Single Nucleotide Polymorphisms (SNPs) in the elastin gene (ELN), which harbours causative mutations for supravalvular aortic stenosis in Williams–Beuren syndrome (OMIM reference: #194050) (Perdu & Jeunemaitre, Unpublished data), as well as in the alpha1-antitrypsin gene (AAT) [42], were distributed evenly in patients with FMD and healthy controls or patients with essential hypertension. The gene discussed is ELN; the disease is hypertensive disorder.