223 research outputs found
Genetic Susceptibility to Differentiated Thyroid Cancer
Differentiated thyroid carcinoma (DTC) represents more than 90% of all thyroid cancer histological types. Its incidence has increased at a faster rate than most other malignancies during the last three decades and varies considerably around the world. The familial form of the disease has also become more common than previously reported, accounting for 5−15% of DTC cases. The main established risk factor of thyroid cancer is exposure to ionizing radiation, particularly if occurred during childhood. Thyroid cancer (including DTC) is also characterized by having one of the highest familial risks of any cancer supporting heritable predisposition. In spite of such a high familial risk, linkage analysis in non-syndromic DTC families (i.e. families where DTC is the primary cancer) performed two decades ago mapped several susceptibility loci but did not lead to the identification of high-penetrance causal germline variants. More recently, genome-wide association studies based on population case–control studies identified a limited number of DTC-associated loci and suggested that multiple low penetrance genes are involved in predisposition to DTC. This chapter reviews known genetic factors predisposing to DTC as well as approaches used to map them in various populations, and opens up on alternative strategies that could help to understand DTC tumorigenesis
Characteristics and correlates of seclusion and mechanical restraint measures in a Parisian psychiatric hospital group
IntroductionSeclusion or restraint (S/R) are last-resort measures used in psychiatry to ensure the safety of the patient and the staff. However, they have harmful physical and psychological effects on patients, and efforts to limit their use are needed. We describe the characteristics and correlates of S/R events in four Parisian psychiatric centers.MethodsWithin a 3-month period, November 5, 2018 to February 3, 2019, we recorded data for patients experiencing an S/R measure as well as characteristics of the measures. We studied the mean duration of a S/R event, the time between hospital admission and the occurrence of the event, as well as correlates of these durations. We also examined factors associated with use of a restraint versus a seclusion measure.ResultsFor the 233 patients included, we recorded 217 seclusion measures and 64 mechanical restraints. Seclusion measures mostly occurred after the patient’s transfer from the emergency department. The duration of a seclusion measure was about 10 days. Patients considered resistant to psychotropic treatments more frequently had a longer seclusion duration than others. The mean duration of a mechanical restraint measure was 4 days. Male sex and younger age were associated with experiencing mechanical restraint.DiscussionS/R measures mostly occur among patients perceived as resistant to psychotropic drugs who are arriving from the emergency department. Developing specific emergency department protocols might be useful in limiting the use of coercive measures
Determining the effectiveness of High Resolution Melting analysis for SNP genotyping and mutation scanning at the TP53 locus
<p>Abstract</p> <p>Background</p> <p>Together single nucleotide substitutions and small insertion/deletion variants are the most common form of sequence variation in the human gene pool.</p> <p>High-resolution SNP profile and/or haplotype analyses enable the identification of modest-risk susceptibility genes to common diseases, genes that may modulate responses to pharmaceutical agents, and SNPs that can affect either their expression or function. In addition, sensitive techniques for germline or somatic mutation detection are important tools for characterizing sequence variations in genes responsible for tumor predisposition. Cost-effective methods are highly desirable. Many of the recently developed high-throughput technologies are geared toward industrial scale genetic studies and arguably do not provide useful solutions for small laboratory investigator-initiated projects. Recently, the use of new fluorescent dyes allowed the high-resolution analysis of DNA melting curves (HRM).</p> <p>Results</p> <p>Here, we compared the capacity of HRM, applicable to both genotyping and mutation scanning, to detect genetic variations in the tumor suppressor gene <it>TP53 </it>with that of mutation screening by full resequencing. We also assessed the performance of a variety of available HRM-based genotyping assays by genotyping 30 <it>TP53 </it>SNPs. We describe a series of solutions to handle the difficulties that may arise in large-scale application of HRM to mutation screening and genotyping at the <it>TP53 </it>locus. In particular, we developed specific HRM assays that render possible genotyping of 2 or more, sometimes closely spaced, polymorphisms within the same amplicon. We also show that simultaneous genotyping of 2 SNPs from 2 different amplicons using a multiplex PCR reaction is feasible; the data can be analyzed in a single HRM run, potentially improving the efficiency of HRM genotyping workflows.</p> <p>Conclusion</p> <p>The HRM technique showed high sensitivity and specificity (1.0, and 0.8, respectively, for amplicons of <400 bp) for mutation screening and provided useful genotyping assays as assessed by comparing the results with those obtained with Sanger sequencing. Thus, HRM is particularly suitable for either performing mutation scanning of a large number of samples, even in the situation where the amplicon(s) of interest harbor a common variant that may disturb the analysis, or in a context where gathering common SNP genotypes is of interest.</p
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Common variation in EMSY and risk of breast and ovarian cancer: a case-control study using HapMap tagging SNPs.
