RRC ID 32747
Author Koga A, Hori H.
Title Albinism due to transposable element insertion in fish.
Journal Pigment Cell Res
Abstract The i locus of the medaka fish, Oryzias latipes, is responsible for tyrosinase expression, and several mutant alleles have been identified. The genotype i1/i1 exhibits a complete albino phenotype, having pale orange-red skin and red eyes. This mutant lacks in vivo tyrosinase activity. The genotype i4/i4, on the other hand, shows a quasi-albino phenotype with skin as bright as that of i1/i1 but with red-wine-colored eyes. At the light microscope level, reduced pigmentation is observed both in the skin and eyes of this mutant. The tyrosinase genes for the i1 and the i4 alleles were cloned and sequenced, and compared with that of the wild-type tyrosinase gene. The i1 allele was found to contain a 1.9-kb transposable element in the 1st exon, and the i4 allele was found to contain a 4.7-kb transposable element in the 5th exon. Both i1 and i4 are alleles that were found in a commercial breeding population. The insertion of a transposable element thus appears to constitute a natural cause of mutations that cause albinism in this organism.
Volume 10(6)
Pages 377-81
Published 1997-12-1
DOI 10.1111/j.1600-0749.1997.tb00695.x
PMID 9428004
MeSH Albinism / enzymology Albinism / genetics* Albinism / veterinary* Animals DNA Transposable Elements* Fish Diseases / enzymology Fish Diseases / genetics* Monophenol Monooxygenase / biosynthesis Monophenol Monooxygenase / genetics Oryzias / genetics*
Times Cited 18
Medaka i-6 (MT72) i (i-1) (MT67)