Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 15 2 2020 06 08 259 265 Ali Ehsan SHAHBAZI Department of Medical Parasitology and Mycology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran Massoud SAIDIJAM Department of Molecular Medicine and Genetics, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran Amir Hossein MAGHSOOD Department of Medical Parasitology and Mycology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran Mohammad MATINI Department of Medical Parasitology and Mycology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran Moosa MOTAVALI HAGHI Department of Medical Parasitology and Mycology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran Mohammad FALLAH Department of Medical Parasitology and Mycology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran 2020 06 08 Background: Hydatidosis is a cosmopolitan zoonotic infection and Hamadan Province in the west of Iran is one of the most important foci of human hydatidosis in Iran. The aim of the current study was the genetic characterization of hydatid cysts operated from humans in Hamadan Province. Methods: Seventy-two hydatid cysts samples including 50 paraffinized and 22 fresh human hydatid cysts collected from different hospitals in Hamadan Province, western Iran. The cysts' DNA genome was extracted by kit and PCR was performed for amplifying the fragments of 400 and 450bp for nad1 and cox1 mitochondrial genes, respectively. Genotype diversity and sequence variations of the cysts' isolates were studied by related software. Results: DNA from all (100%) paraffinized and fresh hydatid cysts samples extracted successfully. All paraffinized and fresh hydatid cysts samples were amplified by PCR assay using nad1gene, however, only 18 and 8 samples from paraffinized and fresh hydatid cyst samples was amplified using cox1 gene, respectively. The sequences analysis indicated that, 98.61% the Echinococcus granulosus samples were belong to the genotype G1 and 1.39% were G3 genotype. Conclusion: Genotypes of E. granulosus in human samples in Hamadan Province are G1 and G3 and these findings are proved by phylogenic analysis. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/2949 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/2949/1039