Genetic Differentiation of the Arctic Phylogenetic Group of Charr from Northeast Asia and North America

A comparative analysis of the mitochondrial DNA variability in Salvelinus taranetzi (and closely related taxa) from Asia and Salvelinus alpinus erythrinus from the Northwest Territories (NWT), North America, representing the Arctic phylogenetic group of charrs of the genus Salvelinus, has been carried out. The estimated divergence of the combined nucleotide sequences of the mtDNA CoI and Cytb genes and CR region within the discussed phylogroup varies in the range of 0.001-0.003 and does not exceed the intraspecific variability of S. taranetzi. A genealogical analysis confirms the phylogenetic proximity of S. a. erythrinus from NWT and S. taranetzi from Asia. By assuming a common origin of S. taranetzi and S. a. erythrinus, we have shown a significant differentiation between the geographical populations as a result of probable fragmentation of their common ancestor's range. According to the hierarchical analysis of molecular variance (AMOVA), the intergroup component accounts for the major part (83% of variance) of the mtDNA variability (490 bp, CR) with a low genetic diversity within the groups (10%). The region of Anadyr-Kolyma Basin, which determines the heterogeneity of the phylogroups, stands out on a broad geographical scale.