Diabetes patients treated with metformin had significantly lower fibulin-1 levels than patients not treated with metformin, 88 ± 23 vs 103 ± 34 μg/mL, p < 0.05, despite comparable glomerular filtration rates, 78 ± 16 vs 75 ± 14 mL/min/1.73 m2, p = 0.28. The gene discussed is FBLN1; the disease is diabetes mellitus.