Research On Animal Production

     In the current study, phylogenetic analysis and molecular evolution of the mammalian’s Leptin was investigated. Data was achieved and aligned by searching its genome database, while all examined mammals contained only a single copy of the Leptin. The nucleotide substitution rate of the sequences and molecular evolution of the Leptin were calculated by maximum likelihood and neighbor-joining method respectively and phylogenetic tree was constructed. Bioinformatics researches results identified that Leptin genes are distributed across the genome. On the other hand base substitution rate of the pyrimidines to pyrimidines or purines is much more than that of in purines to pyrimidines or purines. The d_N/d_s ratio of the Leptin sequences indicated that Positive selection was accrued during evolution which made new branches to give different responses. This can justifies high polymorphism of the Leptin. Phylogenetic analysis showed that Leptin proteins based on mainly are divided to two clades their evolutionary relationships. In the first clade the protein sequences are divided to mammals and chicken and in the second clade called the others we have all types of fish.