G6PD and HBB polymorphisms in Senegalese population: prevalence and correlations with clinical malaria

Abstract Background Several genetic polymorphisms were reported to be prevalent among populations living in tropical endemic regions and induce protection against malaria. In this study, we investigated the prevalence of key malaria-protective polymorphisms in G6PD and HBB genes in a Senegalese population. Methods We performed a retrospective study in 323 samples from patients recruited in hospitals located in three different endemic areas where malaria episodes were confirmed. Patients enrolled were classified in two groups: severe (153 patients) and uncomplicated malaria (170 patients). PCR and DNA sequencing assessed host genetic polymorphisms in HBB and G6PD. Using a multivariate regression and additive model, estimates the impact of human HBB and G6PD polymorphisms on malaria incidence were performed. Results We identified 12 SNPs in HBB gene. Among them, 6 SNPs (rs7946748, rs7480526, rs10768683, rs35209591, HbS (rs334) and rs713040) were detected with high frequencies in global population. The MAF of the sickle cell HbS polymorphism was estimated to 0.026, 0.069 and 0.035; and HbC polymorphism was estimated to be 0, 0.009, 0.029, in SM, UM and CTR group respectively. The MAF of G6PD deficiency polymorphisms such as G6PD-202 G>A were 0.022, 0.032 and 0.018 in SM, UM and CTR, respectively. Analysis of selected HbS polymorphism showed significant association with protection against severe malaria with a significant p-value = 0.033 (OR 0.38, 95%CI: 0.16–0.91). Surprisingly, HbC polymorphism is not a protective variant in our population. Finally, we found that the selected SNPs were associated to biological parameters such as PNE, PNB and lymphocytes. Conclusion Our data report at the first time the prevalence of HBB and G6PD mutations in senegalese population. These deficiencies are very common in West Africa endemic regions such as Gambia, Mali and Burkina Faso. Our findings show the important role of genetic factors in malaria outcome and these genetic markers could be good tools for malaria diagnosis and prognosis. Keywords : severe malaria, HBB, G6PD, Polymorphisms, Senegal, severe malaria.