Evidence map›Paper›PMID 42271343›Full record

ArticleMalaria journal2026

Droplet digital PCR assays for Pvmdr1 and Pvcrt-o gene copy number variation determination in Plasmodium vivax.

Suttipat Srisutham, Kanyarat Boonpeng, Phiraya Pitchayatanakorn, Kaewkanha Kijprasong, Francois H Nosten, Nicholas P J Day, Arjen M Dondorp, Mallika Imwong

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Article in Malaria journal, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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5 · Who and what money

Authors and funding

8 authors.

Suttipat SrisuthamDepartment of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, 10330, Thailand.
Kanyarat BoonpengDepartment of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand.
Phiraya PitchayatanakornDepartment of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, 10330, Thailand.
Kaewkanha KijprasongPhayabalsathanphrabaramee Hospital, Naung Proe, Kanchanaburi, Thailand.
Francois H NostenShoklo Malaria Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand.
Nicholas P J DayMahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Arjen M DondorpMahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Mallika ImwongMahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. mallika.imw@mahidol.ac.th.

Funding

Wellcome Trust
6 · The paper itself

Abstract

backgroundmdr1 and crt-o amplification in Plasmodium vivax has been associated with antimalarial drug resistance and could thus be a molecular marker. Accurate copy number variation (CNV) quantification could provide valuable insights for monitoring resistance trends.

objectivesTo develop a duplex digital PCR (ddPCR) assay for the simultaneous absolute pvmdr1 and pvcrt-o quantification using pvtubulin as a single-copy internal reference.

methodsDuplex ddPCR assays were optimized to target pvmdr1/pvtubulin and pvcrt-o/pvtubulin. CNV was calculated as the ratio of the absolute concentration of the target gene to the reference.

resultsddPCR assays were successfully developed and validated. The quantification limits for assays targeting pvmdr1/pvtubulin and pvcrt-o/pvtubulin, based on pvtubulin concentration, were 22.4 ± 3.5 and 21.5 ± 2.6 copies/µL, respectively. Analysis of field samples from Tak (N = 25) and Kanchanaburi Provinces (N = 97), Thailand, revealed that in 2008, 16% of isolates from Tak carried multiple copies of pvmdr1 and all samples possessed a single copy of pvcrt-o. In contrast, samples collected from the Kanchanaburi Province during 2023-2025 showed no evidence of multiple copies of either gene.

conclusionThis newly developed ddPCR assay provides a robust and highly reproducible tool for monitoring P. vivax drug resistance markers in endemic regions and a potential approach in surveillance programs.

Indexed as

ATP-Binding Cassette, Sub-Family C ProteinsDNA Copy Number VariationsGene DosageMembrane Transport ProteinsPlasmodium vivaxPolymerase Chain ReactionProtozoan ProteinsATP Binding Cassette Transporter, Subfamily BHumansMalaria, VivaxATP-Binding Cassette, Sub-Family C ProteinsATP Binding Cassette Transporter, Subfamily BCrt-o protein, Plasmodium vivaxMdr1 protein, Plasmodium vivaxMembrane Transport ProteinsProtozoan ProteinsCopy number variationDroplet digital PCRPlasmodium vivaxpvcrt-opvmdr1

Identifiers

PMID42271343
PMCPMC13479914

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