title: Exploring the origin and degree of genetic isolation of Anopheles gambiae from the islands of São Tomé and Príncipe, potential sites for testing transgenic-based vector control.
abstract: The evolutionary processes at play between island and mainland populations of the malaria mosquito vector Anopheles gambiae sensu stricto are of great interest as islands may be suitable sites for preliminary application of transgenic-based vector control strategies. São Tomé and Príncipe, located off the West African coast, have received such attention in recent years. This study investigates the degree of isolation of An. gambiae s.s. populations between these islands and the mainland based on mitochondrial and ribosomal DNA molecular data. We identify possible continental localities from which these island populations derived. For these purposes, we used F ST values, haplotype networks, and nested clade analysis to estimate migration rates and patterns. Haplotypes from both markers are geographically widespread across the African continent. Results indicate that the populations from São Tomé and Príncipe are relatively isolated from continental African populations, suggesting they are promising sites for test releases of transgenic individuals. These island populations are possibly derived from two separate continental migrations. This result is discussed in the context of the history of the African slave trade with respect to São Tomé and Príncipe.
authors.affiliation: Department of Zoology, Weber State University, 2505 University Circle Ogden, UT, USA.
authors.forename: Jonathon C
authors.initials: JC
authors.lastname: Marshall
authors.affiliation: Centro de Malária e Outras Doenças Tropicais, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa Lisbon, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Pinto
authors.affiliation: DBL Institute for Health Research and Development Charlottenlund, Denmark.
authors.forename: Jacques Derek
authors.initials: JD
authors.lastname: Charlwood
authors.affiliation: Dipartimento di Biologia, Università di Roma "Tor Vergata" Rome, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Gentile
authors.affiliation: Department of Public Health Sciences University of Rome "La Sapienza" Rome, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Santolamazza
authors.affiliation: Laboratoire de l'Institut de Recherche Pour le Developpement (IRD), UR 016, Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC) Yaoundé, Cameroun.
authors.forename: Frèdèric
authors.initials: F
authors.lastname: Simard
authors.affiliation: Department of Public Health Sciences University of Rome "La Sapienza" Rome, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Della Torre
authors.affiliation: Vector Group, Liverpool School of Tropical Medicine Pembroke Place, Liverpool, UK.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Donnelly
authors.affiliation: Department of Ecology and Evolutionary Biology, Yale University New Haven, CT, USA.
authors.forename: Adalgisa
authors.initials: A
authors.lastname: Caccone
keywords: Anopheles gambiae; island colonization; malaria; mitochondrial DNA; phylogeography; ribosomal DNA