1. ¹Division of Legal Medicine, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
2. ²Department of Experimental and Forensic Pathology, Faculty of Medicine, Yamagata University, Yamagata, Japan
3. ³Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
4. ⁴Department of Forensic Medicine, Fukuoka University School of Medicine, Fukuoka, Japan
5. ⁵Division of Population Genetics, National Institute of Genetics, Mishima, Japan
6. ⁶Department of Biology, Sungshin Women's University, Seoul, South Korea
7. ⁷Institute of Biological Sciences, Mongolian Academy of Sciences, Ulaan Baator, Mongolia
8. ⁸Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
9. ⁹Center of Molecular Neurogenetics, Paris, France
10. ¹⁰Amity Institute of Forensic Sciences, Defence Colony, New Delhi, India
11. ¹¹Institut für Blutgruppenforschung, Cologne, Germany

Correspondence: Isao Yuasa, Division of Legal Medicine, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan. E-mail: yuasai@grape.med.tottori-u.ac.jp

Received 11 April 2007; Accepted 24 May 2007; Published online 14 June 2007.

Abstract

Asians as well as Europeans have light skin, for which no genes to date are known to be responsible. A mutation, Ala481Thr (c.G1559A), in the oculocutaneous albinism type II (OCA2) gene has approximately 70% function of the wild type allele in melanogenesis. In this study, the distribution of the mutation was investigated in a total of 2,615 individuals in 20 populations from various areas. OCA2*481Thr prevailed almost exclusively in a northeastern part of Asia. The allele frequency was highest in Buryat (0.24) in Mongolia and showed a north-south downward geographical gradient. These findings suggest that OCA2*481Thr arose in a region of low ultraviolet radiation and thereafter spread to neighboring populations.