Age-related pigmentation changes in the coats of allophenic mice.

Hair pigmentation and patterns of pigmentation change with age in the coats of BALB/cByJ in equilibrium C57BL/6J allophenic mice. These changes are particularly evident on the dorsum where there is an increase in the proportion of white areas at the expense of agouti and black areas. The most plausible explanation for these changes is that they represent a continuous selection for one of the two genotypes of cells from which the melanoblasts and hair follicles of these animals are derived.