Lapinski A.G., Pavlenko M.V., Solovenchuk L.L., Gorbachev V.V.
В журнале Russian Journal of Genetics: Applied Research
Год: 2016 Том: 6 Номер: 1 Страницы: 84-90
The interpretation of a signal produced by the mtDNA cytb gene as a molecular marker in phylogenetic and populationgenetic research can be complicated by the cumulative influence of parallel mutations, i.e., by the entropy of nucleotide sequences that impede differentiation among the effects of the hybridzation, natural polymorphisms, and artifacts imposed by pseudogenes. We analyzed possible limitations in the use of the mtDNA cytb gene as a molecular marker by the example of the Apodemus genus. For this purpose, the entropy of nucleotide sequences was calculated and the probable tracts of gene conversion were sought in samples of various Apodemus species from Tibet, Korea, the southern part of the Russian Primorye, and Western Europe. Many haplotypes were identified as containing tracts of gene conversion. A high level of nucleotide sequence variability was found in species from the Tibetian Plateau, particularly, in A. draco, presumably due to the influence exercised by the loweffective size of populations on the rate of point mutationaccumulation and also the role of cytochrome b in the adaptation to unfavorable environment. The effects ofhypervariability in the cytb nucleotide sequences of some samplings resulting in the entropy growth, imitatinggene conversion when compared to other species of the genus were analyzed. Furthermore, the examples ofpossible pseudogene interference among the published cytb sequences are provided. It is suggested that thestrategy in the use of the mtDNA cytb gene in population genetics and phylogenetics should be adapted to thedegree of gene variability. The emphasis is placed on the necessity of close control over sequencing data at allstages of their analysis.
