摘要AIM: To investigate whether Recql5, a DNA helicase that plays an important role in the maintenance of genome integrity, is a tumor suppressor in the gastrointestinal tract in mice. METHODS: We generated cohorts of both Recql5-pro- ficient and Recql5-deficient Apc~(min)/+ mice and compared the tumor susceptibility in their gastrointestinal tracts. RESULTS: Recql5 deficiency in Apc~(min/+) mice resulted in a significant increase in the tumor incidence in both the colon (P=0.0162) and the small intestine (P<0.01). These findings have provided the first genetic evidence for a tumor suppression role of Recql5 in the gastrointestinal tract of mice. Importantly, since mouse Recql5 and human RECQL5 are highly conserved, these findings also suggest that RECQL5 may be a tumor suppressor for human colon cancer. CONCLUSION: Recql5 has a tumor suppression role in the mouse gastrointestinal tract.