An ace-1 gene duplication resorbs the fitness cost associated with resistance in Anopheles gambiae, the main malaria mosquito.

Assogba BS, Djogbénou LS, Milesi P, Berthomieu A, Perez J, Ayala D, Chandre F, Makoutodé M, Labbé P, Weill M

Sci Rep 5 (-) 14529 [2015-10-05; online 2015-10-05]

Widespread resistance to pyrethroids threatens malaria control in Africa. Consequently, several countries switched to carbamates and organophophates insecticides for indoor residual spraying. However, a mutation in the ace-1 gene conferring resistance to these compounds (ace-1(R) allele), is already present. Furthermore, a duplicated allele (ace-1(D)) recently appeared; characterizing its selective advantage is mandatory to evaluate the threat. Our data revealed that a unique duplication event, pairing a susceptible and a resistant copy of the ace-1 gene spread through West Africa. Further investigations revealed that, while ace-1(D) confers less resistance than ace-1(R), the high fitness cost associated with ace-1(R) is almost completely suppressed by the duplication for all traits studied. ace-1 duplication thus represents a permanent heterozygote phenotype, selected, and thus spreading, due to the mosaic nature of mosquito control. It provides malaria mosquito with a new evolutionary path that could hamper resistance management.

Pascal Milesi

SciLifeLab Fellow

PubMed 26434951

DOI 10.1038/srep14529

Crossref 10.1038/srep14529

pii: srep14529
pmc: PMC4592963

Publications 9.5.0