title: A haplotype in STAT4 gene associated with rheumatoid arthritis in Caucasians is not associated in the Han Chinese population, but with the presence of rheumatoid factor.
abstract: OBJECTIVE
  Several studies have shown that a haplotype (rs11889341, rs7574865, rs8179673 and rs10181656) in STAT4 is associated with the development of RA in Caucasian, Korean and Japanese populations. The aim of this study was to investigate the effect of STAT4 on susceptibility to RA in the Han Chinese population.
  
  
  METHODS
  Unrelated 750 RA patients and individually matched 750 healthy controls were genotyped for single nucleotide polymorphism (SNP), rs11889341, in STAT4, which tags the susceptibility haplotype. Association analyses were performed on the whole data set and on sex subsets. Significant relationships were determined between clinical variables and rs11889341 for each disease subtype in the studied groups.
  
  
  RESULTS
  There was no evidence of a significant association between rs11889341 and RA. The heterozygous CT genotype was associated with RA in female group [P = 0.027; odds ratio (OR) 1.31; 95% CI 1.03, 1.65]. No association was found in male group and in any subsets of RA based on sex, RF and anti-cyclic citrullinated peptide (anti-CCP) antibody. However, in the Han Chinese population with RA disease, we observed a significantly decreased frequency of the minor T allele and TT genotype in the RF-positive subgroup compared with RF-negative subgroup (T allele: P = 0.024; OR 0.73; 95% CI 0.56, 0.95; TT genotype P = 0.013; OR 0.49; 95% CI 0.28, 0.86).
  
  
  CONCLUSIONS
  The STAT4 RA-susceptibility haplotype identified in other previously reported populations has not been replicated in the Han Chinese population with individually matched case-control study design. It is associated only with the presence of RF in the Han Chinese population with RA disease.
authors.affiliation: Institute of Immunology of PLA, College of Basic Medical Sciences in the Third Military Medical University, Chongqing, 400038, PR China.
authors.forename: Hua
authors.initials: H
authors.lastname: Li
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zou
authors.forename: Zhunyi
authors.initials: Z
authors.lastname: Xie
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Bing
authors.initials: B
authors.lastname: Zhong
authors.forename: Shu
authors.initials: S
authors.lastname: Yang
authors.forename: Ping
authors.initials: P
authors.lastname: Zheng
authors.forename: Fei
authors.initials: F
authors.lastname: Yang
authors.forename: Yongfei
authors.initials: Y
authors.lastname: Fang
authors.forename: YuZhang
authors.initials: Y
authors.lastname: Wu
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000208:ethnology / Q000235:genetics* / Q000276:immunology; D044466:Asian People / Q000235:genetics; D001323:Autoantibodies / Q000097:blood; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D012217:Rheumatoid Factor / Q000097:blood*; D050797:STAT4 Transcription Factor / Q000235:genetics*
chemical_list: D001323:Autoantibodies; D010456:Peptides, Cyclic; D050797:STAT4 Transcription Factor; C494090:STAT4 protein, human; C487763:cyclic citrullinated peptide; D012217:Rheumatoid Factor