e tested whether polymorphic variations in glutathione S-transferase genes (GSTM1, GSTT1, GSTP1) and interleukin-1 (IL-1beta and IL-1RN) genes confer susceptibility to mucosa-associated lymphoid tissue lymphomas (MALT) in a Chinese population. The rates of GSTM1, GSTP1, IL-1beta and IL-1RN genotypes did not differ between patients and controls. However, GSTT1 null genotypes were significantly more common in patients with MALT lymphomas (43/75 vs. 138/321, p=0.029; OR=1.8, 95% CI: 1.1-3.0) than in controls. Our results suggest that a glutathione S-transferase defect plays a role in MALT lymphoma.