Purpose Polymorphisms of the il21-il2 gene have recently been identified to be associated with the risk to several immune diseases. The aim of this study was to determine the potential association of il2-il21gene polymorphisms with BD

Methods A total of 600 Han Chinese patients with BD and 1000 healthy controls were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Genotype counts in patients and controls were analyzed by the x² test.

Results All genotypic and allelic frequencies of the tested four il2-il21 polymorphisms were in Hardy-Weinberg equilibrium. The genotypic and allelic frequencies of rs11938795、rs907715、rs2221903 and rs6822844 were not different between patients with BD and controls. No influence of sex could be found following stratification analysis according to gender.

Conclusions Our results suggest that the investigated four SNPs, rs11938795、rs907715、rs2221903 and rs6822844 , in il2-il21gene are not associated with BD in the Han Chinese population.