Different instability of the CAG microsatellite in two haplotype groups of human mitochondrial DNA polymerase gamma

Two single nucleotide polymorphisms of the mitochondrial DNA polymerase gamma gene (POLG1), rs2238296 (T/C) and rs758130 (T/C), were analyzed in individuals of different ethnicity (Russians and Buryats) with known genotypes of the CAG microsatellite located in the same gene. It was shown that microsatellite alleles with repeat numbers other than 10 were significantly more frequent within the TT haplotype. A phylogenetic analysis of human and chimpanzee POLG1 intron 2 sequences suggested that the haplotype TT, which is more heterogeneous regarding the CAG repeat polymorphism, is evolutionally younger than the haplotype CC. These data may be useful in the further research of the association between the CAG microsatellite polymorphism of POLG1 and male infertility.     

Hypoderma actaeon: an emerging myiasis in roe deer (Capreolus capreolus)

Subcutaneous larvae of Hypoderma spp. (Diptera: Oestridae) were detected in the dorsal region in 10 roe deer, Capreolus capreolus (Artiodactyla: Cervidae), hunted in central Spain between January and March 2016. All larvae were found in the inner side of the hide during the skinning of the animals. The study of the morphological features of eight larvae of different stages collected from two animals allowed the identification of Hypoderma actaeon Brauer. The small size (4–5 mm) of some of the first instars suggests that the internal lifecycle of H. actaeon may be exclusively subcutaneous. This is the first confirmation of H. actaeon in roe deer; however, further studies to assess the spread of the parasite and to follow the evolution of this myiasis in roe deer are needed.     

The Effect of the Nucleotide Context on Induction of Mutations in Hypervariable Segment 1 of Human Mitochondrial DNA

The distribution of unstable nucleotide positions with a higher frequency of homoplastic mutations was analyzed in hypervariable segment 1 (HVS1) of the major noncoding region of human mtDNA. Three motifs (GTAC, ACCC, CCTC) proved to be associated with a higher rate of point substitutions at unstable positions. The motifs were often arranged in direct, including tandem, repeats. Motifs CCTC and ACCC were found in extended poly(C) tracts, which form direct repeats associated with deletions and tandem duplications. The results suggested that the inconstancy of the human mitochondrial genome is to a great extent determined by context-dependent mutations.     

具size结构种群竞争系统的最优控制

研究基于size结构的种群模型的控制问题,利用特征线法给出了系统的形式解,由Banach不动点定理和Gronwall不等式推导了系统及其共轭系统的适定性,并依靠法锥相关知识证明了最优控制问题解的存在必要条件.     

Mitochondrial DNA Variation in Russian Populations of Krasnodar Krai,Belgorod, and Nizhni Novgorod Oblast

Mitochondrial DNA (mtDNA) polymorphism was examined in three Russian populations from the European part of Russia (Krasnodar Krai, Belgorod, and Nizhnii Novgorod oblast). This analysis revealed that mitochondrial gene pool of Russians was represented by the mtDNA types belonging to groups H, V, pre-V, HV*, J, T, U, K, I, W, and X. The major groups (average frequency over 5%) were H, V, J, T, and U. Mongoloid admixture in Russians, constituting only 1%, was revealed in the form of mtDNA types of groups C and D. Analysis of the frequency distribution of the mtDNA type groups indicated the absence of genetic differences between the Russian populations studied.     

The macrohaplogroup U structure in Russians

The structure and diversity of mitochondrial DNA (mtDNA) macrohaplogroup U lineages in Russians from Eastern Europe are studied on the basis of analysis of variation of nucleotide sequences of complete mitochondrial genomes. In total, 132 mitochondrial genomes belonging to haplogroups U1, U2e, U3, U4, U5, U7, U8a, and K are characterized. Results of phylogeographic analysis show that the mitochondrial gene pool of Russians contains mtDNA haplotypes belonging to subhaplogroups that are characteristic only of Russians and other Eastern Slavs (13.7%), Slavs in general (11.4%), Slavs and Germans (17.4%), and Slavs, Germans, and Baltic Finns (9.8%). Results of molecular dating show that ages of mtDNA subhaplogroups to which Russian mtDNA haplotypes belong vary in a wide range, from 600 to 17000 years. However, molecular dating results for Slavic and Slavic-Germanic mtDNA subhaplogroups demonstrate that their formation mainly occurred in the Bronze and Iron Ages (1000–5000 years ago). Only some instances (for subhaplogroups U5b1a1 and U5b1e1a) are characterized by a good agreement between molecular dating results and the chronology of Slavic ethnic history based on historical and archaeological data.