Chromosomal evolution of the Canidae. II. Divergence from the primitive carnivore karyotype.

The Giemsa-banding patterns of chromosomes from the arctic fox (Alopex lagopus), the red fox (Vulpes vulpes), the kit fox (Vulpes macrotis), and the raccoon dog (Nyctereutes procyonoides) are compared. Despite their traditional placement in different genera, the arctic fox and the kit fox have an identical chromosome morphology and G-banding pattern. The red fox has extensive chromosome arm homoeology with these two species, but has only two entire chromosomes in common. All three species share some chromosomes with the raccoon dog, as does the high diploid-numbered grey wolf (Canis lupus, 2n = 78). Moreover, some chromosomes of the raccoon dog show partial or complete homoeology with metacentric feline chromosomes which suggests that these are primitive canid chromosomes. We present the history of chromosomal rearrangements within the Canidae family based on the assumption that a metacentric-dominated karyotype is primitive for the group.