dbMMR-Chinese database: the first public database of DNA mismatch repair gene variation in Chinese population

Mutation in DNA mismatch repair genes (MMR) is the genetic predisposition for multiple types of cancer as represented by the Lynch syndrome. Identification of MMR mutation carrier without cancer is critical for their cancer prevention and these with cancer for effective treatment. China has the largest population size and the largest cancer cases in the world. However, comprehensive MMR mutation knowledge in this population remains elusive. We performed an extensive data mining, standardization, and annotation for MMR variation data derived from 53,917 Chinese individuals, including 25,013 cancer cases and 28,904 non-cancer cases. We identified 21,376 distinct MMR variants including 1,894 in coding regions and19,482 in non-coding regions in four MMR genes of MLH1, MSH2, MSH6 and PMS2. Using the data, we developed an open-access public database dbMMR-Chinese (https://dbMMR-chinese.fhs.um.edu.mo), which is the largest one from a single non-Caucasian ethnic population.