedt, Annekatrin; Valtorta, Emanuele; Armelao, Franco; Togni, Roberto; Girlando, Salvatore; Baudis, Michael; Heinimann, Karl; Messiaen, Ludwine; Staehli, Noemie; Zschocke, Johannes; Marra, Giancarlo; Wimmer, Katharina

    2012-09-01

    Heterozygous PMS2 germline mutations are associated with Lynch syndrome. Up to one third of these mutations are genomic deletions. Their detection is complicated by a pseudogene (PMS2CL), which--owing to extensive interparalog sequence exchange--closely resembles PMS2 downstream of exon 12. A recently redesigned multiplex ligation-dependent probe amplification (MLPA) assay identifies PMS2 copy number alterations with improved reliability when used with reference DNAs containing equal numbers of PMS2- and PMS2CL-specific sequences. We selected eight such reference samples--all publicly available--and used them with this assay to study 13 patients with PMS2-defective colorectal tumors. Three presented deleterious alterations: an Alu-mediated exon deletion; a 125-kb deletion encompassing PMS2 and four additional genes (two with tumor-suppressing functions); and a novel deleterious hybrid PMS2 allele produced by recombination with crossover between PMS2 and PMS2CL, with the breakpoint in intron 10 (the most 5' breakpoint of its kind reported thus far). We discuss mechanisms that might generate this allele in different chromosomal configurations (and their diagnostic implications) and describe an allele-specific PCR assay that facilitates its detection. Our data indicate that the redesigned PMS2 MLPA assay is a valid first-line option. In our series, it identified roughly a quarter of all PMS2 mutations. Copyright © 2012 Wiley Periodicals, Inc.

  20. Screening for duplications, deletions and a common intronic mutation detects 35% of second mutations in patients with USH2A monoallelic mutations on Sanger sequencing.

    Science.gov (United States)

    Steele-Stallard, Heather B; Le Quesne Stabej, Polona; Lenassi, Eva; Luxon, Linda M; Claustres, Mireille; Roux, Anne-Francoise; Webster, Andrew R; Bitner-Glindzicz, Maria

    2013-08-08

    Usher Syndrome is the leading cause of inherited deaf-blindness. It is divided into three subtypes, of which the most common is Usher type 2, and the USH2A gene accounts for 75-80% of cases. Despite recent sequencing strategies, in our cohort a significant proportion of individuals with Usher type 2 have just one heterozygous disease-causing mutation in USH2A, or no convincing disease-causing mutations across nine Usher genes. The purpose of this study was to improve the molecular diagnosis in these families by screening USH2A for duplications, heterozygous deletions and a common pathogenic deep intronic variant USH2A: c.7595-2144A>G. Forty-nine Usher type 2 or atypical Usher families who had missing mutations (mono-allelic USH2A or no mutations following Sanger sequencing of nine Usher genes) were screened for duplications/deletions using the USH2A SALSA MLPA reagent kit (MRC-Holland). Identification of USH2A: c.7595-2144A>G was achieved by Sanger sequencing. Mutations were confirmed by a combination of reverse transcription PCR using RNA extracted from nasal epithelial cells or fibroblasts, and by array comparative genomic hybridisation with sequencing across the genomic breakpoints. Eight mutations were identified in 23 Usher type 2 families (35%) with one previously identified heterozygous disease-causing mutation in USH2A. These consisted of five heterozygous deletions, one duplication, and two heterozygous instances of the pathogenic variant USH2A: c.7595-2144A>G. No variants were found in the 15 Usher type 2 families with no previously identified disease-causing mutations. In 11 atypical families, none of whom had any previously identified convincing disease-causing mutations, the mutation USH2A: c.7595-2144A>G was identified in a heterozygous state in one family. All five deletions and the heterozygous duplication we report here are novel. This is the first time that a duplication in USH2A has been reported as a cause of Usher syndrome. We found that 8 of

  1. Drop-out probabilities of IrisPlex SNP alleles

    DEFF Research Database (Denmark)

    Andersen, Jeppe Dyrberg; Tvedebrink, Torben; Mogensen, Helle Smidt

    2013-01-01

    In certain crime cases, information about a perpetrator's phenotype, including eye colour, may be a valuable tool if no DNA profile of any suspect or individual in the DNA database matches the DNA profile found at the crime scene. Often, the available DNA material is sparse and allelic drop-out...... of true alleles is possible. As part of the validation of the IrisPlex assay in our ISO17025 accredited, forensic genetic laboratory, we estimated the probability of drop-out of specific SNP alleles using 29 and 30 PCR cycles and 25, 50 and 100 Single Base Extension (SBE) cycles. We observed no drop-out...... when the amount of DNA was greater than 125 pg for 29 cycles of PCR and greater than 62 pg for 30 cycles of PCR. With the use of a logistic regression model, we estimated the allele specific probability of drop-out in heterozygote systems based on the signal strength of the observed allele...

  2. Common breast cancer risk alleles and risk assessment

    DEFF Research Database (Denmark)

    Näslund-Koch, C; Nordestgaard, B G; Bojesen, S E

    2017-01-01

    general population were followed in Danish health registries for up to 21 years after blood sampling. After genotyping 72 breast cancer risk loci, each with 0-2 alleles, the sum for each individual was calculated. We used the simple allele sum instead of the conventional polygenic risk score......, as it is likely more sensitive in detecting associations with risks of other endpoints than breast cancer. RESULTS: Breast cancer incidence in the 19,010 women was increased across allele sum quintiles (log-rank trend test; p=1*10(-12)), but not incidence of other cancers (p=0.41). Age- and study-adjusted hazard...... ratio for the 5(th) vs. 1(st) allele sum quintile was 1.82(95% confidence interval;1.53-2.18). Corresponding hazard ratios per allele were 1.04(1.03-1.05) and 1.05(1.02-1.08) for breast cancer incidence and mortality, similar across risk factors. In 50-year old women, the starting age for screening...

  3. Recurrent vomiting and ethylmalonic aciduria associated with rare mutations in the short-chain acyl-CoA dehydrogenase (SCAD) gene

    DEFF Research Database (Denmark)

    Seidel, J.; Streck, S.; Bellstedt, K.

    2003-01-01

    blood spots. Neither of the frequent SCAD gene variants 625G>A and 511C>T was present, but direct sequencing of the promoter and coding regions of the SCAD gene revealed that the patient had mutations on both alleles: 417G>C (Trpl15Cys) and 1095G>T (Gln341His). Neither mutation has been described before...

  4. Novel mutations and mutation combinations of ryanodine receptor in a chlorantraniliprole resistant population of Plutella xylostella (L.)

    Science.gov (United States)

    Guo, Lei; Liang, Pei; Zhou, Xuguo; Gao, Xiwu

    2014-01-01

    A previous study documented a glycine to glutamic acid mutation (G4946E) in ryanodine receptor (RyR) was highly correlated to diamide insecticide resistance in field populations of Plutella xylostella (Lepidoptera: Plutellidae). In this study, a field population collected in Yunnan province, China, exhibited a 2128-fold resistance to chlorantraniliprole. Sequence comparison between resistant and susceptible P. xylostella revealed three novel mutations including a glutamic acid to valine substitution (E1338D), a glutamine to leucine substitution (Q4594L) and an isoleucine to methionine substitution (I4790M) in highly conserved regions of RyR. Frequency analysis of all four mutations in this field population showed that the three new mutations showed a high frequency of 100%, while the G4946E had a frequency of 20%. Furthermore, the florescent ligand binding assay revealed that the RyR containing multiple mutations displayed a significantly lower affinity to the chlorantraniliprole. The combined results suggested that the co-existence of different combinations of the four mutations was involved in the chlorantraniliprole resistance. An allele-specific PCR based method was developed for the diagnosis of the four mutations in the field populations of P. xylostella. PMID:25377064

  5. High Frequency of Alkaptonuria in Slovakia: Evidence for the Appearance of Multiple Mutations in HGO Involving Different Mutational Hot Spots

    Science.gov (United States)

    Zatková, Andrea; de Bernabé, Daniel Beltrán Valero; Poláková, Helena; Zvarík, Marek; Feráková, Eva; Bošák, Vladimir; Ferák, Vladimír; Kádasi, L'udovít; de Córdoba , Santiago Rodríguez

    2000-01-01

    Alkaptonuria (AKU) is an autosomal recessive disorder caused by the deficiency of homogentisate 1,2 dioxygenase (HGO) activity. AKU shows a very low prevalence (1:100,000–250,000) in most ethnic groups. One notable exception is in Slovakia, where the incidence of AKU rises to 1:19,000. This high incidence is difficult to explain by a classical founder effect, because as many as 10 different AKU mutations have been identified in this relatively small country. We have determined the allelic associations of 11 HGO intragenic polymorphisms for 44 AKU chromosomes from 20 Slovak pedigrees. These data were compared to the HGO haplotype data available in our laboratory for >80 AKU chromosomes from different European and non-European countries. The results show that common European AKU chromosomes have had only a marginal contribution to the Slovak AKU gene pool. Six of the ten Slovak AKU mutations, including the prevalent G152fs, G161R, G270R, and P370fs mutations, most likely originated in Slovakia. Data available for 17 Slovak AKU pedigrees indicate that most of the AKU chromosomes have their origins in a single very small region in the Carpathian mountains, in the northwestern part of the country. Since all six Slovak AKU mutations are associated with HGO mutational hot spots, we suggest that an increased mutation rate at the HGO gene is responsible for the clustering of AKU mutations in such a small geographical region. PMID:11017803

  6. Parkinson's disease-related LRRK2 G2019S mutation results from independent mutational events in humans.

    Science.gov (United States)

    Lesage, Suzanne; Patin, Etienne; Condroyer, Christel; Leutenegger, Anne-Louise; Lohmann, Ebba; Giladi, Nir; Bar-Shira, Anat; Belarbi, Soraya; Hecham, Nassima; Pollak, Pierre; Ouvrard-Hernandez, Anne-Marie; Bardien, Soraya; Carr, Jonathan; Benhassine, Traki; Tomiyama, Hiroyuki; Pirkevi, Caroline; Hamadouche, Tarik; Cazeneuve, Cécile; Basak, A Nazli; Hattori, Nobutaka; Dürr, Alexandra; Tazir, Meriem; Orr-Urtreger, Avi; Quintana-Murci, Lluis; Brice, Alexis

    2010-05-15

    Mutations in the leucine-rich-repeat kinase 2 (LRRK2) gene have been identified in families with autosomal dominant Parkinson's disease (PD) and in sporadic cases; the G2019S mutation is the single most frequent. Intriguingly, the frequency of this mutation in PD patients varies greatly among ethnic groups and geographic origins: it is present at <0.1% in East Asia, approximately 2% in European-descent patients and can reach frequencies of up to 15-40% in PD Ashkenazi Jews and North African Arabs. To ascertain the evolutionary dynamics of the G2019S mutation in different populations, we genotyped 74 markers spanning a 16 Mb genomic region around G2019S, in 191 individuals carrying the mutation from 126 families of different origins. Sixty-seven families were of North-African Arab origin, 18 were of North/Western European descent, 37 were of Jewish origin, mostly from Eastern Europe, one was from Japan, one from Turkey and two were of mixed origins. We found the G2019S mutation on three different haplotypes. Network analyses of the three carrier haplotypes showed that G2019S arose independently at least twice in humans. In addition, the population distribution of the intra-allelic diversity of the most widespread carrier haplotype, together with estimations of the age of G2019S determined by two different methods, suggests that one of the founding G2019S mutational events occurred in the Near East at least 4000 years ago.

  7. Determination of frequencies of alleles, associated with the pseudodeficiency of lysosomal hydrolases, in population of Ukraine.

