TGF-β is a multifunctional peptide involved in T-cell generation and associated with susceptibility to KD, formation of CAA in KD, aortic root dilatation (Loeys-Dietz syndrome and abdominal aortic aneurysm), and response to IVIG treatment [19,20]. The gene discussed is TGFB1; the disease is abdominal aortic aneurysm.