55 research outputs found

    FRA2A is a CGG repeat expansion associated with silencing of AFF3

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    Folate-sensitive fragile sites (FSFS) are a rare cytogenetically visible subset of dynamic mutations. Of the eight molecularly characterized FSFS, four are associated with intellectual disability (ID). Cytogenetic expression results from CGG tri-nucleotide-repeat expansion mutation associated with local CpG hypermethylation and transcriptional silencing. The best studied is the FRAXA site in the FMR1 gene, where large expansions cause fragile X syndrome, the most common inherited ID syndrome. Here we studied three families with FRA2A expression at 2q11 associated with a wide spectrum of neurodevelopmental phenotypes. We identified a polymorphic CGG repeat in a conserved, brain-active alternative promoter of the AFF3 gene, an autosomal homolog of the X-linked AFF2/FMR2 gene: Expansion of the AFF2 CGG repeat causes FRAXE ID. We found that FRA2A-expressing individuals have mosaic expansions of the AFF3 CGG repeat in the range of several hundred repeat units. Moreover, bisulfite sequencing and pyrosequencing both suggest AFF3 promoter hypermethylation. cSNP-analysis demonstrates monoallelic expression of the AFF3 gene in FRA2A carriers thus predicting that FRA2A expression results in functional haploinsufficiency for AFF3 at least in a subset of tissues. By whole-mount in situ hybridization the mouse AFF3 ortholog shows strong regional expression in the developing brain, somites and limb buds in 9.5-12.5dpc mouse embryos. Our data suggest that there may be an association between FRA2A and a delay in the acquisition of motor and language skills in the families studied here. However, additional cases are required to firmly establish a causal relationship

    Identification of rare de novo epigenetic variations in congenital disorders

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    Certain human traits such as neurodevelopmental disorders (NDs) and congenital anomalies (CAs) are believed to be primarily genetic in origin. However, even after whole-genome sequencing (WGS), a substantial fraction of such disorders remain unexplained. We hypothesize that some cases of ND-CA are caused by aberrant DNA methylation leading to dysregulated genome function. Comparing DNA methylation profiles from 489 individuals with ND-CAs against 1534 controls, we identify epivariations as a frequent occurrence in the human genome. De novo epivariations are significantly enriched in cases, while RNAseq analysis shows that epivariations often have an impact on gene expression comparable to loss-of-function mutations. Additionally, we detect and replicate an enrichment of rare sequence mutations overlapping CTCF binding sites close to epivariations, providing a rationale for interpreting non-coding variation. We propose that epivariations contribute to the pathogenesis of some patients with unexplained ND-CAs, and as such likely have diagnostic relevance.The authors are grateful to the patients and families who participated in this study and to the collaborators who supported patient recruitment. This work was supported by NIH grant HG006696 and research grant 6-FY13-92 from the March of Dimes to A.J.S., grant HL098123 to B.D.G. and A.J.S., Gulbenkian Programme for Advanced Medical Education and the Portuguese Foundation for Science and Technology (SFRH/BDINT/51549/ 2011, PIC/IC/83026/2007, PIC/IC/83013/2007, SFRH/BD/90167/2012, Portugal) to P.M., F.L., and M.B., by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) (NORTE-01-0145-FEDER-000013) to P.M., a Beatriu de Pinos Postdoctoral Fellowship to R.S.J. (2011BP-A00515), and a Seaver Foundation fellowship to S.D.R. The views expressed are those of the authors and do not necessarily reflect those of the National Heart, Lung, and Blood Institute or the National Institutes of Health. Research reported in this paper was supported by the Office of Research Infrastructure of the National Institutes of Health under award number S10OD018522. This work was supported in part through the computational resources and staff expertise provided by Scientific Computing at the Icahn School of Medicine at Mount Sinai.The authors are grateful to the patients and families who participated in this study and to the collaborators who supported patient recruitment. This work was supported by NIH grant HG006696 and research grant 6-FY13-92 from the March of Dimes to A.J.S., grant HL098123 to B.D.G. and A.J.S., Gulbenkian Programme for Advanced Medical Education and the Portuguese Foundation for Science and Technology (SFRH/BDINT/51549/ 2011, PIC/IC/83026/2007, PIC/IC/83013/2007, SFRH/BD/90167/2012, Portugal) to P.M., F.L., and M.B., by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) (NORTE-01-0145-FEDER-000013) to P.M., a Beatriu de Pinos Postdoctoral Fellowship to R.S.J. (2011BP-A00515), and a Seaver Foundation fellowship to S.D.R. The views expressed are those of the authors and do not necessarily reflect those of the National Heart, Lung, and Blood Institute or the National Institutes of Health. Research reported in this paper was supported by the Office of Research Infrastructure of the National Institutes of Health under award number S10OD018522. This work was supported in part through the computational resources and staff expertise provided by Scientific Computing at the Icahn School of Medicine at Mount Sinai

