Molecular genetic characteristics of the allelic variants of microsatellite loci Du281, Du215, and Du323 in parthenogenetic lizards Darevskia rostombekovi (Fam. Lacertidae)

Assessment of genetic diversity of unisexual (parthenogenetic) species of vertebrates is among the major objectives of research in these species. Various nuclear or mitochondrial genome markers can be used for such an assessment. Microsatellite DNAs are among the most efficient genetic markers, since the mutation rate in these fragments is high. Identification and characterization of such markers are the basic stages of genetic research in parthenogenetic species. Allelic polymorphism of three microsatellite loci in populations of the parthenogenetic species Darevskia rostombekovi (n = 42) and bisexual parent species D. raddei (n = 6) and D. portschinskii (n = 6) has been assessed by locus-specific PCR for the first time. All representatives of the parthenogenetic species D. rostombekovi used in the present study turned out to be heterozygous. The number of alleles of the different loci ranged from two to five in the populations investigated. The nucleotide sequence of the allelic variants of the loci investigated has been determined. The differences between the alleles were apparently related to variation in the structure of microsatellite clusters and single-nucleotide substitutions in DNA fragments located in the vicinity of the clusters at fixed distances from the latter. Structural variants of the alleles formed allele-specific haplotype markers that were inherited from the bisexual parent species. The origin (inheritance from the maternal or paternal species) has been determined for each allele of the parthenogenetic species. The distribution, frequency of occurrence, and pattern of combination of the alleles of microsatellite loci in D. rostombekovi populations have been characterized; these features determined the identity of each population. The data obtained can be used for assessment of the clonal diversity of the parthenogenetic species D. rostombekovi and the identification of a possible scenario of the emergence of the diversity in the populations.