Abstract: Isolated mucosal epithelial cells derived front with gastric cancer from high and low incidence surgically resected human stomach areas in Fujian studied. Following maintenance in short-term culture in vitro, the province were mucosal tissue was exposed to ultraviolet for 25 minutes and then cultured in the presence TdR and hydrourea, The unscheduled DNA synthesis (UDS) was assessed by of(aH) using hydrosylapatite the cpm/ug DNA column chromatograph and liquid scintillation was In present study, determined the DNA as an indirect measure repair ability in gastric of DNA mucosal counting set, and damage repair. cells in high inci- dence This area group is significantly lower than that in low may play part of the role in the inducing of gastric incidence area group, cancer