Targeting genes involved in sexual determinism for vector or pest control purpose, requires a better understanding of their polymorphism in natural populations in order to ensure a rapid spread of the construct. By using genomic data from An. gambiae s.l., we analyzed the genetic variation and the conservation score of the fru gene in 18 natural populations across Africa. A total of 34339 SNPs were identified including 3.11% non-synonymous segregating sites. Overall, the nucleotide diversity was low and the Tajima's D neutrality test was negative indicating an excess of low frequency SNPs in the fru gene. The allelic frequencies of the non-synonymous SNPs were low (freq < 0.26) except two SNPs identified at high frequencies (freq > 0.8) in the Zinc-finger A and B protein domains. The conservation score was variable throughout the fru gene with maximum values in the exonic compared to the intronic regions. These results showed a low genetic variation in overall the exonic regions especially the male sex-specific exon and the BTB-exon 1 of the fru gene. These findings are crucial for the development of a gene drive construct targeting the fru gene that can rapidly spread without encountering resistance in wild populations.

Abstract: In 2016, we conducted an entomological survey in a railway transect between Banfora and Ouagadougou, Burkina Faso. The aim was to evaluate the risk factors for arbovirus epidemics, including vector infection status, in areas representative of the country. Aedes aegypti mosquitoes were collected at larval stage from four study sites and reared until adult stage and kept in RNAlater for detection of arbovirus RNA. In the laboratory, the mosquito specimens were screened for dengue virus (DENV) and chikungunya virus (CHIKV) using one step real-time qRT-PCR. We detected one DENV-2 positive pool from Ouagadougou, giving a minimum infec-tion rate (MIR) of 16.67, and 6 CHIKV positive pools, giving a MIR of 66.67 from Ouagadougou, but also in Banfora and Boromo. The qRT-PCR is a useful tool for the surveillance of arboviruses of public health importance in Burkina Faso and may be incorporated into disease surveillance and control programs in Burkina Faso.

Bactrocera dorsalis Hendel is a highly invasive horticultural pest of major economic importance worldwide. In Burkina Faso, it is one of the main insect pests constraining the mango production and export. Understanding the biology and the genetic dynamics of this insect pest provide cru-cial information for the development of effective control measures. The aim of this study was to understand the distribution, diversity and genetic structure of B. dorsalis in Burkina Faso. Male flies were collected transversally in Burkina Faso and analyzed by PCR using 10 microsatellite markers. The results showed an abundance of B. dorsalis varying from 87 to 2986 flies per trap per day in the different sampling sites. Genetic diversity was high in all sites with an average Shan-non's Information Index (I) of 0.72 per site. Gene flow was high between study populations and ranged from 10.62 to 27.53 number of migrants. Bayesian admixture analysis showed no evi-dence of structure while Discriminant Analysis of Principal Components identified three weakly separated clusters in the population of B. dorsalis in Burkina Faso. The results of this study could be used to optimize the effectiveness of current control interventions and to guide the imple-mentation of new, innovative and sustainable strategies.