Tyr^tm1Arte

Guanosine was replaced by cytosine at nucleic acid position 308 of the tyrosinase gene, in the first exon, replicating the inactivating Tyrc mutation that results in substitution of serine for cysteine at amino acid position 103 of the tyrosinase protein; a puromycin resistance cassette flanked by frt sequences was inserted into intron 1. The selection cassette was excised by flp recombinase, leaving a single frt site in the intron. (J:213411)