Genetic Evaluation and Population Structure of the Gene Locus Involved in Heat Stress (HSP90β) in Native Chickens of Mazandaran, West Azerbaijan and Commercial Chickens

In hot and dry regions, heat stress causes significant economic losses in poultry production and leads to the reduction of several physiological and metabolic factors. This research was conducted in order to investigate the allelic and genotypic polymorphisms of the gene locus involved in heat stress (HSP90β) in native chickens of Mazandaran, West Azerbaijan and commercial broiler and egg-laying chicken populations using PCR-RFLP technique. Randomly, blood was taken from 400 chicken and genomic DNA was extracted by salting out method. The desired gene locus of 494 base pairs was amplified with the help of specific primers and MspI enzyme digestion was used to identify the mutation in the gene locus. For this gene locus, two types of genotypes M1M1 and M1M2 and two alleles M1 (with one band of 494 bp) and M2 (with two bands of 248 bp and 246 bp) were identified. Mazandaran, West Azerbaijan native and commercial broiler chicken masses were in the Hardy-Weinberg equilibrium. For Mazandaran, West Azerbaijan native and commercial broiler chicken populations, Shannon information index was 0.32, 0.28 and 0.40, respectively, the fixation index was 0.12, -0.11 and -0.16, respectively and the observed heterozygosity was 0.19, 0.17 and 0.28, respectively. Due to the presence of polymorphism and mutation in this gene locus, it is possible to use this marker in the native chickens of Mazandaran and West Azerbaijan with genetic selection and in commercial broiler chickens with genetic selection at the line level, to remove heat-sensitive chickens and keep them heat-resistant chickens are used.