Copyright © 2004 The American Society of Human Genetics. All rights reserved.
The American Journal of Human Genetics, Volume 74, Issue 3, 466-471, 1 March 2004
doi:10.1086/382195
Oculocutaneous Albinism Type 4 Is One of the Most Common Types of Albinism in Japan
Katsuhiko Inagaki1, *, Tamio Suzuki1, *, 
, 
, Hiroshi Shimizu2, Norihisa Ishii3, Yoshinori Umezawa4, Joji Tada5, Noriaki Kikuchi6, Minoru Takata7, Kenji Takamori8, Mari Kishibe9, Michi Tanaka10, Yoshinori Miyamura1, Shiro Ito1 and Yasushi Tomita1
1 Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan
2 Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
3 Department of Bioregulation, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo
4 Department of Dermatology, Tokai University School of Medicine, Isehara, Japan
5 Department of Dermatology, Okayama Municipal Hospital, Okayama, Japan
6 Department of Plastic Surgery, Nihonkai Hospital, Sakata, Japan
7 Department of Dermatology, Toyama Prefectural Central Hospital, Toyama, Japan
8 Department of Dermatology, Juntendo University Urayasu Hospital, Urayasu, Japan
9 Department of Dermatology, Asahikawa Medical College, Asahikawa, Japan
10 Department of Dermatology, Mito National Hospital, Mito, Japan
Address for correspondence and reprints: Dr. Tamio Suzuki, Nagoya University Graduate School of Medicine, Department of Dermatology, 65 Tsurumai, Showa-ku, Nagoya, Japan* These authors contributed equally to this work.
Abstract
Oculocutaneous albinism (OCA) is a complex genetic disease with great clinical heterogeneity. Four different types of OCA have been reported to date (OCA1, OCA2, OCA3, and OCA4). MATP was recently reported in a single Turkish OCA patient as the fourth pathological gene, but no other patients with OCA4 have been reported. Here, we report the mutational profile of OCA4, determined by genetic analysis of the MATP gene in a large Japanese population with OCA. Of 75 unrelated patients that were screened, 18 individuals (24%) were identified as having OCA4; they harbored seven novel mutations, including four missense mutations (P58S, D157N, G188V, and V507L) and three frameshift mutations (S90CGGCCA→GC, V144insAAGT, and V469delG), showing that MATP is the most frequent locus for tyrosinase-positive OCA in Japanese patients. We discuss the functional melanogenic activity of each mutant allele, judging from the relationship between the phenotypes and genotypes of the patients. This is the first report on a large group of patients with OCA4.
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