PALB2 and ovarian cancer: Except for high-penetrance (high-risk) BRCA alleles, several low-penetrance (low-risk) alleles could account for the increased risk of ovarian cancer, including mutations in BRCA1-interacting helicase 1 (BRIP1), RAD51 Paralog C (RAD51C), RAD51D, and partner and localizer of BRCA2 (PALB2) genes, with the odds ratio of ovarian cancer being 14.1 for BRIP1, 5.2 for RAD1C, and 12.0 for RAD1D mutation and a relative risk of 2.9 for PALB2, respectively [16,17].