We simultaneously measured DNA content abnormalities (tetraploidy and aneuploidy), inactivation of TP53 (mutation and LOH), and inactivation of CDKN2A (mutation, methylation, and LOH), all of which have been shown to be mechanistically related to neoplastic progression in BE [28,29,34,80–82]. This evidence concerns the gene CDKN2A and Barrett esophagus.