Molecular Characterizationand Phylogeny of Taenia hydatigena and Echinococcus granulosus from Iranian Sheep and Cattle Based on COX1 Gene.

Abstract

Hydatid cyst, the larval stage of Echinococcus granulosus, and Cysticercus tenuicollis, the larval stage of Taenia hydatigena, are prevalent in domestic, livestock, and wild ruminants. The main goal of this research was to identify the isolates of E. granulosus and C. tenuicollis by partial sequencing with PCR amplification of the cytochrome C oxidase 1 (COX1) gene. During a routine veterinary inspection at a Chabahar city slaughterhouse, two samples of hydatid cysts from sheep's liver and cattle's lung and two samples of C. tenuicollis from sheep's liver were collected. After DNA extraction, the fragment of the COX1 gene was amplified by the PCR method. Sample sequences were modified and synchronized by Chromas and CLC genomic workbench 11 software. Sequence analysis was carried out by BLAST algorithms and GenBank databases. Phylogenetic trees were performed using MEGA 7 software and the neighbor-joining and maximum likelihood method for T. hydatigena and E. granulousus. The result indicated that the main genotype of parasites and the amplified fragment size were G1 and approximately 455bp, respectively. The analysis of phylogenetic trees based on nucleic acid for four samples showed that there was a common ancestor. However, the shift in nucleotides in the two isolates in E. granulosus and the two isolates of T. hydatigena were non-synonymous type and synonymous type, respectively. The present study showed that the dominant genotype in all isolates was G1 and this report was similar to other studies in Iran and the world. Also, the partial COX1 gene sequence was matched with T. hydatigena.