    FCGR polymorphisms in the treatment of rheumatoid arthritis with Fc-containing TNF inhibitors

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    [EN] Objectives: Reproducible association of a functional polymorphism in FCGR2A with response to a TNF inhibitor (TNFi) in patients with rheumatoid arthritis (RA) led us to explore other Fc?R functional polymorphisms. Methods: Functional polymorphisms FCGR3A F158V, FCGR2B I223T and promoter VNTR in FCGRT were analyzed in up to 429 patients with RA. Response to TNFi was recorded during standard care at 3, 6 and 12 months of follow-up. Fixed effects meta-analysis of studies addressing FCGR3A F158V polymorphism, which is the most studied of these polymorphisms, was conducted with inverse variance weighting. Results: None of the functional polymorphisms were associated with change in DAS28. Meta-analysis of the seven studies (899 patients) with available data addressing association of FCGR3A F158V with response to TNFi in RA showed no association (OR: 1.11, 95% CI: 0.8-1.5; p = 0.5). Conclusion: None of the three functional polymorphisms in Fc?R genes showed association with response to TNFi in patients with RA. These negative results were obtained in spite of the larger size of this study relative to previous studies addressing the same polymorphisms. In addition, meta-analysis of FCGR3A F158V was also negative against the results provided by previous studies

    The role of DNA damage response pathways in chromosome fragility in Fragile X syndrome

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    FRAXA is one of a number of fragile sites in human chromosomes that are induced by agents like fluorodeoxyuridine (FdU) that affect intracellular thymidylate levels. FRAXA coincides with a >200 CGG•CCG repeat tract in the 5′ UTR of the FMR1 gene, and alleles prone to fragility are associated with Fragile X (FX) syndrome, one of the leading genetic causes of intellectual disability. Using siRNA depletion, we show that ATR is involved in protecting the genome against FdU-induced chromosome fragility. We also show that FdU increases the number of γ-H2AX foci seen in both normal and patient cells and increases the frequency with which the FMR1 gene colocalizes with these foci in patient cells. In the presence of FdU and KU55933, an ATM inhibitor, the incidence of chromosome fragility is reduced, suggesting that ATM contributes to FdU-induced chromosome fragility. Since both ATR and ATM are involved in preventing aphidicolin-sensitive fragile sites, our data suggest that the lesions responsible for aphidicolin-induced and FdU-induced fragile sites differ. FRAXA also displays a second form of chromosome fragility in absence of FdU, which our data suggest is normally prevented by an ATM-dependent process

    Lack of validation of genetic variants associated with anti-tumor necrosis factor therapy response in rheumatoid arthritis: a genome-wide association study replication and meta-analysis

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    Introduction: In this study, our aim was to elucidate the role of four polymorphisms identified in a prior large genome-wide association study (GWAS) in which the investigators analyzed the responses of patients with rheumatoid arthritis (RA) to treatment with tumor necrosis factor inhibitors (TNFi). The authors of that study reported that the four genetic variants were significantly associated. However, none of the associations reached GWAS significance, and two subsequent studies failed to replicate these associations. Methods: The four polymorphisms (rs12081765, rs1532269, rs17301249 and rs7305646) were genotyped in a total of 634 TNFi-treated RA patients of Spanish Caucasian origin. Four outcomes were evaluated: changes in the Disease Activity Score in 28 joints (DAS28) after 6 and 12 months of treatment and classification according to the European League Against Rheumatism (EULAR) response criteria at the same time points. Association with DAS28 changes was assessed by linear regression using an additive genetic model. Contingency tables of genotype and allele frequencies between EULAR responder and nonresponder patients were compared. In addition, we combined our data with those of previously reported studies in a meta-analysis including 2,998 RA patients. Results: None of the four genetic variants showed an association with response to TNFi in any of the four outcomes analyzed in our Spanish patients. In addition, only rs1532269 yielded a suggestive association (P = 0.0033) with the response to TNFi when available data from previous studies were combined in the meta-analysis. Conclusion: Our data suggest that the rs12081765, rs1532269, rs17301249 and rs7305646 genetic variants do not have a role as genetic predictors of TNFi treatment outcomes

    Wide-Geographic and Long-Term Analysis of the Role of Pathogens in the Decline of Pinna nobilis to Critically Endangered Species

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    A mass mortality event (MME) affecting the fan mussel Pinna nobilis was first detected in Spain in autumn 2016 and spread north- and eastward through the Mediterranean Sea. Various pathogens have been blamed for contributing to the MME, with emphasis in Haplosporidium pinnae, Mycobacterium sp. and Vibrio spp. In this study, samples from 762 fan mussels (necropsies from 263 individuals, mantle biopsies from 499) of various health conditions, with wide geographic and age range, taken before and during the MME spread from various environments along Mediterranean Sea, were used to assess the role of pathogens in the MME. The number of samples processed by both histological and molecular methods was 83. The most important factor playing a main role on the onset of the mass mortality of P. nobilis throughout the Mediterranean Sea was the infection by H. pinnae. It was the only non-detected pathogen before the MME while, during MME spreading, its prevalence was higher in sick and dead individuals than in asymptomatic ones, in MME-affected areas than in non-affected sites, and it was not associated with host size, infecting both juveniles and adults. Conversely, infection with mycobacteria was independent from the period (before or during MME), from the affection of the area by MME and from the host health condition, and it was associated with host size. Gram (-) bacteria neither appeared associated with MME.En prens

    Rheumatoid arthritis response to treatment across IgG1 allotype - anti-TNF incompatibility: a case-only study.

