Although no samples from GERD patients with LOH at the TS locus were observed in the lower esophageal mucosa (0/22 samples)), 6 out of 21 samples (28.6%) had LOH in IM, 2 out of 7 (28.6%) in dysplasia, and 10 out of 25 (40.0%) in BA. The gene discussed is TYMS; the disease is dysplasia.