Comparative chromosome mapping of repetitive DNA in four minnow fishes (Cyprinidae, Cypriniformes)

Abstract

The present study focused on the repetitive DNA of the chromosome in four minnow fishes from the genera Danio Hamilton, 1822, Devario Heckel, 1843 and Rasbora Bleeker, 1859. Chromosomes were analysed using fluorescence in situ hybridization (FISH) with microsatellite probes including (CA)15, (CAC)10, (CGG)10, (GC)15 and (TA)15 staining. All species retained the diploid chromosome number 2n = 50 in male and female. The microsatellite sequences were mapped in the chromosomes of Danio albolineatus (Blyth, 1860), Devario regina (Fowler, 1934), Rasbora aurotaenia Tirant, 1885 and R. paviana Tirant, 1885. In most cases, the microsatellite was dispersed in the chromosome with conspicuous markings in the telomeric region and the whole genome, which suggests that sequences contribute to chromosome structure and may have played a role in the relationship of this fish group. The comparative genome mapping data presented here provide novel information on the structure and organisation of the repetitive DNA region of the minnow’s genome and contribute to a better understanding of the genomes of these minnows.