    Science.gov (United States)

    Olkhovych, N V; Gorovenko, N G

    2016-01-01

    The pseudodeficiency of lysosomal hydrolases described as a significant reduction in enzyme activi­ty in vitro in clinically healthy individuals, can lead to diagnostic errors in the process of biochemical analysis of lysosomal storage disease in case of its combination with pathology of another origin. Pseudodeficiency is mostly caused by some non-pathogenic changes in the corresponding gene. These changes lead to the in vitro lability of the enzyme molecule, whereas in vivo the enzyme retains its functional activity. To assess the prevalence of the most common lysosomal hydrolases pseudodeficiency alleles in Ukraine, we have determined the frequency of alleles c.1055A>G and c.* 96A>G in the ARSA gene, substitutions c.739C>T (R247W) and c.745C>T (R249W) in the HEXA gene, c.1726G>A (G576S) and c.2065G>A (E689K) in the GAA gene, c.937G>T (D313Y) in the GLA1 gene and c.898G>A (A300T) in the IDUA gene in a group of 117 healthy individuals from different regions of the country and 14 heterozygous carriers of pathogenic mutations in the HEXA gene (parents of children with confirmed diagnosis of Tay-Sachs disease). The total frequency of haplotypes, associated with arylsulfatase A pseudodeficiency, in healthy people in Ukraine (c.1055G/c.*96G and c.1055G/c.*96A haplotypes) was 10.3%. The frequency of c.739C>T (R247W) allele, associated with hexo­saminidase A pseudodeficiency, among Tay-Sachs carriers from Ukraine was 7.1%. The total frequency of α-glucosidase pseudodeficiency haplotypes in healthy individuals in Ukraine (c.1726A/c.2065A and c.1726G/c.2065A haplotypes) was 2.6%. No person among examined individuals with the substitution c.937G>T (D313Y) in the GLA1 gene and c.898G>A (A300T) in the IDUA gene was found. The differential diagnostics of lysosomal storage diseases requires obligatory determination of the presence of the pseudodeficiency alleles, particularly the ones with high incidence in the total population. Ignoring phenomenon of pseudodeficiency may

  8. Determination of frequencies of alleles, associated with the pseudodeficiency of lysosomal hydrolases, in population of Ukraine

    Directory of Open Access Journals (Sweden)

    N. V. Olkhovych

    2016-10-01

    Full Text Available The pseudodeficiency of lysosomal hydrolases described as a significant reduction in enzyme activi­ty in vitro in clinically healthy individuals, can lead to diagnostic errors in the process of biochemical analysis of lysosomal storage disease in case of its combination with pathology of another origin. Pseudodeficiency is mostly caused by some non-pathogenic changes in the corresponding gene. These changes lead to the in vitro lability of the enzyme molecule, whereas in vivo the enzyme retains its functional activity. To assess the prevalence of the most common lysosomal hydrolases pseudodeficiency alleles in Ukraine, we have determined the frequency of alleles c.1055A>G and c.* 96A>G in the ARSA gene, substitutions c.739C>T (R247W and c.745C>T (R249W in the HEXA gene, c.1726G>A (G576S and c.2065G>A (E689K in the GAA gene, c.937G>T (D313Y in the GLA1 gene and c.898G>A (A300T in the IDUA gene in a group of 117 healthy individuals from different regions of the country and 14 heterozygous carriers of pathogenic mutations in the HEXA gene (parents of children with confirmed diagnosis of Tay-Sachs disease. The total frequency of haplotypes, associated with arylsulfatase A pseudodeficiency, in healthy people in Ukraine (c.1055G/c.*96G and c.1055G/c.*96A haplotypes was 10.3%. The frequency of c.739C>T (R247W allele, associated with hexo­saminidase A pseudodeficiency, among Tay-Sachs carriers from Ukraine was 7.1%. The total frequency of α-glucosidase pseudodeficiency haplotypes in healthy individuals in Ukraine (c.1726A/c.2065A and c.1726G/c.2065A haplotypes was 2.6%. No person among examined individuals with the substitution c.937G>T (D313Y in the GLA1 gene and c.898G>A (A300T in the IDUA gene was found. The differential diagnostics of lysosomal storage diseases requires obligatory determination of the presence of the pseudodeficiency alleles, particularly the ones with high incidence in the total population. Ignoring phenomenon of

  9. Detecting differential allelic expression using high-resolution melting curve analysis: application to the breast cancer susceptibility gene CHEK2

    Directory of Open Access Journals (Sweden)

    Sinilnikova Olga

    2011-05-01

    Full Text Available Abstract Background The gene CHEK2 encodes a checkpoint kinase playing a key role in the DNA damage pathway. Though CHEK2 has been identified as an intermediate breast cancer susceptibility gene, only a small proportion of high-risk families have been explained by genetic variants located in its coding region. Alteration in gene expression regulation provides a potential mechanism for generating disease susceptibility. The detection of differential allelic expression (DAE represents a sensitive assay to direct the search for a functional sequence variant within the transcriptional regulatory elements of a candidate gene. We aimed to assess whether CHEK2 was subject to DAE in lymphoblastoid cell lines (LCLs from high-risk breast cancer patients for whom no mutation in BRCA1 or BRCA2 had been identified. Methods We implemented an assay based on high-resolution melting (HRM curve analysis and developed an analysis tool for DAE assessment. Results We observed allelic expression imbalance in 4 of the 41 LCLs examined. All four were carriers of the truncating mutation 1100delC. We confirmed previous findings that this mutation induces non-sense mediated mRNA decay. In our series, we ruled out the possibility of a functional sequence variant located in the promoter region or in a regulatory element of CHEK2 that would lead to DAE in the transcriptional regulatory milieu of freely proliferating LCLs. Conclusions Our results support that HRM is a sensitive and accurate method for DAE assessment. This approach would be of great interest for high-throughput mutation screening projects aiming to identify genes carrying functional regulatory polymorphisms.

  10. The presence of two different infantile Tay-Sachs disease mutations in a Cajun population

    Energy Technology Data Exchange (ETDEWEB)

    McDowell, G.A.; Blitzer, M.G. (Univ. of Maryland School of Medicine, Baltimore, MD (United States)); Mules, E.H. (Kennedy Krieger Institute, Baltimore, MD (United States)); Fabacher, P. (Office of Public Health, Shreveport, LA (United States)); Shapira, E. (Tulane Univ. of School of Medicine, New Orleans, LA (United States))

    1992-11-01

    A study was undertaken to characterize the mutation(s) responsible for Tay-Sachs disease (TSD) in a Cajun population in southwest Louisiana and to identify the origins of these mutations. Eleven of 12 infantile TSD alleles examined in six families had the [beta]-hexosaminidase A (Hex A) [alpha]-subunit exon 11 insertion mutation that is present in approximately 70% of Ashkenazi Jewish TSD heterozygotes. The mutation in the remaining allele was a single-base transition in the donor splice site of the [alpha]-subunit intron 9. To determine the origins of these two mutations in the Cajun population, the TSD carrier status was enzymatically determined for 90 members of four of the six families, and extensive pedigrees were constructed for all carriers. A single ancestral couple from France was found to be common to most of the carriers of the exon 11 insertion. Pedigree data suggest that this mutation has been in the Cajun population since its founding over 2 centuries ago and that it may be widely distributed within the population. In contrast, the intron 9 mutation apparently was introduced within the last century and probably is limited to a few Louisiana families. 29 refs., 4 figs.

  11. Outcome of ABCA4 disease-associated alleles in autosomal recessive retinal dystrophies: retrospective analysis in 420 Spanish families.

    Science.gov (United States)

    Riveiro-Alvarez, Rosa; Lopez-Martinez, Miguel-Angel; Zernant, Jana; Aguirre-Lamban, Jana; Cantalapiedra, Diego; Avila-Fernandez, Almudena; Gimenez, Ascension; Lopez-Molina, Maria-Isabel; Garcia-Sandoval, Blanca; Blanco-Kelly, Fiona; Corton, Marta; Tatu, Sorina; Fernandez-San Jose, Patricia; Trujillo-Tiebas, Maria-Jose; Ramos, Carmen; Allikmets, Rando; Ayuso, Carmen

    2013-11-01

    To provide a comprehensive overview of all detected mutations in the ABCA4 gene in Spanish families with autosomal recessive retinal disorders, including Stargardt's disease (arSTGD), cone-rod dystrophy (arCRD), and retinitis pigmentosa (arRP), and to assess genotype-phenotype correlation and disease progression in 10 years by considering the type of variants and age at onset. Case series. A total of 420 unrelated Spanish families: 259 arSTGD, 86 arCRD, and 75 arRP. Spanish families were analyzed through a combination of ABCR400 genotyping microarray, denaturing high-performance liquid chromatography, and high-resolution melting scanning. Direct sequencing was used as a confirmation technique for the identified variants. Screening by multiple ligation probe analysis was used to detect possible large deletions or insertions in the ABCA4 gene. Selected families were analyzed further by next generation sequencing. DNA sequence variants, mutation detection rates, haplotypes, age at onset, central or peripheral vision loss, and night blindness. Overall, we detected 70.5% and 36.6% of all expected ABCA4 mutations in arSTGD and arCRD patient cohorts, respectively. In the fraction of the cohort where the ABCA4 gene was sequenced completely, the detection rates reached 73.6% for arSTGD and 66.7% for arCRD. However, the frequency of possibly pathogenic ABCA4 alleles in arRP families was only slightly higher than that in the general population. Moreover, in some families, mutations in other known arRP genes segregated with the disease phenotype. An increasing understanding of causal ABCA4 alleles in arSTGD and arCRD facilitates disease diagnosis and prognosis and also is paramount in selecting patients for emerging clinical trials of therapeutic interventions. Because ABCA4-associated diseases are evolving retinal dystrophies, assessment of age at onset, accurate clinical diagnosis, and genetic testing are crucial. We suggest that ABCA4 mutations may be associated with a

  12. An evolutionary reduction principle for mutation rates at multiple Loci.

    Science.gov (United States)

    Altenberg, Lee

    2011-06-01

    A model of mutation rate evolution for multiple loci under arbitrary selection is analyzed. Results are obtained using techniques from Karlin (Evolutionary Biology, vol. 14, pp. 61-204, 1982) that overcome the weak selection constraints needed for tractability in prior studies of multilocus event models.A multivariate form of the reduction principle is found: reduction results at individual loci combine topologically to produce a surface of mutation rate alterations that are neutral for a new modifier allele. New mutation rates survive if and only if they fall below this surface-a generalization of the hyperplane found by Zhivotovsky et al. (Proc. Natl. Acad. Sci. USA 91, 1079-1083, 1994) for a multilocus recombination modifier. Increases in mutation rates at some loci may evolve if compensated for by decreases at other loci. The strength of selection on the modifier scales in proportion to the number of germline cell divisions, and increases with the number of loci affected. Loci that do not make a difference to marginal fitnesses at equilibrium are not subject to the reduction principle, and under fine tuning of mutation rates would be expected to have higher mutation rates than loci in mutation-selection balance.Other results include the nonexistence of 'viability analogous, Hardy-Weinberg' modifier polymorphisms under multiplicative mutation, and the sufficiency of average transmission rates to encapsulate the effect of modifier polymorphisms on the transmission of loci under selection. A conjecture is offered regarding situations, like recombination in the presence of mutation, that exhibit departures from the reduction principle. Constraints for tractability are: tight linkage of all loci, initial fixation at the modifier locus, and mutation distributions comprising transition probabilities of reversible Markov chains.

  13. Prevalence of carriers of premutation-size alleles of the FMR1 gene-and implications for the population genetics of the fragile X syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Rousseau, F.; Rouillard, P.; Morel, M.L. [Universite Laval, Quebec City (Canada)] [and others

    1995-11-01

    The fragile X syndrome is the second leading cause of mental retardation after Down syndrome. Fragile X premutations are not associated with any clinical phenotype but are at high risk of expanding to full mutations causing the disease when they are transmitted by a carrier woman. There is no reliable estimate of the prevalence of women who are carriers of fragile X premutations. We have screened 10,624 unselected women by Southern blot for the presence of FMR1 premutation alleles and have confirmed their size by PCR analysis. We found 41 carriers of alleles with 55-101 CGG repeats, a prevalence of 1/259 women (95% confidence interval 1/373-1/198). Thirty percent of these alleles carry an inferred haplotype that corresponds to the most frequent haplotype found in fragile X males and may indeed constitute premutations associated with a significant risk of expansion on transmission by carrier women. We identified another inferred haplotype that is rare in both normal and fragile X chromosomes but that is present on 13 (57%) of 23 chromosomes carrying FMR1 alleles with 53-64 CGG repeats. This suggests either (1) that this haplotype may be stable or (2) that the associated premutation-size alleles have not yet reached equilibrium in this population and that the incidence of fragile X syndrome may increase in the future. 42 refs., 3 figs., 4 tabs.

