RESUMO
Pathogenic variants in BRCA1 and BRCA2 only explain the underlying genetic cause of about 10% of hereditary breast and ovarian cancer families. Because of cost-effectiveness, multigene panel testing is often performed even if the clinical utility of testing most of the genes remains questionable. The purpose of our study was to assess the contribution of rare, deleterious-predicted variants in DNA repair genes in familial breast cancer (BC) in a well-characterized and homogeneous population. We analyzed 113 DNA repair genes selected from either an exome sequencing or a candidate gene approach in the GENESIS study, which includes familial BC cases with no BRCA1 or BRCA2 mutation and having a sister with BC (N = 1,207), and general population controls (N = 1,199). Sequencing data were filtered for rare loss-of-function variants (LoF) and likely deleterious missense variants (MV). We confirmed associations between LoF and MV in PALB2, ATM and CHEK2 and BC occurrence. We also identified for the first time associations between FANCI, MAST1, POLH and RTEL1 and BC susceptibility. Unlike other associated genes, carriers of an ATM LoF had a significantly higher risk of developing BC than carriers of an ATM MV (ORLoF = 17.4 vs. ORMV = 1.6; p Het = 0.002). Hence, our approach allowed us to specify BC relative risks associated with deleterious-predicted variants in PALB2, ATM and CHEK2 and to add MAST1, POLH, RTEL1 and FANCI to the list of DNA repair genes possibly involved in BC susceptibility. We also highlight that different types of variants within the same gene can lead to different risk estimates.
Assuntos
Neoplasias da Mama/genética , Reparo do DNA/genética , Predisposição Genética para Doença , Testes Genéticos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Medição de Risco/métodos , IrmãosRESUMO
The genetic cause of some familial nonsyndromic renal cell carcinomas (RCC) defined by at least two affected first-degree relatives is unknown. By combining whole-exome sequencing and tumor profiling in a family prone to cases of RCC, we identified a germline BAP1 mutation c.277A>G (p.Thr93Ala) as the probable genetic basis of RCC predisposition. This mutation segregated with all four RCC-affected relatives. Furthermore, BAP1 was found to be inactivated in RCC-affected individuals from this family. No BAP1 mutations were identified in 32 familial cases presenting with only RCC. We then screened for germline BAP1 deleterious mutations in familial aggregations of cancers within the spectrum of the recently described BAP1-associated tumor predisposition syndrome, including uveal melanoma, malignant pleural mesothelioma, and cutaneous melanoma. Among the 11 families that included individuals identified as carrying germline deleterious BAP1 mutations, 6 families presented with 9 RCC-affected individuals, demonstrating a significantly increased risk for RCC. This strongly argues that RCC belongs to the BAP1 syndrome and that BAP1 is a RCC-predisposition gene.
Assuntos
Carcinoma de Células Renais/genética , Mutação em Linhagem Germinativa , Neoplasias Renais/genética , Mutação de Sentido Incorreto , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Adulto , Sequência de Bases , Carcinoma de Células Renais/enzimologia , Carcinoma de Células Renais/patologia , Exoma , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Neoplasias Renais/enzimologia , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Linhagem , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNARESUMO
Between January 1994 and December 2004, 696 patients with localized endometrial carcinoma have been treated at the Institute Jean-Godinot. Patients were selected on the following criteria: histologically proven adenocarcinoma of the endometrium; age at onset under 60 years; patient not deceased at the time of the study. One hundred twelve patients met these criteria and received a mailed specific questionnaire to establish their pedigree. Thirty-one patients (35.5%) were eventually found eligible for a genetic counselling but only 13 patients agreed to be informed later on. According to the obtained pedigrees and MSI test results, 7 genetic tests have been carried out and so far, 3 MMR mutations were detected. This study suggested the feasibility of a step by step screening of endometrial cancers to select patients at risk for Lynch syndrome and for whom a genetic test would be recommended. Authors suggest that either Amsterdam or Bethesda criteria should be systematically used prospectively in every newly diagnosed endometrial cancer and retrospectively using clinical databases available on endometrial cancers.