A Characterization of Microsatellite Loci Variation in Panthera leo, Acinonyx jubatus and Fells concolor

Abstract

The behavior and sensitivity of microsatellite allele variation patterns to historic demographic perturbations was examined by genotyping approximately 90 microsatellite loci in samples of different populations of cheetah, Acinonyx jubatus, lion, Panthera leo, and puma, Puma concolor. Three populations (Gir Forest lions, Florida panther/puma, and cheetah species) had been shown previously to have reduced genetic diversity based on allozyme, major histocompatibility complex (MHC)- restriction fragment-length polymorphism (RFLP), mitochondrial (mt) DNA-RFLP and multilocus minisatellite DNA fingerprints, due to historic reduction in their population sizes followed by inbreeding. The observed level of microsatellite variation was substantially decreased in Florida panther and Gir lion, but appreciable in outbred lions, puma and cheetah populations. A phylogenetic analysis of composite individual microsatellite genotypes revealed considerable inter and intra-specific subdivision. Further, the pattern of allele distributions (i.e., continuous versus having "missing" allele states) was used to interpret whether residual variation after demographic reduction is a sampling transmission (i.e., retention of some ancestral allele variation) or reconstitution by new mutations. The date of the most recent cheetah bottleneck was estimated at 10,500 years ago based upon mutational reconstitution of microsatellite variation, while the Gir Forest lion bottleneck occurred 3,000-4,000 years ago based on the breadth of apparent microsatellite allele reconstitution. The value of microsatellite variation patterns as indicators of historic contraction, of population subdivision, as an evolutionary chronometer and as a metric for relative kinship were evaluated empirically. The microsatellites demonstrate that such loci provide a more precise and refined measure of these influences than characterizations by molecular genetic markers used previously to assess the status of natural populations.