  14. Linkage disequilibrium between an allele at the dopamine D4 receptor locus and Tourette syndrome, by the transmission-disequilibrium test

    Energy Technology Data Exchange (ETDEWEB)

    Grice, D.E.; Gelernter, J. [Veterans Administration Connecticut Healthcare System, West Haven, CT (United States); Leckman, J.F.; Pauls, D.L. [Yale Univ. School of Medicine, New Haven, CT (United States)] [and others

    1996-09-01

    Dopaminergic abnormalities are implicated in the pathogenesis of Tourette syndrome (TS) and chronic multiple tics. We used the transmission-disequilibrium test (TDT) method to test for linkage disequilibrium between a specific allele (the seven-repeat allele (DRD4*7R) of the exon 3 VNTR polymorphic site) at the D4 dopamine receptor locus (DRD4) and expression of chronic multiple tics and TS. This particular allele had been shown in functional studies to have different binding properties compared with the other common alleles in this DRD4 polymorphic system. We studied 64 family trios (consisting of an affected person and two parents, at least one heterozygous for DRD4*7R), including 12 nuclear family trios and 52 trios from four large TS kindreds. The DRD4*7R allele was transmitted significantly more frequently than expected ({chi}{sup 2}{sub TDT} ranging from 8.47 [P < .004] to 10.80 [P = .001], depending on breadth of disease definition and inclusion or exclusion of inferred genotypes). Confirmation of this finding will depend on either replication in other samples or the identification of a transmitted functional mutation within this sample. 56 refs., 2 figs., 3 tabs.

  15. Mutations in MDH2, Encoding a Krebs Cycle Enzyme, Cause Early-Onset Severe Encephalopathy

    NARCIS (Netherlands)

    Ait-El-Mkadem, Samira; Dayem-Quere, Manal; Gusic, Mirjana; Chaussenot, Annabelle; Bannwarth, Sylvie; François, Bérengère; Genin, Emmanuelle C; Fragaki, Konstantina; Volker-Touw, Catharina L M; Vasnier, Christelle; Serre, Valérie; van Gassen, Koen L I; Lespinasse, Françoise; Richter, Susan; Eisenhofer, Graeme; Rouzier, Cécile; Mochel, Fanny; De Saint-Martin, Anne; Abi Warde, Marie-Thérèse; de Sain-van der Velden, Monique G M; Jans, Judith J M; Amiel, Jeanne; Avsec, Ziga; Mertes, Christian; Haack, Tobias B; Strom, Tim; Meitinger, Thomas; Bonnen, Penelope E; Taylor, Robert W; Gagneur, Julien; van Hasselt, Peter M; Rötig, Agnès; Delahodde, Agnès; Prokisch, Holger; Fuchs, Sabine A; Paquis-Flucklinger, Véronique

    2016-01-01

    MDH2 encodes mitochondrial malate dehydrogenase (MDH), which is essential for the conversion of malate to oxaloacetate as part of the proper functioning of the Krebs cycle. We report bi-allelic pathogenic mutations in MDH2 in three unrelated subjects presenting with early-onset generalized

  16. Association between a specific apolipoprotein B mutation and familial defective apolipoprotein B-100

    International Nuclear Information System (INIS)

    Soria, L.F.; Ludwig, E.H.; Clarke, H.R.G.; McCarthy, B.J.; Vega, G.L.; Grundy, S.M.

    1989-01-01

    Familial defective apolipoprotein (apo) B-100 is a genetic disease that leads to hypercholesterolemia and to an increased serum concentration of low density lipoproteins that bind defectively to the apoB,E(LDL) receptor. The disorder appears to result from a mutation in the gene for apoB-100. Extensive sequence analysis of the two alleles of one subject heterozygous for the disorder has revealed a previously unreported mutation in the codon for amino acid 3500 that results in the substitution of glutamine for arginine. This same mutant allele occurs in six other, unrelated subjects and in eight affected relatives in two of these families. A partial haplotype of this mutant apoB-100 allele was constructed by sequence analysis and restriction enzyme digestion at positions where variations in the apoB-100 are known to occur. This haplotype is the same in three probands and four affected members of one family and lacks a polymorphic Xba I site whose presence has been correlated with high cholesterol levels. Thus, it appears that the mutation in the codon for amino acid 3500 (CGG → CAG), a CG mutational hot spot, defines a minor apoB-100 allele associated with defective low density lipoproteins and hypercholesterolemia

  17. Alpha-tubulin missense mutations correlate with antimicrotubule drug resistance in Eleusine indica.

    Science.gov (United States)

    Yamamoto, E; Zeng, L; Baird, W V

    1998-02-01

    Dinitroaniline herbicides are antimicrotubule drugs that bind to tubulins and inhibit polymerization. As a result of repeated application of dinitroaniline herbicides, highly resistant and intermediately resistant biotypes of goosegrass (Eleusine indica) developed in previously wild-type populations. Three alpha-tubulin cDNA classes (designated TUA1, TUA2, and TUA3) were isolated from each biotype. Nucleotide differences between the susceptible and the resistant (R) alpha-tubulins were identified in TUA1 and TUA2. The most significant differences were missense mutations that occurred in TUA1 of the R and intermediately resistant (I) biotypes. Such mutations convert Thr-239 to Ile in the R biotype and Met-268 to Thr in the I biotype. These amino acid substitutions alter hydrophobicity; therefore, they may alter the dinitroaniline binding property of the protein. These mutations were correlated with the dinitroaniline response phenotypes (Drp). Plants homozygous for susceptibility possessed the wild-type TUA1 allele; plants homozygous for resistance possessed the mutant tua1 allele; and plants heterozygous for susceptibility possessed both wild-type and mutant alleles. Thus, we conclude that TUA1 is at the Drp locus. Using polymerase chain reaction primer-introduced restriction analysis, we demonstrated that goosegrass genomic DNA can be diagnosed for Drp alleles. Although not direct proof, these results suggest that a mutation in an alpha-tubulin gene confers resistance to dinitroanilines in goosegrass.

  18. Changes in mutational status during third-line treatment for metastatic colorectal cancer

    DEFF Research Database (Denmark)

    Spindler, Karen-Lise Garm; Pallisgaard, Niels; Andersen, Rikke Fredslund

    2014-01-01

    and BRAF in plasma and report the changes during third line treatment with cetuximab and irinotecan. One-hundred-and-eight patients received irinotecan 350 mg/m2 q3w and weekly cetuximab (250 mg/m2) until progression (RECIST) or unacceptable toxicity. cfDNA and number of mutated KRAS/BRAF alleles in plasma...

  19. Polymorphisms and mutations of human TMPRSS6 in iron deficiency anemia.

    NARCIS (Netherlands)

    Beutler, E.; Geet, C. Van; Loo, D.M.W.M. te; Gelbart, T.; Crain, K.; Truksa, J.; Lee, P.L.

    2010-01-01

    Male subjects with iron deficiency from the general population were examined for polymorphisms or sporadic mutations in TMPRSS6 to identify genetic risk factors for iron deficiency anemia. Three uncommon non-synonymous polymorphisms were identified, G228D, R446W, and V795I (allele frequencies

  20. MAP2K1 and MAP3K1 mutations in langerhans cell histiocytosis

    NARCIS (Netherlands)

    Nelson, David S.; van Halteren, Astrid; Quispel, Willemijn T.; van den Bos, Cor; Bovée, Judith V. M. G.; Patel, Bhumi; Badalian-Very, Gayane; van Hummelen, Paul; Ducar, Matthew; Lin, Ling; MacConaill, Laura E.; Egeler, R. Maarten; Rollins, Barrett J.

    2015-01-01

    Langerhans cell histiocytosis (LCH) is now understood to be a neoplastic disease in which over 50% of cases have somatic activating mutations of BRAF. However, the extracellular signal-related (ERK) pathway is activated in all cases including those with wild type BRAF alleles. Here, we applied a

  1. Implication of HLA-DMA Alleles in Corsican IDDM

    Directory of Open Access Journals (Sweden)

    P. Cucchi-Mouillot

    1998-01-01

    Full Text Available The HLA-DM molecule catalyses the CLIP/antigen peptide exchange in the classical class II peptide-binding groove. As such, DM is an antigen presentation regulator and may be linked to autoimmune diseases. Using PCR derived methods, a relationship was revealed between DM gene polymorphism and IDDM, in a Corsican population. The DMA*0101 allele was observed to confer a significant predisposition to this autoimmune disease while the DMA*0102 allele protected significantly. Experiments examining polymorphism of the HLA-DRB1 gene established that these relationships are not a consequence of linkage disequilibrium with HLA-DRB1 alleles implicated in this pathology. The study of the DMA gene could therefore be an additional tool for early IDDM diagnosis in the Corsican population.

  2. Automated analysis of high-throughput B-cell sequencing data reveals a high frequency of novel immunoglobulin V gene segment alleles.

    Science.gov (United States)

    Gadala-Maria, Daniel; Yaari, Gur; Uduman, Mohamed; Kleinstein, Steven H

    2015-02-24

    Individual variation in germline and expressed B-cell immunoglobulin (Ig) repertoires has been associated with aging, disease susceptibility, and differential response to infection and vaccination. Repertoire properties can now be studied at large-scale through next-generation sequencing of rearranged Ig genes. Accurate analysis of these repertoire-sequencing (Rep-Seq) data requires identifying the germline variable (V), diversity (D), and joining (J) gene segments used by each Ig sequence. Current V(D)J assignment methods work by aligning sequences to a database of known germline V(D)J segment alleles. However, existing databases are likely to be incomplete and novel polymorphisms are hard to differentiate from the frequent occurrence of somatic hypermutations in Ig sequences. Here we develop a Tool for Ig Genotype Elucidation via Rep-Seq (TIgGER). TIgGER analyzes mutation patterns in Rep-Seq data to identify novel V segment alleles, and also constructs a personalized germline database containing the specific set of alleles carried by a subject. This information is then used to improve the initial V segment assignments from existing tools, like IMGT/HighV-QUEST. The application of TIgGER to Rep-Seq data from seven subjects identified 11 novel V segment alleles, including at least one in every subject examined. These novel alleles constituted 13% of the total number of unique alleles in these subjects, and impacted 3% of V(D)J segment assignments. These results reinforce the highly polymorphic nature of human Ig V genes, and suggest that many novel alleles remain to be discovered. The integration of TIgGER into Rep-Seq processing pipelines will increase the accuracy of V segment assignments, thus improving B-cell repertoire analyses.

  3. Population differentiation in allele frequencies of obesity-associated SNPs.

    Science.gov (United States)

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

    2017-11-10

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

  4. Novel cytochrome P450 (CYP6D1) and voltage sensitive sodium channel (Vssc) alleles of the house fly (Musca domestica) and their roles in pyrethroid resistance.

    Science.gov (United States)

    Pan, Jing; Yang, Chan; Liu, Yan; Gao, Qi; Li, Mei; Qiu, Xinghui

    2018-04-01

    The house fly Musca domestica is an important disease vector. Point mutation-mediated target-site insensitivity of the voltage sensitive sodium channel (VSSC) and increased detoxification mediated by cytochrome P450 (CYP6D1) overexpression have been characterized as two major mechanisms of pyrethroid resistance. In this study, genetic mutations in the Vssc and CYP6D1 genes and their contribution to pyrethroid resistance were investigated. Twelve lines of house flies homozygous for four genotypes were established. House flies carrying the VSSC 1014F mutation and overexpressing CYP6D1 had higher resistance to pyrethroids than those carrying 1014F alone. The presence of the 15-bp insert in the promoter region of the CYP6D1 gene did not necessarily result in a significant increase in CYP6D1 mRNA and pyrethroid resistance levels. A novel Vssc allele carrying two mutations (G1924D and G2004S) in combination with the classic 1014F and a novel CYP6D1 allele that is very similar to CYP6D1v1 were identified in Chinese house flies. This work demonstrates the effect of genetic mutations in CYP6D1 and Vssc on the susceptibility of house flies to pyrethroids, and verifies that 15-bp insert-containing CYP6D1 alleles have a single origin. These findings offer insights into the evolution of insecticide resistance and have implications for house fly control. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  5. Targeted next-generation sequencing extends the phenotypic and mutational spectrums for EYS mutations.

