The purpose of this study is to determine or evaluate the risk factors such as smoking, family history etc. that cause esophageal cancer and to determine the genetic changes that lead to esophageal cancer. The investigators hypothesis is that systematic collection of data on the natural history of GERD and BE patients and risk factors for development of BE in patients with chronic GERD and progression of BE to dysplasia and adenocarcinoma will provide useful information to develop a decision model for risk stratification and risk reduction strategies in these patients.