MSH2 and polymyositis: In the Okada et al study[14], two DNA mismatch repair enzymes, Homo sapiens mutS homolog 2 (hMSH2) and Homo sapiens postmeiotic segregation increased 1 (hPMS1) were found to over-express in pancreatic ductal adenocarcinoma, and their antibodies were detected in sera from patients with pancreatic ductal adenocarcinoma, and in sera from patients with polymyositis, but not in sera from healthy individuals.