PMID: 9550212Apr 29, 1998Paper

Development and comparison of quantitative assays for the dihydropteroate synthetase codon 540 mutation associated with sulfadoxine resistance in Plasmodium falciparum

Parasitology
M F ShaioJ E Hyde

Abstract

A point mutation in codon 540 of the dihydropteroate synthetase (dhps) gene affecting sulfadoxine resistance has previously been found in parasites from patients with Plasmodium falciparum infection. Here, we investigated 4 methods of identifying this mutation in clinical specimens and established a reliable quantitative assay to estimate the percentage of resistant type in mixed infections. A diagnostic PCR assay based on allele-specific amplification was developed, which clearly typed the clinical specimens examined. The mutation in codon 540 introduces an additional FokI cleavage site which provided a second method to differentiate mutant from wild type, where the former gives rise to 2 characteristic fragments of 538 and 326 bp that are absent from the latter. To calibrate quantitatively the ratio of alleles in mixed samples, we constructed artificial mixes containing 2 plasmid DNAs, one carrying the mutation and the other a wild-type insert. When 32P-labelling was employed, the allele-specific PCR assay could detect the level of resistant type in a mixture down to 0.1-1%, while for the restriction enzyme/PCR analysis, the figure was approximately 10%. Furthermore, neither fluorescent dye-labelled terminator nor dye-labelle...Continue Reading

Citations

Dec 12, 2002·Transactions of the Royal Society of Tropical Medicine and Hygiene·L C Ranford-CartwrightH A Babiker
Jun 12, 2002·Biological Reviews of the Cambridge Philosophical Society·T Pizzari, T R Birkhead
Jan 21, 2003·Emerging Infectious Diseases·Annie-Claude LabbéKevin C Kain
Feb 13, 2007·Travel Medicine and Infectious Disease·M Haditsch
Aug 3, 2005·Molecular and Biochemical Parasitology·Paul HuntDavid Walliker
Nov 10, 2006·Drug Resistance Updates : Reviews and Commentaries in Antimicrobial and Anticancer Chemotherapy·C V PloweO K Doumbo
Mar 1, 2005·Pharmacological Reviews·Aric Gregson, Christopher V Plowe

❮ Previous
Next ❯

Related Concepts

Related Feeds

Antimalarial Agents (ASM)

Antimalarial agents, also known as antimalarials, are designed to prevent or cure malaria. Discover the latest research on antimalarial agents here.

Antimalarial Agents

Antimalarial agents, also known as antimalarials, are designed to prevent or cure malaria. Discover the latest research on antimalarial agents here.