Tyr^c-2J

This mutation has a G-to-T base change at coding nucleotide 230 resulting in an amino acid change from arginine to leucine at residue 77 (p.R77L) which lies in the highly conserved DDRE sequence. Nucleotide 230 is at the alternative 5' splice donor site for exon 1 and this allele does not produce the 1a or 1b subset of tyrosinase transcripts but does produce a significant increase in 1c and 1d transcripts. Western blots of homozygous mutant skin extracts demostrate the nearly complete absence of the broad 76-84 kDa band of glycosylated wild-type tyrosinase. No tyrosinase activity was found in hairbulb extracts from homozygous mice. (J:6611, J:36008)