G6PD and Schnyder corneal dystrophy: Recent studies in Tanzania found prevalence of 1.4% SCD, 15.9% to 19.7% SCT, 37.8% heterozygous α+ AT, 5.2% homozygous α+ AT, and 29.9% for combined heterozygous (G6PD(A)) and homozygous/hemizygous (G6PD(A-)) G6PD deficiency [12,13].