The Genetic Diversity Of Microsatellite DNA For Six Native Goat Breeds In China

The genetic diversity of six native goats in China was surveyed using nintheen microsatellite loci.The six goats included Licheng cyan goat,lvliang black goat,Yangcheng white goat, Xinjiang goat in North, Xinjiang goat Sourth,Zhongwei goat.And the results were as follows:1. The 19 microsatellite loci were seleted and the results of PCR were got in every locus.177 allelic were got in all the loci and the average number was 9.3 in one locus and the lest one was 6. All the loci could be used to analyse the genetic diversity of every breed.The effectiveallelic number wab 76 which was less than the observed allelic number.2.The Hardy-Weinberg equilibrium analysis revealed that 6 breeds showed a remarkable genetic disequilibrium at all the loci.Maybe the reasons were that the size of the samples were less or in breeding existed in 6 breeds.3.The 19 microsatellite loci showed middle high and high PIC value.The mean PIC value was between 0.6859-0.7083,which indicated that the 6 breeds had abundant genetic diversity. The mean heterozygosity was between 0.3832-0.4277.4.The Cofficient of gene differentiation was largest in BM203, BM023, BMS6526, MAF65 loci.The Gst of other loci was not larger and the one of BM3033 was 0.The result showed that the gene differentiation was in every breeds and not remarkable in all the breeds.5.Nei's genetic distance and Coancestry genetic distance were estimate and used to construct UPGMA and NJ dendrograms.In the UPGMA and NJ dendrogram based the Nei'S genetic distance,lvliang black goat and the Yangcheng white goat were one cluster which was consistent with the former's research. The UPGMA and NJ dendrograms based the Coancestry genetic distance had the difference with the former's.But the 4 dendrograms showed that Xinjiang goat and the Shan'xi goat had the possibility that they had had common ancestor.6. Based the allele frequencies of 17 microsatellite loci,the accuracy of Nei's standard distance among 4 china domestic goats are analysed when 3,6,9.12 and 15 micrisatellite loci.The results indicate that :with the numbersof the loci increased,the accuary of genetic distance estimation increase too.The result of "t" test is that there is remarkable difference between every two levels except 6 and 3.When the experiment is designed to analyse genertic rekationship between different species,small mumber should not be used.