BACKGROUND: EMSY could be involved in low-level susceptibility to breast and ovarian cancer. Gene amplification is seen in a proportion of breast and ovarian tumours and correlates with poor prognosis in breast cancer patients. Furthermore, the EMSY protein silences a transcription activation domain in BRCA2 exon 3. METHODS: We used a genetic association study design to determine if common genetic variation (frequency > or = 5%) in EMSY was associated with breast or ovarian cancer risk in the British population. Haplotype tagging single-nucleotide polymorphisms (htSNPs) were selected from the HapMap database and genotyped using Taqman in two large study sets of white British women (n [breast set] = 2343 cases and 2284 controls, n [ovarian set] = 864 cases and 864 controls). HapMap data might be insufficient to tag genetic variation in EMSY comprehensively. We therefore screened the gene promoter and coding sequences with denaturing high performance liquid chromatography in order to identify additional SNPs that are most likely to be functional. RESULTS: HapMap data on 22 SNPs show that 4 htSNPs tag 4 common haplotypes: rs2282611 (5'up t > g), rs4245443 (IVS7 g > a), rs2513511 (IVS16 a > g), rs2155220 (3'down c > t). We observed no association between any of the genotypes or associated haplotypes and breast or ovarian cancer risk. Seventeen out of the 18 remaining HapMap polymorphisms (94%) were well tagged by the 4 selected htSNPs (r2s > 0.8). Genotype frequencies for two further SNPs identified by screening and located near exon-intron boundaries, rs2508740 (IVS9 a > g) and rs11600501 (IVS10 c > t), were also similar in cases and controls. In order to simulate unidentified SNPs, we performed the leave-one-out cross-validation procedure on the HapMap data; over 95% of the common genetic variation was well represented by tagging polymorphisms. We are therefore likely to have tagged any common, functional variants present in our population. CONCLUSION: We found no association between common genetic variation in EMSY and risk of breast or ovarian cancer in two large study sets of white British women
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Common ERBB2 polymorphisms and risk of breast cancer in a white British population: a case-control study.
INTRODUCTION: About two-thirds of the excess familial risk associated with breast cancer is still unaccounted for and may be explained by multiple weakly predisposing alleles. A gene thought to be involved in low-level predisposition to the disease is ERBB2 (HER2). This gene is involved in cell division, differentiation, and apoptosis and is frequently amplified in breast tumours. Its amplification correlates with poor prognosis. Moreover, the coding polymorphism I655V has previously been associated with an increased risk of breast cancer. METHODS: We aimed to determine if common polymorphisms (frequency >or= 5%) in ERBB2 were associated with breast cancer risk in a white British population. Five single-nucleotide polymorphisms (SNPs) were selected for study: SNP 1 near the promoter, SNP 2 in intron 1, SNP 3 in intron 4, SNP 4 in exon 17 (I655V), and SNP 5 in exon 27 (A1170P). We tested their association with breast cancer in a large case-control study (n = 2192 cases and 2257 controls). RESULTS: There were no differences in genotype frequencies between cases and controls for any of the SNPs examined. To investigate the possibility that a common polymorphism not included in our study might be involved in breast cancer predisposition, we also constructed multilocus haplotypes. Our set of SNPs generated all existing (n = 6) common haplotypes and no differences were seen in haplotype frequencies between cases and controls (P = 0.44). CONCLUSIONS: In our population, common ERBB2 polymorphisms are not involved in predisposition to breast cancer
Genetics and molecular epidemiology of multiple myeloma : the rationale for the IMMEnSE consortium (review)
