title: Molecular analysis of reticulocyte binding protein-2 gene in Plasmodium vivax isolates from India.
abstract: BACKGROUND
  Plasmodium vivax reticulocyte binding protein-2 (PvRBP-2) is a promising candidate for development of vaccine against parasite. DNA sequence polymorphism in pvrbp-2 which may hamper the vaccine development program has been identified in laboratory strains. Therefore, unraveling genetic polymorphism in pvrbp-2 from field isolates is a prerequisite for success in vaccine development. This study was designed with a primary aim to uncover genetic polymorphism in pvrbp-2 among P. vivax field isolates.
  
  
  RESULTS
  Using virtual restriction mapping of pvrbp-2 sequences, two restriction enzymes (AluI and ApoI) were selected for the development of pvrbp-2 as a PCR-RFLP marker. Restriction fragment length polymorphism (RFLP) analysis revealed a high degree of genetic polymorphism in the pvrbp-2 gene among field isolates of P. vivax. ApoI-RFLP was found to be more efficient in identifying the extent of genetic polymorphism in pvrbp-2 compared to AluI-RFLP. Combined genotyping/haplotyping of RFLP pattern revealed a total of 36 distinct RFLP patterns among 83 P. vivax isolates analyzed. DNA sequence analysis also supports high degree of genetic polymorphism among field isolates of P. vivax. Pvrbp-2 PCR-RFLP method is able to distinguish multiple infection up to 16.86% and it revealed a low level of shared genetic pool between more than two populations.
  
  
  CONCLUSIONS
  The study suggests that pvrbp-2 is highly polymorphic genetic marker which can be used for population genetic analyses. RFLP analysis suggests presence of nearly similar proportion of Sal-1 and Belem alleles in Indian P. vivax populations. The larger extent of genetic polymorphism identified from limited samples advocates to screen genetic polymorphism in pvrbp-2 from malaria endemic geographical regions and countries for designing pvrbp-2 based anti-malarial control measures.
authors.affiliation: Molecular Biology Division, National Institute of Malaria Research, Sector 8, Dwarka, Delhi, India. surendramrc@gmail.com
authors.forename: Surendra K
authors.initials: SK
authors.lastname: Prajapati
authors.forename: Pragati
authors.initials: P
authors.lastname: Kumari
authors.forename: Om P
authors.initials: OP
authors.lastname: Singh
mesh_terms: D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D005838:Genotype; D006801:Humans; D007194:India; D016780:Malaria, Vivax / Q000469:parasitology*; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D010966:Plasmodium vivax / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D015800:Protozoan Proteins / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D016054:DNA, Protozoan; D008565:Membrane Proteins; D015800:Protozoan Proteins; C075483:reticulocyte-binding protein, Plasmodium vivax