{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T23:26:45Z","timestamp":1783553205792,"version":"3.55.0"},"reference-count":46,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,4,1]],"date-time":"2022-04-01T00:00:00Z","timestamp":1648771200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100004440","name":"Wellcome Trust","doi-asserted-by":"publisher","award":["217188\/Z\/19\/Z"],"award-info":[{"award-number":["217188\/Z\/19\/Z"]}],"id":[{"id":"10.13039\/100004440","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Metabolic-based resistance to insecticides limit the control of medically important pests, and it is extremely detrimental in the ongoing struggle to control disease vectors. Elucidating the fitness cost of metabolic resistance in major malaria vectors is vital for successful resistance management. We established the fitness cost of the 6.5kb structural variant (6.5kb-sv) between the duplicated CYP6P9a\/b P450s using the hybrid strain generated from the crossing between two An. funestus laboratory strains. Furthermore, we assessed the cumulative impact of this marker with the duplicated P450 genes. We established that individuals that were homozygote for the resistant structural variant (SV) presented reduced fecundity and slow development relative to those that were homozygote for the susceptible SV. Furthermore, we observed that 6.5kb act additively with CYP6P9a and CYP6P9b to exacerbate the reduced fecundity and the increased development time of resistant mosquitoes since double\/triple homozygote susceptible (SS\/SS\/SS) significantly laid more eggs and developed faster than other genotypes. Moreover, a restoration of susceptibility was noted over 10 generations in the insecticide-free environment with an increased proportion of susceptible individuals. This study highlights the negative impact of multiple P450-based resistance on the key physiological traits of malaria vectors. Such high fitness costs suggest that in the absence of selection pressure, the resistant individuals will be outcompeted in the field. Therefore, this should encourage future strategies based on the rotation of insecticides to reduce selection pressure and to slow the spread of pyrethroid resistance.<\/jats:p>","DOI":"10.3390\/genes13040626","type":"journal-article","created":{"date-parts":[[2022,4,1]],"date-time":"2022-04-01T21:22:39Z","timestamp":1648848159000},"page":"626","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["A 6.5kb Intergenic Structural Variation Exacerbates the Fitness Cost of P450-Based Metabolic Resistance in the Major African Malaria Vector Anopheles funestus"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1683-8057","authenticated-orcid":false,"given":"Magellan","family":"Tchouakui","sequence":"first","affiliation":[{"name":"Centre for Research in Infectious Diseases, Yaound\u00e9 P.O. Box 13591, Cameroon"},{"name":"Parasitology and Ecology Laboratory, Department of Animal Biology and Physiology, Faculty of Science, University of Yaound\u00e9 1, Yaound\u00e9 P.O. Box 812, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leon M. J.","family":"Mugenzi","sequence":"additional","affiliation":[{"name":"Centre for Research in Infectious Diseases, Yaound\u00e9 P.O. Box 13591, Cameroon"},{"name":"Department of Biochemistry and Molecular Biology, Faculty of Science University of Buea, Buea P.O. Box 63, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Murielle J.","family":"Wondji","sequence":"additional","affiliation":[{"name":"Centre for Research in Infectious Diseases, Yaound\u00e9 P.O. Box 13591, Cameroon"},{"name":"Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Micareme","family":"Tchoupo","sequence":"additional","affiliation":[{"name":"Centre for Research in Infectious Diseases, Yaound\u00e9 P.O. Box 13591, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Flobert","family":"Njiokou","sequence":"additional","affiliation":[{"name":"Parasitology and Ecology Laboratory, Department of Animal Biology and Physiology, Faculty of Science, University of Yaound\u00e9 1, Yaound\u00e9 P.O. Box 812, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0791-3673","authenticated-orcid":false,"given":"Charles S.","family":"Wondji","sequence":"additional","affiliation":[{"name":"Centre for Research in Infectious Diseases, Yaound\u00e9 P.O. Box 13591, Cameroon"},{"name":"Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,1]]},"reference":[{"key":"ref_1","unstructured":"WHO (2019). World Malaria Report 2019, WHO."},{"key":"ref_2","unstructured":"WHO (2012). Global Plan for Insecticide Resistance Management (GPIRM), World Health Organization. Global Malaria Programme."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1038\/nature15535","article-title":"The effect of malaria control on Plasmodium falciparum in Africa between 2000 and 2015","volume":"526","author":"Bhatt","year":"2015","journal-title":"Nature"},{"key":"ref_4","unstructured":"WHO (2016). 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