    Science.gov (United States)

    Gu, Shun; Tian, Yuanyuan; Chen, Xue; Zhao, Chen

    2016-01-01

    We aim to determine genetic lesions with a phenotypic correlation in four Chinese families with autosomal recessive retinitis pigmentosa (RP). Medical histories were carefully reviewed. All patients received comprehensive ophthalmic evaluations. The next-generation sequencing (NGS) approach targeting a panel of 205 retinal disease-relevant genes and 15 candidate genes was selectively performed on probands from the four recruited families for mutation detection. Online predictive software and crystal structure modeling were also applied to test the potential pathogenic effects of identified mutations. Of the four families, two were diagnosed with RP sino pigmento (RPSP). Patients with RPSP claimed to have earlier RP age of onset but slower disease progression. Five mutations in the eyes shut homolog (EYS) gene, involving two novel (c.7228+1G>A and c.9248G>A) and three recurrent mutations (c.4957dupA, c.6416G>A and c.6557G>A), were found as RP causative in the four families. The missense variant c.5093T>C was determined to be a variant of unknown significance (VUS) due to the variant's colocalization in the same allele with the reported pathogenic mutation c.6416G>A. The two novel variants were further confirmed absent in 100 unrelated healthy controls. Online predictive software indicated potential pathogenicity of the three missense mutations. Further, crystal structural modeling suggested generation of two abnormal hydrogen bonds by the missense mutation p.G2186E (c.6557G>A) and elongation of its neighboring β-sheet induced by p.G3083D (c.9248G>A), which could alter the tertiary structure of the eys protein and thus interrupt its physicochemical properties. Taken together, with the targeted NGS approach, we reveal novel EYS mutations and prove the efficiency of targeted NGS in the genetic diagnoses of RP. We also first report the correlation between EYS mutations and RPSP. The genotypic-phenotypic relationship in all Chinese patients carrying mutations in the EYS

  6. High frequency of mutation G377S in Brazilian type 3 Gaucher disease patients

    Directory of Open Access Journals (Sweden)

    R. Rozenberg

    2006-09-01

    Full Text Available Gaucher disease (GD, the most prevalent lysosome storage disorder, presents an autosomal recessive mode of inheritance. It is a paradigm for therapeutic intervention in medical genetics due to the existence of effective enzyme replacement therapy. We report here the analysis of GD in 262 unrelated Brazilian patients, carried out in order to establish the frequency of the most common mutations and to provide prognostic information based on genotype-phenotype correlations. Among 247 type 1 GD patients, mutation N370S was detected in 47% of all the alleles, but N370S/N370S homozygosity was found in only 10% of the patients, a much lower frequency than expected, suggesting that most individuals presenting this genotype may not receive medical attention. Recombinant alleles were detected at a high frequency: 44% of the chromosomes bearing mutation L444P had other mutations derived from the pseudogene sequence, present in 25% of patients. Three neuronopathic type 2 patients were homozygous for L444P, all presenting additional mutations (E326K or recombinant alleles that probably lead to the more severe phenotypes. Six children, classified as type 1 GD patients, had a L444P/L444P genotype, showing that neuronopathic symptoms may only manifest later in life. This would indicate the need for a higher treatment dose during enzyme replacement therapy. Finally, mutation G377S was present in 4 homozygous type 1 patients and also in compound heterozygosity in 5 (42% type 3 patients. These findings indicate that G377S cannot be unambiguously classified as mild and suggest an allele-dose effect for this mutation.

  7. Reduced Height (Rht Alleles Affect Wheat Grain Quality.

    Directory of Open Access Journals (Sweden)

    Richard Casebow

    Full Text Available The effects of dwarfing alleles (reduced height, Rht in near isogenic lines on wheat grain quality are characterised in field experiments and related to effects on crop height, grain yield and GA-sensitivity. Alleles included those that conferred GA-insensitivity (Rht-B1b, Rht-B1c, Rht-D1b, Rht-D1c as well as those that retained GA-sensitivity (rht(tall, Rht8, Rht8 + Ppd-D1a, Rht12. Full characterisation was facilitated by including factors with which the effects of Rht alleles are known to interact for grain yield (i.e. system, [conventional or organic]; tillage intensity [plough-based, minimum or zero]; nitrogen fertilizer level [0-450 kg N/ha]; and genetic backgrounds varying in height [cvs Maris Huntsman, Maris Widgeon, and Mercia]. Allele effects on mean grain weight and grain specific weight were positively associated with final crop height: dwarfing reduced these quality criteria irrespective of crop management or GA-sensitivity. In all but two experiments the effects of dwarfing alleles on grain nitrogen and sulphur concentrations were closely and negatively related to effects on grain yield, e.g. a quadratic relationship between grain yield and crop height manipulated by the GA-insensitive alleles was mirrored by quadratic relationships for nitrogen and sulphur concentrations: the highest yields and most dilute concentrations occurred around 80cm. In one of the two exceptional experiments the GA-insensitive Rht-B1b and Rht-B1c significantly (P<0.05 reduced grain nitrogen concentration in the absence of an effect on yield, and in the remaining experiment the GA-sensitive Rht8 significantly reduced both grain yield and grain nitrogen concentration simultaneously. When Rht alleles diluted grain nitrogen concentration, N:S ratios and SDS-sedimentation volumes were often improved. Hagberg falling number (HFN was negatively related to crop height but benefits from dwarfing were only seen for GA-insensitive alleles. For HFN, therefore, there

  8. Reduced Height (Rht) Alleles Affect Wheat Grain Quality.

    Science.gov (United States)

    Casebow, Richard; Hadley, Caroline; Uppal, Rajneet; Addisu, Molla; Loddo, Stefano; Kowalski, Ania; Griffiths, Simon; Gooding, Mike

    2016-01-01

    The effects of dwarfing alleles (reduced height, Rht) in near isogenic lines on wheat grain quality are characterised in field experiments and related to effects on crop height, grain yield and GA-sensitivity. Alleles included those that conferred GA-insensitivity (Rht-B1b, Rht-B1c, Rht-D1b, Rht-D1c) as well as those that retained GA-sensitivity (rht(tall), Rht8, Rht8 + Ppd-D1a, Rht12). Full characterisation was facilitated by including factors with which the effects of Rht alleles are known to interact for grain yield (i.e. system, [conventional or organic]; tillage intensity [plough-based, minimum or zero]; nitrogen fertilizer level [0-450 kg N/ha]; and genetic backgrounds varying in height [cvs Maris Huntsman, Maris Widgeon, and Mercia]. Allele effects on mean grain weight and grain specific weight were positively associated with final crop height: dwarfing reduced these quality criteria irrespective of crop management or GA-sensitivity. In all but two experiments the effects of dwarfing alleles on grain nitrogen and sulphur concentrations were closely and negatively related to effects on grain yield, e.g. a quadratic relationship between grain yield and crop height manipulated by the GA-insensitive alleles was mirrored by quadratic relationships for nitrogen and sulphur concentrations: the highest yields and most dilute concentrations occurred around 80cm. In one of the two exceptional experiments the GA-insensitive Rht-B1b and Rht-B1c significantly (Pgrain nitrogen concentration in the absence of an effect on yield, and in the remaining experiment the GA-sensitive Rht8 significantly reduced both grain yield and grain nitrogen concentration simultaneously. When Rht alleles diluted grain nitrogen concentration, N:S ratios and SDS-sedimentation volumes were often improved. Hagberg falling number (HFN) was negatively related to crop height but benefits from dwarfing were only seen for GA-insensitive alleles. For HFN, therefore, there was the strongest evidence for

  9. A common allele on chromosome 9 associated with coronary heartdisease

    Energy Technology Data Exchange (ETDEWEB)

    McPherson, Ruth; Pertsemlidis, Alexander; Kavaslar, Nihan; Stewart, Alexandre; Roberts, Robert; Cox, David R.; Hinds, David; Pennachio, Len; Tybjaerg-Hansen, Anne; Folsom, Aaron R.; Boerwinkle,Eric; Hobbs, Helen H.; Cohen, Jonathan C.

    2007-03-01

    Coronary heart disease (CHD) is a major cause of death in Western countries. Here we used genome-wide association scanning to identify a 58 kb interval on chromosome 9 that was consistently associated with CHD in six independent samples. The interval contains no annotated genes and is not associated with established CHD risk factors such as plasma lipoproteins, hypertension or diabetes. Homozygotes for the risk allele comprise 20-25% of Caucasians and have a {approx}30-40% increased risk of CHD. These data indicate that the susceptibility allele acts through a novel mechanism to increase CHD risk in a large fraction of the population.

  10. Mutant alleles of FAD2-1A and FAD2-1B combine to produce soybeans with the high oleic acid seed oil trait

    Directory of Open Access Journals (Sweden)

    Pham Anh-Tung

    2010-09-01

    Full Text Available Abstract Background The alteration of fatty acid profiles in soybean [Glycine max (L. Merr.] to improve soybean oil quality is an important and evolving theme in soybean research to meet nutritional needs and industrial criteria in the modern market. Soybean oil with elevated oleic acid is desirable because this monounsaturated fatty acid improves the nutrition and oxidative stability of the oil. Commodity soybean oil typically contains 20% oleic acid and the target for high oleic acid soybean oil is approximately 80% of the oil; previous conventional plant breeding research to raise the oleic acid level to just 50-60% of the oil was hindered by the genetic complexity and environmental instability of the trait. The objective of this work was to create the high oleic acid trait in soybeans by identifying and combining mutations in two delta-twelve fatty acid desaturase genes, FAD2-1A and FAD2-1B. Results Three polymorphisms found in the FAD2-1B alleles of two soybean lines resulted in missense mutations. For each of the two soybean lines, there was one unique amino acid change within a highly conserved region of the protein. The mutant FAD2-1B alleles were associated with an increase in oleic acid levels, although the FAD2-1B mutant alleles alone were not capable of producing a high oleic acid phenotype. When existing FAD2-1A mutations were combined with the novel mutant FAD2-1B alleles, a high oleic acid phenotype was recovered only for those lines which were homozygous for both of the mutant alleles. Conclusions We were able to produce conventional soybean lines with 80% oleic acid in the oil in two different ways, each requiring the contribution of only two genes. The high oleic acid soybean germplasm developed contained a desirable fatty acid profile, and it was stable in two production environments. The presumed causative sequence polymorphisms in the FAD2-1B alleles were developed into highly efficient molecular markers for tracking the

  11. Mutant alleles of FAD2-1A and FAD2-1B combine to produce soybeans with the high oleic acid seed oil trait.

    Science.gov (United States)

    Pham, Anh-Tung; Lee, Jeong-Dong; Shannon, J Grover; Bilyeu, Kristin D

    2010-09-09

    The alteration of fatty acid profiles in soybean [Glycine max (L.) Merr.] to improve soybean oil quality is an important and evolving theme in soybean research to meet nutritional needs and industrial criteria in the modern market. Soybean oil with elevated oleic acid is desirable because this monounsaturated fatty acid improves the nutrition and oxidative stability of the oil. Commodity soybean oil typically contains 20% oleic acid and the target for high oleic acid soybean oil is approximately 80% of the oil; previous conventional plant breeding research to raise the oleic acid level to just 50-60% of the oil was hindered by the genetic complexity and environmental instability of the trait. The objective of this work was to create the high oleic acid trait in soybeans by identifying and combining mutations in two delta-twelve fatty acid desaturase genes, FAD2-1A and FAD2-1B. Three polymorphisms found in the FAD2-1B alleles of two soybean lines resulted in missense mutations. For each of the two soybean lines, there was one unique amino acid change within a highly conserved region of the protein. The mutant FAD2-1B alleles were associated with an increase in oleic acid levels, although the FAD2-1B mutant alleles alone were not capable of producing a high oleic acid phenotype. When existing FAD2-1A mutations were combined with the novel mutant FAD2-1B alleles, a high oleic acid phenotype was recovered only for those lines which were homozygous for both of the mutant alleles. We were able to produce conventional soybean lines with 80% oleic acid in the oil in two different ways, each requiring the contribution of only two genes. The high oleic acid soybean germplasm developed contained a desirable fatty acid profile, and it was stable in two production environments. The presumed causative sequence polymorphisms in the FAD2-1B alleles were developed into highly efficient molecular markers for tracking the mutant alleles. The resources described here for the creation

  12. The C allele of JAK2 rs4495487 is an additional candidate locus that contributes to myeloproliferative neoplasm predisposition in the Japanese population

    Directory of Open Access Journals (Sweden)

