We found that there existed a significant genetic correlation between T2D and HCT (rg = −0.26 p = 0.03), HGB (rg = −0.24 p = 0.03), EOS (rg = 0.44 p = 0.05), PLT (rg = 0.35 p = 0.002) in Africans. The gene discussed is CYGB; the disease is type 2 diabetes mellitus.