Echinococcus granulosus sensu stricto G1 is the predominant genotype in human and livestock isolates from Turkey and Iran, based on mitochondrial nad5 gene differentiation

Saeed Shahabi,Afshin Barazesh,Bahador Sarkari

doi:10.1186/s13071-021-04869-1

Saeed Shahabi, Afshin Barazesh + Show 1 more

Open Access

https://doi.org/10.1186/s13071-021-04869-1

Copy DOI

Abstract

BackgroundDifferent genotypes of Echinococcus granulosus sensu stricto (s.s.) isolated from livestock and humans have been identified based on cox1 and nad1 genomic fragments. The present study was performed to differentiate the G1/G3 genotypes of Echinococcus granulosus (s.s.) isolated from humans and livestock (sheep and cattle) from Azerbaijan in northwestern Iran, Fars Province in southern Iran, and Van province in Eastern Turkey, using the nad5 gene fragment as a suitable marker to distinguish these two genotypes.MethodsA total of 60 pathologically confirmed human hydatid cysts and 90 hydatid cyst samples from livestock were collected from Turkey and Iran. PCR was performed on all of the samples, targeting the nad5 gene. Based on PCR product quality, host type, and the geographical area where the samples were obtained, 36 of the samples were sequenced and were used in the phylogenetic analysis.ResultsOut of 36 evaluated samples, 26 (72.2%) samples belonged to G1, and 10 (27.8%) samples belonged to the G3 genotype. Out of 21 samples from Turkey, 16 (76.2%) were G1 and 5 (23.8%) were G3, while out of 15 samples from Iran, 10 (66.7%) were G1 and 5 (33.3%) were the G3 genotype. None of the samples isolated from humans in Iran or from sheep in Turkey were G3. Overall, between the two countries, 18.18% of E. granulosus isolates in cattle, 41.66% of isolates in sheep, and 23.07% of human samples were identified as G3, and the others as the G1 genotype. The G3 genotype was not detected in human samples from Iran or sheep samples from Turkey.ConclusionThe findings of the study revealed that the G1 genotype of E. granulosus s.s. is the predominant genotype in humans and livestock, both in Turkey and Iran. The ratio of the E. granulosus s.s. G1 to G3 genotype was 3.2 in Turkey and 2 in Iran. The study also further confirmed that the nad5 gene properly differentiated the G1/G3 isolates of E. granulosus from both humans and livestock.Graphical

Highlights

Different genotypes of Echinococcus granulosus sensu stricto (s.s.) isolated from livestock and humans have been identified based on cox1 and nad1 genomic fragments
The names for genotypes G6–G10, including E. canadensis and E. intermedius, are still under dispute, as recent molecular phylogenetic analysis based on six nuclear genes suggested that E. granulosus s.l. genotypes G6/ G7 and G8/G10 can be regarded as two distinct species [4]
The nad5 genomic fragment was used to differentiate between G1 and G3 genotypes in hydatid cysts isolated from humans and livestock in Iran and Turkey

Summary

Introduction

Different genotypes of Echinococcus granulosus sensu stricto (s.s.) isolated from livestock and humans have been identified based on cox and nad genomic fragments. The present study was performed to differentiate the G1/G3 genotypes of Echinococcus granulosus (s.s.) isolated from humans and livestock (sheep and cattle) from Azerbaijan in northwestern Iran, Fars Province in southern Iran, and Van province in Eastern Turkey, using the nad gene fragment as a suitable marker to distinguish these two genotypes. A variety of mitochondrial genes, including cox, nad, and atp or a fragment sequence of the 12SrRNA gene, as well as the internal transcribed spacer (ITS1) genomic region, have been utilized in various studies for the phylogenetic analysis of E. granulosus [8,9,10,11,12]

Methods

Results

Conclusion