Androgenetic alopecia: in vivo models.

Androgenetic alopecia is the most common form of balding in humans. There is great interest in finding a reliable animal model to study the pathogenesis and treatment of this abnormality. The sump-tailed macaque (Macaca artoides) has been the standard model and appears to be useful homologue. These primates are reasonably good predictors of compound efficacy. Due to reduced size and expense, rodent models have been sought. Testosterone inducible models require more development but offer potential. Xenografts of human skin to immunodeficient mice, notably nude or severe combined immunodeficiency, are small, relatively inexpensive, and easy to work with if a source of human tissue is available. Xenografts to double mutant mice for severe combined immunodeficiency and a number of hormone receptor null mutations offer new refinements to these xenograft models.