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1.
Genetika ; 50(10): 1200-15, 2014 Oct.
Article in Russian | MEDLINE | ID: mdl-25720252

ABSTRACT

Based on polymorphism of the 12S rRNA gene and RAPD markers, differentiation of 122 tortoise individuals belonging to the three species of genus Testudo (T. kleinmanni, T. marginata, and T. graeca), six subspecies of T. graeca (T. g. nikolskii, T. g. pallasi, T. g. armeniaca, T. g. zarudnyi, T. g. terrestris, T. g. ibera), and two subspecies of the Central Asian tortoise Agrionenemys horsfieldii (A. h. horsfieldii, A. h. kazakhstanica) was performed. For comparison, 32 known sequences of 12S rRNA gene (392 bp) from tortoises of the two genera inhabiting the territories of Europe, Asia, and Africa were used. In the populations of A. horsfieldii, a total of six haplotypes; including three newly described variants, were identified. In the examined tortoises of the genus Testudo, eleven 12S rRNA haplotypes were identified. One new haplotype was detected in T. kleinmanni. Among the eight subspecies of T. graeca, eight haplotypes were identified, with four newly described ones. The reported RAPD markers generally supported the reconstructions obtained with the use of the mitochondrial marker. Similarly to the 12S rRNA-based reconstructions, two independent clusters included representatives of the two genera, Agrionemys and Testudio. Among the latter, representatives of T. marginata and T. kleinmanni, as well as T. graeca, with high statistical support values, formed two reciprocally monophyletic groups. Compared to the mitochondrial markers, RAPDs more statisticallysignificantly discriminated the sample of T. g. terrestris and the four subspecies, T. g. ibera, T. g. armeniaca, T. g. pallasi, and T. g. nikolskii. In almost all cases except the representatives of T. g. ibera, the representatives of each of four subspecies formed individual subclusters. The geographical haplotype distribution patterns and possible evolutionary scenario of the origin and dispersal of tortoises of the two genera are discussed.


Subject(s)
DNA, Mitochondrial/genetics , Genetic Speciation , Polymorphism, Genetic , Turtles/genetics , Animals , Evolution, Molecular , Genetic Markers , Haplotypes , Phylogeny , Phylogeography , RNA, Ribosomal/genetics , Turtles/classification
2.
J Evol Biol ; 21(2): 527-40, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18179513

ABSTRACT

In recent years many cases of hybridization and introgression became known for chelonians, requiring a better understanding of their speciation mechanisms. Phylogeographic investigations offer basic data for this challenge. We use the sister species Mauremys caspica and M. rivulata, the most abundant terrapins in the Near and Middle East and South-east Europe, as model. Their phylogeographies provide evidence that speciation of chelonians fits the allopatric speciation model, with both species being in the parapatric phase of speciation, and that intrinsic isolation mechanisms are developed during speciation. Hybridization between M. caspica and M. rivulata is very rare, suggesting that the increasing numbers of hybrids in other species are caused by human impact on environment (breakdown of ecological isolation). Genetic differentiation within M. caspica and M. rivulata resembles the paradigm of southern genetic richness and northern purity of European biota. However, in west Asia this pattern is likely to reflect dispersal and vicariance events older than the Holocene. For M. caspica three distinct Pleistocene refuges are postulated (Central Anatolia, south coast of Caspian Sea, Gulf of Persia). Morphologically defined subspecies within M. caspica are not supported by genetic data. This is one of the few studies available about the phylogeography of west and central Asian species.


Subject(s)
Biological Evolution , DNA, Mitochondrial , Gene Flow , Genetic Variation , Hybridization, Genetic , Turtles/genetics , Animals , DNA Fingerprinting , Geography , Mediterranean Region , Middle East , Minisatellite Repeats , Turtles/anatomy & histology
3.
Tsitologiia ; 48(4): 332-45, 2006.
Article in Russian | MEDLINE | ID: mdl-16841495

ABSTRACT

We studied variation of microsatellites BM224 and Bcal7 in three species of the Bufo viridis diploid-polyploid complex. We found that locus Bcal7 in all examined samples was monomorphic. Three alleles of microsatellite BM224 were found. Among tetraploid toads, the western species B. oblongus had only one allele variant, whereas the eastern species B. pewzowi had two other alleles. Similar distribution of alleles was observed in triploid specimens, collected in the area borders of tetraploid and diploid species. Among samples of diploid toad B. viridis, we found all three allele variants of microsatellite BM224. Their distribution was geographically determined. A comparison of allele distribution with genome size variation in diploid toads showed very similar patterns.


Subject(s)
Bufonidae/genetics , Cell Nucleus/genetics , Microsatellite Repeats/genetics , Ploidies , Africa, Northern , Alleles , Animals , Asia , Europe , Genetic Variation , Species Specificity
4.
Genetika ; 40(12): 1628-36, 2004 Dec.
Article in Russian | MEDLINE | ID: mdl-15648145

ABSTRACT

The polymerase chain reaction with arbitrary primers (RAPD-PCR) was used to study intraspecific variation in Mediterranean turtle Testudo graeca, which is represented by the Dagestan (T. g. pallasi) and Nikolskii (T. g. nikolskii) subspecies in Russia. To study the phylogenetic relationships, the RAPD variation was also compared in two other T. graeca subspecies (T. g. ibera and T. g. terrestris), two closely related Testudo species (T. kleinmanni and T. marginata), and Central Asian turtle Agrionemys horsfieldii. Parameters of RAPD variation showed that the sample from different geographical regions of Dagestan was more polymorphic and heterogeneous than that from Central Asia. The two samples differed in the mean number of RAPD fragments N (48.761 vs. 40.400), number of polymorphic fragments P (78.7 vs. 32.3), and within-group similarity index APS (0.607 vs. 0.784). In T. g. pallasi, no significant difference in N, P, or APS was observed between samples from different localities of Dagestan or between groups of turtles with four- or five-clawed forelegs. A dendrogram of genetic similarity between the species and subspecies under study contained two clusters, one comprising all A. horsfieldii individuals and the other, all turtles of the genus Testudo. In the latter, T. marginata and T. kleinmanni showed higher similarity to each other than to T. graeca. The four T. graeca subspecies clustered separately from each other with a high reliability, T. g. nikolskii and T. g. ibera (Turkey) being more similar to each other than to T. g. terrestris or T. g. pallasi. The possible causes of the presence of four claws on a foreleg and the relationships among members of the genus Testudo were discussed.


Subject(s)
Genetic Variation , Phylogeny , Random Amplified Polymorphic DNA Technique , Turtles/genetics , Animals , Genetics, Population
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