When the data were stratified according to specific gene mutations, alterations in MLH1, MSH2, MSH6, and PMS2 resulted in a cumulative prevalence at age 70 of 34%, 51%, 49%, and 24%, respectively, for endometrial cancer, and 11%, 15%, 0%, 0%, respectively, for ovarian cancer. The gene discussed is MSH2; the disease is endometrial cancer.