Tyr^c-Brd

This mutation arose spontaneously in or around 1991 in the C57BL/6 colony of Dr. Alan Bradley. It has been used in linkage studies based on the location of the tyrosinase gene on Chr 7, and its phenotype is complemented by a tyrosinase mini-gene. Sequence analysis of exon 1 identified the same G-to-T transversion at coding nucleotide 230 (c.230G>T), resulting in replacement of arginine by leucine at amino acid position 77 (p.R77L), that is present in the albino 2 Jackson allele Tyrc-2J. It reverts at a very low frequency (there were two incidences in the original colony between 1992 and 1995), resulting in black pups in otherwise albino litters. (J:115975, J:115976)