STK11 and breast cancer: We further identified 340 variants in other known predisposition genes of ATM, BARD1, BRIP1, CDH1, CHEK2, MRE11A, MUTYH, NBN, NF1, PALB2, PTEN, RAD50, RAD51C, RAD51D, STK11, and TP53. Six variants were identified in BRIP1, MRE11A, NBN, PTEN, TP53, of which only one in NBN (chr8:90990521T>C, NM_002485, c.A511G, p.I171V) was predicted as deleterious by both SIFT and Polyphen2 programs and classified as pathogenic by ClinVar database but this variant was present only in one breast cancer-affected case (member 2 in Family 3).