Association of GSTT1, GSTM1 and CYP1A1 polymorphisms with susceptibility to systemic lupus erythematosus in the Chinese population

BackgroundGSTT1, GSTM1, CYP1A1 are enzymes responsible for the detoxification of the toxicant which may be involved in the development of systemic lupus erythematosus (SLE). We examined the relationship between the risk of SLE and the polymorphisms of these genes in the Chinese population.MethodsSamples from 298 SLE patients and 284 healthy controls were collected. Polymerase chain reaction-restriction fragments length polymorphism (PCR–RFLP) was used to analyze the genotypes of CYP1A1 m2 and m4, while multiplex PCR was used to analyze the genotypes of GSTT1 and GSTM1.ResultsStatistically significant difference was observed in genotypes for GSTM1 (p = 0.003, OR 1.66 [95% CI 1.19–2.32]), but not for GSTT1 (p = 0.119, OR 0.77 [95% CI 0.56–1.07]), in the SLE patients as compared with the controls. Combinational analysis for double-null deletion of both GSTT1 and GSTM1 showed no significant difference (p = 0.863, OR 1.03 [95% CI 0.70–1.52]). Significant difference was observed in the genotype frequencies (p = 0.013), but not in the allele frequencies (p = 0.444, OR 0.90 [95% CI 0.70–1.17]), of CYP1A1 m2. All candidates have a wild-type genotype for CYP1A1 m4.ConclusionsPolymorphisms of GSTM1 are associated with SLE in the Chinese population.