Kimura Ryosuke, Watanabe Chiaki, Kawaguchi Akira, Kim Yong-Il, Park Soo-Byung, Maki Koutaro, Ishida Hajime, Yamaguchi Tetsutaro
Department of Human Biology and Anatomy, Graduate School of Medicine, University of the Ryukyus, Uehara 207, Nishihara-cho, Nakagami-gun, Okinawa 903-0215, Japan,
Department of Human Biology and Anatomy, Graduate School of Medicine, University of the Ryukyus, Uehara 207, Nishihara-cho, Nakagami-gun, Okinawa 903-0215, Japan.
Hum Mol Genet. 2015 May 1;24(9):2673-80. doi: 10.1093/hmg/ddv014. Epub 2015 Jan 22.
Hair and teeth are appendages of ectodermal origin, and there are common molecular backgrounds involved in their formation. To date, it has been revealed that a non-synonymous polymorphism in EDAR has effects on the morphological variation in both hair and teeth. Previous association studies have confirmed that single-nucleotide polymorphisms (SNPs) in/near THADA, FRAS1, WNT10A, NAF1 and FGFR2 are associated with hair morphology. In this study, we thus examined whether these SNPs are also associated with dental characteristics. We measured metric dental traits including crown size and also evaluated non-metric dental traits using plaster casts obtained from subjects (272 Japanese and 226 Koreans). DNA samples were prepared from the subjects and genotyped for the hair morphology-associated SNPs. We observed a significant association of crown size with an SNP in WNT10A (rs7349332), but not with SNPs in other genes. Therefore, we further examined four SNPs within and around WNT10A, among which rs10177996 had the strongest association with dental traits. World distribution of the derived allele in rs10177996, which is associated with larger teeth, showed that Eurasians have a higher allele frequency than Africans. Together with previous studies on hair morphology, this study demonstrated that common variations in WNT10A have pleiotropic effects on the morphology of ectodermal appendages.
毛发和牙齿是外胚层起源的附属器官，它们的形成涉及共同的分子背景。迄今为止，已发现EDAR中的一个非同义多态性对毛发和牙齿的形态变异均有影响。先前的关联研究证实，THADA、FRAS1、WNT10A、NAF1和FGFR2内部或附近的单核苷酸多态性（SNP）与毛发形态有关。因此，在本研究中，我们检测了这些SNP是否也与牙齿特征相关。我们测量了包括牙冠大小在内的牙齿计量特征，并使用从受试者（272名日本人及226名韩国人）获取的石膏模型评估了牙齿非计量特征。从受试者中制备DNA样本，并对与毛发形态相关的SNP进行基因分型。我们观察到牙冠大小与WNT10A中的一个SNP（rs7349332）存在显著关联，但与其他基因中的SNP无关联。因此，我们进一步检测了WNT10A内部及周围的四个SNP，其中rs10177996与牙齿特征的关联最强。与较大牙齿相关的rs10177996衍生等位基因的全球分布表明欧亚人的等位基因频率高于非洲人。结合先前关于毛发形态的研究，本研究表明WNT10A中的常见变异对外胚层附属器官的形态具有多效性作用。
