In the present study, we have investigated the prevalence of core genetic (TP53 mutations and MSI status) and epigenetic (DNA promoter hypermethylation of APC, CDKN2A, MGMT, TIMP3 and MLH1) modifications in a cohort of non-dysplastic BE and a large series of EAC samples. The gene discussed is MLH1; the disease is Barrett esophagus.