There is strong evidence suggesting the presence of a genetic component in the aetiology of multiple myeloma (MM). However no genetic risk factors have been unequivocally established so far. To further our understanding of the genetic determinants of MM risk, a promising strategy is to collect a large set of patients in a consortium, as successfully done for other cancers. In this article, we review the main findings in the genetic susceptibility and pharmacogenetics of MM and present the strategy of the IMMEnSE (International Multiple Myeloma rESEarch) consortium in contributing to determine the role of genetic variation in pharmacogenetics and in MM risk.We acknowledge support by the recruiting hospitals and physicians of the study regions as well as their collaborating nurses and technicians. Collection of blood samples from Spain, patients from Granada area and DNA extraction was partially supported by grants P08-CVI-4116 from Consejeria de Salud de la Junta de Andalucia (Sevilla, Spain) and PI081051 from Fondo de Investigaciones Sanitarias (Madrid, Spain). Collection of blood samples from Polish patients and controls from Lodz area and DNA extraction was supported by a grant from Polish Ministry of Science and Higher Education (No. N N402178334)
A common variant within the HNF1B gene is associated with overall survival of multiple myeloma patients: results from the IMMEnSE consortium and meta-analysis
Diabetogenic single nucleotide polymorphisms (SNPs) have recently been associated with multiple myeloma (MM) risk but their impact on overall survival (OS) of MM patients has not been analysed yet. In order to investigate the impact of 58 GWAS-identified variants for type 2 diabetes (T2D) on OS of patients with MM, we analysed genotyping data of 936 MM patients collected by the International Multiple Myeloma rESEarch (IMMENSE) consortium and an independent set of 700 MM patients recruited by the University Clinic of Heidelberg. A meta-analysis of the cox regression results of the two sets showed that rs7501939 located in the HNF1B gene negatively impacted OS (HRRec = 1.44, 95% CI = 1.18-1.76, P = 0.0001). The meta-analysis also showed a noteworthy gender-specific association of the SLC30A8(rs13266634) SNP with OS. The presence of each additional copy of the minor allele at rs13266634 was associated with poor OS in men whereas no association was seen in women (HRMen-Add = 1.32, 95% CI 1.13-1.54, P = 0.0003). In conclusion, these data suggest that the HNF1B(rs7501939) SNP confers poor OS in patients with MM and that a SNP in SLC30A8 affect OS in men.This work was supported by grants from the FIBAO foundation (Granada, Spain), from the CRIS foundation against cancer, from the Cancer Network of Excellence (RD12/10 Red de Cáncer), from the Instituto de Salud Carlos III (Madrid, Spain; PI12/02688) and from the Dietmar Hopp Foundation and the German Ministry of Education and Science (BMBF: CLIOMMICS [01ZX1309]).FIBAO
foundation (Granada, Spain), from
the
CRIS foundation
against cancer, from the Cancer Network of Excellence
(RD12/10 Red de Cáncer), from the Instituto de Salud
Carlos III (Madrid, Spain; PI12/02688) and from the
Dietmar Hopp Foundation and the German Ministry
of Education and Science (BMBF: CLIOMMICS
[01ZX1309]info:eu-repo/semantics/publishedVersio
Type 2 diabetes-related variants influence the risk of developing multiple myeloma: results from the IMMEnSE consortium
Type 2 diabetes (T2D) has been suggested to be a risk factor for multiple myeloma (MM), but the relationship between the two traits is still not well understood. The aims of this study were to evaluate whether 58 genome-wide-association-studies (GWAS)-identified common variants for T2D influence the risk of developing MM and to determine whether predictive models built with these variants might help to predict the disease risk. We conducted a case–control study including 1420 MM patients and 1858 controls ascertained through the International Multiple Myeloma (IMMEnSE) consortium. Subjects carrying the KCNQ1rs2237892T allele or the CDKN2A-2Brs2383208G/G, IGF1rs35767T/T and MADDrs7944584T/T genotypes had a significantly increased risk of MM (odds ratio (OR)=1.32–2.13) whereas those carrying the KCNJ11rs5215C, KCNJ11rs5219T and THADArs7578597C alleles or the FTOrs8050136A/A and LTArs1041981C/C genotypes showed a significantly decreased risk of developing the disease (OR=0.76–0.85). Interestingly, a prediction model including those T2D-related variants associated with the risk of MM showed a significantly improved discriminatory