TGFB1 and keratoconus: This process is regulated, amongst others, by TGF-β signaling [60, 61] Not surprisingly, a known systemic disease, Marfan syndrome, which is associated with TGF-β pathway mutations may also manifest with KC [62] Other anterior segment pathologies besides KC have been described to occur more commonly in patients with Marfan syndrome, namely: megalocornea, corneal flattening or scleral thinning.