Terao Chikashi, Ikari Katsunori, Nakayamada Shingo, Takahashi Yusuke, Yamada Ryo, Ohmura Koichiro, Hashimoto Motomu, Furu Moritoshi, Ito Hiromu, Fujii Takao, Yoshida Shinji, Saito Kazuyoshi, Taniguchi Atsuo, Momohara Shigeki, Yamanaka Hisashi, Mimori Tsuneyo, Matsuda Fumihiko
a Center for Genomic Medicine , Kyoto University Graduate School of Medicine , Kyoto , Japan .
b Center for the Promotion of Interdisciplinary Education and Research , Kyoto University , Kyoto , Japan .
Mod Rheumatol. 2016 Sep;26(5):685-9. doi: 10.3109/14397595.2015.1135856. Epub 2016 Feb 16.
Rheumatoid arthritis (RA) is the most common immune-related inflammatory arthritis affecting 0.5-1.0% of the population. Both genetic and environmental factors are associated with RA onset. Twin studies reported from European countries estimated heritability of RA as 53-65%. However, no twin studies have been reported from Asian countries.
We collected a total of 43 monozygotic and 43 dizygotic twins from 7550 patients with RA and obtained information of RA status in the twin pairs. We characterized RA patients whose twin siblings had RA. Variance components analysis was performed to estimate heritability in RA in the Japanese population.
Four and one patients with RA over 43 monozygotic (9.3%) and 43 dizygotic twins (2.3%), respectively, had twin siblings with RA. All the patients whose information of sero-positivity was available and whose twin siblings had RA were sero-positive. Heritability of RA was estimated as 62.2% and 56.1% in the AE and ACE models, respectively. The estimated heritability was comparable with those reported in the Europeans, compatible with previous overlap of RA susceptibility genes between Japanese and European populations.
Heritability of RA onset in the Japanese population is estimated to be comparable with that in European populations.
类风湿关节炎（RA）是最常见的免疫相关炎性关节炎，影响着0.5%-1.0%的人群。遗传因素和环境因素均与RA的发病有关。欧洲国家报道的双胞胎研究估计RA的遗传度为53%-65%。然而，亚洲国家尚未有双胞胎研究的报道。
我们从7550例RA患者中总共收集了43对同卵双胞胎和43对异卵双胞胎，并获取了双胞胎对中RA状态的信息。我们对其双胞胎兄弟姐妹患有RA的RA患者进行了特征分析。采用方差成分分析来估计日本人群中RA的遗传度。
43对同卵双胞胎中有4例RA患者（9.3%），43对异卵双胞胎中有1例RA患者（2.3%）的双胞胎兄弟姐妹患有RA。所有血清阳性信息可用且其双胞胎兄弟姐妹患有RA的患者均为血清阳性。在AE模型和ACE模型中，RA的遗传度分别估计为62.2%和56.1%。估计的遗传度与欧洲人报道的相当，这与之前日本和欧洲人群中RA易感基因的重叠情况相符。
估计日本人群中RA发病的遗传度与欧洲人群相当。
