A new method for detection of pfmdr1 mutations in Plasmodium falciparum DNA using real-time PCR
Anne Purfield1, Amy Nelson, Anita Laoboonchai
1Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC, USA. purfield@med.unc.edu
Background:
Surveillance for drug-resistant Plasmodium falciparum should be a component of malaria control programmes. Real-time PCR methods for the detection of parasite single-nucleotide polymorphisms (SNPs) and gene amplification could be useful survellance tools.
Methods:
A real-time PCR assay has been developed that identifies single nucleotide polymorphisms (SNPs) at amino acids 86, 184, 1034 and 1042 in the P. falciparum multi-drug resistant (pfmdr 1) gene that may be associated with anti-malarial drug resistance.
Results:
This assay has a sensitivity and specificity of 94% and 100% when compared to traditional PCR methods for genotyping. Only 54 of 68 (79%) paired pre- and post-culture DNA samples were concordant at all four loci.
Conclusion:
Real-time PCR is a sensitive and specific method to detect SNP's in pfmdr 1. Genotypes of parasites after in vitro culture may not reflect that seen in vivo.