ability to predict the disease when compared to a model without genetic information (area under the curve (AUC)=0.645 vs AUC=0.629; P=4.05×10-06). A gender-stratified analysis also revealed a significant gender effect modification for ADAM30rs2641348 and NOTCH2rs10923931 variants (Pinteraction=0.001 and 0.0004, respectively). Men carrying the ADAM30rs2641348C and NOTCH2rs10923931T alleles had a significantly decreased risk of MM whereas an opposite but not significant effect was observed in women (ORM=0.71 and ORM=0.66 vs ORW=1.22 and ORW=1.15, respectively). These results suggest that TD2-related variants may influence the risk of developing MM and their genotyping might help to improve MM risk prediction models.This work was supported by grants from the FIBAO foundation (Granada, Spain) and the CRIS foundation against cancer, from the Cancer Network of Excellence (RD12/10 Red de Cancer) and from the Instituto de Salud Carlos III (Madrid, Spain; PI12/02688)
ADAM33, a New Candidate for Psoriasis Susceptibility
Psoriasis is a chronic skin disorder with multifactorial etiology. In a recent study, we reported results of a genome-wide scan on 46 French extended families presenting with plaque psoriasis. In addition to unambiguous linkage to the major susceptibility locus PSORS1 on Chromosome 6p21, we provided evidence for a susceptibility locus on Chromosome 20p13. To follow up this novel psoriasis susceptibility locus we used a family-based association test (FBAT) for an association scan over the 17 Mb candidate region. A total of 85 uncorrelated SNP markers located in 65 genes of the region were initially investigated in the same set of large families used for the genome wide search, which consisted of 295 nuclear families. When positive association was obtained for a SNP, candidate genes nearby were explored more in detail using a denser set of SNPs. Thus, the gene ADAM33 was found to be significantly associated with psoriasis in this family set (The best association was on a 3-SNP haplotype P = 0.00004, based on 1,000,000 permutations). This association was independent of PSORS1. ADAM33 has been previously associated with asthma, which demonstrates that immune system diseases may be controlled by common susceptibility genes with general effects on dermal inflammation and immunity. The identification of ADAM33 as a psoriasis susceptibility gene identified by positional cloning in an outbred population should provide insights into the pathogenesis and natural history of this common disease
Evaluation of the association of heterozygous germline variants in NTHL1 with breast cancer predisposition: an international multi-center study of 47,180 subjects.
Bi-allelic loss-of-function (LoF) variants in the base excision repair (BER) gene NTHL1 cause a high-risk hereditary multi-tumor syndrome that includes breast cancer, but the contribution of heterozygous variants to hereditary breast cancer is unknown. An analysis of 4985 women with breast cancer, enriched for familial features, and 4786 cancer-free women revealed significant enrichment for NTHL1 LoF variants. Immunohistochemistry confirmed reduced NTHL1 expression in tumors from heterozygous carriers but the NTHL1 bi-allelic loss characteristic mutational signature (SBS 30) was not present. The analysis was extended to 27,421 breast cancer cases and 19,759 controls from 10 international studies revealing 138 cases and 93 controls with a heterozygous LoF variant (OR 1.06, 95% CI: 0.82-1.39) and 316 cases and 179 controls with a missense variant (OR 1.31, 95% CI: 1.09-1.57). Missense variants selected for deleterious features by a number of in silico bioinformatic prediction tools or located within the endonuclease III functional domain showed a stronger association with breast cancer. Somatic sequencing of breast cancers from carriers indicated that the risk associated with NTHL1 appears to operate through haploinsufficiency, consistent with other described low-penetrance breast cancer genes. Data from this very large international multicenter study suggests that heterozygous pathogenic germline coding variants in NTHL1 may be associated with low- to moderate- increased risk of breast cancer
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