Study On Polymorphism Of Taenia Asiatica In Qinghai-tibet Plateau

?Objectives?This study focuses on the Echinococcus granulosus in the Tibetan Plateau and Echinococcus tapeworm as the research object,study on gene polymorphism of Echinococcus collected from patients infected with Echinococcus granulosus in the Tibetan Plateau,by the use of mitochondrial cytochrome c oxidase subunit gene(COX1)and nicotinamide adenine dinucleotide(dehydrogenase subunit gene(NAD1)).The genotype and its genetic variation of Echinococcus were determined unequivocally as well as the phylogenetic tree was constructed.In oerder to master the number of popular species and the gene sequence polymorphism of the Echinococcus,guide the clinical diagnosis and treatment,and to provide theoretical guidance for the prevention and control of Echinococcosis.?Methods?The Cystica of 172 patients with Echinococcosis were collected,the cystica and it's DNA were extracted and purified.The COX1 gene and NAD1 gene of mitochondrial DNA were selected as the specific primers,amplified by PCR and sequenced the PCR products.The genotype and gene polymorphism of the epidemic strains of Echinococcus were analyzed,and the phylogenetic trees were constructed by using the genes,to study the genetic diversity and genetic evolution of Echinococcus granulosus in the Tibetan Plateau.?Results?The results of this paper are as follows:The isolated cysts were identified by molecular biology methods,which were G1 type,which indicated that the epidemic strains of Echinococcus granulosus in the Tibetan Plateau was the Echinococcus granulosus(G1 type).The sequence length of COX1 gene and NAD1 gene of G1 type Echinococcus were 1674 bp and 894 bp,respectively.The isolates of Echinococcus were collected for extracting DNA and NAD1 and COX1 gene amplification and sequence analysis,found that the main advantage strains of the Echinococcus granulosus in the Tibetan Plateau is G1.The results showed that there were 14 different sequences and 20 mutations in the NAD1 gene,accounted for 2.2%.COX1 gene there are 18 different sequences,45 mutation sites,accounting for 2.7% of the number of analysis sites.Base changes are transitions and transversions,and transitions are significantly more than transversion.There were no significant differences in gene sequences in the gene sequence analysis of 172 isolates.Homology analysis of 136 amplified gene sequences,the homology of NAD1 gene was higher than 98.88% that compared with the common sheep(AF297617)in Gen Bank,and the homology of COX1 gene was more than 99.82%.The haplotype analysis of NAD1 and COX1 genes in the G1-type Echinococcus multilorillas isolates of the Echinococcus granulosus in the Tibetan Plateau showed little difference in nucleotide sequence.There were 14 different genotypes haplotypes of 136 strains of gliobacillus echinococcus.The nucleotide sequence of the NAD1 gene was occurred T and C replacement at 117,and the nucleotide sequence of COX1 gene was occurred T and C replacement at 426,429,456,which was the most important in G1 type Echinococcus granulosus haploid.?Conclusions?The predominant strains of Echinococcus granulosus in the Tibetan Plateau were the G1 type of Echinococcus granulosus and the COX1 gene had a rich haplotype polymorphism compared with NAD1 gene.The COX1 gene and NAD1 gene confirmed that the mutual difference of nucleotide sequence of G1 type Echinococcus in Echinococcus granulosus in the Tibetan Plateau was small.The results of the above studies have provided data for the further development of molecular epidemiology of Echinococcus granulosus and the reference for the control of hydatid disease in the Qinghai-Tibet Plateau.