Abstract

The present invention started when a .lambda.gt11 cDNA library of normal human melanocytes was screened with antibodies directed against purified hamster tyrosinase. Two important cDNA clones were isolated: cDNA .lambda.mel 34 and .lambda.mel 17-1. It is concluded that .lambda.mel 34 contained cDNA encoding human tyrosinase. Moreover, the cDNA gene for human tyrosinase was recovered from the .lambda.mel 34 and can be used for many purposes including the production of pure human tyrosinase. This gene and its promoter are characterized herein. Studies suggested that .lambda.mel 17-1 gene product act on melanin biosynthesis's pathway distal to tyrosinase. Melanocytes preferentially express an mRNA species, Pmel 17, whose protein product cross reacted with anti-tyrosinase antibodies and whose expression correlated with the melanin content. The deduced protein structure has been analyzed and its chromosomal location in mouse and man has been mapped. The human Pmel 17 gene, designated D12S53E, maps to Chromosome 12, region 12pter-q21; and the mouse homologue, designated D12S53Eh, maps to the distal region of mouse Chromosome 10, a region also known to carry the coat color locus si (silver).