Connection of COX-2 variants to ankylosing spondylitis susceptibility

This study aimed to explore the associations of COX-2 polymorphisms rs5275, rs20417, and rs2745557 with the susceptibility to ankylosing spondylitis among Chinese Han people. Polymerase chain reaction-restriction fragment length polymorphism (PCR/RFLP) was adopted for genotyping COX-2 polymorphisms rs5275, rs20417, and rs2745557 among 109 AS patients and 122 healthy controls. Genotype distribution in the control group was examined for these three polymorphisms to test whether it conformed to Hardy-Weinberg equilibrium (HWE) expectation. A χ² -test was employed to compare genotype and allele frequencies between the two groups. Besides this, logistic regression analyses were also performed to adjust age and gender. A p less than .05 represented a significant level. Genotype distribution of our studied polymorphisms showed fine conformity to HWE in the controls. An increasing effect on AS risk was detected for the polymorphism rs5275 under GG versus AA contrast (crude: OR, 3.040; 95% CI, 1.015-9.104), and the adjustment for age and gender did not change such a relationship (adjusted OR, 3.307; 95% CI, 1.065-10.268). After adjusting age and gender, both polymorphisms of rs20417 and rs2745557 demonstrated a negative relationship with the disease susceptibility. The GC genotype and C allele of rs20417 reduced the disease risk to 0.248 (adjusted: 95% CI, 0.089-0.692) and 0.269 (95% CI, 0.098-0.733), respectively, while the AA genotype and A allele of the latter to 0.413 (adjusted: 95% CI, 0.191-0.893) and 0.676 (adjusted: 95% CI, 0.466-0.981), respectively. Among Chinese Han people, COX-2 polymorphism rs5275 may contribute to increased risk of developing AS, while the polymorphisms rs20417 and rs2745557 may offer protection against disease incidence.