The primary objective of this research is to determine whether DNA hypermethylation is a biomarker that will predict which patients with BE are likely to progress to adenocarcinoma. Patients with BE and/or esophageal adenocarcinoma who undergo endoscopy at the Johns Hopkins Hospital will comprise the cohort of subjects. Gene hypermethylation will be assessed by performing methylation-specific PCR on a panel of 8 cancer-related genes.