Whole exome sequencing identifies FANCM as a susceptibility gene for estrogen-receptor-negative breast cancer in Hispanic/Latina women.

Breast cancer (BC) is one of the most common cancers globally. Genetic testing facilitates screening and informs targeted risk-reduction and treatments. However, genes included in testing panels are from European-ancestry studies. We conducted a pooled case-control analysis in self-identified Hispanic/Latina women (4178 cases and 4344 controls), using whole exome sequencing and a targeted panel. We tested the association of loss of function (LoF) variants with overall, estrogen receptor (ER)-positive, and ER-negative BC risk. Using logistic regression, we found a strong association of LoF variants in FANCM with ER-negative BC (p = 4.1 × 10-7), odds ratio [confidence interval]: 6.7 [2.9-15.6]). Among known susceptibility genes, BRCA1, BRCA2, and PALB2 strongly associated with BC. FANCM was previously proposed as a possible susceptibility gene for ER-negative BC, but is not routinely tested clinically. Our results demonstrate that FANCM should be added to BC gene panels.