THE USE OF MICROSATELLITES TO STUDY GENE FLOW IN NATURAL-POPULATIONS OF ANOPHELES MALARIA VECTORS IN AFRICA - POTENTIAL AND PITFALLS

The potential of microsatellites as population genetic markers in the malarial vectors Anopheles gambiae and Anopheles arabiensis was assess ed using 4 loci. Substantial genetic divergence was found not only bet ween these species but also between the Mopti and Forest chromosomal f orms of An. gambiae, demonstrating that microsatellites do have the po wer to detect barriers to gene Bow in these mosquitoes. However, appli cation and interpretation of microsatellites was not necessarily strai ghtforward. Despite the use of semiautomated fluorescent technology th at enabled fragment sizes to be determined precisely, some difficulty was encountered in allele classification. Sequence analysis revealed i nsertions/deletions and base changes in the flanking regions of the mi crosatellite as the probable cause of this problem. The implications o f this and other potential pitfalls in the use of microsatellites to s tudy vector populations are discussed.