title: Interleukin-17F gene polymorphism in patients with chronic immune thrombocytopenia.
abstract: BACKGROUND
  IL-17F is a novel inflammatory cytokine and plays an important role in some autoimmune diseases. We investigated the association between chronic ITP and the frequency of the single-nucleotide polymorphism rs763780 (7488T/C), which causes a His-to-Arg substitution at amino acid 161.
  
  
  METHODS
  We examined 102 patients (men/women, 40/62; median age, 42) diagnosed with chronic ITP and 188 healthy controls (men/women, 78/110; median age, 38). Genotyping was determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique.
  
  
  RESULTS
  Compared with the control group, patients with chronic ITP had a significantly lower frequency of the IL-17F 7488CC genotype (0% vs. 4.8%, P<0.05). The number of IL-17F 7488C alleles among the patients with chronic ITP was also significantly lower than in the control group (8.7% vs. 15.2% OR=0.48, 95%CI=0.27-0.84, P=0.016). Furthermore, patients with the IL-17F 7488TT genotype showed a severe thrombocytopenic state (platelet count<10×10(9) /L) at diagnosis than those with the IL-17F 7488TC genotype (20.9% vs. 0%, P=0.04).
  
  
  CONCLUSIONS
  These findings suggest that the IL-17F 7488 T allele is significantly associated with the development of chronic ITP, suggesting a role for IL-17F in the pathogenesis of chronic ITP.
authors: Onclology Center, Gunma University Hospital Department of Medicine and Clinical Science, Gunma University Graduate School of Medicine, Showa-machi 3-39-15, Maebashi, Gunma, Japan. tsaitoh@showa.gunma-u.ac.jp
authors: Takayuki
authors: T
authors: Saitoh
authors: Norifumi
authors: N
authors: Tsukamoto
authors: Hiromi
authors: H
authors: Koiso
authors: Takeki
authors: T
authors: Mitsui
authors: Akihiko
authors: A
authors: Yokohama
authors: Hiroshi
authors: H
authors: Handa
authors: Masamitsu
authors: M
authors: Karasawa
authors: Hatsue
authors: H
authors: Ogawara
authors: Yoshihisa
authors: Y
authors: Nojima
authors: Hirokazu
authors: H
authors: Murakami