Detection of Knockdown Resistance Mutations inAnopheles sacharovi(Diptera: Culicidae) and Genetic Distance withAnopheles gambiae(Diptera: Culicidae) Using cDNA Sequencing of the Voltage-Gated Sodium Channel Gene

Abstract

The knockdown resistance (kdr) mutation in the voltage-gated sodium channel gene (VGSCG), an important resistance mechanism against pyrethroids, was studied in Anopheles sacharovi Favre. It was found that the specific primers Agd1 and Agd2 used for polymerase chain reaction (PCR) amplification of Anopheles gambiae Giles VGSCG also amplified this genomic region in An. sacharovi. Comparison of the IIs4-IIs6 domain segments of the gene indicated 70% nucleotides common to both species and a genetic distance of 0.255 between them. Four different samples of pyrethroid-resistant An. sacharovi produced three types of amino acid, serine (TCG),leucine (TTG),and phenylalanine (TTT) at the kdr mutation point, whereas only two kdr mutations, leucine to phenylalanine and leucine to serine, occur in An. gambiae.

Detection of Broadly Distributed Sodium Channel Alleles Characteristic of Insect Pyrethroid Resistance in West Nile Virus VectorCulex pipiensComplex Mosquitoes in the United States

“…It also has recently been shown in An. sacharovi (Luleyap et al 2002). In Culex, only one study showed leucine to serine substitution resistance in a Chinese strain of Culex pipiens L. mosquitoes in 1999 (Martinez-Torres et al 1999).…”

Evidence for multiple origins of identical insecticide resistance mutations in the aphid Myzus persicae

“…The assumption that resistance arose recently is supported by the number of other species showing exactly the same pyrethroid-resistance polymorphisms. The L1014F mutation has been found in Musca domestica (Williamson et al, 1993), Blattela germanica (Dong, 1997), Haematobia irritans (Guerrero et al, 1997), Plutella xylostella (Schuler et al, 1998), Anopheles gambiae (Martinez-Torres et al, 1998), C. pipens (Martinez-Torres et al, 1999a) and Anopheles sacharovi (Luleyap et al, 2002). M918T has been found in M. domestica (Williamson et al, 1996) and H. irritans (Guerrero et al, 1997).…”

Differential resistance of insect sodium channels with kdr mutations to deltamethrin, permethrin and DDT

“…There are also reports of kdr mutations co-occurring in A. gambiae (Verhaeghen et al, 2006). L1014S is also present in Anopheles arabiensis (Diabate et al, 2004;Himeidan et al, 2007;Stump et al, 2004;Verhaeghen et al, 2006) and in Anopheles sacharovi from Turkey (Luleyap et al, 2002). With the scaling-up of malaria control efforts using indoor residual spraying with DDT and pyrethroids, and the use of pyrethroid treated bed nets, the continued selection of resistance may compromise control programmes (Czeher et al, 2008;Protopopoff et al, 2008).…”