Analysis On Genetic Diversity And Sequencing GH Gene In Chinese Large Size And Middle-sized Donkey Breeds

China is one of the biggest countries that have many donkeys. The resource of donkey is rich and the biological style is diversiform. But the research on property and genetic relationship between breeds were rare, especially on the level of molecular. In this study, twenty-nine microsatellite loci were used to analyze genetic variation and population structure of China large size and middle-sized donkey. Besides, the GH gene of donkey was sequenced and analyzed.First, twenty-nine horse microsatellite loci were used to analyze genetic variation between and within China large size and middle-sized donkey population and the 29 microsatellite loci's genetic variations in China large size and middle-sized donkey population were discussed. The results were as follows:1. In this research, forty-two microsatellite loci were selected for amplifying genomes of eight china middle-type and large type donkey populations. Among the loci, there were twenty-nine loci have clear brands and present rich polymorphism, so they can be used for genetic diversity analyses.2. The twenty-nine loci used for donkey genetic diversity analyzing has rich number Of allele, each locus was with number of alleles detected 5¹4 and each population was 2¹3. The eight populations have 261 alleles. There were nine private alleles in them. The microsatellite locus NVHEQ18 was middle polymorphic (0.335), and the others were highly polymorphic. Twenty microsatellite locus were with PIC higher than 0.7, so they could be used for linkage analyses. Allele average effective number of alleles was 1.66-5.67, allelic richness 4.681-9.985, average polymorphic information content 0.335-0.818, overallheterozygosity (H_t) 0.384-0.849, average heterozygosity within population (H_s) 0.359-0.843, andobserved heterozygosity (H₀) 0.111-0.548. LEX003 had the highest mean allelic number and generichness,TKY321 had lowest; UCEDQ505 has the biggest PIC, H, and Hs values, NVHEQ18 had least. Among these eight breeds, Jinnan donkey has the highest PIC and H, Dezhou donkey has the most effective alleles and huaiyang donkey has the lowest PIC, H and effective allelic number.3. Genotypes at each locus in the most of populations deviated from Hardy-Weinberg equilibrium. In linkage equilibrium test, except for linkage disequilibrium between HMS7 and ASB41, the other loci situated on one chromosome are in linkage equilibrium. Some loci in different chromosomes were also in linkage disequilibrium. Under TPM model for microsatellite by wilcoxon sign-rank two tail test, jinnan , huaiyang and dezhou donkey showed significant excessive hybrids. So we got that qingyang, .guanzhong> jiami guangling and biyang were in mutation-drift equilibrium and had not been significantly influencsd by bottleneck effect.4. Significant (p<0.05) genie and genotypic differentiations between most of populations were found, indicating the distribution of alleles and genotypes were different among populations. The statistics forcoefficient of gene differentiation at each locus, G_st, G'_st and 9 ranged in -0.004⁰.088, -0.004⁰.099 and -0.055⁰.073 with overall mean 0.025, 0.028 and 0.027, respectively, indicating that 2.5% 2.8% and about 97% of total variation were from between and within population variations, and thoseunder SMM model, R_st,, ranged in -0.012⁰.130 with the overall mean 0.0326.5. Relatedness computed based on each locus were small positive with overall mean 0.028 and negative with overall mean -2.91 for not correction and correction for inbreeding respectively. The more...