Juvenile bare: a new hair loss mutation on chromosome 7 of the mouse

We describe a new juvenile hair loss mutant in the mouse in which the hair follicle follows irregular pathways to the surface and generally becomes dystrophic when the mouse is about 23 days of age. Skin from mutant mice older than 1 month of age is histologically normal, although adult mutant mice show a slightly more sparse coat than normal. Grafts of mutant littermates skin to SCID hosts indicate that the condition is probably a systemic response rather than one of the follicle per se. The hair loss is caused by a recessive mutation, which we have named juvenile bare (jb), located on proximal chromosome 7.