Epigenetic alteration of mismatch repair genes in the population chronically exposed to arsenic in West Bengal, India

A case-control study was designed to analyze the methylation status of key MMR genes i.e. MLH1, MSH2, and PMS2 using methylation-specific PCR (MSP) and their gene expression alterations by qRTPCR in arsenic exposed population. The expression of H3K36me3, an important regulator of MMR pathway, was found to be down regulated by ELISA based assay. This might hinder the efficient recruitment of MMR proteins at the site of DNA mismatches. The promoter of both MLH1, MSH2 was found to be hypermethylated with consequent down regulated expression pattern. Theses altogether indicate compromised MMR pathway in arsenic exposed population.215