['Non-steroidal anti-inflammatory drugs (NSAIDs) aggravate or ameliorate clinical disease activity in patients with ulcerative colitis (UC). UC is associated with increased local production of prostanoids. This study attempted to clarify the relationship between cyclooxygenase-1 (COX1) gene polymorphisms (T-1676C and A-842G/C50T) and ulcerative colitis in a Japanese population.', 'The study was performed on 108 patients with UC (mean age: 39.1 years, M:F=56:52) and 293 healthy controls (mean age: 49.0 years, M:F=161:132). The PCR-SSCP method was employed to detect COX1 polymorphisms using DNA extracted from peripheral blood cells.', 'No A-842G/C50T polymorphism was detected in all 401 Japanese subjects. The frequency of -1676C allele of COX1 gene in HC group and UC group was 48.8% and 48.1%, respectively. T-1676C genotypes of COX1 did not show significant association with UC risk. In addition, these genotypes were not also associated with the clinicopathological parameters of UC.'] Is promoter polymorphism of cyclooxygenase-1 ( COX1 ) associated with ulcerative colitis in the Japanese population?