Common SNP variants with MAFs >0.10 and <0.50 ranged from 30.31% in gayal to 88.57% in ND populations.
With an FST value of 0.33 and Reynolds distances of 0.31, gayal showed strong differentiation from B.
The first and the second principal components (PC1 and PC2) explained 90.24% of the total variation and evidently distinguish the two zebu populations from gayal. The results coincided well with the STRUCTURE output at K = 2 and K = 3 (Figure 2).
In this study, we estimated genetic diversity and population structure of Bangladeshi zebu cattle populations and the semi-domesticated gayal breed by using a high-density SNP genotyping chip recently developed from indicine cattle.
In this paper, we focus on the merits of the genetic potential gayal across its distribution and address the urgent need of Bangladeshi gayal population to protect them from extinction since the population is facing a formidable situation.
KARYOTYPIC AND PHYLOGENETIC STUDIES REVEAL THE ORIGIN OF GAYAL
There are two major hypotheses on the origin of the gayal: i) they were directly domesticated from wild gaur (Simoons, 1984); and ii) they were a hybrid descendant from crossing of wild gaur and domestic cattle, either B.
Several researches have been conducted to elucidate the origin of gayal. Shan et al.
The gayal (Bos frontalis), also called mithan or mithun, is found in China only in the Dulong River and Nujiang River Basin in Yunnan Province, and in Menyu and Luoyu regions of the Tibet Autonomous Region where the altitude ranges between 1,500 M-4,100 M.
The gayal was classified as a separate subgenus, together with Bali cattle (Bos banteng), the kouprey (Bos sauveli) and the gaur (Bos gaurus), and distinct from European cattle (Bos taurus) and zebu cattle (Bos indicus) (Williamson and Payne, 1977).
Molecular phylogeny and taxonomic status of the gayal
(1984) proposed that the gaur was the wild ancestor of the gayal according to karyotype, red blood cells and haemoglobin type.