@article{fdi:010062540,
  title = {{M}olecular characterization of {DDT} resistance in {A}nopheles gambiae from {B}enin},
  author = {{D}jegbe, {I}. and {A}gossa, {F}. {R}. and {J}ones, {C}. {M}. and {P}oupardin, {R}. and {C}orn{\'e}lie, {S}ylvie and {A}kogbeto, {M}. and {R}anson, {H}. and {C}orbel, {V}incent},
  editor = {},
  language = {{ENG}},
  abstract = {{B}ackground: {I}nsecticide resistance in the mosquito vector is the one of the main obstacles against effective malaria control. {I}n order to implement insecticide resistance management strategies, it is important to understand the genetic factors involved. {I}n this context, we investigated the molecular basis of {DDT} resistance in the main malaria vector from {B}enin. {M}ethods: {A}nopheles gambiae mosquitoes were collected from four sites across {B}enin and identified to species/molecular form. {M}osquitoes from {C}otonou ({M}-form), {T}ori-{B}ossito ({S}-form) and {B}ohicon ({S}-form) were exposed to {DDT} 4% at a range of exposure times (30 min to 300 min). {A}nother batch of mosquitoes from {C}otonou and {M}alanville were exposed to {DDT} for 1 hour and the survivors 48 hours post exposure were used to quantify metabolic gene expression. {Q}uantitative {PCR} assays were used to quantify m{RNA} levels of metabolic enzymes: {GSTE}2, {GSTD}3, {CYP}6{P}3 and {CYP}6{M}2. {E}xpression (fold-change) was calculated using the {D}elta {D}elta {C}t method and compared to susceptible strains. {D}etection of target-site mutations ({L}1014{F}, {L}1014{S} and {N}1575{Y}) was performed using allelic discrimination {T}aq{M}an assays. {R}esults: {DDT} resistance was extremely high in all populations, regardless of molecular form, with no observed mortality after 300 min exposure. {I}n both {DDT}-survivors and non-exposed mosquitoes, {GSTE}2 and {GSTD}3 were over-expressed in the {M} form at 4.4-fold and 3.5-fold in {C}otonou and 1.5-fold and 2.5-fold in {M}alanville respectively, when compared to the susceptible strain. {T}he {CYP}6{M}2 and {CYP}6{P}3 were over-expressed at 4.6-fold and 3.8-fold in {C}otonou and 1.2-fold and 2.5-fold in {M}alanville respectively. {I}n contrast, no differences in {GSTE}2 and {CYP}6{M}2 were observed between {S} form mosquitoes from {T}ori-{B}ossito and {B}ohicon compared to susceptible strain. {T}he 1014 {F} allele was fixed in the {S}-form and at high frequency in the {M}-form (0.7-0.914). {T}he frequency of 1575{Y} allele was 0.29-0.36 in the {S}-form and nil in the {M}-form. {T}he 1014{S} allele was detected in the {S} form of {A}n. gambiae in a 1014 {F}/1014{S} heterozygous specimen. {C}onclusion: {O}ur results show that the kdr 1014 {F}, 1014{S} and 1575{Y} alleles are widespread in {B}enin and the expression of two candidate metabolic markers ({GSTE}2 and {CYP}6{M}2) are over-expressed specifically in the {M}-form.},
  keywords = {{A}n. gambiae ; {I}nsecticide resistance ; q{PCR} ; {K}dr mutation ; {V}ector control ; {M}etabolic enzymes ; {BENIN}},
  booktitle = {},
  journal = {{P}arasites and {V}ectors},
  volume = {7},
  numero = {},
  pages = {art. 409 [9 ]},
  ISSN = {1756-3305},
  year = {2014},
  DOI = {10.1186/1756-3305-7-409},
  URL = {https://www.documentation.ird.fr/hor/fdi:010062540},
}