    Ohyashiki Junko H

    2012-01-01

    Full Text Available Abstract Background Polycythemia vera (PV, essential thrombocythemia (ET, and primary myelofibrosis (PMF are myeloproliferative neoplasms (MPNs characterized in most cases by a unique somatic mutation, JAK2 V617F. Recent studies revealed that JAK2 V617F occurs more frequently in a specific JAK2 haplotype, named JAK2 46/1 or GGCC haplotype, which is tagged by rs10974944 (C/G and/or rs12343867 (T/C. This study examined the impact of single nucleotide polymorphisms (SNPs of the JAK2 locus on MPNs in a Japanese population. Methods We sequenced 24 JAK2 SNPs in Japanese patients with PV. We then genotyped 138 MPN patients (33 PV, 96 ET, and 9 PMF with known JAK2 mutational status and 107 controls for a novel SNP, in addition to two SNPs known to be part of the 46/1 haplotype (rs10974944 and rs12343867. Associations with risk of MPN were estimated by odds ratios and their 95% confidence intervals using logistic regression. Results A novel locus, rs4495487 (T/C, with a mutated T allele was significantly associated with PV. Similar to rs10974944 and rs12343867, rs4495487 in the JAK2 locus is significantly associated with JAK2-positive MPN. Based on the results of SNP analysis of the three JAK2 locus, we defined the "GCC genotype" as having at least one minor allele in each SNP (G allele in rs10974944, C allele in rs4495487, and C allele in rs12343867. The GCC genotype was associated with increased risk of both JAK2 V617F-positive and JAK2 V617F-negative MPN. In ET patients, leukocyte count and hemoglobin were significantly associated with JAK2 V617F, rather than the GCC genotype. In contrast, none of the JAK2 V617F-negative ET patients without the GCC genotype had thrombosis, and splenomegaly was frequently seen in this subset of ET patients. PV patients without the GCC genotype were significantly associated with high platelet count. Conclusions Our results indicate that the C allele of JAK2 rs4495487, in addition to the 46/1 haplotype, contributes

  13. Clinical relevance of IDH1/2 mutant allele burden during follow-up in acute myeloid leukemia. A study by the French ALFA group

    Science.gov (United States)

    Ferret, Yann; Boissel, Nicolas; Helevaut, Nathalie; Madic, Jordan; Nibourel, Olivier; Marceau-Renaut, Alice; Bucci, Maxime; Geffroy, Sandrine; Celli-Lebras, Karine; Castaigne, Sylvie; Thomas, Xavier; Terré, Christine; Dombret, Hervé; Preudhomme, Claude; Renneville, Aline

    2018-01-01

    Assessment of minimal residual disease has emerged as a powerful prognostic factor in acute myeloid leukemia. In this study, we investigated the potential of IDH1/2 mutations as targets for minimal residual disease assessment in acute myeloid leukemia, since these mutations collectively occur in 15–20% of cases of acute myeloid leukemia and now represent druggable targets. We employed droplet digital polymerase chain reaction assays to quantify IDH1R132, IDH2R140, and IDH2R172 mutations on genomic DNA in 322 samples from 103 adult patients with primary IDH1/2 mutant acute myeloid leukemia and enrolled on Acute Leukemia French Association (ALFA) - 0701 or -0702 clinical trials. The median IDH1/2 mutant allele fraction in bone marrow samples was 42.3% (range, 8.2 – 49.9%) at diagnosis of acute myeloid leukemia, and below the detection limit of 0.2% (range, <0.2 – 39.3%) in complete remission after induction therapy. In univariate analysis, the presence of a normal karyotype, a NPM1 mutation, and an IDH1/2 mutant allele fraction <0.2% in bone marrow after induction therapy were statistically significant predictors of longer disease-free survival. In multivariate analysis, these three variables remained significantly predictive of disease-free survival. In 7/103 (7%) patients, IDH1/2 mutations persisted at high levels in complete remission, consistent with the presence of an IDH1/2 mutation in pre-leukemic hematopoietic stem cells. Five out of these seven patients subsequently relapsed or progressed toward myelodysplastic syndrome, suggesting that patients carrying the IDH1/2 mutation in a pre-leukemic clone may be at high risk of hematologic evolution. PMID:29472349

  14. Mutations in myosin VIIA (MYO7A) and usherin (USH2A) in Spanish patients with Usher syndrome types I and II, respectively.

    Science.gov (United States)

    Nájera, Carmen; Beneyto, Magdalena; Blanca, José; Aller, Elena; Fontcuberta, Ana; Millán, José María; Ayuso, Carmen

    2002-07-01

    Usher syndrome is an autosomal recessive disorder characterized by congenital hearing impairment and retinitis pigmentosa. Three clinical types are known (USH1, USH2 and USH3), and there is an extensive genetic heterogeneity, with at least ten genes implicated. The most frequently mutated genes are MYO7A, which causes USH1B, and usherin, which causes USH2A. We carried out a mutation analysis of these two genes in the Spanish population. Analysis of the MYO7A gene in patients from 30 USH1 families and sporadic cases identified 32% of disease alleles, with mutation Q821X being the most frequent. Most of the remaining variants are private mutations. With regard to USH2, mutation 2299delG was detected in 25% of the Spanish patients. Altogether the mutations detected in USH2A families account for 23% of the disease alleles. Copyright 2002 Wiley-Liss, Inc.

  15. CFTR mutations spectrum and the efficiency of molecular diagnostics in Polish cystic fibrosis patients.

    Directory of Open Access Journals (Sweden)

    Ewa Ziętkiewicz

    Full Text Available Cystic fibrosis (CF is caused by mutations in the cystic fibrosis transmembrane regulator gene (CFTR. In light of the strong allelic heterogeneity and regional specificity of the mutation spectrum, the strategy of molecular diagnostics and counseling in CF requires genetic tests to reflect the frequency profile characteristic for a given population. The goal of the study was to provide an updated comprehensive estimation of the distribution of CFTR mutations in Polish CF patients and to assess the effectiveness of INNOLiPA_CFTR tests in Polish population. The analyzed cohort consisted of 738 patients with the clinically confirmed CF diagnosis, prescreened for molecular defects using INNOLiPA_CFTR panels from Innogenetics. A combined efficiency of INNOLiPA CFTR_19 and CFTR_17_TnUpdate tests was 75.5%; both mutations were detected in 68.2%, and one mutation in 14.8% of the affected individuals. The group composed of all the patients with only one or with no mutation detected (109 and 126 individuals, respectively was analyzed further using a mutation screening approach, i.e. SSCP/HD (single strand conformational polymorphism/heteroduplex analysis of PCR products followed by sequencing of the coding sequence. As a result, 53 more mutations were found in 97 patients. The overall efficiency of the CF allele detection was 82.5% (7.0% increase compared to INNOLiPA tests alone. The distribution of the most frequent mutations in Poland was assessed. Most of the mutations repetitively found in Polish patients had been previously described in other European populations. The most frequent mutated allele, F508del, represented 54.5% of Polish CF chromosomes. Another eight mutations had frequencies over 1%, 24 had frequencies between 1 and 0.1%; c.2052-2053insA and c.3468+2_3468+3insT were the most frequent non-INNOLiPA mutations. Mutation distribution described herein is also relevant to the Polish diaspora. Our study also demonstrates that the reported

  16. A dominantly acting murine allele of Mcm4 causes chromosomal abnormalities and promotes tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Bruce N Bagley

    Full Text Available Here we report the isolation of a murine model for heritable T cell lymphoblastic leukemia/lymphoma (T-ALL called Spontaneous dominant leukemia (Sdl. Sdl heterozygous mice develop disease with a short latency and high penetrance, while mice homozygous for the mutation die early during embryonic development. Sdl mice exhibit an increase in the frequency of micronucleated reticulocytes, and T-ALLs from Sdl mice harbor small amplifications and deletions, including activating deletions at the Notch1 locus. Using exome sequencing it was determined that Sdl mice harbor a spontaneously acquired mutation in Mcm4 (Mcm4(D573H. MCM4 is part of the heterohexameric complex of MCM2-7 that is important for licensing of DNA origins prior to S phase and also serves as the core of the replicative helicase that unwinds DNA at replication forks. Previous studies in murine models have discovered that genetic reductions of MCM complex levels promote tumor formation by causing genomic instability. However, Sdl mice possess normal levels of Mcms, and there is no evidence for loss-of-heterozygosity at the Mcm4 locus in Sdl leukemias. Studies in Saccharomyces cerevisiae indicate that the Sdl mutation produces a biologically inactive helicase. Together, these data support a model in which chromosomal abnormalities in Sdl mice result from the ability of MCM4(D573H to incorporate into MCM complexes and render them inactive. Our studies indicate that dominantly acting alleles of MCMs can be compatible with viability but have dramatic oncogenic consequences by causing chromosomal abnormalities.

  17. A dominantly acting murine allele of Mcm4 causes chromosomal abnormalities and promotes tumorigenesis.

    Science.gov (United States)

    Bagley, Bruce N; Keane, Thomas M; Maklakova, Vilena I; Marshall, Jonathon G; Lester, Rachael A; Cancel, Michelle M; Paulsen, Alex R; Bendzick, Laura E; Been, Raha A; Kogan, Scott C; Cormier, Robert T; Kendziorski, Christina; Adams, David J; Collier, Lara S

    2012-01-01

    Here we report the isolation of a murine model for heritable T cell lymphoblastic leukemia/lymphoma (T-ALL) called Spontaneous dominant leukemia (Sdl). Sdl heterozygous mice develop disease with a short latency and high penetrance, while mice homozygous for the mutation die early during embryonic development. Sdl mice exhibit an increase in the frequency of micronucleated reticulocytes, and T-ALLs from Sdl mice harbor small amplifications and deletions, including activating deletions at the Notch1 locus. Using exome sequencing it was determined that Sdl mice harbor a spontaneously acquired mutation in Mcm4 (Mcm4(D573H)). MCM4 is part of the heterohexameric complex of MCM2-7 that is important for licensing of DNA origins prior to S phase and also serves as the core of the replicative helicase that unwinds DNA at replication forks. Previous studies in murine models have discovered that genetic reductions of MCM complex levels promote tumor formation by causing genomic instability. However, Sdl mice possess normal levels of Mcms, and there is no evidence for loss-of-heterozygosity at the Mcm4 locus in Sdl leukemias. Studies in Saccharomyces cerevisiae indicate that the Sdl mutation produces a biologically inactive helicase. Together, these data support a model in which chromosomal abnormalities in Sdl mice result from the ability of MCM4(D573H) to incorporate into MCM complexes and render them inactive. Our studies indicate that dominantly acting alleles of MCMs can be compatible with viability but have dramatic oncogenic consequences by causing chromosomal abnormalities.

  18. Ewes carrying the Booroola and Vacaria prolificacy alleles respond differently to ovulation induction with equine chorionic gonadotrophin.

    Science.gov (United States)

    Moraes, J C F; Souza, C J H

    2017-09-21

    The magnitude of ovulation rate (OR) after hormonal induction in sheep should be considered when prolific genotypes are used. We investigated for the first time the effect of the Vacaria allele and its combined effect with the Booroola prolificacy mutation on OR after hormonal treatment during breeding and anoestrous season. A hundred forty-nine Ile de France crossbred ewes, raised in natural pastures in South Brazil, were used to evaluate the OR after treatment with progestagen (MAP) followed or not by equine chorionic gonadotrophin (eCG) treatment (MAP + eCG). During the breeding season, 96% MAP-treated ewes ovulated in comparison to 97% of MAP + eCG-treated females. The double heterozygous carriers (BNVN) presented the higher OR, followed by the single Vacaria (NNVN) and Booroola (BNNN) heterozygous females and least the wild-type (NNNN) ewes. During anoestrus, 96% eCG-treated ewes ovulated, in contrast to 6% treated with MAP alone. The OR of the gonadotrophin-treated females was higher in BNVN and BNNN than NNVN and NNNN ewes. An additive effect in the OR of the two mutations was observed since OR in double heterozygous ewes was similar to the sum of the effects of the alleles of the single heterozygous carrier ewes.

  19. Better plants through mutations

    International Nuclear Information System (INIS)

    1988-01-01

    This is a public relations film describing problems associated with the genetic improvement of crop plants through induced mutations. Mutations are the ultimate source of genetic variation in plants. Mutation induction is now established as a practical tool in plant breeding. The Joint FAO/IAEA Division and the IAEA's laboratory at Seibersdorf have supported research and practical implementation of mutation breeding of both seed propagated and vegetatively propagated plants. Plant biotechnology based on in vitro culture and recombinant DNA technology will make a further significant contribution to plant breeding

  20. A nonsense mutation in FMR1 causing fragile X syndrome

    DEFF Research Database (Denmark)

    Grønskov, Karen; Brøndum-Nielsen, Karen; Dedic, Alma

    2011-01-01

    Fragile X syndrome is a common cause of inherited intellectual disability. It is caused by lack of the FMR1 gene product FMRP. The most frequent cause is the expansion of a CGG repeat located in the 5'UTR of FMR1. Alleles with 200 or more repeats become hypermethylated and transcriptionally silent....... Only few patients with intragenic point mutations in FMR1 have been reported and, currently, routine analysis of patients referred for fragile X syndrome includes solely analysis for repeat expansion and methylation status. We identified a substitution in exon 2 of FMR1, c.80C>A, causing a nonsense...... mutation p.Ser27X, in a patient with classical clinical symptoms of fragile X syndrome. The mother who carried the mutation in heterozygous form presented with mild intellectual impairment. We conclude that further studies including western blot and DNA sequence analysis of the FMR1 gene should...

