Abstract A44: The identification of germline mutations in DNA repair genes in Brazilian individuals at-risk for hereditary breast cancer

Hereditary breast cancer corresponds to 10-15% of all diagnosed cases of breast cancer in the world. The majority germline mutations are identified in BRCA1/2 genes, however the application of multigene panels has increased the number of pathogenic variations detected in DNA repair genes. According to the current version of NCCN Guideline, mutations in BRCA1/2, TP53 and PTEN confers high risk to develop breast cancer, and mutations in CDH1, CHEK2, PALB2, ATM and BRIP can increases over than 20% this risk. We analyzed 157 individuals from Northeastern region of Brazil with personal and/or familial breast cancer history. Genomic DNA was isolated from peripheral blood through saline-based extraction and samples were analyzed using next-generation sequencing (NGS). We identified 15 pathogenic variants and 4 VUS (Variants of Uncertain Significance) in 27 individuals (27/157; 17%), in which three are asymptomatic. Six novel variants in 4 genes were identified: BRCA1_c.3409A>G; BRCA2_c.5800C>T; BRCA2_c.5228G>A; BRCA2_c.5305delG; ATM_c.634delT and ATR_c.3043C>T. Sixty-eight percent (13/19; 68%) of variants was detected in BRCA1/2 genes, while 32% (6/19) were identified in moderate risk genes ATM (2/19); ATR (1/19); CDH1 (1/19); MLH1 (1/19) and MSH6 (1/19). The individuals were separated in two groups for comparative analysis: high-risk genes and moderate risk genes. Among three asymptomatic individuals, two present variants in moderate risk genes ATM and MLH1. Among breas...
Source: Molecular Cancer Research - Category: Cancer & Oncology Authors: Tags: Other Topics: Poster Presentations - Proffered Abstracts Source Type: research