Sv. Kirilchik et Sy. Slobodyanyuk, EVOLUTION OF THE CYTOCHROME-B GENE FRAGMENT FROM MITOCHONDRIAL-DNA INSOME BAIKALIAN AND NON-BAIKALIAN COTTOIDEI FISHES, Molecular biology, 31(1), 1997, pp. 141-148
Partial nucleotide sequences of the cytochrome b [EC 1.6.2.2] gene loc
ated in mitochondrial DNA of 29 species of Cottoidei fishes (16 Baikal
ian and 13 non-Baikalian species) were determined. Pairwise analysis d
emonstrated that the gene evolution in Baikalian species may be charac
terized by a higher ratio of substitution mutations to synonymous subs
titutions. The causes of this difference are discussed. One of the pos
sible explanations may be an enhanced rate of accumulation of substitu
tion mutations accompanying intense speciation. Analysis of phylogenet
ic trees and of nucleotide sequences testifies to the recent origin of
the Baikalian Cottoidei complex from one or a limited number of ances
tral forms. Its evolutionary age does not exceed 2 million years.