Synthetic DNA-based genetic markers reveal intra- and inter-species DNA sequence variability in the Bubalus bubalis and related genomes

Abstract

A series of synthetic oligonucleotide probes were developed as markers for genetic analysis and molecular systematics of Bubalus bubalis and other eutherian mammals. A very high level of heterozygosity (~95%) was observed in the bubaline genome, with an overall band-sharing probability of 2.08 × 10^-11 using (TGG)₆ and Hinf I probe-enzyme combination. Breed affiliation studies on different buffalo breeds, viz. Toda, Surti, Mehsana, and Murrah, revealed that the semiwild Toda breed belonged to a distinct group. The desired genotypes in each successive generation in an actual breeding program were also identified by employing a DNA fingerprinting approach using these markers. Estimation of genetic distances by calculating the mean allelic frequencies at (CA)_n, (TGG)_n, and (GGAT)_n repeat loci between buffalo and other related animals such as horse (order Perisodactyla), rabbits (order Lagomorpha, (pigs, cattle, goat, and sheep (order Artiodactyla) revealed that with respect to the genetic distance coefficient (GDC), goat (caprine) was closer to buffalo (GDC = 0.0005) than sheep (ovine) (GDC = 0.0007). The genetic distance between horse and buffalo was calculated to be 0.4085, indicating that compared to other animals, horse was distantly related to buffalo. The understanding of overall allelic variations and breed affiliation of the bubaline genome will contribute to the propagation and conservation of the desired germ plasm and better management of this species.