Objective: The aim of this study was to determine whether genetic polymorphisms in programmed cell death 1 (PDCD1 or PD1) are associated with susceptibility to rheumatoid arthritis (RA), ankylosing spondylitis (AS), and type 1 diabetes (T1D).
Methods: We conducted a meta-analysis to investigate the association between PDCD1 polymorphisms and RA, AS, and T1D in the overall population and in specific ethnic populations.
Results: Sixteen studies, comprising 13,210 patients and 17,073 controls, were conducted for the meta-analysis including 4 studies on RA, 4 on AS, and 8 on T1D. The meta-analysis showed an association between RA and the 2 alleles of the PD1.3 polymorphism in the overall population [odds ratio (OR) 1.183, 95 % confidence interval (95 % CI) 1.005-1.392, p = 0.043]. However, meta-analysis showed no association between RA and the 2 alleles of the PD1.1 and PD1.5 polymorphisms in the overall population. Meta-analysis identified an association between AS and the 2 alleles of the PD1.5 and PD1.9 polymorphisms in the Asian population (OR 1.251, 95 % CI 1.019-1.535, p = 0.033; OR 1.975, 95 % CI 1.286-3.034, p = 0.002, respectively). The meta-analysis revealed a significant association between T1D and the 2 alleles of the PD1.3 polymorphism in the European population (OR 1.098, 95 % CI 1.029-1.171, p = 0.005). The meta-analysis showed an association between the PD1.5 polymorphism and T1D in Asians (OR 1.332, 95 % CI 1.067-1.663, p = 0.011) and between the PD1.9 polymorphism and T1D in the Asian population (OR 1.363, 95 % CI 1.107-1.679, p = 0.004).
Conclusion: The meta-analysis suggests an association between the PD1.3 polymorphism and RA in the overall population and an association between the PD1.5 and PD1.9 polymorphisms, and AS in the Asian population. Furthermore, the PD1.3 , 5, and 9 polymorphisms were associated with T1D susceptibility in Europeans, or Asians.