KLK4 (r = 0.50, p = 0.02) (Figure 3A) correlated positively with age in T2D only, whilst IGFBP4 (r = 0.58, p = 0.004) (Figure 3B) correlated negatively with age in T2D only. The gene discussed is KLK4; the disease is type 2 diabetes mellitus.