Article
Author: Suzuki, Seiyuu ; Andoh, Akira ; Kato, Hiromasa ; Hiraoka, Sakiko ; Nunoi, Hiroaki ; Ikeda, Yoshio ; Hiasa, Yoichi ; Hato, Naohito ; Miyake, Teruki ; Imaeda, Hirotsugu ; Miyake, Yoshihiro ; Kawasaki, Keitarou ; Miura, Hiromasa ; Okada, Hiroyuki ; Tanaka, Keiko ; Yoshimura, Naoki ; Ninomiya, Tomoyuki ; Mizukami, Yuji ; Takeshita, Eiji ; Hokari, Ryota ; Nagata, Chisato ; Higashiyama, Masaaki ; Furukawa, Shinya ; Yamamoto, Yasunori ; Saito, Mitsuru ; Kakimoto, Kazuki ; Yokoyama, Tetsuji ; Higuchi, Kazuhide ; Ohashi, Katsuhisa ; Mori, Kenichiro ; Kumagi, Teru ; Sayama, Koji
BACKGROUNDInterleukin (IL)-23 is involved in the pathogenesis of ulcerative colitis (UC). A genome-wide significant association between IL23R p.G149R (rs76418789) and UC was previously identified in Japan and Korea. This case-control study aims to examine this association within the Japanese population.METHODSThe study included 384 cases diagnosed with UC within the past 4 years and 661 control subjects. Adjustment was made for sex, age, and smoking.RESULTSThe frequency of the AA genotype of rs76418789 was 0.0 % in cases and 0.5 % in control subjects. In comparison to study subjects with the GG genotype of rs76418789, those with the GA or AA genotype had a significantly reduced risk of UC, with an adjusted odds ratio of 0.67 (95 % confidence interval: 0.44-0.999). A significant multiplicative interaction was observed between rs76418789 and having ever smoked influencing UC (p for interaction = 0.03). A significant positive association was found between having ever smoked and UC in individuals with at least one A allele, while no such positive relationship was observed in those with the GG genotype.CONCLUSIONIL23R SNP rs76418789 showed a significant association with UC. This study provides new evidence regarding the interaction between rs76418789 and smoking in relation to UC.