ArticleMalaria journal2018
Genetic polymorphisms in the circumsporozoite protein of Plasmodium malariae show a geographical bias.
Article in Malaria journal, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers.
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10 citing papers in PubMed, 19 citations in OpenAlex.
- Genetic polymorphism and natural selection of apical membrane antigen-1 in Plasmodium malariae isolated from Vietnam.BMC infectious diseases · 2026Article
- Unraveling the origins and features of long-latency Plasmodium malariae infections: a comprehensive epidemiological, clinical, and genetic study of seven cases in Guangdong Province (2014-2022).BMC infectious diseases · 2026Article
- The primate malaria parasites Plasmodium malariae, Plasmodium brasilianum and Plasmodium ovale spp.: genomic insights into distribution, dispersal and host transitions.Malaria journal · 2022Review
- Analysis of nucleic acids extracted from rapid diagnostic tests reveals a significant proportion of false positive test results associated with recent malaria treatment.Malaria journal · 2022Article
- Selective whole genome amplification of Plasmodium malariae DNA from clinical samples reveals insights into population structure.Scientific reports · 2020Article
- Polymorphic markers for identification of parasite population in Plasmodium malariae.Malaria journal · 2020Article
- Article
- Genome-wide microsatellite characteristics of five human Plasmodium species, focusing on Plasmodium malariae and P. ovale curtisi.Parasite (Paris, France) · 2020Article
- Article
- Genetic dissociation of three antigenic genes in Plasmodium ovale curtisi and Plasmodium ovale wallikeri.PloS one · 2019Article
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11 authors at 6 institutions in 4 countries.
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Abstract
backgroundPlasmodium malariae is characterized by its long asymptomatic persistence in the human host. The epidemiology of P. malariae is incompletely understood and is hampered by the limited knowledge of genetic polymorphisms. Previous reports from Africa have shown heterogeneity within the P. malariae circumsporozoite protein (pmcsp) gene. However, comparative studies from Asian countries are lacking. Here, the genetic polymorphisms in pmcsp of Asian isolates have been characterized.
methodsBlood samples from 89 symptomatic P. malariae-infected patients were collected, from Thailand (n = 43), Myanmar (n = 40), Lao PDR (n = 5), and Bangladesh (n = 1). pmcsp was amplified using semi-nested PCR before sequencing. The resulting 89 pmcsp sequences were analysed together with 58 previously published pmcsp sequences representing African countries using BioEdit, MEGA6, and DnaSP.
resultsPolymorphisms identified in pmcsp were grouped into 3 populations: Thailand, Myanmar, and Kenya. The nucleotide diversity and the ratio of nonsynonymous to synonymous substitutions (dN/dS) in Thailand and Myanmar were higher compared with that in Kenya. Phylogenetic analysis showed clustering of pmcsp sequences according to the origin of isolates (Asia vs. Africa). High genetic differentiation (Fst = 0.404) was observed between P. malariae isolates from Asian and African countries. Sequence analysis of pmcsp showed the presence of tetrapeptide repeat units of NAAG, NDAG, and NAPG in the central repeat region of the gene. Plasmodium malariae isolates from Asian countries carried fewer copies of NAAG compared with that from African countries. The NAPG repeat was only observed in Asian isolates. Additional analysis of 2 T-cell epitopes, Th2R and Th3R, showed limited heterogeneity in P. malariae populations.
conclusionsThis study provides valuable information on the genetic polymorphisms in pmcsp isolates from Asia and advances our understanding of P. malariae population in Asia and Africa. Polymorphisms in the central repeat region of pmcsp showed association with the geographical origin of P. malariae isolates and can be potentially used as a marker for genetic epidemiology of P. malariae population.
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