Sequencing and phylogenic variation of ITS-2 region and rrnL gene in Toxocara canis of Iraqi isolation

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Research Paper 01/07/2018
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Sequencing and phylogenic variation of ITS-2 region and rrnL gene in Toxocara canis of Iraqi isolation

Balkes Fadel Hade, Shurook M. K. Saadedin, Amer Murhum Abd Al-Amery, Halah Khalid Ibrahim
J. Bio. Env. Sci.13( 1), 72-83, July 2018.
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Toxocara canis nematode roundworm, the main causative agent of zoonotic disease of canids and Toxocariasis in humans.This study designed to detect the ITS-2 region and rrnL gene Iraqi isolate and to characterize and analyse the genetic variation inT. canis  adult nematode which collected from puppies in different geographical areas of Baghdad city. DNA extracted from worms then detected by PCR followed by sequencing and phylogenetic tree analysis using BLASTed sequences (Neighbor-Joining method) and program(Advance method). Two aligned sequences namely Balkes I (Ba I) for (ITS-2) region and Balkes II (Ba II) for (rrnL) gene were deposited in NCBI with accession numbers LC328970, LC328971, respectively and at DDBJ and ENA database for the first time in Iraq. BLASTed sequences results indicate clustered the aligned sequences of Ba I and Ba II with T. canis specie other than Toxocara species with low genetic changes (0.08) and (0.04) respectively, while phylogenetic analysis results indicated that Iraqi Ba I and Ba II aligned sequences are clustered with other sequences of T. canis isolates retrieved from databases and recorded low genetic changes of (0.05) and (0.007).The current study concluded that the ITS-2 region and rrnL gene can be used as genetic markers for studying specific genetic identification and diagnosis and study genetic variation of ascaridoid nematodes.


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