Nevertheless, nonglycemic lowering of measured HbA1c for 1 in 10 African American men who carry this G6PD variant, and 1 in a 100 African American women homozygous for this variant, could amount to 0.65 (95% CI 0.56–0.74) million African American adults in the US with a missed T2D diagnosis using HbA1c as a screening test. The gene discussed is G6PD; the disease is type 2 diabetes mellitus.