Abstract
The genetics of coat variation is a powerful system for studying the fundamental aspects of gene action and the evolutionary mechanisms that give rise to morphological diversity. The domestic dog is an ideal platform for this approach due to the variety of coat colours, textures and patterns represented among modern breeds, and a unique population history that facilitates efficient and precise gene localization. Topics discussed are evolutionary history of the domestic dog and application to gene mapping; pigment cell development and survival; generalized pigment dilution; pigment-type switching; genetics of hair structure in the domestic dog; and hair follicle development and biology.