Distribution of clones at the genus level. A: Normal subjects. B: Patients with reflux esophagitis. C: Patients with Barrett’s esophagus. Genus-level distribution of clones in patients with a normal esophagus, reflux esophagitis and Barrett’s esophagus is shown. Veillonella was the most prevalent genus in patients with Barrett’s esophagus. Fusobacterium was not found in patients with a normal esophagus.