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    INTRODUCTION: We have hypothesized that incompatibility between the G1m genotype of the patient and the G1m1 and G1m17 allotypes carried by infliximab (INX) and adalimumab (ADM) could decrease the efficacy of these anti-tumor necrosis factor (anti-TNF) antibodies in the treatment of rheumatoid arthritis (RA). METHODS: The G1m genotypes were analyzed in three collections of patients with RA totaling 1037 subjects. The first, used for discovery, comprised 215 Spanish patients. The second and third were successively used for replication. They included 429 British and Greek patients and 393 Spanish and British patients, respectively. Two outcomes were considered: change in the Disease Activity Score in 28 joint (ΔDAS28) and the European League Against Rheumatism (EULAR) response criteria. RESULTS: An association between less response to INX and incompatibility of the G1m1,17 allotype was found in the discovery collection at 6 months of treatment (P = 0.03). This association was confirmed in the replications (P = 0.02 and 0.08, respectively) leading to a global association (P = 0.001) that involved a mean difference in ΔDAS28 of 0.4 units between compatible and incompatible patients (2.3 ± 1.5 in compatible patients vs. 1.9 ± 1.5 in incompatible patients) and an increase in responders and decrease in non-responders according to the EULAR criteria (P = 0.03). A similar association was suggested for patients treated with ADM in the discovery collection, but it was not supported by replication. CONCLUSIONS: Our results suggest that G1m1,17 allotypes are associated with response to INX and could aid improved therapeutic targeting in RA

    Genome-Wide association study (GWAS) for growth rate and age at sexual maturation in atlantic salmon (Salmo salar)

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    Early sexual maturation is considered a serious drawback for Atlantic salmon aquaculture as it retards growth, increases production times and affects flesh quality. Although both growth and sexual maturation are thought to be complex processes controlled by several genetic and environmental factors, selection for these traits has been continuously accomplished since the beginning of Atlantic salmon selective breeding programs. In this genome-wide association study (GWAS) we used a 6.5K single-nucleotide polymorphism (SNP) array to genotype ∼480 individuals from the Cermaq Canada broodstock program and search for SNPs associated with growth and age at sexual maturation. Using a mixed model approach we identified markers showing a significant association with growth, grilsing (early sexual maturation) and late sexual maturation. The most significant associations were found for grilsing, with markers located in Ssa10, Ssa02, Ssa13, Ssa25 and Ssa12, and for late maturation with markers located in Ssa28, Ssa01 and Ssa21. A lower level of association was detected with growth on Ssa13. Candidate genes, which were linked to these genetic markers, were identified and some of them show a direct relationship with developmental processes, especially for those in association with sexual maturation. However, the relatively low power to detect genetic markers associated with growth (days to 5 kg) in this GWAS indicates the need to use a higher density SNP array in order to overcome the low levels of linkage disequilibrium observed in Atlantic salmon before the information can be incorporated into a selective breeding program

    Teacher participation in decision making and its impact on school and teachers

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    Purpose: The purpose of this paper is to examine teacher involvement in different domains of decision making in Greek primary schools and explore associations with school and teacher variables. Design/methodology/approach: A survey employing self-administered questionnaires, with a Likert-type scale assessing teachers' actual and desired participation in three domains of decision making, was used. Scales measuring perceived school climate, self-efficacy and job satisfaction were also included. Data were collected from 143 teachers working in primary schools located in different areas in Greece. Findings: The multidimensional approach to measuring teacher participation in decision making revealed quite high actual participation in decisions concerning students' and teachers' issues, but low levels of participation in managerial decisions. The discrepancy between the actual and desired levels of participation showed significant deprivation across all decision-making domains. Greater participation in decisions concerning teacher issues and lower levels of deprivation of participating in managerial issues were associated with teachers' perceptions of better leadership and higher collegiality in schools. The strongest predictor of both teachers' sense of efficacy and job satisfaction was their participation in decisions concerning teacher issues. Practical implications: Educational leaders should promote forms of participation in decision making that increase teachers' actual involvement in decisions concerning their duties and opportunities for development and also provide for more sharing on issues concerning the school management, particularly for women. Originality/value: The study underlines the value of dimensionality in investigating decision making in schools. © Emerald Group Publishing Limited
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