Sequence analysis of cox1 and nad1 genes in Echinococcus granulosus G3 genotype in camels (Camelus dromedarius) from central Iran.

Nineteen hydatid cyst isolates collected from camels in central Iran were subjected to sequences analysis of mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes. A consensus sequence obtained containing 366 nucleotides for cox1 and 471 nucleotides for nad1 genes. Overall, the camel isolates indicated five different sequences in cox1 and nine in nad1 genes. The sequences analysis indicated that 26.3%, 42.1%, and 31.6% of isolates belonging to G1, G3, and G6 genotypes of Echinococcus granulosus, respectively. The isolates with G3 genotype indicated one cox1 sequence having 100% homology with reference G3 sequence (AN: M84663) and two different nad1 sequences, one having 100% homology with reference G3 sequence (AN: AJ237634) and the other with a silent mutation (G to A) in position 279. The presence of G3 genotype (buffalo strain) of E. granulosus as dominant genotype in camels is emphasized. As G3 genotype has formerly been reported in human, the epidemiological role of camels is warranted in future surveys.