TITLE:
Tyrosinase (Tyr) Gene Mutation in Albino Mongolian Gerbil (Meriones unguiculatus)
AUTHORS:
Takao Ukaji, Masahiro A. Iwasa, Osamu Kai
KEYWORDS:
Tyrosinase (Tyr) Gene, Mongolian Gerbil (Meriones unguiculatus), Albino
JOURNAL NAME:
Open Journal of Animal Sciences,
Vol.6 No.4,
September
30,
2016
ABSTRACT:
Tyrosinase is encoded by the Tyr (c or albino) locus and is the key enzyme in pigment biosynthesis. Loss of function of this enzyme caused by gene mutation results in albinism. Most cases of albinism are caused by missense mutations of tyrosinase. Albino mutations in Tyr have been identified in various animals, including human, mouse, rat, rabbit, cattle, cat, and ferret, but not in gerbil. We created two new gerbil strains: MON/Num/a (inbred agouti phenotype) and MON/Num/c (albino phenotype). Here, we report that four nucleotide substitutions in the Tyr gene caused two missense mutations in amino acids in the albino gerbil: a G-to-A mutation at position 204 in exon 1 caused R77H, and A-to-G at position 1392 and G-to-T at position 1393 in exon 5 caused Q473R. The substitution at position 1408 in exon 5 was silent. These missense mutations are conserved in all albino phenotypes we tested. Therefore, we suggest that these mutations are responsible for albinism in gerbil.