The Anopheles gambiae complex (Diptera: Culicidae) is the most important vector for malaria in Sub-Saharan Africa, besides other vectors such as Anopheles funestus. Malaria vector control should encompass specific identification, genetic diversity and population structure of An. gambiae to design vector control strategies.
The aim of this study was to determine the distribution of sibling species of the An. gambiae complex according to climatic regions related to cotton-growing or cotton-free areas by using polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP). Then, variation in mitochondrial cytochrome c oxidase 1
(COI) was used to assess the genetic structure within and between populations from our selected ecological zones.
At the sibling species level, the following proportions were found across all samples (n=180): An. coluzzii 65.56%, An. gambiae stricto sensu (s.s). 21.11%, and An. arabiensis 3.33%. Hybrids between An. gambiae s.s. and An. coluzzii (7.78%) and hybrids between An. coluzzii and An. arabiensis (2.22%) were found. The phylogenetic tree and Integer Neighbour-Joining (IntNJ) haplotype network did not reveal any distinct genetic structure pattern related to climatic or agricultural conditions in Burkina Faso. The Fst (Wright's F-statistic) values close to zero showed a free gene flow and no differentiation in An. gambiae complex populations. Furthermore, neutrality indices calculated by Tajima's D, Fu and Li's D⁎, Fu and Li's F⁎, Fu's Fs tests suggested an excess of rare mutations in the populations.
Overall, variation in the proportions of An. gambiae s.s., An. coluzzii and An. arabiensis was found according to climatic regions, but COI analysis did not evidence any population structuring of the An. gambiae complex. These scientific contributions can be used as a basis for further in-depth study of the genetic diversity of the An. gambiae complex for epidemiological risk assessment of malaria in Burkina Faso.

Anopheles gambiae s.l., rDNA, COI, genetic structure, Burkina Faso