title: Deltamethrin Resistance Mechanisms in Aedes aegypti Populations from Three French Overseas Territories Worldwide.
abstract: BACKGROUND
  Aedes aegypti is a cosmopolite mosquito, vector of arboviruses. The worldwide studies of its insecticide resistance have demonstrated a strong loss of susceptibility to pyrethroids, the major class of insecticide used for vector control. French overseas territories such as French Guiana (South America), Guadeloupe islands (Lesser Antilles) as well as New Caledonia (Pacific Ocean), have encountered such resistance.
  
  
  RESULTS
  We initiated a research program on the pyrethroid resistance in French Guiana, Guadeloupe and New Caledonia. Aedes aegypti populations were tested for their deltamethrin resistance level then screened by an improved microarray developed to specifically study metabolic resistance mechanisms. Cytochrome P450 genes were implicated in conferring resistance. CYP6BB2, CYP6M11, CYP6N12, CYP9J9, CYP9J10 and CCE3 genes were upregulated in the resistant populations and were common to other populations at a regional scale. The implication of these genes in resistance phenomenon is therefore strongly suggested. Other genes from detoxification pathways were also differentially regulated. Screening for target site mutations on the voltage-gated sodium channel gene demonstrated the presence of I1016 and C1534.
  This study highlighted the presence of a common set of differentially up-regulated detoxifying genes, mainly cytochrome P450 genes in all three populations. GUA and GUY populations shared a higher number of those genes compared to CAL. Two kdr mutations well known to be associated to pyrethroid resistance were also detected in those two populations but not in CAL. Different selective pressures and genetic backgrounds can explain such differences. These results are also compared with those obtained from other parts of the world and are discussed in the context of integrative research on vector competence.
authors.affiliation: Institut Pasteur de la Guyane, Unité d'Entomologie Médicale, Cayenne, French Guiana, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Dusfour
authors.affiliation: Unidad de Biología Molecular, Institut Pasteur de Montevideo and Dept. of Biochemistry, School of Medicina, Montevideo, Uruguay.
authors.forename: Pilar
authors.initials: P
authors.lastname: Zorrilla
authors.affiliation: Institut Pasteur de la Guyane, Unité d'Entomologie Médicale, Cayenne, French Guiana, France.
authors.forename: Amandine
authors.initials: A
authors.lastname: Guidez
authors.affiliation: Institut Pasteur de la Guyane, Unité d'Entomologie Médicale, Cayenne, French Guiana, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Issaly
authors.affiliation: Institut Pasteur de la Guyane, Unité d'Entomologie Médicale, Cayenne, French Guiana, France.
authors.forename: Romain
authors.initials: R
authors.lastname: Girod
authors.affiliation: Institut Pasteur de Nouvelle Calédonie, Unité de Recherche et d'Expertise en Entomologie Médicale, Noumea, New Caledonia.
authors.forename: Laurent
authors.initials: L
authors.lastname: Guillaumot
authors.affiliation: Unidad de Biología Molecular, Institut Pasteur de Montevideo and Dept. of Biochemistry, School of Medicina, Montevideo, Uruguay.
authors.forename: Carlos
authors.initials: C
authors.lastname: Robello
authors.affiliation: Biology Department, Edge Hill University, Ormskirk, Lancashire, United Kingdom.
authors.forename: Clare
authors.initials: C
authors.lastname: Strode
mesh_terms: D000330:Aedes / Q000187:drug effects* / Q000235:genetics; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics; D005260:Female; D005616:French Guiana; D020869:Gene Expression Profiling; D019430:Guadeloupe; D007305:Insecticide Resistance; D007306:Insecticides / Q000494:pharmacology*; D046228:Microarray Analysis; D050505:Mutant Proteins / Q000235:genetics; D009510:New Caledonia; D009570:Nitriles / Q000494:pharmacology*; D011722:Pyrethrins / Q000494:pharmacology*; D061566:Voltage-Gated Sodium Channels / Q000235:genetics
chemical_list: D007306:Insecticides; D050505:Mutant Proteins; D009570:Nitriles; D011722:Pyrethrins; D061566:Voltage-Gated Sodium Channels; C017180:decamethrin; D003577:Cytochrome P-450 Enzyme System