Climate change in India is likely to aggravate the heat stress in dairy animals due to rise in temperature coupled with increased precipitation. In animals heat stress affects the alteration of plasma Potassium (K (+)) and Sodium Na (+) ions. ATP1A1 gene belongs to the family of P-type cation transport ATPases, and to the subfamily of Na+/K+ -ATPases. Na+/K+ -ATPase is an integral membrane protein responsible for establishing and maintaining the electrochemical gradients of Na+ and K+ ions across the plasma membrane. The present study is aimed to investigate the polymorphisms in the entire coding region of ATP1A1 gene in Bos indicus (Deoni) cattle by PCR- Single-Strand Conformation Polymorphism (PCR- SSCP) and direct sequencing of variants. Sequence analysis showed 16 SNPs, of which 5 SNPs were in the coding region and the remaining 11 SNPs were detected in the non-coding region of ATP1A1 gene. All the observed variations in the coding regions of ATP1A1 gene were silent mutations. The genotypic, allelic frequencies, c&sup2; test for Hardy-Weinberg equilibrium and Shannon&rsquo;s information index were calculated using POPGENE-32. The study revealed a high degree of genetic variability in ATP1A1 gene in the Deoni cattle population which indicated the utility of this gene for further studies for identification of markers associated with heat tolerance in Indian humped cattle for using in marker assisted selection for heat tolerance.&nbsp;

Genetic characterization and identification of single nucleotide polymorphisms of ATP1A1 gene in Indian humped cattle

Expression of stress genes under thermal stress partially explain the relatively higher thermal adaptability of indigenous breeds compared to exotic breeds of cattle. ATP1A1 gene is one of such gene that encodes for a1 isomer of Na+, K+- ATPase enzyme for Na+- coupled transport of metabolites, nutrients, ions and represents a plausible candidate for heat tolerance traits. Present study was designed to compare SNP variations in ATP1A1 gene and to evaluate their association with respiration rate, rectal temperature and heat tolerance coefficient in Sahiwal (51) and Karan Fries (50) cows maintained at Livestock Research Centre of National Dairy Research Institute, Karnal. Two SNPs (T27008243C and A27008223G) were identified in both the dairy cattle breeds. Association of each SNP genotype was analyzed using Generalized Linear Model procedure in Statistical Analysis System (SAS). Sahiwal cows with TT (15.91&plusmn;1.89b) at T27008243C locus had lowest RR compared to TC genotypes (18.25&plusmn;1.77ab) and CC genotype (19.24&plusmn;1.52a), while in Karan Fries cows RR for AA genotype at A27008223G locus was lower (28.85&plusmn;1.96b) compared to GG genotype (32.37&plusmn;2.51a). Thus, the study indicated that the TT genotype at T27008243C locus in Sahiwal and AA genotype at 27008223 locus in Karan Fries cows are desirable genotypes for genetic adaptability under heat stress.

Genetic characterization and identification of single nucleotide polymorphisms of ATP1A1 gene in Indian humped cattle

Single nucleotide polymorphisms in ATP1A1 gene and their association with thermotolerance traits in Sahiwal and Karan Fries cattle