Seasonal distribution of Anopheles funestus chromosomal forms from Burkina Faso.

Background Previous studies of Anopheles funestus chromosomal inversion polymorphisms in Burkina Faso showed large departures from Hardy-Weinberg equilibrium and linkage disequilibrium among inversions located on different chromosomes, implying the existence of two taxonomic units ("chromosomal forms") with limited genetic flow. One chromosomal form, named Folonzo, is highly polymorphic for alternative rearrangements of 3Ra, 3Rb, 2Ra, and 3La; the other, Kiribina, is predominantly characterized by the standard arrangement of these inversions. To investigate the temporal distribution of these chromosomal forms, further collections were carried out in two villages near Ouagadougou where they are found in sympatry.