GENETIC-STRUCTURE OF THE MARSEILLES CAT POPULATION - IS THERE REALLY A STRONG FOUNDER EFFECT

In a previous study on the Marseilles cat population it was concluded that the small cat colonies were subject to a strong founder effect. A more detailed study with the G(ST) and F(ST) (genetic diversity) stat istics and with a spatial autocorrelation analysis shows that, for the a (non-agouti) and t(b) (blotched) genes, there is neither significan t heterogeneity nor spatial autocorrelation. This is probably due to a n appreciable gene flow throughout Marseilles (although a uniform sele ction pressure in favour of these alleles cannot be totally ruled out) . The O (orange) allele does not show spatial autocorrelation either, but it does show significant heterogeneity, which could have been caus ed by the late introduction of this allele into the population, coming from populations with low O frequencies in a sporadic and irregular w ay (although the influence of diversifying selection cannot be complet ely ruled out). Only this allele O might be influenced by a strong fou nder effect as stated previously. However, the a and t(b) data do not support the hypothesis of a strong founder effect in these cat colonie s.