The remaining hereditary breast and ovarian cancer cases are associated with mutations in other breast and ovarian cancer susceptibility genes, such as BRCA1/2, TP53, PTEN, CDH1, STK11, MLH1, MSH2, MSH6, PMS2, PALB2, CHEK2, ATM, RAD51C, RAD51D, BRIP1 and other [9]. This evidence concerns the gene MSH2 and ovarian cancer.