Geographic Distribution of Mutant Alleles in Domestic Cat Populations of New England and the Canadian Maritimes

Domestic cats are polymorphic for six loci which determine coat colour, a locus determining hair length and one controlling the expression of the skeletal anomaly polydactyly. A total of more than 5000 cats in thirty-five populations in Eastern Canada and the Northeastern United States were surveyed and gene frequencies were determined. In the study area significant heterogeneity was found between populations for all the loci studied. A small part of this heterogeneity (16%) appears to be due to geographic distance between populations. A significant association was found between four temperature related variables and the frequency of the longhair and dominant white alleles. This suggests that natural selection has had a significant effect on gene frequency in the 200-300 generations since domestic cats were introduced to America. Some part of the residual variation is probably due to differential origin of some of the populations.