Thus, from the 193 final candidate variants, we selected 23 candidate genes of BC predisposition: 7 novel candidate genes segregating in the 3 members of the MJ2007/2012 family (SLC22A16, ROS1, IL33, PTPRD, ARHGEF12, ERBB2, POLA1), five cancer-related genes harboring LOF variants (GALNT3, RAF1, PICALM, KL, ERCC1) and 12 genes overlapping with candidate genes identified in other studies (CAPN9, KRT76, PZP, DNAH7, MST1R, LAMB4, NIN, MSH3, SLX4, DDX1, NOTCH2, and ROS1—ROS1 was also selected in the segregating genes list). This evidence concerns the gene ARHGEF12 and breast cancer.