Our results showed that SNPs rs2227982 and rs10204525 were interrelated to AAU; the influence on AAU could be related with gender, HLA-B27, and AS stat</span>us.
The frequency of the CT haplotype (PD-1 rs2227981 C allele and PD-1 rs2227982 T allele) was higher in the AS patient group comparing with the controls (odds ratio (OR)=1.845, 95% confidence interval 1.220-2.789).