Mutation screening of MIR146A/B and BRCA1/2 3'-UTRs in the GENESIS study.
Fiche publication
Date publication
août 2016
Journal
European journal of human genetics : EJHG
Auteurs
Membres identifiés du Cancéropôle Est :
Pr FAIVRE Laurence
Tous les auteurs :
Garcia AI, Buisson M, Damiola F, Tessereau C, Barjhoux L, Verny-Pierre C, Sornin V, Dondon MG, Eon-Marchais S, , Caron O, Gautier-Villars M, Coupier I, Buecher B, Vennin P, Belotti M, Lortholary A, Gesta P, Dugast C, Noguès C, Fricker JP, Faivre L, Stoppa-Lyonnet D, Andrieu N, Sinilnikova OM, Mazoyer S
Lien Pubmed
Résumé
Although a wide number of breast cancer susceptibility alleles associated with various levels of risk have been identified to date, about 50% of the heritability is still missing. Although the major BRCA1 and BRCA2 genes are being extensively screened for truncating and missense variants in breast and/or ovarian cancer families, potential regulatory variants affecting their expression remain largely unexplored. In an attempt to identify such variants, we focused our attention on gene regulation mediated by microRNAs (miRs). We screened two genes, MIR146A and MIR146B, producing miR-146a and miR-146b-5p, respectively, that regulate BRCA1, and the 3'- untranslated regions (3'-UTRs) of BRCA1 and BRCA2 in the GENESIS French national case/control study (BRCA1- and BRCA2-negative breast cancer cases with at least one sister with breast cancer and matched controls). We identified one rare variant in MIR146A, four in MIR146B, five in BRCA1 3'-UTR and one in BRCA2 3'-UTR in 716 index cases and 619 controls. Among these 11 rare variants, 7 were identified each in 1 index case. None of the three relevant MIR146A/MIR146B variants affected the pre-miR sequences. The potential causality of the four relevant BRCA1/BRCA2 3'-UTRs variants was evaluated with luciferase reporter assays and co-segregation studies, as well as with bioinformatics analyses to predict miRs-binding sites, RNA secondary structures and RNA accessibility. This is the first study to report the screening of miR genes and of BRCA2 3'-UTR in a large series of familial breast cancer cases. None of the variant identified in this study gave convincing evidence of potential pathogenicity.
Mots clés
3' Untranslated Regions, Adult, Aged, BRCA1 Protein, genetics, BRCA2 Protein, genetics, Breast Neoplasms, genetics, Case-Control Studies, Female, HeLa Cells, Humans, MCF-7 Cells, MicroRNAs, genetics, Middle Aged, Mutation
Référence
Eur. J. Hum. Genet.. 2016 08;24(9):1324-9