This study was designed to evaluate the association of these SNPs rs2910164 in pre-miR-146a, rs4541843 in pri-miR-182, rs3746444 in pre-miR-499, rs12975333 in pre-miR-125a, and rs2043556 in miR-605 with familial BC and early-onset non-familial BC in non-carriers of BRCA1/2 mutations from a South American population. Here, BRCA1 is linked to breast cancer.