Designing and conducting in silico analysis for identifying of Echinococcus spp. with discrimination of novel haplotypes: an approach to better understanding of parasite taxonomic

Abstract

The definitive identification of Echinococcus species is currently carried out by sequencing and phylogenetic strategies. However, the application of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) patterns is not broadly used as a result of heterogeneity traits of Echinococcus genome in different regions of the world. Therefore, designing and conducting a standardized pattern should indigenously be considered in understudied areas. In this investigation, an in silico mapping was designed and developed for eight Echinococcus spp. on the basis of regional sequences in Iran and the world. The numbers of 60 Echinococcus isolates were collected from the liver and lungs of 15 human, 15 sheep, 15 cattle, and 15 camel cases in Semnan province, Central Iran. DNA samples were extracted and examined by polymerase chain reaction of ribosomal DNA (rDNA) internal transcribed spacer 1 (ITS1) and PCR-RFLP via Rsa1 endonuclease enzyme. Moreover, 15 amplicons of cytochrome oxidase 1 (Cox1) were directly sequenced in order to identify the strains/haplotypes. PCR-RFLP and phylogenetic analyses revealed firmly the presence of the G1 and G6 genotypes with heterogeneity (three novel haplotypes) of Cox1 gene although no other expected genotypes were found in the region. Finding shows that the identification of novel haplotypes along with discrimination of Echinococcus spp. through regional patterns can unambiguously illustrate the real taxonomic status of parasite in Central Iran.