Colorful discovery: first medaka gene positionally cloned
The process of pigmenting the skin is of great importance for health - to which the soaring rate of melanoma in whites and the increased sensitivity to solar radiation by albinos testify.
The factors that are known to control the synthesis of melanin are almost completely conserved throughout the animal kingdom. This bodes well for geneticists who use non-human species as models for understanding melanin production. The Japanese medaka -- a fish species bred by enthusiasts for centuries and revered for the variety and beauty of its strains -- now makes a debut in Nature Genetics (Vol. 28, pp. 355-360), with the discovery of a gene controlling melanin production by Shoji Fukamachi (of the University of Tokyo) and colleagues.
The b medaka mutant has an orange-red color and almost no melanin in its body. By studying this strain, Fukamachi et al. have uncovered the genetic basis of its lack of melanin: a mutated gene (called AIM1) that has some similarities to genes that are known to encode sucrose transporters. They have also discovered that humans and mice have their own versions of AIM1, and so the finding in medaka seems likely to lead to a better understanding of pigment production in terrestrial vertebrates too.
As Alan Packer (Assistant Editor of Nature Genetics) explains an accompanying News & Views article, the medaka is the focus of increasing attention from geneticists, and the current paper is a landmark in that it describes the first successful positional cloning of a medaka gene.
Dr. Shoji Fukamachi
Department of Integrated Biosciences
Graduate School of Frontier Sciences
University of Tokyo
Telephone: +81 3 5841 4443
Fax: + 81 3 5841 8096
Dr. Alan Packer
New York, New York, USA
Telephone: +1 212 726 9277
Fax: +1 212 545 8341
(C) Nature Genetics press release.
Message posted by: Trevor M. D'Souza