While the prevalence of endometrial cancer in women (68/167, 41 %) was similar in both groups (36 vs. 44 %), other extracolonic cancers were more frequent in MSH2 carriers compared to MLH1 carriers (24 vs. 9 %; OR 3.2; 95 % CI 1.5–6.6; P = 0.001) and their families (P<0.001). The gene discussed is MLH1; the disease is endometrial cancer.