Genetic Diversity In Liangshan Semi-fine Wool Sheep Population By Microsatellite DNA Markers

Genetic diversity of Liangshan Semi-fine Wool Sheep Population was evaluated on the basis of 13 microsatellite markers selected from the sheep linkage map. Allele frequencies of 13 microsatellites were estimated based on genotype measured using Genscan 2.0. Ploymorphism information content (PIC) and heterozygosity were calculated based on allele frequencies. Some problems use the microsatellite markers in the study of population genetic diversity were discussed.Thirteen microsatellite loci analyzed were polymorphic in this flock with an average number of alleles per loci, the average polymorphism information content (PIC) and heterozygosity are 11.1 ( from 5 to 18 ), 0.609 ( from 0.309 to 0.825 ) and 0.504 ( from 0.408 to 0.549 ) respectively. Polymorphism of every microsatellite in this flock is different with result in the Gene-bank. These different were probably result from microsatellite primer for multiple PCR reaction and experimental population different from the result in the Gene-bank.All calculated parameters were different. The significant higher heterozygosity suggested that Liangshan Semi-fine Wool Sheep Population had abundant genetic diversity and potential of selection. This result accorded with the expectation derived from the morphology and the breeding history of Liangshan Semi-fine Wool Sheep. This study suggested that microsatellite DNA marker is a useful tool in detecting genetic diversity in closely related breeds and accessions. To reach a accurate result, all the markers to be used in a study must be selected properly, and the genetic variations from much loci in genome will be needed to get enough information in similar study in the future.