Genetic differentiation of the Volga population of the eastern imperial eagle (Aquila heliaca, Falconiformes, Accipitridae) based on the cyt b gene analysis results

Background. Despite the study of the variability of the mtDNA control region of the esternimperial eagles in the Volga population, due attention was not paid to cyt b, the second mitochondrial marker. Therefore, studies of cyt b gene polymorphism in Volga population of Aquila heliaca, taking into account the available data on mtDNA variability, are relevant and useful. This is necessary to clarify the population differentiation of imperial eagles at the level of regional breeding groups. The purpose of the research is to study the level of polymorphism of the imperial eagle (A. heliaca) on the territory of the Ulyanovsk region according to the analysis of the variability of the cyt b gene of mitochondrial DNA. In addition, it was supposed to identify specific genetic and ecological traits of the Volga population. Materials and methods. The material for genetic studies was obtained from samples (n = 15) of linn feathers of imperial eagles collected in the Ulyanovsk region. DNA was isolated according to the standard procedure of phenol-chloroform extraction after treatment of the material with proteinase K and SDS. Original primers – AqH Cyt b D (5'–GAAAGTCCCACCCTCTGCT–3') and AqH Cyt b R (5'–GCTCCAATTAGGGAAGAG–3') were used for genetic analysis of polymorphism of the cyt b gene fragment (977 bp). The polymerase chain reaction (PCR) was carried out in 25 μl of a standard reaction mixture at an annealing temperature of 60 ºC. Fragments of the mtDNA control region (n = 15) were sequenced using an ABI 3500 sequencer (Applied Biosystems). Haplotypic and nucleotide diversity were studied using the DnaSP 5.10.01 program. Maximum likelihood (ML) methods in the MEGA X program were used to reconstruct phylogenetic relationships. The Median network (Median Joining) of mitochondrial haplotypes was built in the PopART program using the TCS algorithm. The obtained nucleotide sequences of mtDNA haplotypes of the cyt b gene of the imperial eagle were deposited in GenBank NCBI – OL421575–OL421587. For statistical processing of the results, the significance level p ≤ 0.05 was set for all tests. Results. The data obtained in the course of the study on the latent polymorphism of the mitochondrial cyt b gene of geographical breeding groups of the imperial eagle on the territory of the Ulyanovsk region indicates the haplotypic diversity and specificity of the Volga population of A. heliaca. The maximum number of specific haplotypes is observed in the northeastern and southern br