Comparative Genotyping of <i>Echinococcus granulosus</i> Infecting Livestock in Turkey and Iran

Abstract

Amaç: Echinococcus granulosus, yaşam döngüsü paterni ve konak tiplerine göre çeşitlilik gösteren farklı suşlara sahiptir. Şimdiye kadar bu parazitin 10 genotipi, moleküler yöntemler kullanılarak tespit edilmiştir. Bu çalışmada, Türkiye ve İran'daki hayvanlarda E. granulosus metasestodlarının genotipik çeşitliliğinin değerlendirilmesi ve karşılaştırılması amaçlanmıştır. Yöntemler: İran'ın Doğu Azerbaycan eyaletindeki Bonab şehrindeki (30 koyun ve 30 sığır dahil olmak üzere 60 örnek) ve Türkiye'nin Van şehrindeki (15 koyun ve 15 sığır dahil olmak üzere 30 örnek) endüstriyel kesimhanelerinden hidatik kist ile enfekte Objective: Echinococcus granulosus contains a complex of different strains that represent diversity in the pattern of the life cycle and also their host types. So far 10 genotypes of this parasite have been identified, using molecular methods. The current study aimed to evaluate and compare the genotypic diversity of E. granulosus metacestodes from livestock of Turkey and Iran. Methods: A total of 90 livestock liver and lung organs infected with hydatid cyst from industrial slaughterhouses of Bonab Province in the East Azerbaijan Province in Iran (60 samples, including 30 sheep and 30 cattle) and Van Province in Turkey (30 samples, including 15 sheep and 15 cattle) were collected. DNA was extracted from the protoscolices or germinal layers and polymerase chain reaction (PCR) were utilized, targeting the partial mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase 1 (nad1) genes. PCR products were isolated from the electrophoresis gels and sequenced. The sequences were compared with each other, as well as with those related available sequences in the GenBank, using the BioEdit software and the BLAST algorithm. Finally, the phylogenetic trees were constructed by comparing sequences of cox1 and nad1 fragments, using the MEGA7 software and the maximum likelihood method. Results: All samples sequenced from Iran corresponded to the genotype G1 (100%). Among the samples from Turkey, 15 samples (78.9%) were identified as G1 while only one sample (5.3%) corresponded to the genotype G3 and 3 isolates (15.8%) were defined as genotypes G1/G3. Five distinct haplotypes were determined within the examined isolates from sheep and cattle in both countries and all isolates clustered in one group. Phylogenetic analysis revealed that the intra-species genetic variations were 0.0-0.6% and 0.0-1.4% for cox1 and nad1, respectively. Conclusion: The dominant genotype of E. granulosus sensu stricto of livestock in both countries was the G1 (sheep strain) genotype. Our findings indicate that the sheepdog cycle is the leading cycle of E. granulosus in these two areas. Hence, adopting regional common policies and bilateral cooperation helps to control the disease in livestock as well as in human in these two regions. Further study is required to compare the genetic diversity of human isolates of E. granulosus in these two countries.

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

“…The study was performed on hydatid cyst samples collected from three regions: Van province from Turkey, located in the east of Van Lake, which is a part of the coldest region in Turkey; East Azerbaijan province as a cold area, located on the mountain range of Iran in the southeast of Urmia Lake; and Fars Province in southern Iran (Table 1). Fars Province has a completely different geographical and climatic condition in comparison with the other two areas in Iran and Turkey, but all three areas have always been considered endemic areas for human CE [5,8,[24][25][26][27].…”

“…genotypes G6/G7 and G8/G10 can be regarded as two distinct species [ 4 ]. The most common hydatid cyst genotypes reported worldwide are two closely related genotypes, G1 and G3, of the sensu stricto strain [ 5 – 7 ].…”

“…Iran and Turkey are considered highly endemic areas for hydatid cysts in both humans and animals [ 6 , 17 – 24 ]. In our previous studies on isolates of E. granulosus s.s. from livestock and human populations from Iran and Turkey, different genotypes of the parasite were identified based on cox 1 and nad 1 genomic fragments [ 5 , 8 ]. However, since the genomic fragments used in our previous studies were not able to differentiate between the G1 and G3 genotypes, the present study was performed using specific primers and targeting the nad 5 genomic fragment to determine the G1/G3 genotype of E. granulosus s.s. isolated from livestock and human samples from Azerbaijan and Fars Provinces in northwestern and southern Iran, and Van Province in eastern Turkey.…”

Genetic Diversity of Echinococcus granulosus Isolated from Humans: A Comparative Study in Two Cystic Echinococcosis Endemic Areas, Turkey and Iran

“…It has also been documented that different strains of E. granulosus have a tendency to infect specific organs of the body and even each genotype of the parasite may have the propensity to infect a particular intermediate host. Therefore, by identifying the dominant genotypes of E. granulosus in a given geographical area, proper planning can be done to prevent parasite transmission between intermediate and definitive hosts and to prevent the transmission of the disease to humans [16,17].…”

Comparison of various methods for DNA extraction from human isolated paraffin-embedded hydatid cyst samples

“…It is known that E. granulosus has different genotypes, which can affect life cycle pattern, epidemiology and pathogenicity of hydatid cysts (Bowles et al 1992;Khosravi et al 2012;Sharbatkhori et al 2009;Barazesh et al 2019), as it is proved that some of the strains are more virulent in humans and also tend to be specific organs of the host body (Gholami et al 2011). Therefore, determining the dominant genotypes of the parasite in different regions and subsequently, providing appropriate and effective therapeutic strategies is of particular importance (Barazesh et al 2019;Kheirandish et al 2018;Ahmadi and Dalimi 2006).…”