065 Unique Form of Murine Alopecia: A Mouse Model for Human Hair Disorders.

Liren Tang1, Liping Cao1, Michele Surbey2, Jackie Jacob3, Harvey Lui1 and Jerry Shapiro1 1Division of Dermatology, University of British Columbia, Vancouver, Canada; 2School of Psychology, James Cook University, Townsville, Australia; 3Department of Psychology, Mount Allison University, Canada

The rodent has been a useful model and biomedical tool for studying human hair disorders. An undocumented form of alopecia in CD-1 mice has been maintained over several years by selective breeding. Spontaneous alopecia occurs in 25-30 % of the selected population and affects females 3 times more often than males. The process of hair loss normally begins after sexual maturity in both sexes. In affected mice, normal hair growth occurs until approximately 40 days of age and is subsequently followed by rapid hair loss (few days) from a rectangular area between the ears. This localized alopecia lasts for months and the hairs appear to grow back in a majority of mice following a variable period of time. Over the generations, some mice became thinned rather than bald in the rectangular area. Histopathology from the established bald patches reveals an absence of matured hair follicles and exhibits no peri- or intra-follicular lymphocyte infiltration. Initial pedigree analysis suggests the involvement of two or more recessive alleles, with further genetic analysis necessary to elucidate the mode of transmission. This localized and rectangular pattern of murine alopecia may be a potentially useful model for one of the major types of human alopecias.