Evidence map›Paper›PMID 41943093›Full record

ArticleInternational journal of health geographics2026

Spatial eco-climatic gradients drive adaptive 2La chromosomal inversion polymorphism in Anopheles coluzzii, a major malaria vector in Nigeria.

Adedapo O Adeogun, Oluwakemi Adetunji, Ayodele S Babalola, Romoke T Izekor, Tolulope A Oyeniyi, Oluwaseun Adesoye, Jasini Wahedi, Lateef O Busari, George Aniekeme, Seun Ajayi and 2 more

Abstract read
In one paragraph

Article in International journal of health geographics, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Distinct Genetic Footprint of Adaptation Observed WithinResearch and reports in tropical medicine · 2026
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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors.

Adedapo O Adeogun *Molecular Entomology and Vector Control Unit, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria. dapoadeogun@hotmail.com.
Oluwakemi Adetunji *Molecular Entomology and Vector Control Unit, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria. adesalukemi@gmail.com.
Ayodele S Babalola *Molecular Entomology and Vector Control Unit, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria. ayodelebabalola2011@gmail.com.
Romoke T Izekor *Molecular Entomology and Vector Control Unit, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
Tolulope A OyeniyiMolecular Entomology and Vector Control Unit, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
Oluwaseun AdesoyeDepartment of Biological Sciences, University of Abuja, Abuja, Nigeria.
Jasini WahediDepartment of Zoology, Adamawa State University, Mubi, Adamawa State, Nigeria.
Lateef O BusariDepartment of Biological Sciences, College of Natural and Applied Sciences, Fountain University, Oke-Osun, Osogbo, Osun State, Nigeria.
George AniekemeOxford Vaccine Group, Centre for Clinical Vaccinology and Tropical Medicine, Department of Paediatrics, University of Oxford, Churchill Hospital, Old Road, Headington, Oxford, OX3 7LE, UK.
Seun AjayiCentre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, New Richards Building, Old Road Campus, OX3 7LG, Oxford, UK.
Joseph ChabiVector Research Group, Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra, Ghana.
Samson T AwololaMolecular Entomology and Vector Control Unit, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundChromosomal inversions are important genetic mechanisms that facilitate local adaptation, ecological flexibility, and behavioural variation in mosquito populations. In Anopheles coluzzii, a dominant malaria vector in West Africa, the 2La inversion has been associated with desiccation tolerance, thermal resistance, and insecticide resistance. Despite Nigeria's ecological diversity and substantial malaria burden, the spatial distribution and clinal dynamics of 2La inversion polymorphism in An. coluzzii remain poorly characterized. This study investigated the distribution of 2La inversion karyotypes across major Nigerian ecozones and examined their association with climatic gradients.

methodsLarvae of Anopheles mosquitoes were sampled across 12 states representing Nigeria's southern, central, and northern ecological zones. Species identification was conducted morphologically and confirmed with PCR diagnostics. The 2La inversion was determined using established molecular assays, and allele frequencies were analyzed with respect to ecozone and climatic gradients. Spatial distribution maps and statistical analyses, including correlation and clinal trend assessment, were done in R version 4.4.

resultsA clear geographic structuring of 2La inversion polymorphism was observed in An. coluzzii populations. The 2La/2La homokaryotype was strongly predominant in the northern Sahelian and Sudan savanna ecozones, reflecting adaptation to hot and arid conditions. In contrast, the standard 2La+/2La+ arrangement was predominant in humid southern forest and mangrove regions. The heterokaryotype (2La/2La+) occurred at intermediate frequencies within the central transitional belt, where ecological gradients overlap. Karyotype frequencies exhibited a pronounced latitudinal cline, with heterozygosity peaking in central Nigeria. The spatial patterns indicate that climatic pressures, particularly aridity and humidity, might be a major determinant of inversion distribution in An. coluzzii from Nigeria.

conclusionThis study provides the first detailed nationwide characterization of 2La inversion polymorphism in An. coluzzii across Nigeria's ecological zones. The strong alignment between inversion frequency and eco-climatic gradients highlights the role of chromosomal rearrangements in promoting vector survival and ecological fitness. These adaptive patterns have significant implications for malaria control, as inversion-mediated adaptability may influence resting behaviour, insecticide response, and vector persistence under climate change. Integrating chromosomal inversion surveillance into entomological monitoring frameworks will be essential for designing ecologically tailored vector control strategies in Nigeria.

Indexed as

AnophelesChromosome InversionClimateMalariaMosquito VectorsPolymorphism, GeneticAnimalsEcosystemNigeria2La chromosomal inversionAn. coluzziiClimatic gradientsEcological adaptationMalaria vectorNigeria

Identifiers

PMID41943093
PMCPMC13220388

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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 OpenQuestion graph.