Genetic Polymorphism Study On Cytb And D-loop Gene Sequence Of Mongolian Wild Horses

Mongolian wild horse is very old,and so far,it is the only persevered wild horse.over the years.there have different opinion on assortment and evolutionary relationships between Mongolian wild horse and Mongolian domestic horse, and it is very important to study evolutionary relationships between them in molecular lever, also can provide reliable theory basis for Genetics and Breeding.The paper, amplified mitochondrial Cytochrome b and D-loop sequences in the Mongolian wild horse genome by PCR technique,through Purification Recycling,then did Evolution analysis. And there have not any detailed report on genetic differences and Evolution relationships between Mongolian wild horse and Mongolian domestic horse.Therefor, the author respectively downloaded24mitochondrial Cytochrome b genes and D-loop sequences,to analyses and discusses the relationship of Mongolian wild horse and Mongolian domestic horse.On the basis of Cytochrome b genes sequences, the analysis results show that:(1)To contrast Cytochrome b genes sequences of Mongolian wild horse and Mongolian domestic horse,we found that90mutant sites constitute15Haplotypes, and there have2sharing Haplotypes. It shows that the relationship between them is close.(2)According to the Mismatch Distribution of Neutral tests and construction found that their Neutral tests value is not in significance level,and the Mismatch Distribution is polymodal curve.it shows that Mongolian wild horse and Mongolian domestic horse have not experienced Population expansion and the population is remain stable.(3) According to construct UPGMA phylogenetic tree and Median Joining Network by MEGA5and Network software,found that Mongolian wild horse and Mongolian domestic horse get together in UPGMA phylogenetic tree, and their subject Haplotypes distributed in sharing Haplotypes in Network, the result shows that their relationship is close, and conjectures Mongolian wild horse is the ancestor of partly Mongolian domestic horse.On the basis of D-loop sequences the analysis results show that:(1)Totally detect74mutant sites constitute24Haplotypes, Mongolian wild horse and Mongolian domestic horse sharing2Haplotypes. it shows that their relationship is close.(2)According to ML and MP phylogenetic tree which is builded by MEGA5software,find that Mongolian wild horse and partly Mongolian domestic horse gathered,show that their relationship is close.it also can conjecture that Mongolian wild horse is the ancestor of partly Mongolian domestic horse,and the results have not difference between this two kinds of phylogenetic trees.(3)Calculate genetic distance between Mongolian wild horse and Mongolian domestic horse,then on the basis of Molecular clock theory conjecture that the Divergence time took place in0.34-0.67million years ago, and the average genetic distance between them is0.0247. According to genetic distance of interspecific crossing in Equidae is0.115-0.133,show that the distance between Mongolian wild horse and Mongolian domestic horse have not reached specific differences,and they belong to the same specific.