ABSTRACT
The frizzy (fr) mutation occurred spontaneously in 1949 in a pink-eye chinchilla shaker-1 stock at the Jackson Laboratory. The frizzy locus maps to mouse Chromosome 7 and is a recessive mutation. Frizzy mice (fr/fr) can be identified within 1 or 2 days of birth by the presence of wavy or curly vibrissae, which persists throughout life. Little has been reported on the microscopic lesions of fr/fr mice. By scanning electron microscopy, the hair shafts of the frizzy mutation showed multiple defects in the cuticle scales, as well as in the integrity of the hair shaft itself. The scale edges were often found to be lifted from the surface of the hair shaft. Long-axis splits of the hair shaft could be found on both awl and guard hairs. This particular defect was not found on the other hair types. DNA extracts are available from the Mouse DNA Resource at the Jackson Laboratory.
