I have suggested that the X-linked gene Tabby (Ta) and its autosomal mimics in the mouse may be homologous with the genes for sex-linked anhidrotic (hypohidrotic) ectodermal dysplasia (Christ-Siemens-Touraine syndrome, CST) and its apparent autosomal mimics in the human. In the present study, I examined whether anhidrosis, a cardinal feature of CST, is present in the putative mouse sex-linked model, Tabby. The results demonstrate that whereas normal mice perspire on the volar and plantar surfaces of their paws, hemizygous Ta/Y male mice show anhidrosis and absence of sweat glands, as do human hemizygous male sufferers of CST. This result is strongly supportive of the hypothesis that Ta is homologous to the gene for CST.