Analysis of genetic polymorphism and the identification of the mi-RNA binding sites of the hypoxia related genes in Indian breeds of cattle

There are certain cattle breeds which are adaptable to the temperate type environmental conditions of high altitude regions of Himalayas. The genome of such cattle have signature of adaptability in the genes related to the hypoxia. Therefore, the current study was undertaken on three hypoxia related genes (EGLN2, EGLN3 and EPAS1) in four breeds of cattle adapted to the diverse agro-climatic conditions of high (Ladakhi and Siri) and low (Hallikar and Kankrej) altitude.

The genotyping of the samples was carried out by using 777 K BovineHD Bead Chip (Illumina) at Agri genome Pvt. Ltd (Kerala) and the in-silico analysis of the samples was carried out at ICAR-NBAGR during 2019–2020. The SNPs underlying the genes were evaluated for the gene and genotypic frequencies at nine SNP loci residing in these three candidate genes (EGLN2, EGLN3 and EPAS1). The diversity parameters for these SNPs were assessed by GenAl Ex 6.2 software and Minor Allele Frequency (MAF) differences among the breeds were calculated by Duncan's Multiple Range Test (DMRT) using SAS software. The mi-RNA binding sites in the 3’UTR region of genes were identified by Target Scan software.

Higher level of polymorphism was obtained in the Ladakhi and Siri breeds of cattle of high altitude/cold adapted region than Hallikar and Kankrej of plain and hot arid/semi-arid region. Several mi-RNA binding sites were obtained in the 3’UTR region of these 3 genes by Target Scan software. The polymorphism obtained in these candidate genes can be utilized in the markers assisted selection of the animals more adapted to the extreme cold and high altitude region for their genetic improvement as well as designing tools for the therapy of the diseases prevalent at high altitude.