Gene Frequencies in the Cat Population of Buenos Aires, Argentina, and the Possible Origin of This Population

The phenotypes of 295 stray cats seen in the capital area of Buenos Aires, Argentina, between March and December of 1989 were recorded. The corresponding mutant allele frequencies were as follows: O = 0.28, a =0.83, T^a= 0.01; t^b= 0.31; d = 0.45; I = 0.40; S = 0.28; W = 0.02. The allele frequencies calculated at the O locus were consistent with those expected for a randomly breeding population according to the formula for the Hardy- Weinberg equilibrium. The analysis of the genetic distances between Buenos Aires and several European cat populations revealed that the Spanish and, especially, those with a proven more ancestral genetic constitution, are the most closely related. When a similar analysis was carried out, including other Latin American cat populations, those of Spanish origin were found to show the highest degree of relatedness. These findings suggest that the Buenos Aires cat population was not genetically structured following the "two-stepping- stone" model and support the hypothesis that differential gene flows play a transcendental role in understanding the genetic composition of domestic cat populations.