Association of a Single Nucleotide Polymorphism of IL-21 Gene with Asthma in a Chinese Han Population
Author(s): Jing Lin and Guangre Xu
Autoimmune abnormalities appear to be major predisposing factors for asthma. Rs12508721 and rs2055979 of interleukin-21
(IL-21) gene polymorphisms have been previously found to be associated with autoimmune diseases. This study aimed to assess the role of
IL-21 in asthma in a Chinese Han population.
Method: A total of 199 independent asthma patients and 249 unrelated healthy controls were recruited for this case-control association study.
Two SNPs (rs12508721 and rs2055979) were genotyped by PCR-RFLP.
Results: The allele T frequency of rs12508721 was significantly higher in asthma patients than in controls (OR=1.58, 95% CI=1.18-2.11,
P=0.0021). The effect of dominant model (CC versus CT + TT, OR=.83, 95CI=1.24-2.69, P=0.0021) was observed. Distributions of allele
and genotype frequencies of the SNP rs2055979 showed no signiﬁcant differences between asthma patients and controls.
Conclusion: Our findings suggest that polymorphism of IL-21 gene plays an important role in susceptibility to asthma in a Chinese Han