Evidence map›Paper›PMID 41987254›Full record

ArticleMalaria journal2026

G6PD variants but not Filipino beta-thalassemia are associated with reduced risk of Plasmodium knowlesi infection in Sabah, Malaysia.

Nor Afizah Nuin, Giri S Rajahram, Bridget E Barber, Nicholas M Anstey, Matthew J Grigg, Tock H Chua

Abstract read
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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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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Nor Afizah NuinDepartment of Pathology and Microbiology, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Malaysia.
Giri S RajahramDepartment of Medicine, Queen Elizabeth Hospital II, Ministry of Health Malaysia, 88300, Kota Kinabalu, Malaysia.
Bridget E BarberInfectious Diseases Society Kota Kinabalu Sabah-Clinical Research Unit, 88560, Kota Kinabalu, Malaysia.
Nicholas M AnsteyInfectious Diseases Society Kota Kinabalu Sabah-Clinical Research Unit, 88560, Kota Kinabalu, Malaysia.
Matthew J Grigg *Infectious Diseases Society Kota Kinabalu Sabah-Clinical Research Unit, 88560, Kota Kinabalu, Malaysia.
Tock H Chua *Edulife Bhd, C/O Pacos, Penampang, 89507, Kota Kinabalu, Sabah, Malaysia. chuath@gmail.com.

Funding

Ministry of Health, Malaysia BP00500420 and BP00500/117/1002US National Institutes of Health 1R01AI160457-01
6 · The paper itself

Abstract

backgroundThe emergence of Plasmodium knowlesi as the predominant cause of malaria in Malaysian Borneo raises important questions about protective genetic factors in endemic populations. This study investigates two common erythrocyte polymorphisms, glucose-6-phosphate dehydrogenase (G6PD) deficiency and Filipino β-thalassemia, for association with P. knowlesi infection risk.

methodsA retrospective case-control study compared 106 PCR-confirmed P. knowlesi cases with 89 controls from Sabah, Malaysia. Genotyping used multiplex PCR (8 major Southeast Asian G6PD variants) and gap-PCR (Filipino β-thalassemia deletions). Statistical analysis employed Fisher's exact tests and logistic regression models to evaluate associations with infection risk, including controlling for age, sex, ethnicity and district site.

resultsG6PD deficiency genetic variants were present in 4/106 (3.8%, 95%CI 1.0-9.4%) P. knowlesi cases compared to 11/89 (12.4%, 95%CI 6.3-21.0%) controls (OR = 0.28, 95%CI 0.09-0.91; p = 0.034). The Viangchan variant (871G>A) was predominant (71%), with Coimbra and Mediterranean variants also present. No relationship with G6PD variants and severe malaria or sex was detected, although analysis was constrained by small numbers. Filipino β-thalassemia demonstrated no association.

conclusionsG6PD deficiency related variants confer substantial protection against P. knowlesi susceptibility, while β-thalassemia appears neutral. Findings have implications for zoonotic malaria transmission risk in Southeast Asia.

Indexed as

beta-ThalassemiaGlucosephosphate DehydrogenaseGlucosephosphate Dehydrogenase DeficiencyMalariaPlasmodium knowlesiPolymorphism, GeneticAdolescentAdultCase-Control StudiesChildFemaleHumansMalaysiaMaleRetrospective StudiesYoung AdultG6PD protein, humanGlucosephosphate DehydrogenaseG6PD deficiencyHost geneticsMalaysiaPlasmodium knowlesiZoonotic malariaβ-thalassemia

Identifiers

PMID41987254
PMCPMC13202753

What Socratic holds

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LicenceCC BY-NC-ND
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.