The focus of the laboratory is upon studies of DNA damage and genomic instability in aging and in neoplastic progression. In aging, we are interested in the connection between DNA damage and free radical injury and lifespan and disease. Transgenic mice that overexpress antioxidant enzymes have enhanced longevity and are being examined to provide insights in this model system. Studies of neoplastic progression focus on human gastrointestinal cancers and precancerous diseases such as Barrett's esophagus and Ulcerative Colitis. A better understanding of neoplastic progression in these diseases may yield biomarkers of increased clinical risk for progression to cancer. Genomic instability has proven to be one such a marker. In both aging and neoplasia, we are interested in the role of telomere shortening in promoting genomic instability.