Esteller et al. (2001) have demonstrated the reduced expression of tumour suppressor genes such as p16, MGMT, and hMLH1 by promoter hypermethylation in several human neoplasias, and have suggested that this epigenetic change might be an early event in the pathogenesis of several human tumours. Recently, the correlation of p16 promoter hypermethylation with chronic hepatitis and cirrhosis associated with HBV or HCV infection has been reported (Kaneto et al, 2001). This evidence concerns the gene MLH1 and neoplasm.