AUTHOR=Alenezi Wejdan M. , Fierheller Caitlin T. , Serruya Corinne , Revil Timothée , Oros Kathleen K. , Subramanian Deepak N. , Bruce Jeffrey , Spiegelman Dan , Pugh Trevor , Campbell Ian G. , Mes-Masson Anne-Marie , Provencher Diane , Foulkes William D. , Haffaf Zaki El , Rouleau Guy , Bouchard Luigi , Greenwood Celia M. T. , Ragoussis Jiannis , Tonin Patricia N. 

TITLE=Genetic analyses of DNA repair pathway associated genes implicate new candidate cancer predisposing genes in ancestrally defined ovarian cancer cases

JOURNAL=Frontiers in Oncology

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2023.1111191

DOI=10.3389/fonc.2023.1111191

ISSN=2234-943X

ABSTRACT=<p>Not all familial ovarian cancer (OC) cases are explained by pathogenic germline variants in known risk genes. A candidate gene approach involving DNA repair pathway genes was applied to identify rare recurring pathogenic variants in familial OC cases not associated with known OC risk genes from a population exhibiting genetic drift. Whole exome sequencing (WES) data of 15 OC cases from 13 families tested negative for pathogenic variants in known OC risk genes were investigated for candidate variants in 468 DNA repair pathway genes. Filtering and prioritization criteria were applied to WES data to select top candidates for further analyses. Candidates were genotyped in ancestry defined study groups of 214 familial and 998 sporadic OC or breast cancer (BC) cases and 1025 population-matched controls and screened for additional carriers in 605 population-matched OC cases. The candidate genes were also analyzed in WES data from 937 familial or sporadic OC cases of diverse ancestries. Top candidate variants in <italic>ERCC5</italic>, <italic>EXO1</italic>, <italic>FANCC, NEIL1</italic> and <italic>NTHL1</italic> were identified in 5/13 (39%) OC families. Collectively, candidate variants were identified in 7/435 (1.6%) sporadic OC cases and 1/566 (0.2%) sporadic BC cases versus 1/1025 (0.1%) controls. Additional carriers were identified in 6/605 (0.9%) OC cases. Tumour DNA from <italic>ERCC5, NEIL1</italic> and <italic>NTHL1</italic> variant carriers exhibited loss of the wild-type allele. Carriers of various candidate variants in these genes were identified in 31/937 (3.3%) OC cases of diverse ancestries versus 0-0.004% in cancer-free controls. The strategy of applying a candidate gene approach in a population exhibiting genetic drift identified new candidate OC predisposition variants in DNA repair pathway genes.</p>