A bubaline-derived satellite DNA probe uncovers generic affinities of gaur with other bovids

DNA typing using genome derived cloned probes may be conducted for ascertaining genetic affinities of closely related species. We analysed gaur Bos gaurus, cattle Bos indicus, buffalo Bubalus bubalis, sheep Ovis aries and goat Capra hircus DNA using buffalo derived cloned probe pDS5 carrying an array of BamHI satellite fraction of 1378 base residues to uncover its genomic organization. Zoo-blot analysis showed that pDS5 does not cross hybridize with non-bovid animals and surprisingly with female gaur genomic DNA. The presence of pDS5 sequences in the gaur males suggests their possible location on the Y chromosome. Genotyping of pDS5 with BamHI enzyme detected mostly monomorphic bands in the bubaline samples and polymorphic ones in cattle and gaur giving rise to clad specific pattern. Similar typing with RsaI enzyme also revealed clad specific band pattern detecting more number of bands in buffalo and fewer in sheep, goat and gaur samples. Copy number variation was found to be prominent in cattle and gaur with RsaI typing. Our data based on matched band profiles (MBP) suggest that gaur is genetically closer to cattle than buffalo contradicting the age-old notion held by some that gaur is a wild buffalo. The pDS5 clone has a potential for estimating the generic and genetic relationship amongst closely related bovid species.