Gray mutant in the Mongolian gerbil.

A new autosomal recessive mutant, gray (symbol g), is reported for the Mongolian gerbil. The pelage of mutant animals is devoid of phaeomelanin pigment while the eumelanin is scarcely affected. The normal sandy-gray agouti wild type becomes a light gray. The phenotypes that result from combining the gray gene with previously reported color genes, nonagouti, (a,) and pink-eyed dilution (p), are described.