This domain is found in proteins of the MutS family (DNA mismatch repair proteins) and is found associated with pfam01624, pfam05188, pfam05192 and pfam05190. The mutS family of proteins is named after the Salmonella typhimurium MutS protein involved in mismatch repair; other members of the family included the eukaryotic MSH 1,2,3, 4,5 and 6 proteins. These have various roles in DNA repair and recombination. Human MSH has been implicated in non-polyposis colorectal carcinoma (HNPCC) and is a mismatch binding protein. The aligned region corresponds with domain V of Thermus aquaticus MutS, which contains a Walker A motif, and is structurally similar to the ATPase domain of ABC transporters.