Evolutionary and phylogenetic study of Glutathione peroxidase gene in Khazak and Ross 308 populations

Heat stress is one of the most important environmental stressors challenging poultry production worldwide, especially in warm regions such as Sistan and Baluchestan province of Iran. Heat stress increases the production of free radicals in the chicken’s body. Glutathione peroxidase plays important roles as cellular antioxidants in heat stress. The aim of this study was to conduct an analysis of the evolutionary and phylogenetic of GPX-1 in Ross 308 and Khazak populations. Boold samples were collected from 10 birds selected randomly from two stocks of Khazak and Ross 308 population (5 Ross 308 and 5 Khazak birds). DNA was extracted from whole blood. PCR amplification of 800 bp of GPX-1 was performed using one pairs of special primers. Then, PCR product sent for DNA sequencing. Sequence alignment of the GPX-1 fragment revealed a total of 9 haplotypes and 13 variable sites. Out of 13 polymorphic sites, 5 were singletons. Dendrogram of phylogenetic showing genetic similarity between the two populations, but probably diversity within populations indicate the possibility to improve genetic changes and increase the resistance to environmental stresses using selection. The results of genetic distance and polymorphic site of GPX-1 in different species approved phylogenetic tree findings. Study of positive- selection process showed that selection and evolution are playing major roles in understanding the biological function of this gene