7. Assessing the association between the 4.3kb structural
variant and Plasmodium infection.
Genomic DNA samples extracted from whole mosquitoes collected from Obout
in 2016 were screened to detect Plasmodium infection and grouped
into ‘infected’ (n=37) and ‘non-infected’ (n=42). These were genotyped
for the 4.3kb structural variant, showing a significant association
between SV+/SV+, SV+/SV- and SV-/SV- and infection status (χ2= 7.0; P =
0.031). The Plasmodium -infected group comprised 16.2% SV+/SV+,
43.2% SV+/SV- and 40.5%, SV-/SV-showing that the homozygous SV+/SV+
were less infected than the SV+/SV- and SV-/SV- genotypes (Figure 4B).
Hence the SV+/SV+ were less likely to be infected than SV-/SV- (OR:
4.05; CI: 2.2-7.3; P <0.001) while no significant difference
was observed between SV+/SV+ and SV+/SV- genotypes (OR: 1; CI:
1.5-474.6; P = 0.05). Comparison of the allelic distribution of the
4.3kb SV among infected and non-infected further supported the reducedPlasmodium infection in mosquitoes, with 57.8% SV+ being
non-infected against 45.2% SV-. The majority of Plasmodium-infected
mosquitoes had SV- alleles without the structural variant (62.1%),
while only 37.8% had SV+ alleles.