Novel dhps and pfcrt polymorphisms in Plasmodium falciparum detected by heteroduplex tracking assay.
Several single nucleotide polymorphisms (SNPs) have been linked to antimalarial drug resistance in Plasmodium falciparum. However, standard polymerase chain reaction (PCR) methods to detect these polymorphisms are unable to detect SNPs in variants representing < 20% of the parasites in a mixed infection, nor can they detect polymorphisms at nearby loci. Here we use heteroduplex tracking assays (HTAs) to analyze dhps540 mutations in 96 samples from Peru and pfcrt76 mutations in 70 samples from China. All samples had been previously analyzed by standard PCR. We detected drug-resistant minority variants and two novel non-synonymous pfcrt mutations in China. In Peru, we found no drug-resistant minority variants and a synonymous mutation in dhps. Thus, even in regions of low malaria transmission, HTA assays are more informative than PCR with agarose gel electrophoresis.
Juliano
Jonathan J
JJ
Division of Infectious Diseases, University of North Carolina, School of Medicine, Chapel Hill, North Carolina 27599-7300, USA. jjuliano@med.unc.edu
Bacon
David J
DJ
Mu
Jianbing
J
Wang
Xinhua
X
Meshnick
Steven R
SR
D000595:Amino Acid Sequence; D000818:Animals; D004094:Dihydropteroate Synthase / Q000235:genetics*; D004351:Drug Resistance / Q000235:genetics; D020180:Heteroduplex Analysis; D006801:Humans; D016778:Malaria, Falciparum / Q000469:parasitology; D026901:Membrane Transport Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000187:drug effects / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D015800:Protozoan Proteins / Q000235:genetics*; D012680:Sensitivity and Specificity
D026901:Membrane Transport Proteins; C416369:PfCRT protein, Plasmodium falciparum; D015800:Protozoan Proteins; D004094:Dihydropteroate Synthase