  1. Mutations in new cell cycle genes that fail to complement a multiply mutant third chromosome of Drosophila.

    Science.gov (United States)

    White-Cooper, H; Carmena, M; Gonzalez, C; Glover, D M

    1996-11-01

    We have simultaneously screened for new alleles and second site mutations that fail to complement five cell cycle mutations of Drosphila carried on a single third chromosome (gnu, polo, mgr, asp, stg). Females that are either transheterozygous for scott of the antartic (scant) and polo, or homozygous for scant produce embryos that show mitotic defects. A maternal effect upon embryonic mitoses is also seen in embryos derived from females transheterozygous with helter skelter (hsk) and either mgr or asp. cleopatra (cleo), fails to complement asp but is not uncovered by a deficiency for asp. The mitotic phenotype of larvae heterozygous for cleo and the multiple mutant chromosome is similar to weak alleles of asp, but there are no defects in male meiosis. Mutations that failed to complement stg fell into two complementation groups corresponding to stg and a new gene noose. Three of the new stg alleles are early zygotic lethals, whereas the fourth is a pharate adult lethal allele that affects both mitosis and meiosis. Mutations in noose fully complement a small deficiency that removes stg, but when placed in trans to certain stg alleles, result in late lethality and mitotic abnormalities in larval brains.

  2. Modulation of allele leakiness and adaptive mutability in Escherichia ...

    Indian Academy of Sciences (India)

    It is shown that partial phenotypic suppression of two ochre mutations (argE3 and lacZU118) and an amber mutation (in argE) by sublethal concentrations of streptomycin in an rpsL+ (streptomycin-sensitive) derivative of the Escherichia coli strain AB1157 greatly enhances their adaptive mutability under selection.

  3. Identification of two HEXA mutations causing infantile-onset Tay-Sachs disease in the Persian population.

    Science.gov (United States)

    Haghighi, Alireza; Rezazadeh, Jamileh; Shadmehri, Azam Ahmadi; Haghighi, Amirreza; Kornreich, Ruth; Desnick, Robert J

    2011-09-01

    The β-hexosaminidase A (HEXA) mutations in the first reported cases of infantile Tay-Sachs disease in the Persian population were identified in two unrelated consanguineous families. The clinical diagnoses of the affected infants were confirmed by their markedly deficient levels of HEXA activity in plasma or peripheral leukocytes. The specific causative mutation in each family was determined by sequencing the HEXA alleles in both sets of related parents. Two mutations were identified: c.1A>G (p.MIV), which obliterated the initiating methionine in codon 1, and c.1177C>T (p.R393X), which predicted a termination codon or nonsense mutation.

  4. Familial isolated primary pigmented nodular adrenocortical disease associated with a novel low penetrance PRKAR1A gene splice site mutation

    DEFF Research Database (Denmark)

    Storr, Helen L; Metherell, Louise A; Dias, Renuka

    2010-01-01

    Primary pigmented nodular adrenocortical disease (PPNAD) is associated with inactivating germline protein kinase A regulatory subunit type 1-alpha (PRKAR1A) mutations and loss of heterozygosity at the 17q22-24 locus in approximately 50% patients. PRKAR1A mutations are observed in both isolated PP...... PPNAD (iPPNAD) and Carney complex (CNC). Most mutations result in a functionally null-allele and exhibit high penetrance. We genotyped members of an extended family for a novel PRKAR1A mutation and undertook detailed phenotyping for CNC in the affected individuals....

  5. Molecular analysis of carbon ion-induced mutations in Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Shikazono, Naoya; Tanaka, Atsushi; Watanabe, Hiroshi; Tano, Shigemitsu; Yokota, Yukihiko

    1998-01-01

    In order to elucidate the characteristics of the mutations induced by ion particles at the molecular level in plants, mutated loci in carbon ion-induced mutants of Arabidopsis were investigated by PCR and Southern blot analyses. In the present study, two lines of gl1 mutant and two lines of tt4 mutant were isolated after carbon ion-irradiation. Out of four mutants, one had a deletion, other two contained rearrangements, and one had a point-like mutation. From the present result, it was suggested that ion particles induced different kinds of alterations of the DNA and therefore they could produce various types of mutant alleles in plants. (author)

  6. HFE gene mutations and iron status of Brazilian blood donors.

    Science.gov (United States)

    Santos, P C J L; Cançado, R D; Terada, C T; Rostelato, S; Gonzales, I; Hirata, R D C; Hirata, M H; Chiattone, C S; Guerra-Shinohara, E M

    2010-01-01

    Mutations of the HFE and TFR2 genes have been associated with iron overload. HFE and TFR2 mutations were assessed in blood donors, and the relationship with iron status was evaluated. Subjects (N = 542) were recruited at the Hemocentro da Santa Casa de São Paulo, São Paulo, Brazil. Iron status was not influenced by HFE mutations in women and was independent of blood donation frequency. In contrast, men carrying the HFE 282CY genotype had lower total iron-binding capacity (TIBC) than HFE 282CC genotype carriers. Men who donated blood for the first time and were carriers of the HFE 282CY genotype had higher transferrin saturation values and lower TIBC concentrations than those with the homozygous wild genotype for the HFE C282Y mutation. Moreover, in this group of blood donors, carriers of HFE 63DD plus 63HD genotypes had higher serum ferritin values than those with the homozygous wild genotype for HFE H63D mutation. Multiple linear regression analysis showed that HFE 282CY leads to a 17.21% increase (P = 0.018) and a 83.65% decrease (P = 0.007) in transferrin saturation and TIBC, respectively. In addition, serum ferritin is influenced by age (3.91%, P = 0.001) and the HFE 63HD plus DD genotype (55.84%, P = 0.021). In conclusion, the HFE 282Y and 65C alleles were rare, while the HFE 63D allele was frequent in Brazilian blood donors. The HFE C282Y and H63D mutations were associated with alterations in iron status in blood donors in a gender-dependent manner.

  7. HFE gene mutations and iron status of Brazilian blood donors

    Directory of Open Access Journals (Sweden)

    P.C.J.L. Santos

    2010-01-01

    Full Text Available Mutations of the HFE and TFR2 genes have been associated with iron overload. HFE and TFR2 mutations were assessed in blood donors, and the relationship with iron status was evaluated. Subjects (N = 542 were recruited at the Hemocentro da Santa Casa de São Paulo, São Paulo, Brazil. Iron status was not influenced by HFE mutations in women and was independent of blood donation frequency. In contrast, men carrying the HFE 282CY genotype had lower total iron-binding capacity (TIBC than HFE 282CC genotype carriers. Men who donated blood for the first time and were carriers of the HFE 282CY genotype had higher transferrin saturation values and lower TIBC concentrations than those with the homozygous wild genotype for the HFE C282Y mutation. Moreover, in this group of blood donors, carriers of HFE 63DD plus 63HD genotypes had higher serum ferritin values than those with the homozygous wild genotype for HFE H63D mutation. Multiple linear regression analysis showed that HFE 282CY leads to a 17.21% increase (P = 0.018 and a 83.65% decrease (P = 0.007 in transferrin saturation and TIBC, respectively. In addition, serum ferritin is influenced by age (3.91%, P = 0.001 and the HFE 63HD plus DD genotype (55.84%, P = 0.021. In conclusion, the HFE 282Y and 65C alleles were rare, while the HFE 63D allele was frequent in Brazilian blood donors. The HFE C282Y and H63D mutations were associated with alterations in iron status in blood donors in a gender-dependent manner.

  8. Phosphorus Partitioning of Soybean Lines Containing Different Mutant Alleles of Two Soybean Seed-Specific Adenosine Triphosphate-Binding Cassette Phytic Acid Transporter Paralogs

    Directory of Open Access Journals (Sweden)

    Jason D. Gillman

    2013-03-01

    Full Text Available Seed phytate is a repository of P and minerals in soybean [ (L. Merr.] seeds that limits P and mineral bioavailability for monogastric animals (e.g., humans, swine [], and poultry [especially chicken, ] due to insufficient digestive tract phytase activity. We previously identified epistatic recessive mutations affecting two paralogous adenosine triphosphate-binding cassette phytic acid transporter genes (one a nonsense mutation in and the other a missense mutation in as the molecular genetic basis in the ethyl methanesulfonate (EMS-induced mutant low phytate soybean line M153. An additional mutant low phytate line, M766, contained one single nucleotide polymorphism within the ninth intron of the locus as well as a nonsense mutation in . The objectives of this research were to clarify the genetics underlying the low phytate phenotype in line M766 and to determine P partitioning in new combinations of mutant alleles from M766 and M153. Inheritance of nonsense alleles affecting both ( genes (one from M153 and one from M766 led to the production of viable seeds that contained transgressive reductions in total seed phytate and significantly higher levels of inorganic phosphate than has been reported for nontransgenic soybean material and will allow efficient molecular selection of soybeans with even greater reductions of phytate for improved quality soybean meal.

  9. Detecting negative selection on recurrent mutations using gene genealogy

    Science.gov (United States)

    2013-01-01

    Background Whether or not a mutant allele in a population is under selection is an important issue in population genetics, and various neutrality tests have been invented so far to detect selection. However, detection of negative selection has been notoriously difficult, partly because negatively selected alleles are usually rare in the population and have little impact on either population dynamics or the shape of the gene genealogy. Recently, through studies of genetic disorders and genome-wide analyses, many structural variations were shown to occur recurrently in the population. Such “recurrent mutations” might be revealed as deleterious by exploiting the signal of negative selection in the gene genealogy enhanced by their recurrence. Results Motivated by the above idea, we devised two new test statistics. One is the total number of mutants at a recurrently mutating locus among sampled sequences, which is tested conditionally on the number of forward mutations mapped on the sequence genealogy. The other is the size of the most common class of identical-by-descent mutants in the sample, again tested conditionally on the number of forward mutations mapped on the sequence genealogy. To examine the performance of these two tests, we simulated recurrently mutated loci each flanked by sites with neutral single nucleotide polymorphisms (SNPs), with no recombination. Using neutral recurrent mutations as null models, we attempted to detect deleterious recurrent mutations. Our analyses demonstrated high powers of our new tests under constant population size, as well as their moderate power to detect selection in expanding populations. We also devised a new maximum parsimony algorithm that, given the states of the sampled sequences at a recurrently mutating locus and an incompletely resolved genealogy, enumerates mutation histories with a minimum number of mutations while partially resolving genealogical relationships when necessary. Conclusions With their

  10. Novel HLA Class I Alleles Associated with Indian Leprosy Patients

    Directory of Open Access Journals (Sweden)

    U. Shankarkumar

    2003-01-01

    A*0101, Cw*04011, and Cw*0602 leprosy patients was observed when compared to the controls. Further haplotype A*1102-B*4006-Cw*1502 was significantly increased among the lepromatous leprosy patients when compared to the controls. It seems that HLA class I alleles play vital roles in disease association/pathogenesis with leprosy among Indians.

  11. Molecular monitoring of resistant dhfr and dhps allelic haplotypes in ...

    African Journals Online (AJOL)

    Objective: The present study assesses the frequency of resistant dhfr and dhps alleles in Morogoro-Mvomero district in south eastern Tanzania and contrast their rate of change during 17 years of SP second line use against five years of SP first line use. Methodology: Cross sectional surveys of asymptomatic infections were ...

  12. Multifragment alleles in DNA fingerprints of the parrot, Amazona ventralis

    Science.gov (United States)

    Brock, M.K.; White, B.N.

