MODIFICATION IN THE FREQUENCY OF Hb C AND Hb S IN BURKINA FASO: AN INFLUENCE OF MIGRATORY FLUXES AND IMPROVEMENT OF PATIENT HEALTH CARE

Abstract

The incidence of hemoglobinopathies (Hb C and Hb S) is relatively high in West Africa. In order to calculate the gene frequency of these hemoglobinopathies, 6619 students from 23 local schools in Ouagadougou, Burkina Faso, West Africa, and 2582 individuals living in five villages near Ouagadougou, all situated in Savanna, were studied. As expected, the gene frequency in the city schools was 0.111 for the β^C gene and 0.051 for the β^S gene; in the five villages it was 0.122 for the β^C gene and 0.047 for the β^S gene. This data is somewhat different from that published in a previous study by Labie et al. in the humid Savanna region, that showed a higher prevalence of β^C (0.14) than β^S (0.03), and is in contrast to data from the arid Sahel region that showed a higher prevalence of β^S (0.1) compared to β^C (0.05). The higher rate of β^S and lower rate of β^C in students in Ouagadougou, and in the individuals living in the five villages near Ouagadougou, suggest the possible influence of migratory fluxes of the β^S gene from the country region of Sahel. The dramatic increase in the prevalence of Hb SS patients, not reported in the study of Labie et al., may be the result of reduced mortality due to environmental change. In addition, the improved health conditions of Hb SC and the increased life expectancy of Hb SS, may also have facilitated the increase of the β^S gene and the focus on secondary prevention for the control of correlated diseases.