Genetic specificity and potential for local adaptation between dengue viruses and mosquito vectors Lambrechts, Louis Chevillon, Christine Albright, R.G. Thaisomboonsuk, B. Richardson, J.H. Jarman, R.G. Scott, T.W. Background: Several observations support the hypothesis that vector-driven selection plays an important role in shaping dengue virus (DENV) genetic diversity. Clustering of DENV genetic diversity at a particular location may reflect underlying genetic structure of vector populations, which combined with specific vector genotype x virus genotype (G x G) interactions may promote adaptation of viral lineages to local mosquito vector genotypes. Although spatial structure of vector polymorphism at neutral genetic loci is well-documented, existence of G x G interactions between mosquito and virus genotypes has not been formally demonstrated in natural populations. Here we measure G x G interactions in a system representative of a natural situation in Thailand by challenging three isofemale families from field-derived Aedes aegypti with three contemporaneous low-passage isolates of DENV-1. Results: Among indices of vector competence examined, the proportion of mosquitoes with a midgut infection, viral RNA concentration in the body, and quantity of virus disseminated to the head/legs (but not the proportion of infected mosquitoes with a disseminated infection) strongly depended on the specific combinations of isofemale families and viral isolates, demonstrating significant G x G interactions. Conclusion: Evidence for genetic specificity of interactions in our simple experimental design indicates that vector competence of Ae. aegypti for DENV is likely governed to a large extent by G x G interactions in genetically diverse, natural populations. This result challenges the general relevance of conclusions from laboratory systems that consist of a single combination of mosquito and DENV genotypes. Combined with earlier evidence for fine-scale genetic structure of natural Ae. aegypti populations, our finding indicates that the necessary conditions for local DENV adaptation to mosquito vectors are met. 2009 text https://www.documentation.ird.fr/hor/fdi:010046256 fdi:010046256 Lambrechts Louis, Chevillon Christine, Albright R.G., Thaisomboonsuk B., Richardson J.H., Jarman R.G., Scott T.W.. Genetic specificity and potential for local adaptation between dengue viruses and mosquito vectors. 2009, 9, 160 EN