Polymorphic Analysis Of COI Gene And NDI Gene Of Mitochondrial DNA Of Echinococcus Spp. In Qinghai Province

To get the molecular genetic information and identify the species withinEchinococcus genus, finally to make sure the infection status of Echinococcus spp. inthe main final host, like wild foxes and Tibetan dogs, in Qinghai Province.Echinococcus spp. were sampled. Normal PCR method was applied and then thepolymorphisms analysis of COI gene and NDI gene of Echinococcus spp. wasconducted directly after been sequenced.363bp long fragments of COI gene were obtained from22isolates sampled. Theresults of alignment of22mtDNA COI gene sequences show that the genotype of10isolates were Echinococcus granulosus I（E.granulosus G1）,8isolates wereEchinococcus multilocularis,（E. multilocularis）, and4isolates were Echinococcusshiquicus,(E.shiquicus). The homology analysis showed that the similarity ofE.granulosus G1strains were from99.2%to100%, while that of the E. multilocularisstrains were from98.7%to100%and that of the E.shiquicus strains were from99.2%to99.8%. It was shown86.8%～89.2%similarity with E.granulosus G1and E.multilocularis, and88.3%～89.5%similarity with E.granulosus G1and E.shiquicusstrains, the homology similarity between E.shiquicus and E. multilocularis strainswas88.1%～90.1%. There were6different sequences for E.granulosus G1genotype,which involved5base mutations and made up1.38%of total gene. Haploid sequencedifference value are from0to0.8%. E. multilocularis were checked4differentsequences with5nucleotide mutation points, which were made up1.38%of the totalgene, the haploid sequence are different from0.2to0.8%. And there were4differentsequences for E.shiquicus, which was checked6different nucleotide mutation pointsand made up1.65%of the total gene, and the haploid sequence are different from0.2%to0.8%. Intra-Specific mutation rate was less than1.3%, and inter-specific mutation rate was more than9.9%.507bp long fragments of NDI gene were obtained from21isolates. The results ofalignment of our22mtDNA NDI gene sequences show that the genotype of10isolates were E.granulosus G1,8of isolates were E. multilocularis, and4of isolateswere E. shiquicus. There were6different sequences for E.granulosus G1genotype,and the10nucleotide mutation points were made up to1.97%of the total gene,haploid sequence differences are from0to1.0%. E. multilocularis were checked6different sequences, and the9base mutation points were made up1.76%of the totalgene, the Haploid sequences are different from0%to0.8%. While there were4different sequences for E. shiquicus, which was checked12different nucleotidemutation points made up2.37%of the total gene, and the difference value of Haploidsequence are from0%to1.18%. Intra-Specific mutation rate was less than1.0%, andinter-specific mutation rate was more than15.6%.