Volume 78, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Standard polymerase chain reaction methods often cannot detect drug-resistance mutations in infections if the mutation is present in ≤ 20% of the parasites. A heteroduplex tracking assay was developed that can detect dihydrofolate reductase 164-L mutations in variants representing 1% of the parasites in an individual host. Using this assay, we confirmed the presence of the mutation in infections in Malawi.


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  • Received : 13 Dec 2007
  • Accepted : 17 Mar 2008

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