1. IL18 polymorphism is associated with an increased risk of Crohn's disease
- Author
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Yoshihiro Yamamoto, Takehira Yamamura, Kazuo Tamura, Shin Fukui, Takashi Shimoyama, Masamichi Satomi, Koji Sawada, Hiroko Bamba, Haruki Okamura, Takahiro Yamada, Tadashi Kosaka, Hiroko Sashio, Yoshihiro Fukuda, Naohisa Takeda, K. Tamura, and Jun-ichi Furuyama
- Subjects
Adult ,Male ,Adolescent ,Genotype ,Molecular Sequence Data ,Single-nucleotide polymorphism ,Disease ,Inflammatory bowel disease ,Polymerase Chain Reaction ,Risk Assessment ,Sensitivity and Specificity ,Sampling Studies ,Proinflammatory cytokine ,Pathogenesis ,Age Distribution ,Crohn Disease ,Reference Values ,medicine ,Genetic predisposition ,Confidence Intervals ,Odds Ratio ,Humans ,Genetic Predisposition to Disease ,Sex Distribution ,Aged ,Probability ,Crohn's disease ,Polymorphism, Genetic ,Base Sequence ,business.industry ,Incidence ,Gastroenterology ,Interleukin-18 ,Middle Aged ,medicine.disease ,Ulcerative colitis ,digestive system diseases ,Case-Control Studies ,Immunology ,Colitis, Ulcerative ,Female ,business - Abstract
Background. The etiology of inflammatory bowel disease, which includes ulcerative colitis and Crohn’s disease, has not yet been made clear. However, inflammatory bowel disease is recognized as a multifactorial disease, and innate genetic factors might contribute to the pathogenesis. Cytokine genes are thought to be important in inflammatory bowel disease. Recently, interleukin 18, cloned as a novel proinflammatory cytokine, has been implicated in inflammatory bowel disease, especially Crohn’s disease. Methods. To identify germline mutations in patients with inflammatory bowel disease, the entire coding region of IL18 was examined using a DNA sequencing procedure. Results. No functional mutations were found, but a novel single nucleotide polymorphism (SNP) was identified as TCA/ TCC at codon 35. In patients with Crohn’s disease, the frequency of TCC allele carriers was significantly higher than in healthy controls (χ2 = 9.35, P = 0.002229, OR = 2.58, 95% CI = 1.39–4.80). Also, the magnitude of the association was more remarkable in females (χ 2 = 16.36, P = 0.000052, OR = 8.17, 95% CI = 2.73–24.41). The TCC allele at codon 35 of IL18 may increase the risk for Crohn’s disease, especially in females. Conclusions. IL18 is probably one of several genes that determine susceptibility to Crohn’s disease.
- Published
- 2003