Determination of polymorphisms in the HSP90AA1 gene region in some Turkish sheep populations by AS-PCR

Abstract

Heat shock proteins (HSPs) are molecular chaperones protecting living cells from the negative effects of extreme ambient temperatures. In this study, genetic polymorphisms of the HSP90AA1 gene were monitored via Allele-Specific Polymerase Chain Reaction (AS-PCR) in three native Turkish sheep populations namely İvesi (IVS), Güney Karaman (GKR), and Karakaş (KRK). The HSP90AA1 was polymorphic in all populations yielding two alleles (C and G) and three genotypes (CC, CG, and GG). The G allele frequency was higher than the C allele frequency in all populations. The lowest (0.100) and highest (0.246) CC frequency was observed in KRK and IVS, respectively, while the GG genotype frequency varied between 0.250 (GKR) and 0.600 (KRK). Significant deviation (p<0.001) from Hardy-Weinberg Equilibrium (HWE) was detected in the IVS breed in terms of the HSP90AA1 gene. The genetic distance-based phylogenetic tree indicated that GKR was genetically different from IVS and KRK populations in terms of the HSP90AA1 polymorphism. These variations regarding the HSP90AA1 gene should be conserved, since the negative effects of global warming and climate change are expected to be more hazardous in the future. Besides, these genetic variations may be utilized by the farmers to design comprehensive selection strategies against heat stress in native Turkish sheep populations.