Measuring allelic heterogeneity in Plasmodium falciparum by a heteroduplex tracking assay
Ngrenngarmlert, W.; Kwiek, J.J.; Kamwendo, D.D.; Ritola, K.; Swanstrom, R.; Wongsrichanalai, C.; Miller, R.Scott.; Ittarat, W.; Meshnick, S.R.
American Journal of Tropical Medicine and Hygiene 72(6): 694-701
2005
ISSN/ISBN: 0002-9637 PMID: 15964952 Document Number: 593144
We developed a novel Plasmodium falciparum genotyping strategy based on the heteroduplex tracking assay (HTA) method commonly used to genotype viruses. Because it can detect both sequence and size polymorphisms, we hypothesized that HTA is more sensitive than current methods. To test this hypothesis, we compared the ability of HTA and a nested polymerase chain reaction (PCR) to detect genetic diversity in 17 Thai samples. The HTA detected more MSPI sequence variants in eight isolates (47%), less sequence variants in three isolates (18%), and an equal number of sequence variants in six isolates (35%), suggesting that HTA is equal to or more sensitive than the nested PCR. This study is a proof of concept that HTA is a sensitive allelic discrimination method able to determine genetic diversity in P. falciparum and warrants its use in studies of antimalarial drug efficacy.