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Three β hemoglobin variants are found in high polymorphic frequencies in West Africa. With various fitness values for the ten genotypes, mutation rates, and gene flow patterns, the specific features of the dines for these hemoglobin variants can be simulated. For the fitness values postulated by recent investigators, the dines are unstable but approach their present shape between 180 and 200 generations after malaria has become endemic in West Africa and resulted in high fitness values for the heterozygotes for these β hemoglobin variants. This seems to be in agreement with the history of agriculture, human population history, and malaria epidemiology in West Africa. Although these simulations are not able to indicate more plausibility for a specific set of fitness values, they do emphasize the predominant role of selection in determining clinal variation at the β hemoglobin locus.