    1991-01-01

    Human DNA probes that identify variable numbers of tandem repeat loci are being used to generate DNA fingerprints in many animal and plant species. In most species the majority of the sc rable autoradiographic bands of the DNA fingerprint represent alleles from numerous unlinked loci. This study was initiated to use DNA fingerprints to determine the amount of band-sharing among captive Hispaniolan parrots (Amazona ventralis) with known genetic relationships. This would form the data base to examine DNA fingerprints of the closely related and endangered Puerto Rican parrot (A. vittata) and to estimate the degree of inbreeding in the relic population. We found by segregation analysis of the bands scored in the DNA fingerprints of the Hispaniolan parrots that there may be as few as two to five loci identified by the human 33.15 probe. Furthermore, at one locus we identified seven alleles, one of which is represented by as many as 19 cosegregating bands. It is unknown how common multiband alleles might be in natural populations, and their existence will cause problems in the assessment of relatedness by band-sharing analysis. We believe, therefore, that a pedigree analysis should be included in all DNA fingerprinting studies, where possible, in order to estimate the number of loci identified by a minisatellite DNA probe and to examine the nature of their alleles.

  13. Allele frequency distribution for 21 autosomal STR loci in Bhutan.

    Science.gov (United States)

    Kraaijenbrink, Thirsa; van Driem, George L; Tshering of Gaselô, Karma; de Knijff, Peter

    2007-07-20

    We studied the allele frequency distribution of 21 autosomal STR loci contained in the AmpFlSTR Identifiler (Applied Biosystems), the Powerplex 16 (Promega) and the FFFL (Promega) multiplex PCR kits among 936 individuals from the Royal Kingdom of Bhutan. As such these are the first published autosomal DNA results from this country.

  14. Allelic prevalence of intron 3 insertion/deletion genetic ...

    African Journals Online (AJOL)

    Leila Fallahzadeh-Abarghooei

    2015-03-18

    Mar 18, 2015 ... Tabriz (East Azerbaijan province; belong to Azaris), and Yasuj (Kohgiluyeh va Boyer-Ahmad pro- vince; belong to Lurs), respectively. Genotypic analysis of the Ins/Del XRCC4 polymorphism was detected by the PCR method. Results: The prevalence of the Del allele in Shiraz, Abarku, Tabriz, and Yasuj was ...

  15. Allele frequency analysis of Chinese chestnut ( Castanea mollissima ...

    African Journals Online (AJOL)

    The aim of this study was to establish a method for allele frequency detection in bulk samples. The abundance of polymerase chain reaction (PCR) products in bulk leaf samples was detected using fluorescent labeled Simple sequence repeat (SSR) primers and an Applied biosystems (AB) automatic DNA analyzer.

  16. Association of LEI0258 microsatellite alleles with antibody response ...

    African Journals Online (AJOL)

    SERVER

    2008-03-18

    Mar 18, 2008 ... (MHC) B region on chicken Micro-chromosome 16 has been demonstrated by many workers to be ... promising DNA markers in characterizing MHC B genes. Identifying marker alleles (bands) ..... SAS/STAT Users' Guide,. Release 6.12 Edition, SAS Institute Inc, Cary, North Carolina. USA. Taylor RL (2004).

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

    Indian Academy of Sciences (India)

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

  18. HLA-A alleles differentially associate with severity to Plasmodium ...

    African Journals Online (AJOL)

    Human Leukocyte Antigen (HLA), particularly HLA-B and class II alleles have been differentially associated with disease outcomes in different populations following infection with the malaria Plasmodium falciparum. However, the effect of HLA-A on malaria infection and/or disease is not fully understood. Recently, HLA-A ...

  19. EG-08IDH MUTATIONS IN GLIOMAS ASSOCIATED WITH ENCHONDROMATOSIS

    Science.gov (United States)

    Nicholas, M. Kelly; Joseph, Loren; Venneti, Sriram; Daher, Ahmad; Pytel, Peter

    2014-01-01

    The enchondromatoses, Ollier's disease and Maffucci syndrome, are non-heritable developmental disorders characterized by multiple enchondromas (Olllier's) in association with hemangiomas (Maffucci). Glial neoplasms are reported in both disorders but a pathogenic mechanism underlying this association has not been identified. We report a case of anaplastic astrocytoma in a 23 year old man with Maffucci syndrome whose tumor carried a substitution mutation of arginine for cysteine at position 132 (R132C) of the isocitrate dehydrogenase 1 (IDH1) protein. This mutation, commonly found in Maffucci-associated enchondromas and hemangiomas, was not detected on routine immunohistochemical (IHC) analysis of the astrocytoma using the R132H mutation-specific antibody, commonly applied in clinical laboratories. The R132C mutation was detected by polymerase chain reaction (PCR) and subsequently confirmed using a SNaPshot assay. Because somatic mosaic IDH mutations are associated with enchondromas and hemangiomas in Maffucci syndrome, we looked for the R132C mutation in a hemangioma, peripheral blood mononuclear cells (PBMNC) and histologically normal brain surrounding the tumor from this patient. The mutation was present in the hemangioma, absent in PBMNC, and present in 2% of alleles in ‘normal’ brain. The low level in surrounding brain tissue is consistent with tumor cell infiltration, not mosaicism, as a S173T p53 mutation in the tumor showed similar results. Using IHC, we further demonstrated that the mutant IDH1 protein in this glioma functions as an oncometabolite. Two repressive histone trimethylation marks were strongly positive in the tumor, supporting a role for 2-hydroxyglutarate in the inhibition of histone demethylation. Together, these data demonstrate that an IDH1 mutation common in enchodromatoses underlies the association of glial tumors reported in both Ollier's disease and Maffucci syndrome.

  20. Clonal Ordering of 17p and 5q Allelic Losses in Barrett Dysplasia and Adenocarcinoma

    Science.gov (United States)

    Blount, Patricia L.; Meltzer, Stephen J.; Yin, Jing; Huang, Ying; Krasna, Mark J.; Reid, Brian J.

    1993-04-01

    Both 17p and 5q allelic losses appear to be involved in the pathogenesis or progression of many human solid tumors. In colon carcinogenesis, there is strong evidence that the targets of the 17p and 5q allelic losses are TP53, the gene encoding p53, and APC, respectively. It is widely accepted that 5q allelic losses precede 17p allelic losses in the progression to colonic carcinoma. The data, however, supporting this proposed order are largely based on the prevalence of 17p and 5q allelic losses in adenomas and unrelated adenocarcinomas from different patients. We investigated the order in which 17p and 5q allelic losses developed during neoplastic progression in Barrett esophagus by evaluating multiple aneuploid cell populations from the same patient. Using DNA content flow cytometric cell sorting and polymerase chain reaction, 38 aneuploid cell populations from 14 patients with Barrett esophagus who had high grade dysplasia, cancer or both were evaluated for 17p and 5q allelic losses. 17p allelic losses preceded 5q allelic losses in 7 patients, both 17p and 5q allelic losses were present in all aneuploid populations of 4 patients, and only 17p (without 5q) allelic losses were present in the aneuploid populations of 3 patients. In no patient did we find that a 5q allelic loss preceded a 17p allelic loss. Our data suggest that 17p allelic losses typically occur before 5q allelic losses during neoplastic progression in Barrett esophagus.

  1. Mutational Analysis of the Rhodopsin Gene in Sector Retinitis Pigmentosa.

    Science.gov (United States)

    Napier, Maria L; Durga, Dash; Wolsley, Clive J; Chamney, Sarah; Alexander, Sharon; Brennan, Rosie; Simpson, David A; Silvestri, Giuliana; Willoughby, Colin E

    2015-01-01

    To determine the role of rhodopsin (RHO) gene mutations in patients with sector retinitis pigmentosa (RP) from Northern Ireland. A case series of sector RP in a tertiary ocular genetics clinic. Four patients with sector RP were recruited from the Royal Victoria Hospital (Belfast, Northern Ireland) and Altnagelvin Hospital (Londonderry, Northern Ireland) following informed consent. The diagnosis of sector RP was based on clinical examination, International Society for Clinical Electrophysiology of Vision (ISCEV) standard electrophysiology, and visual field analysis. DNA was extracted from peripheral blood leucocytes and the coding regions and adjacent flanking intronic sequences of the RHO gene were polymerase chain reaction (PCR) amplified and cycle sequenced. Rhodopsin mutational status. A heterozygous missense mutation in RHO (c.173C > T) resulting in a non-conservative substitution of threonine to methionine (p. Thr58Met) was identified in one patient and was absent from 360 control individuals. This non-conservative substitution (p.Thr58Met) replaces a highly evolutionary conserved polar hydrophilic threonine residue with a non-polar hydrophobic methionine residue at position 58 near the cytoplasmic border of helix A of RHO. The study identified a RHO gene mutation (p.Thr58Met) not previously reported in RP in a patient with sector RP. These findings outline the phenotypic variability associated with RHO mutations. It has been proposed that the regional effects of RHO mutations are likely to result from interplay between mutant alleles and other genetic, epigenetic and environmental factors.

  2. [MPLW515L point mutation in patients with myeloproliferative disease].

    Science.gov (United States)

    Xia, Jun; Xu, Wei; Zhang, Su-Jiang; Fan, Lei; Qiao, Chun; Li, Jian-Yong

    2008-12-01

    In order to investigate the frequency of MPLW515L and JAK2V617F point mutations of the patients with myeloproliferative disease (MPD) in Nanjing area, MPLW515L and JAK2V617F point mutations were simultaneously detected by alleles specific polymerase chain reaction (AS-PCR) and sequencing in 190 MPD patients. The results showed that MPLW515L point mutation was detected in 1 out of 102 essential thrombocythemia (ET) patients (1.0%) and was not detected in 32 polycythemia vera (PV) patients, 13 idiopathic myelofibrosis (IMF) patients, 43 chronic myelogenous leukemia (CML) patients. JAK2V617F point mutation was detected in 20 out of 32 PV patients (62.5%), 43 out of 102 ET patients (42.2%), 5 out of 13 IMF patients (38.5%), and was not detected in 43 CML patients. It is concluded that MPLW515L point mutation exists in ET patient, but is not found in PV, IMF and CML. JAK2V617F point mutation exists in PV, ET and IMF, but not in CML.

  3. Novel autosomal dominant TNNT1 mutation causing nemaline myopathy.

    Science.gov (United States)

    Konersman, Chamindra G; Freyermuth, Fernande; Winder, Thomas L; Lawlor, Michael W; Lagier-Tourenne, Clotilde; Patel, Shailendra B

    2017-11-01

    Nemaline myopathy (NEM) is one of the three major forms of congenital myopathy and is characterized by diffuse muscle weakness, hypotonia, respiratory insufficiency, and the presence of nemaline rod structures on muscle biopsy. Mutations in troponin T1 (TNNT1) is 1 of 10 genes known to cause NEM. To date, only homozygous nonsense mutations or compound heterozygous truncating or internal deletion mutations in TNNT1 gene have been identified in NEM. This extended family is of historical importance as some members were reported in the 1960s as initial evidence that NEM is a hereditary disorder. Proband and extended family underwent Sanger sequencing for TNNT1. We performed RT-PCR and immunoblot on muscle to assess TNNT1 RNA expression and protein levels in proband and father. We report a novel heterozygous missense mutation of TNNT1 c.311A>T (p.E104V) that segregated in an autosomal dominant fashion in a large family residing in the United States. Extensive sequencing of the other known genes for NEM failed to identify any other mutant alleles. Muscle biopsies revealed a characteristic pattern of nemaline rods and severe myofiber hypotrophy that was almost entirely restricted to the type 1 fiber population. This novel mutation alters a residue that is highly conserved among vertebrates. This report highlights not only a family with autosomal dominant inheritance of NEM, but that this novel mutation likely acts via a dominant negative mechanism. © 2017 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.

  4. Multiple origins of knockdown resistance mutations in the Afrotropical mosquito vector Anopheles gambiae.

    Directory of Open Access Journals (Sweden)

    João Pinto

    2007-11-01

    Full Text Available How often insecticide resistance mutations arise in natural insect populations is a fundamental question for understanding the evolution of resistance and also for modeling its spread. Moreover, the development of resistance is regarded as a favored model to study the molecular evolution of adaptive traits. In the malaria vector Anopheles gambiae two point mutations (L1014F and L1014S in the voltage-gated sodium channel gene, that confer knockdown resistance (kdr to DDT and pyrethroid insecticides, have been described. In order to determine whether resistance alleles result from single or multiple mutation events, genotyping of the kdr locus and partial sequencing of the upstream intron-1 was performed on a total of 288 A. gambiae S-form collected from 28 localities in 15 countries. Knockdown resistance alleles were found to be widespread in West Africa with co-occurrence of both 1014S and 1014F in West-Central localities. Differences in intron-1 haplotype composition suggest that kdr alleles may have arisen from at least four independent mutation events. Neutrality tests provided evidence for a selective sweep acting on this genomic region, particularly in West Africa. The frequency and distribution of these kdr haplotypes varied geographically, being influenced by an interplay between different mutational occurrences, gene flow and local selection. This has important practical implications for the management and sustainability of malaria vector control programs.

