From a medical perspective, the Anopheles gambiae complex is arguably the most important group of insects; it is the primary vector of malaria in Africa, and hence the world. The goal of these projects is to understand the evolutionary genetics of the group; this includes understanding the genetic basis of sterility barriers between species and the dynamics of gene exchange between species. Previous research has indicated that two closely related species may be exchanging genetic material by hybridizing in nature, the phenomenon known as introgression. But it appears that not all parts of a species genome are equally able to cross species boundaries. Using genetic markers (microsatellites) we intend to directly test which parts of the genome are responsible for sterility barriers. This will be done by making interspecific crosses, backcrossing fertile hybrid females to males of each species, assessing the reproductive status of the backcross progeny, and genotyping them for at least 24 microsatellites spread evenly across the genome. When regions responsible for sterility are identified, finer scale mapping will be done by increasing the density of microsatellite markers. In a related study, we will determine which parts of the genome are able to persist in freely breeding backcross populations for up to twenty generations. The second project concerns the dynamics of introgression. In particular, the question of whether the introgression is an ancient phenomenon or a recent, ongoing process will be addressed. This project will involve examination of DNA sequences in a chromosome inversion, the """"""""a"""""""" inversion of the left arm of the second chromosome (2La), for which there is good evidence of interspecies transfer. The history of this inversion will be determined using phylogenetic procedures and statistical analysis for the number on introgression events most consistent with the data. Understanding whether the two most important vectors of malaria in the world (An. gambiae and An. arabiensis) are exchanging genes is vitally important to control measures aimed at these species.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI046018-02
Application #
6374266
Study Section
Special Emphasis Panel (ZRG1-TMP (01))
Program Officer
Aultman, Kathryn S
Project Start
2000-04-01
Project End
2004-03-31
Budget Start
2001-04-01
Budget End
2002-03-31
Support Year
2
Fiscal Year
2001
Total Cost
$285,614
Indirect Cost
Name
Yale University
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
082359691
City
New Haven
State
CT
Country
United States
Zip Code
06520
Brown, Julia E; Evans, Benjamin R; Zheng, Wei et al. (2014) Human impacts have shaped historical and recent evolution in Aedes aegypti, the dengue and yellow fever mosquito. Evolution 68:514-25
Brown, Julia E; Obas, Vanessa; Morley, Valerie et al. (2013) Phylogeography and spatio-temporal genetic variation of Aedes aegypti (Diptera: Culicidae) populations in the Florida Keys. J Med Entomol 50:294-9
Powell, Jeffrey R; Tabachnick, Walter J (2013) History of domestication and spread of Aedes aegypti--a review. Mem Inst Oswaldo Cruz 108 Suppl 1:11-7
Somers, Gerard; Brown, Julia E; Barrera, Roberto et al. (2011) Genetics and morphology of Aedes aegypti (Diptera: Culicidae) in septic tanks in Puerto Rico. J Med Entomol 48:1095-102
Brown, Julia E; McBride, Carolyn S; Johnson, Petrina et al. (2011) Worldwide patterns of genetic differentiation imply multiple 'domestications' of Aedes aegypti, a major vector of human diseases. Proc Biol Sci 278:2446-54
Pappa, Vasiliki; Reddy, Michael; Overgaard, Hans J et al. (2011) Estimation of the Human Blood Index in malaria mosquito vectors in Equatorial Guinea after indoor antivector interventions. Am J Trop Med Hyg 84:298-301
Brown, Julia E; Scholte, Ernst-Jan; Dik, Marian et al. (2011) Aedes aegypti mosquitoes imported into the Netherlands, 2010. Emerg Infect Dis 17:2335-7
Parmakelis, Aristeidis; Russello, Michael A; Caccone, Adalgisa et al. (2008) Historical analysis of a near disaster: Anopheles gambiae in Brazil. Am J Trop Med Hyg 78:176-8
Manoukis, Nicholas C; Powell, Jeffrey R; Toure, Mahamoudou B et al. (2008) A test of the chromosomal theory of ecotypic speciation in Anopheles gambiae. Proc Natl Acad Sci U S A 105:2940-5
Schielke, Erika; Costantini, Carlo; Carchini, Gianmaria et al. (2007) Development of a molecular assay to detect predation on Anopheles gambiae complex larval stages. Am J Trop Med Hyg 77:464-6

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