Acta Parasitologica

, Volume 62, Issue 3, pp 549–556 | Cite as

Differentiation of Toxocara canis and Toxocara cati based on PCR-RFLP analyses of rDNA-ITS and mitochondrial cox1 and nad1 regions

  • Fattaneh Mikaeili
  • Alexander Mathis
  • Peter Deplazes
  • Hossein Mirhendi
  • Afshin Barazesh
  • Sepideh Ebrahimi
  • Eshrat Beigom KiaEmail author


The definitive genetic identification of Toxocara species is currently based on PCR/sequencing. The objectives of the present study were to design and conduct an in silico polymerase chain reaction-restriction fragment length polymorphism method for identification of Toxocara species. In silico analyses using the DNASIS and NEBcutter softwares were performed with rDNA internal transcribed spacers, and mitochondrial cox1 and nad1 sequences obtained in our previous studies along with relevant sequences deposited in GenBank. Consequently, RFLP profiles were designed and all isolates of T. canis and T. cati collected from dogs and cats in different geographical areas of Iran were investigated with the RFLP method using some of the identified suitable enzymes. The findings of in silico analyses predicted that on the cox1 gene only the MboII enzyme is appropriate for PCR-RFLP to reliably distinguish the two species. No suitable enzyme for PCR-RFLP on the nad1 gene was identified that yields the same pattern for all isolates of a species. DNASIS software showed that there are 241 suitable restriction enzymes for the differentiation of T. canis from T. cati based on ITS sequences. RsaI, MvaI and SalI enzymes were selected to evaluate the reliability of the in silico PCR-RFLP. The sizes of restriction fragments obtained by PCR-RFLP of all samples consistently matched the expected RFLP patterns. The ITS sequences are usually conserved and the PCR-RFLP approach targeting the ITS sequence is recommended for the molecular differentiation of Toxocara species and can provide a reliable tool for identification purposes particularly at the larval and egg stages.


PCR-RFLP Toxocara canis Toxocara cati internal transcribed spacers (ITS) identification 


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Copyright information

© Witold Stefański Institute of Parasitology, Polish Academy of Sciences 2017

Authors and Affiliations

  • Fattaneh Mikaeili
    • 1
  • Alexander Mathis
    • 2
  • Peter Deplazes
    • 2
  • Hossein Mirhendi
    • 3
  • Afshin Barazesh
    • 1
  • Sepideh Ebrahimi
    • 1
  • Eshrat Beigom Kia
    • 4
    Email author
  1. 1.Department of Medical Parasitology and Mycology, School of MedicineShiraz University of Medical SciencesShirazIran
  2. 2.Institute of Parasitology, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
  3. 3.Department of Medical Parasitology and Mycology, School of MedicineIsfahan University of Medical SciencesIsfahanIran
  4. 4.Department of Medical Parasitology and Mycology, School of Public HealthTehran University of Medical SciencesTehranIran

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