  5. Characterization and Prognosis Significance of JAK2 (V617F), MPL, and CALR Mutations in Philadelphia-Negative Myeloproliferative Neoplasms

    Science.gov (United States)

    Singdong, Roongrudee; Siriboonpiputtana, Teerapong; Chareonsirisuthigul, Takol; Kongruang, Adcharee; Limsuwanachot, Nittaya; Sirirat, Tanasan; Chuncharunee, Suporn; Rerkamnuaychoke, Budsaba

    2016-10-01

    Background: The discovery of somatic acquired mutations of JAK2 (V617F) in Philadelphia-negative myeloproliferative neoplasms (Ph-negative MPNs) including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) has not only improved rational disease classification and prognostication but also brings new understanding insight into the pathogenesis of diseases. Dosage effects of the JAK2 (V617F) allelic burden in Ph-negative MPNs may partially influence clinical presentation, disease progression, and treatment outcome. Material and Methods: Pyrosequencing was performed to detect JAK2 (V617F) and MPL (W515K/L) and capillary electrophoresis to identify CALR exon 9.0 mutations in 100.0 samples of Ph-negative MPNs (38.0 PV, 55 ET, 4 PMF, and 3 MPN-U). Results: The results showed somatic mutations of JAK2 (V617F) in 94.7% of PV, 74.5% of ET, 25.0% of PMF, and all MPN-U. A high proportion of JAK2 (V617F) mutant allele burden (mutational load > 50.0%) was predominantly observed in PV when compared with ET. Although a high level of JAK2 (V617F) allele burden was strongly associated with high WBC counts in both PV and ET, several hematological parameters (hemoglobin, hematocrit, and platelet count) were independent of JAK2 (V617F) mutational load. MPL (W515K/L) mutations could not be detected whereas CALR exon 9.0 mutations were identified in 35.7% of patients with JAK2 negative ET and 33.3% with JAK2 negative PMF. Conclusions: The JAK2 (V617F) allele burden may be involved in progression of MPNs. Furthermore, a high level of JAK2 (V617F) mutant allele appears strongly associated with leukocytosis in both PV and ET. Creative Commons Attribution License

  6. Functional importance of conserved domains in the flowering-time gene CONSTANS demonstrated by analysis of mutant alleles and transgenic plants.

    Science.gov (United States)

    Robson, F; Costa, M M; Hepworth, S R; Vizir, I; Piñeiro, M; Reeves, P H; Putterill, J; Coupland, G

    2001-12-01

    CONSTANS promotes flowering of Arabidopsis in response to long-day conditions. We show that CONSTANS is a member of an Arabidopsis gene family that comprises 16 other members. The CO-Like proteins encoded by these genes contain two segments of homology: a zinc finger containing region near their amino terminus and a CCT (CO, CO-Like, TOC1) domain near their carboxy terminus. Analysis of seven classical co mutant alleles demonstrated that the mutations all occur within either the zinc finger region or the CCT domain, confirming that the two regions of homology are important for CO function. The zinc fingers are most similar to those of B-boxes, which act as protein-protein interaction domains in several transcription factors described in animals. Segments of CO protein containing the CCT domain localize GFP to the nucleus, but one mutation that affects the CCT domain delays flowering without affecting the nuclear localization function, suggesting that this domain has additional functions. All eight co alleles, including one recovered by pollen irradiation in which DNA encoding both B-boxes is deleted, are shown to be semidominant. This dominance appears to be largely due to a reduction in CO dosage in the heterozygous plants. However, some alleles may also actively delay flowering, because overexpression from the CaMV 35S promoter of the co-3 allele, that has a mutation in the second B-box, delayed flowering of wild-type plants. The significance of these observations for the role of CO in the control of flowering time is discussed.

  7. QuASAR: quantitative allele-specific analysis of reads.

    Science.gov (United States)

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

    2015-04-15

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

  8. Segregation of male-sterility alleles across a species boundary.

    Science.gov (United States)

    Weller, S G; Sakai, A K; Culley, T M; Duong, L; Danielson, R E

    2014-02-01

    Hybrid zones may serve as bridges permitting gene flow between species, including alleles influencing the evolution of breeding systems. Using greenhouse crosses, we assessed the likelihood that a hybrid zone could serve as a conduit for transfer of nuclear male-sterility alleles between a gynodioecious species and a hermaphroditic species with very rare females in some populations. Segregation patterns in progeny of crosses between rare females of hermaphroditic Schiedea menziesii and hermaphroditic plants of gynodioecious Schiedea salicaria heterozygous at the male-sterility locus, and between female S. salicaria and hermaphroditic plants from the hybrid zone, were used to determine whether male-sterility was controlled at the same locus in the parental species and the hybrid zone. Segregations of females and hermaphrodites in approximately equal ratios from many of the crosses indicate that the same nuclear male-sterility allele occurs in the parent species and the hybrid zone. These rare male-sterility alleles in S. menziesii may result from gene flow from S. salicaria through the hybrid zone, presumably facilitated by wind pollination in S. salicaria. Alternatively, rare male-sterility alleles might result from a reversal from gynodioecy to hermaphroditism in S. menziesii, or possibly de novo evolution of male sterility. Phylogenetic analysis indicates that some species of Schiedea have probably evolved separate sexes independently, but not in the lineage containing S. salicaria and S. menziesii. High levels of selfing and expression of strong inbreeding depression in S. menziesii, which together should favour females in populations, argue against a reversal from gynodioecy to hermaphroditism in S. menziesii. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  9. Prevalence of GJB2 Mutations in Affected Individuals from United Arab Emirates with Autosomal Recessive Nonsyndromic Hearing Loss.

    Science.gov (United States)

    Tlili, Abdelaziz; Al Mutery, Abdullah; Kamal Eddine Ahmad Mohamed, Walaa; Mahfood, Mona; Hadj Kacem, Hassen

    2017-11-01

    Mutations in the gap junction protein beta 2 (GJB2) gene are responsible for more cases of nonsyndromic recessive hearing loss than any other gene. The purpose of our study was to evaluate the prevalence of GJB2 mutations among affected individuals from United Arab Emirates (UAE). There were 50 individuals diagnosed with hereditary hearing loss and 120 healthy individuals enrolled in the study. The Sanger sequencing method was used to screen the GJB2 coding region in all affected individuals. The c.-1G>A variant was determined by the polymerase chain reaction-restriction fragment length polymorphism method in normal individuals. Nine cases with bi-allelic mutations and three cases with mono-allelic mutations were detected in 12 out of 50 patients (24%). The homozygous mutation c.35delG was identified as the cause of hearing loss in six participants (12%). The mutation c.506G>A was identified in three affected individuals (6%). The allelic frequency (14%) and low percentage of individuals that were homozygous (2%) for the c.35delG mutation suggest that there are other genes responsible for nonsyndromic deafness in the UAE population. The results reported here are a preliminary step in collecting epidemiological data regarding autosomal recessive nonsyndromic hearing loss related to GJB2 gene mutations among the UAE population. The c.35delG mutation of the GJB2 gene is the most frequently seen causative mutation in the UAE and is followed by the p.Cys169Tyr mutation.

  10. Acquired copy-neutral loss of heterozygosity of chromosome 1p as a molecular event associated with marrow fibrosis in MPL-mutated myeloproliferative neoplasms.

    Science.gov (United States)

    Rumi, Elisa; Pietra, Daniela; Guglielmelli, Paola; Bordoni, Roberta; Casetti, Ilaria; Milanesi, Chiara; Sant'Antonio, Emanuela; Ferretti, Virginia; Pancrazzi, Alessandro; Rotunno, Giada; Severgnini, Marco; Pietrelli, Alessandro; Astori, Cesare; Fugazza, Elena; Pascutto, Cristiana; Boveri, Emanuela; Passamonti, Francesco; De Bellis, Gianluca; Vannucchi, Alessandro; Cazzola, Mario

    2013-05-23

    We studied mutations of MPL exon 10 in patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF), first investigating a cohort of 892 consecutive patients. MPL mutation scanning was performed on granulocyte genomic DNA by using a high-resolution melt assay, and the mutant allele burden was evaluated by using deep sequencing. Somatic mutations of MPL, all but one involving codon W515, were detected in 26/661 (4%) patients with ET, 10/187 (5%) with PMF, and 7/44 (16%) patients with post-ET myelofibrosis. Comparison of JAK2 (V617F)-mutated and MPL-mutated patients showed only minor phenotypic differences. In an extended group of 62 MPL-mutated patients, the granulocyte mutant allele burden ranged from 1% to 95% and was significantly higher in patients with PMF or post-ET myelofibrosis compared with those with ET. Patients with higher mutation burdens had evidence of acquired copy-neutral loss of heterozygosity (CN-LOH) of chromosome 1p in granulocytes, consistent with a transition from heterozygosity to homozygosity for the MPL mutation in clonal cells. A significant association was found between MPL-mutant allele burden greater than 50% and marrow fibrosis. These observations suggest that acquired CN-LOH of chromosome 1p involving the MPL location may represent a molecular mechanism of fibrotic transformation in MPL-mutated myeloproliferative neoplasms.

  11. Identification of four new mutations in the short-chain acyl-CoA dehydrogenase (SCAD) gene in two patients

    DEFF Research Database (Denmark)

    Gregersen, N; Winter, V S; Corydon, M J

    1998-01-01

    We have shown previously that a variant allele of the short-chain acyl-CoA dehydrogenase ( SCAD ) gene, 625G-->A, is present in homozygous form in 7% of control individuals and in 60% of 135 patients with elevated urinary excretion of ethylmalonic acid (EMA). We have now characterized three disease......-causing mutations (confirmed by lack of enzyme activity after expression in COS-7 cells) and a new susceptibility variant in the SCAD gene of two patients with SCAD deficiency, and investigated their frequency in patients with elevated EMA excretion. The first SCAD-deficient patient was a compound heterozygote...... for two mutations, 274G-->T and 529T-->C. These mutations were not present in 98 normal control alleles, but the 529T-->C mutation was found in one allele among 133 patients with elevated EMA excretion. The second patient carried a 1147C-->T mutation and the 625G-->A polymorphism in one allele...

  12. A novel common large genomic deletion and two new missense mutations identified in the Romanian phenylketonuria population.

    Science.gov (United States)

    Gemperle-Britschgi, Corinne; Iorgulescu, Daniela; Mager, Monica Alina; Anton-Paduraru, Dana; Vulturar, Romana; Thöny, Beat

    2016-01-15

    The mutation spectrum for the phenylalanine hydroxylase (PAH) gene was investigated in a cohort of 84 hyperphenylalaninemia (HPA) patients from Romania identified through newborn screening or neurometabolic investigations. Differential diagnosis identified 81 patients with classic PAH deficiency while 3 had tetrahydropterin-cofactor deficiency and/or remained uncertain due to insufficient specimen. PAH-genetic analysis included a combination of Sanger sequencing of exons and exon–intron boundaries, MLPA and NGS with genomic DNA, and cDNA analysis from immortalized lymphoblasts. A diagnostic efficiency of 99.4% was achieved, as for one allele (out of a total of 162 alleles) no mutation could be identified. The most prevalent mutation was p.Arg408Trp which was found in ~ 38% of all PKU alleles. Three novel mutations were identified, including the two missense mutations p.Gln226Lys and p.Tyr268Cys that were both disease causing by prediction algorithms, and the large genomic deletion EX6del7831 (c.509 + 4140_706 + 510del7831) that resulted in skipping of exon 6 based on PAH-cDNA analysis in immortalized lymphocytes. The genomic deletion was present in a heterozygous state in 12 patients, i.e. in ~ 8% of all the analyzed PKU alleles, and might have originated from a Romanian founder.

  13. Biallelic germline and somatic mutations in malignant mesothelioma: multiple mutations in transcription regulators including mSWI/SNF genes.

    Science.gov (United States)

    Yoshikawa, Yoshie; Sato, Ayuko; Tsujimura, Tohru; Otsuki, Taiichiro; Fukuoka, Kazuya; Hasegawa