Yanagawa T, Maruyama T, Gomi K, Taniyama M, Kasuga A, Ozawa Y, Terauchi M, Hirose H, Maruyama H, Saruta T
Department of Medicine, Nerima General Hospital, Tokyo, Japan.
Autoimmunity. 1999;29(1):53-6. doi: 10.3109/08916939908995972.
Susceptibility to insulin-dependent diabetes mellitus (IDDM) is determined by both environmental and genetic factors. The main gene associated with predisposition to IDDM is HLA. Recent studies have described linkage and association of IDDM to the CTLA-4 gene (IDDM12) in Caucasians. CTLA-4 is a candidate gene for T-cell-mediated autoimmune diseases because it is a negative regulator of T-cell proliferation. We investigated the distribution of a CTLA-4 gene polymorphism in 110 Japanese patients with IDDM and 200 control subjects. In 84 patients, we also investigated associations between this CTLA-4 gene polymorphism and GAD65 antibody positivity. An A/G transition at position 49 of exon 1 was analyzed by the polymerase chain reaction-restriction fragment length polymorphism method. GAD65 antibody was detected using a radioligand binding assay. There was no significant difference in the distribution of CTLA-4 alleles in patients and controls and no difference was observed in prevalence of CTLA-4 alleles when GAD65 antibody-positive and -negative individuals in the IDDM groups were compared. The present study did not support an association between the CTLA-4 gene and IDDM in the Japanese population.
胰岛素依赖型糖尿病（IDDM）的易感性由环境和遗传因素共同决定。与IDDM易感性相关的主要基因是HLA。最近的研究描述了白种人中IDDM与CTLA-4基因（IDDM12）的连锁和关联。CTLA-4是T细胞介导的自身免疫性疾病的候选基因，因为它是T细胞增殖的负调节因子。我们调查了110名日本IDDM患者和200名对照者中CTLA-4基因多态性的分布。在84名患者中，我们还研究了这种CTLA-4基因多态性与GAD65抗体阳性之间的关联。通过聚合酶链反应-限制性片段长度多态性方法分析外显子1第49位的A/G转换。使用放射性配体结合试验检测GAD65抗体。患者和对照者中CTLA-4等位基因的分布没有显著差异，在IDDM组中比较GAD65抗体阳性和阴性个体时，CTLA-4等位基因的患病率也没有差异。本研究不支持日本人群中CTLA-4基因与IDDM之间存在关联。
