GENE ACTION AND INTERACTION IN PIGMENTATION

Beckman Center B271, Stanford University School of Medicine, Stanford, CA 94305-5323 USA

Mammalian coat color is one of the most obvious traits subject to evolutionary selection in closely related species and has provided a rich source of variation for the investigation of developmental and genetic pathways. In particular, studies of the laboratory mouse have revealed nearly 100 different loci in which mutations affect coat color in three main ways—white spotting, generalized pigment dilution, or changes in pigment-type switching. Developmental studies of individual mutations can provide clues as to the underlying molecular mechanisms, while epistasis studies can provide an outline of how signaling molecules interact with one another. Examples of how coat color genetics can be applied to study gene regulation and cell signaling will be presented in the context of work from our laboratory and others'. Comparisons will be drawn between coat color mutations in mice and those in other animals which point to a common set of genetic pathways used in most mammalian orders.