Using Microsatellite Dna To Analyze Population Structure In Clemmys Guttata

Using Microsatellite DNA to Analyze Population Structure in Clemmys Guttata

The spotted turtle (Clemmys guttata) is a small, semiaquatic species that has been listed as a species of special concern in Massachusetts. Populations of the species on Nantucket Island exist in fragmented and possibly isolated populations, although the effect of this fragmentation on current population structure is unknown. This study attempted to look at the population structure of two populations, one from the Medouie Creek Wetland Complex on Nantucket Island and a mainland population from Halifax, MA. Microsatellite loci were examined to analyze the population genetics and compare two populations. Seven microsatellite loci were analyzed in 40 spotted turtles sampled from Nantucket Island and 10 turtles from Halifax. The seven microsatellite loci were found to be highly polymorphic. A total number of 92 alleles were found across all loci, with the number of alleles per locus ranging from seven to sixteen. Using various statistical tests, the multilocus genotypes of individuals in both populations were analyzed to determine population structure. Both populations were found to be i Hardy-Weinberg and linkage equilibrium and highly significant genetic variation was found within and between the Nantucket and Halifax populations. Private alleles were found in both populations across all microsatellite loci and analysis of these alleles indicates some loss of genetic diversity in the Nantucket Island population. Overall, the results of this study were used to classify the Nantucket Island and Halifax, MA populations as genetically distinct from each other and that all individuals sampled belong to two genetic clusters that correlate to geographic population assignment. These data suggest that the two populations should be regarded as distinct management units.

The Zoological Record

Canadian Journal of Zoology