Thursday, October 30, 2008

Marshall et al. EA 2008

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. Sao Tome´ and Prıncipe, 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 FST 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 Sao Tome´ and Prıncipe 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 Sao Tome and Prıncipe.

Marshall, JC, J Pinto, JD Charlwood, G Gabriele, F Santolamazza, F Simard, A della Torre, MJ Donnelly, and A Caccone. 2008. Exploring the origin and degree of isolation of Anopheles gambiae from the islands of Sao Tome and Principe, potential sites for testing transgenic-based vector control. Evolutionary Applications 1: 631-644.