A Molecular Study on Sheep, Camel and Human Isolates of Echinococcus Granulosus in Iran, using PCR Technique

The present work conducted in order to identify either heterogeneity or homogeneity among sheep, camel and human isolates of Echinococcus granulosus using the PCR technique. A total of 78 isolates of hydatid cyst of E. granulosus, including 35 isolates from sheep, 32 isolates from camel and 11 isolates from human of various regions in Iran were examined. A single material from an individual hydatid cyst was considered as an isolate. the DNA was extracted from frozen, ethanol preserved or freshly obtained protoscoleces by standard method of SDS and proteinase K treatment, phenol/chloroform extraction and ethanol precipitation. The PCR amplification was performed using BDI and 4S primers in the ITSI region of the rDNA of the parasite.The PCR products were electrophoresed through agarose gel and stained with ethidium bromide. After the PCR amplification, the rDNA-ITSl from all sheep, camel and some human isolates gave very similar pattern on agarose gel, although the rDNA-ITSl from 4 human isolates showed different pattern. In this regard, the approximate size of fragments from all isolates were found to be 1000 bp, except in 4 human isolates in which the fragments were of 700 bp. The present data supports the probable existence of at least two separate strains of E.granuIosus, which can infect human in Iran.