Abstract
Background: In microscopical examinations of stool samples, S. stercoralis may be miss-diagnosed with other nematodes infecting human digestive system, especially Rhabditis species that release larvae in stool samples. The aim of this study was molecular characterization and differentiation of human derived isolates of S. stercoralis and Rhabditis species based on the mitochondrial gene of cytochrome c oxidase subunit 1 (cox1) amplification. Methods: Using parasitological methods, ten isolates of S. stercoralis and three isolates of Rhabditis spp. were obtained from fresh stool samples of patients and the genomic DNA of the samples were extracted. PCR amplification of cox1 gene was carried out for all the isolates and the products were sequenced. Results: The phylogenetic analysis illustrated that S. stercoralis and Rhabditis spp. isolates were placed in two distinguishable separate clades. Inter-species genetic variation between isolates of S. stercoralis and Rhabditis spp. were ranged from 13.5 to 14.5%. Conclusions: Cox1 gene was a suitable marker for discrimination of S. stercoralis from Rhabditis spp. retrieved from human in the current study.
Molecular Characterization of Hard Ticks by Cytochrome c Oxidase Subunit 1 Sequences