The yellow fever mosquito, Aedes aegypti, is a well known vector of yellow fever (YF) and dengue fever (DEN) flaviviruses. Subspecies and populations of Ae. aegypti vary widely in their ability to transmit flaviviruses. Studies have shown that a midgut barrier to infection exists in the West African subspecies Ae. aegypti formosus. In the other subspecies, Ae aegypti aegypti, we demonstate that viral replication is regulated by genes that control disseminated infection rate. In both subspecies, levels of virus infection vary quantitatively among individuals and are subject to random environmental effects. Recent molecular and statistical advances enable geneticists to map loci affecting the expression of quantitative traits. These have been termed quantitative trait loci (QTLs). The first goal of this project is to map QTLs that control vector competence for DEN virus in Ae aegypti. The genetic markers arising from this project will be tested as biomarkers of DEN susceptibility in populations of Ae aegypti in dengue endemic areas in Mexico. This is a specific aim of another proposal being submitted by Dr. Barry Beaty in response to this PA. The second goal of the proposed work is to use marker-assisted selection (MAS) to generate strains of Ae aegypti that carry the midgut barrier genes in combination with genes that regulate the disseminated infection rate. These strains may be completely refractory to DEN virus and will provide an exceptional opportunity to elucidate the genetic mechanisms underlying DEN transmission. These strains may also have the potential for release into endemic areas of DEN virus transmission. Another specific aim of the Beaty proposal is to identify genetically isolated populations in DEN endemic regions of Mexico.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Small Research Grants (R03)
Project #
5R03AI041436-03
Application #
2887466
Study Section
Special Emphasis Panel (ZAI1-PRJ-M (M1))
Program Officer
Aultman, Kathryn S
Project Start
1997-08-01
Project End
2001-07-31
Budget Start
1999-08-01
Budget End
2001-07-31
Support Year
3
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Colorado State University-Fort Collins
Department
Microbiology/Immun/Virology
Type
Schools of Veterinary Medicine
DUNS #
112617480
City
Fort Collins
State
CO
Country
United States
Zip Code
80523
Fagerberg, A J; Fulton, R E; Black , W C (2001) Microsatellite loci are not abundant in all arthropod genomes: analyses in the hard tick, Ixodes scapularis and the yellow fever mosquito, Aedes aegypti. Insect Mol Biol 10:225-36
Fulton, R E; Salasek, M L; DuTeau, N M et al. (2001) SSCP analysis of cDNA markers provides a dense linkage map of the Aedes aegypti genome. Genetics 158:715-26
Black 4th, W C; Baer, C F; Antolin, M F et al. (2001) Population genomics: genome-wide sampling of insect populations. Annu Rev Entomol 46:441-69
Bosio, C F; Fulton, R E; Salasek, M L et al. (2000) Quantitative trait loci that control vector competence for dengue-2 virus in the mosquito Aedes aegypti. Genetics 156:687-98
Bosio, C F; Beaty, B J; Black 4th, W C (1998) Quantitative genetics of vector competence for dengue-2 virus in Aedes aegypti. Am J Trop Med Hyg 59:965-70