Uncv (uncovered): a new mutation causing hairloss on mouse chromosome 11

A pair of mutant mice with a first sparse coat appeared spontaneously in th e production stock of BALB/c mice with a normal coat. After being sib-mated , they produced three phenotypes in their progeny: mice with normal hair, m ice with a first sparse coat and then a fuzzy coat, and uncovered mice. Gen etic studies revealed the mutants had inherited an autosomal monogene that was semi-dominant. By using 11 biochemical loci - Idh, Car2, Mup1, Pgm1, Hb b, Es1, Es10, Gdc, Ce2, Mod1 and Es3 - as genetic markers, two-point linkag e tests were made. The results showed the gene was assigned to chromosome 1 1. The result of a three-point test with Es3 and D11Mit8 (microsatellite DN A) as markers showed that the mutation was linked to Es3 with the recombina tion fraction 7.89+/-2.19%, and linked to D11Mit8 with the recombination fr action 26.30+/-3.57%. The recombination fraction between Es3 and D11Mit8 wa s 32.90+/-3.81%. It is suggested that the mutation is a new genetic locus t hat affected the skin and hair structure of the mouse. The mutation was nam ed uncovered, with the symbol Uncv. Further studies showed the mutation aff ected not only the histology of skin and hair but also the growth and repro ductive performance of the mice. The molecular characterization of the Uncv locus needs to be further studied.