Several studies have demonstrated that human abdominal aortic aneurysm dilation is accompanied by smooth muscle cell (SMC) apoptosis [56,57], and the resulting degenerated SMCs respond differently to TGF-β1 than healthy SMCs, contributing to changes in the cellular composition of the vascular wall [58]. The gene discussed is TGFB1; the disease is abdominal aortic aneurysm.