Association study of interleukin-12A gene polymorphisms with Graves' disease in two Chinese populations.
OBJECTIVE
Graves' disease (GD) is a common autoimmune disorder and genetic and environmental factors contributing to its aetiology. The pro-inflammatory cytokine interleukin-12 (IL-12) is believed to be critically involved in the pathogenesis of GD. This study aims to elucidate the effect of IL-12A gene polymorphisms on GD.


METHODS
A case-control association study of five tag single nucleotide polymorphisms (SNPs) (rs2243115, rs2243123, rs583911, rs568408 and rs2243143) within the IL-12A gene was performed in two independent Chinese cohorts. A pilot cohort conducted in Shanghai consisted of 701 patients and 686 controls and a replicate cohort in Xiamen Island included 378 patients and 312 controls. The five SNPs were genotyped by the SNPstream Genotyping Systems and Taqman PCR method.


RESULTS
Polymorphism of rs568408, located at the 3'-UTR region, was found to have a significant association with GD in both the cohorts (P(allele) = 2·96 × 10⁻⁷ and P(allele) = 0·013 for Shanghai and Xiamen Island cohorts, respectively). Haplotype analysis showed that the haplotype of the five SNPs (TTAAG) was associated with a significant risk of GD in both the cohorts (OR = 2·04 and OR = 1·70 for Shanghai and Xiamen Island cohorts, respectively).


CONCLUSIONS
Our results have established an association between IL-12A polymorphism and GD susceptibility in the Chinese population.
Shanghai Institutes for Biological Sciences, Shanghai JiaoTong University School of Medicine, China.
Ting
T
Guo
Shuyu
S
Yang
Nan
N
Liu
Shu
S
Wang
Bin
B
Cui
Guang
G
Ning
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D005260:Female; D005838:Genotype; D006111:Graves Disease / Q000235:genetics*; D006239:Haplotypes; D006801:Humans; D053765:Interleukin-12 Subunit p35 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D055815:Young Adult
D053765:Interleukin-12 Subunit p35