Abstract:

The aim of the current study was to investigate the genetic polymorphisms of Echinococcus granulosus obtained from sheep in Qinghai Province, and provide the foundational data for prevention and control of echinococcus disease. The complete mitochondrial DNA 12S genes of 42 isolates（33 were from liver and 9 were from lung）were sequenced, and phylogenetic analyses were conducted using neighbor-joining tree-building methods. There were five haplotypes (H₁ to H₅) detected among the samples, and H₅ was the main type. Phylogenetic analysis supported these observations. The haplotype diversity (H) and nucleotide diversity (Pi) were 0.418 and 0.000 66, respectively. It was demonstrated that the genetic homology of these isolates with the 12S gene of E. granulosus G1 genotype（AF297617）was over 99.86%. All 42 samples were identified as E. granulosus sensu stricto (G1-G3 clusters). In this study，genotypes H1 to H₄ has not been identified elsewhere.