Analyzing the genetic diversity of Gayal (Bos frontalis) based on whole genome resequencing

The Gayal ( Bos frontalis ) is a rare and endangeredsemi-domesticated cattle species with unique genetic background and physiological characteristics. These physiological traits are like those of yaks lived on the Qinghai-Tibet Plateau, such as thicker myocardial connective tissue and abundant vascular distribution. The unique genes carried in its genome, including candidate genes related to immunity, meat quality, and reproduction, further highlight its biological value. However, due to its small population size, severe inbreeding, and the impact of human activities, the genetic diversity of Gayal is relatively low, placing it at risk of endangerment. Therefore, protecting Gayal is not only a rescue effort for this rare species but also a significant contribution to biodiversity and genetic resources. Through scientific research and effective conservation measures, the unique genetic resources of Gayal hold promise for providing valuable references for future livestock breeding and biomedical research. Genomic studies have revealed significant differences between Gayal and other cattle species, suggesting its potential as a genetic resource for hybrid improvement, which is of great importance for the development of China's livestock industry. To evaluate the population structure and genetic diversity of Gayal, this study used a 55K genotyping array to perform whole genome resequencing on 30 Gayal samples and downloaded 69 samples from 18 cattle breeds from the NCBI database (National Center for Biotechnology Information) for joint analysis. Using population genetic structure analysis, evaluate genetic diversity parameters (heterozygosity, proportion of polymorphic markers, and nucleotide diversity), population phylogenetic tree analysis, linkage disequilibrium (LD), population structure, and genetic differentiation (FST and genetic distance). The genetic diversity results indicate that the genetic diversity of Gayal is relatively low compared to other ruminant species. The LD pattern indicates that the genetic recombination rate of Gayal is high. Principal component analysis showed that the Gayal, as an independent species, exhibited significant genetic differentiation from the Mithun. We also identified a series of candidate genes, including TRIM77, RASGRP1, API5, CLDN18, NAALAD2, DZIP1L, RAB3C, PDE4D , which may be related to the meat quality, immunity, and reproduction of this breed. This study provides valuable genomic resources and theoretical basis for the protection, development, and utilization of Gayal in the future.