Analysis Of Genetic Diversity Of Six Horse Breeding Population By SSR

The genetic diversity of 9 microsatellite loci was analyzed with the microsatellite marker technology in six horse populations. The six populations concluded:Wuzhumuqin horses (WZ),Wushen horses (WS),Xinihe horses (XN),Baerhu horses (BH),Sanhe horses (SH) and Thoroughbred horses (CX). The objective of this study were to provide scientific accordance for conserving and utilizing genetic resource of horses.The results were as follows:1. The 9 microsatellite loci were selected and the results of the PCR in 305 samples of the 6 horse populations were got in every locus. 99 alleles were tested in all the loci and the mean allelic number of per locus was 11,the least locus was 5.5. The efficient allelic number was 53.44. The efficient allelic number was less than the observed allelic number,this was the result of the alleles distributing unequally. And the dominant allele was analyzed,the results showed that the dominant allele was existed in all loci.2. The Hardy-Weinberg equilibrium analysis revealed that remarkable genetic disequilibrium was showed at all the loci in 6 horse populations. The reasons may be that the excursion occurred in random mating,the random genetic drift and breeding was existed in 6 populations.3. The mean heterozygosity varied from 0.5839 to 0.8166 across all losi,and PIC value varied from 0.5093 to 0.8430,all loci were highly diverse,except ASB18 in Thoroughbred horses (CX) and UM022 in Wuzhumuqin horses (WZ),Sanhe horses (SH),Thoroughbred horses (CX) were middle diverse.4. The result of the coefficient of gene differentiation showed that 4.79% of total variation were from between population variations.5. The F-statistic analysis indicated that the FST of different locus varied from 0.0278 (in ASB2) to 0.0778 (in UM022).The number of migrants per generation (Nm) was from 2.9618 to 8.7303,with a mean value of 4.7565.6. The UPGMA and NJ phylogenetic trees constructed with the Dcoa genetic distances between the 6 horse breeds supported a closer relationship between Wuzhumuqin horses and Wushen horses(WS).