Martin J Donnelly

..Here we present a reliable and potentially high throughput method for screening An. gambiae for the kdr mutation...

..Host-seeking activity peaked between 2-3 am, indicating that insecticide-treated bednets should be an effective control method...

..However, we emphasize that kdr genotype might explain only a portion of heritable variation in resistance and that diagnostic assays to test the importance of other resistance mechanisms in field populations are required...

..This commentary reflects the discussions held during the meeting and aims to inform researchers and policy makers of the potential for containing and reversing the emerging problem of urban malaria...

..These genes may constitute an important general defence mechanism against insecticides. Intriguingly, the levels of expression of these genes were strongly correlated suggesting a common regulatory mechanism...

..Intriguingly, the association between DDT resistance and the presence of L1014S is consistent with a co-dominant effect, with heterozygous individuals showing an intermediate phenotype...

..We quantified and investigated the impacts of these key variables in a large-scale association study of a strongly selected trait of medical importance: pyrethroid resistance in the African malaria vector Anopheles gambiae...

..Registered trial number ISRCTN42261314; http://www.controlled-trials.com/ISRCTN42261314]...

..This is the first study to demonstrate the capacity of a P450 identified in wild A. gambiae to metabolise insecticides. The findings add to the understanding of the genetic basis of insecticide resistance in wild mosquito populations...

..To further association studies in Anopheles gambiae we conducted a major resequencing programme, primarily targeting regions within or close to candidate genes for insecticide resistance...

..16 and a dominance coefficient of 0.25. Our data show that strong, recent positive selective events, such as those caused by insecticide resistance, can be identified in wild insect populations...

..Although three enzyme families (cytochrome P450s, glutathione S-transferases and carboxylesterases) have been widely associated with insecticide detoxification the role of individual enzymes is largely unknown...

..Thus, in the sampled area of West Africa, lack of differentiation between M and S forms likely reflects substantial introgression, and ecological barriers appear to be of greater importance in restricting gene flow...

..Secondary objectives were to compare prevalences of clinical malaria, anaemia, intestinal parasite infections, and malnutrition between these communities; and to identify potential risk factors for P. falciparum infection and anaemia...

..This highlights the potential for islands comprising a relatively small fraction of the genome to play an important role in early-stage speciation when reproductive isolation is limited...

..Our findings indicate that African urban poor are seriously affected by malaria and that irrigated agriculture may increase this risk...

..The development of a propensity for feeding on the blood of humans in some species of the Subgroup would have led to the transmission of malaria protozoa and filarial nematodes...

..This article assesses how successful molecular genetic techniques have been in revealing new population patterns...

..We review several lines of evidence suggesting that such costs do occur, that they may be relatively large, and review their likely impact on the evolution of drug resistance in the malaria parasite Plasmodium falciparum...

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..However, there are few reports comparing the performance of these different assays. In this study, two new high-throughput assays were developed and compared with four established techniques...

..Recently, a high-throughput assay based on TaqMan single nucleotide polymorphism genotyping that detects and discriminates An. gambiae s.s and An. arabiensis has been reported...

..This has important practical implications for the management and sustainability of malaria vector control programs...

..0% in the area with agricultural insecticide use. The presence of the kdr alleles in An. arabiensis in Sudan emphasizes the need to develop appropriate resistance monitoring and management strategies for An. arabiensis...

..In M-form populations surveyed to date, only the L1014F mutation has been found, although less widespread and at lower frequencies than in sympatric S-form populations...

..Before any release of transgenic mosquitoes can be envisaged, we need an accurate picture of the differentiation between the two molecular forms of An. gambiae, termed M and S, which are of uncertain taxonomic status...

..The most vulnerable group, the urban poor, should be prioritized when designing control measures. This would require careful assessment of the malaria risk pattern in any city to guide an integrated control program...

..We found indication of mitochondrial DNA introgression occurring among forms in putative hybrid zones...

..We discuss additional approaches that will be needed to identify genes and nucleotides that control phenotypes in field collected organisms, focusing specifically on ongoing studies of genes conferring resistance to insecticides...