Analysis of tandem DNA repeats of cottoid fish in Lake Baikal by direct consensus sequencing

This paper presents a simple method of consensus sequencing of monomeric repeat units during a single sequencing procedure by the example of a recently found BspMII family of tandemly arrayed repeats of Baikal cottoid fish (Cottoidei). This approach is based on obtaining multimeric repeat forms by the polymerase chain reaction, which eliminates the need of cloning and significantly simplifies the use of tandem repeats in phylogenetic studies. An attempt has been made to derive a phylogenetic evolution pattern of the In1 element of BspMII repeats for eight cottoid species of Lake Baikal. The position of two golomyanka species (Comephorus dybowskii and Comephorus baicalensis) on a phylogenetic tree confirms the theory of their relatively recent origin, based on mitochondrial cytochrome b gene analysis. It was estimated that the tandem repeat element In1 evolves at least one order of magnitude faster than genome coding sequences.