When concomitant platelet activity is assessed, no difference can be found in plasma TGFβ1 concentrations between patients with Marfan syndrome with dilated aortic roots or previous surgery and control subjects.77 Given the evidence for its role in the progression of aortopathy, active TGFβ1 could be a useful marker of disease progression and a guide to effective medical treatment. The gene discussed is TGFB1; the disease is Marfan syndrome.