[Objective] The paper aimed to reveal the genetic diversity of large and medium-sized donkey breeds of China.[Method] The genetic polymorphisms of 24 microsatellites in the eight large and medium-sized donkey breeds were studied by means of PCR,polyacrylamide gel electrophoresis and silver staining.[Result] The microsatellite of NVHEQ18 was medium polymorphic and the other 23 microsatellite loci were highly polymorphic.The average PIC（0.694 0）,H（0.711 9）and E（2.9）of the eight donkey breed populations were all high,indicating that the gene polymorphisms and genetic diversity were relatively high.[Conclusion] The 24 microsatellite loci were effective markers for analysis of genetic relationships among the donkey breeds.The phylogenetic relationships among large and medium-sized donkey breeds were in accordance with their breeding history and distribution.
[Objective] The paper aimed to study the donkey GH gene features and functions.[Method] A pair of specific PCR primers was designed for cloning the coding sequence of the donkey GH gene from liver tissue.[Result] 706 bp fragment was got by RT-PCR amplification.The sequence included a complete open reading frame and encoded 216 amino acids.The protein encoded by donkey GH gene had seven hydrophobic region,seven transmembrane regions and a signal peptide;it＇s secondary structure had α-helix and irregular curl and three-dimensional solution structure composed of 27-215 amino acids.[Conclusion] GH gene of donkey was very conservative in evolution.The phylogenetic tree constructed basing on CDS sequence is consistent with the results of comparative morphology and comparative physiology.
