Photo Credit: Rapha Wilde
Scientific Frontline: Extended "At a Glance" Summary: Malaria Drug Resistance and Genetic Mutations
The Core Concept: Researchers have identified a new set of rapidly spreading genetic variants in malaria parasites that significantly reduce their susceptibility to the most common front-line antimalarial treatments.
Key Distinction/Mechanism: Unlike previously identified mutations that offered partial resistance to a single drug (artemisinin), this newly discovered linked variant set (involving the PX1 gene) is associated with decreased susceptibility to multiple drugs simultaneously, including both components of the standard combination therapy (artemether and lumefantrine) as well as mefloquine.
Major Frameworks/Components:
- Whole-Genome Sequencing: Used to discover exact genetic determinants of drug resistance shifts across the entire parasite genome, moving beyond tracking known markers.
- PX1 Gene Mutation: A linked variant set comprising three specific mutations and two deletions in the gene encoding the phosphoinositide-binding protein (PX1) is identified as the likely driver of this multi-drug resistance.
- Artemisinin-Based Combination Therapy (ACT): The standard treatment (specifically artemether-lumefantrine, or AL) whose efficacy is being undermined by these mutations.
- Genomic Surveillance: The integration of these newly identified molecular markers into surveillance systems to track the spread of resistance and inform public health strategies.
Branch of Science: Genetics, Genomics, Parasitology, Pharmacology, Epidemiology, Infectious Diseases, and Public Health.
Future Application: These findings will directly inform the development of prediction models to forecast when current antimalarial drugs will completely fail, guide the integration of this new molecular marker into widespread genomic surveillance systems across Africa, and highlight the urgent necessity for developing entirely novel antimalarial therapies.
Why It Matters: Malaria remains a leading cause of death globally, especially in sub-Saharan Africa. The rapid spread of multi-drug resistant parasites threatens to severely undermine current control efforts, potentially leading to a massive resurgence in malaria-related mortality if new treatments and precise tracking systems are not deployed.
Researchers searching for genetic clues to the growing problem of malaria drug resistance have identified new mutations associated with the parasite’s decreased susceptibility to current treatments.
By sequencing the whole genomes of malaria parasites from the blood of hundreds of infected people in Uganda, a team of researchers led by scientists at Brown University found that a cluster of genetic variants in some parasites showed significantly decreased susceptibility to the drugs most commonly used to treat malaria in Africa and the United States.
“It’s very concerning that these new mutations are spreading so rapidly—it tells us they are important to the parasite’s survival,” said study author Jeffrey Bailey, an associate professor of translational research and of pathology and laboratory medicine at Brown University. “Malaria still is a major killer, particularly in sub-Saharan Africa. As drug resistance continues to emerge, we worry it will undermine control of its spread and result in even more deaths for a large number of people there and beyond.”
Drug resistance often happens when treatments for bacterial, viral, or parasitic illnesses are offered on a very large scale, as is the case with malaria treatment in Africa. Because of that, Bailey explained, surveillance systems are being built to track known mutations in the pathogen as well as drug performance over time.
Bailey’s lab at Brown has been instrumental in building genomics systems to support the surveillance programs by sequencing DNA and tracking mutations, and it has received federal and foundation grants for this work in countries across Africa.
The surveillance projects tend to focus on identified biological markers of drug resistance, Bailey said. To discover clues to explain new susceptibility patterns, Karamoko Niaré, formerly a postdoctoral researcher in Bailey’s lab, started to focus on whole-genome sequencing.
“We knew that the parasites were changing so that over time, their susceptibility to malaria treatments was decreasing, and we wanted to know the exact genetic determinants of this shift,” said Niaré, now an adjunct assistant professor of pathology and laboratory medicine at Brown and the first author of the publication. “We decided to sequence the entire genome to get a better sense of what was going on.”
A Molecular Marker to Track Drug Resistance
For the past two decades or so, the primary treatment for uncomplicated malaria in Uganda has been artemether-lumefantrine (AL), the most widely used artemisinin-based combination therapy (ACT) across sub-Saharan Africa. As of 2026, the Centers for Disease Control and Prevention has been recommending a longer course of therapy because standard doses failed to cure several travelers returning home, suggesting that the parasites are becoming less susceptible to treatment.
The researchers identified an area in the genome of the malaria parasite encompassing sixty-nine genes. Through additional genetic analyses, they found that a linked variant set comprising three specific mutations and two deletions was associated with decreased susceptibility to the drugs artemisinin and lumefantrine (both components of AL), as well as the malaria drug mefloquine. The mutations most likely to drive this selection were found in a gene that encodes a protein called PX1, or phosphoinositide-binding protein, which is often found near another gene product known to cause moderate resistance to the drug artemisinin.
This is the first time researchers have correlated a gene mutation with reduced susceptibility to multiple drugs used in combination therapies for malaria.
“We didn’t have any validated molecular marker of lumefantrine resistance—we knew that there was a gene involved in partial resistance to artemisinin but couldn’t explain changes observed for lumefantrine,” Niaré said. “Our work identifies a molecular marker that could be used by surveillance studies to track the emergence and spread of reduced susceptibility to frontline malaria treatments across Africa. That’s a very important tool for public health.”
The newly discovered mutation should be integrated into mutation-tracking systems and further studied, Niaré said.
Because this effect was studied in the lab using parasites collected from malaria patients, Bailey said, future research should investigate how these mutant parasites impact the clinical outcomes of malaria treatment with ACTs. Although the authors found that the mutation was spreading rapidly in Uganda, how far it has spread beyond Uganda’s borders remains unknown and must be examined.
The finding has major implications for sustaining an effective malaria-treatment program, Bailey said.
“It underscores the need to develop prediction models for when the drug will stop working altogether,” Bailey said, “and also highlights the urgency to develop new drugs to treat malaria.”
Melissa Conrad, an associate professor at Johns Hopkins University, supervised the work jointly with Bailey. The project was a collaboration featuring integral work from other investigators at the Infectious Disease Research Collaboration in Uganda; the University of California, San Francisco; the University of North Carolina at Chapel Hill; and the University of Notre Dame.
Funding: The study was funded by the National Institutes of Health/National Institute of Allergy and Infectious Diseases (R01AI173557, K24AI134990, R01AI075045, U19AI089674, R01AI117001, and R01AI139179); the Medicines for Malaria Venture (RD/15/0001); and the Gates Foundation (INV-035751).
Published in journal: Nature Medicine
Authors: Karamoko Niaré, Bersabeh Tafesse, Mayland Treat, Jacob M. Sadler, Martin Okitwi, Stephen Orena, Victor Asua, Oriana Kreutzfeld, Jenny Legac, Jacob Marglous, Samuel L. Nsobya, Adoke Yeka, Dave Richard, Michael T. Ferdig, Angana Mukherjee, Philip J. Rosenthal, Jonathan J. Juliano, Jeffrey A. Bailey, and Melissa D. Conrad
Source/Credit: Brown University
Edited by: Scientific Frontline
Reference Number: gen081726_01
