Fig. 1From: Glutathione S-transferase M1 and T1 genes deletion polymorphisms and risk of developing essential hypertension: a case-control study in Burkina Faso population (West Africa)GSTM1 and GSTT1 genes deletion frequency in African countries [37,38,39,40,41,42,43,44,45,46]. Legend: Pie charts show frequency of GSTM1-null (red) and GSTT1-null (yellow) frequency in each countryBack to article page