Partial Sequence Analysis of Merozoite Surface Proteine-3 alpha Gene in Plasmodium vivax Isolates from Malarious Areas of Iran

Abstract

Background: Approximately 85-90% of malaria infections in Iran are attributed to Plasmodium vivax, while little is known about the genetic of the parasite and its strain types in this region. This study was designed and performed for describing genetic characteristics of Plasmodium vivax population of Iran based on the merozoite surface protein-3 alpha gene sequence. Methods: Through a descriptive study we analyzed partial P. vivax merozoite surface protein-3 alpha gene sequences from 17 clinical P. vivax isolates collected from malarious areas of Iran. Genomic DNA was extracted by Q1Aamp (R) DNA blood mini kit, amplified through nested PCR for a partial nucleotide sequence of PvMSP-3 alpha. gene in P. vivax. PCR-amplified products were sequenced with an ABI Prism Perkin-Elmer 310 sequencer machine and the data were analyzed with clustal W software. Results: Analysis of PvMSP-3a gene sequences demonstrated extensive polymorphisms, but the sequence identity between isolates of same types was relatively high. We identified specific insertions and deletions for the types A. B and C variants of P. vivax in our isolates. In phylogenetic comparison of geographically separated isolates. there was not a significant geographical branching of the parasite Populations. Conclusion: The highly polymorphic nature of isolates suggests that more investigations of the PvMSP-3 alpha gene are needed to explore its vaccine potential.