MMP-2 plasma levels were 401.5 ng/ml (142.4–633.4 ng/ml) in the PDR group, 277.9 ng/ml (118.0–473.5 ng/ml) in the non-PDR group, and 260.8 ng/ml (44.8–428.2 ng/ml) in the non-DM group (p<0.001, Kruskal–Wallis ANOVA). The gene discussed is MMP2; the disease is diabetes mellitus.