Alert SA-AFUN-06 (Dgk)

Alert SA-AFUN-06 (Dgk)#

This alert reports selection signals on Chromosome X within the region 13,635,108-13,733,014 bp.

Selection signals#

Selection signals overlapping this genome region are shown in the figure below.

Cohorts affected#

Overlapping selection signals are found in the following cohorts.

Table 1. Cohorts with selection signals overlapping this selection alert.
Cohort Country Region District Taxon Year Quarter Sample Size
Democratic Republic of the Congo / Watsa / funestus / 2017 / Q4 Democratic Republic of the Congo Upper Uele Watsa funestus 2017 4 43
Cameroon / Mayo-Banyo / funestus / 2014 / Q3 Cameroon Adamaoua Mayo-Banyo funestus 2014 3 45
Ghana / Adansi Akrofuom / funestus / 2014 / Q1 Ghana Ashanti Region Adansi Akrofuom funestus 2014 1 31
Uganda / Tororo / funestus / 2014 / Q2 Uganda Eastern Region Tororo funestus 2014 2 49

Insecticide resistance genes#

The following genes are found within this genome region and may be driving recent positive selection based on evidence for an association with insecticide resistance. Please note that other genes are also within the affected genome region and may be driving selection.

LOC125760558 (Dgk, Rdga, AFUN2_000796, AFUN020012)#

This gene encodes a diacylglycerol kinase. This gene has not been directly implicated in resistance to pesticides in any insect species to date, but there are two hypotheses regarding a potential link to insecticide resistance in Anopheles based on studies in other species. (1) In several systems, Dgk genes act as negative regulators of synaptic transmission between cholinergenic neurons by limiting the amount of acetylcholine available at synaptic junctions. In C. elegans, loss of function mutations in a Dgk gene cause hyperactivity and hypersensitivity to aldicarb, a carbamate insecticide, presumably because of an increase in acetylcholine levels available at synaptic junctions. If Dgk performs a similar function in Anopheles, then a gain of function mutation might reduce sensitivity to carbamate and/or organophosphate insecticides. (2) In Drosophila melanogaster, the ortholog of this gene Rdga is expressed exclusively in the retina and modulates sensitivity to light, via the same pathway and mechanism described above. This gene is also under circadian control in Anopheles gambiae. If mutations in this gene affected sensitivity to light in Anopheles, and the gene is expressed under a circadian rhythm, then such mutations might also affect circadian behaviours, such as the timing of host-seeking and feeding behaviours. See also:

  • Miller et al. (1999) Goα and Diacylglycerol Kinase Negatively Regulate the Gqα Pathway in C. elegans

  • Rund et al. (2011) Genome-wide profiling of diel and circadian gene expression in the malaria vector Anopheles gambiae

  • Kientega et al. (2024) Whole-genome sequencing of major malaria vectors reveals the evolution of new insecticide resistance variants in a longitudinal study in Burkina Faso

See also#

  • Anopheles gambiae complex selection alert SA-AGAM-09.

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