SMAD3 and aneurysm: Mutations in SMAD3 were initially described as the genetic cause of aneurysms‐osteoarthritis syndrome, but because of the many overlapping clinical features with LDS, including hypertelorism, bifid uvula, arterial tortuosity, and widespread and aggressive aneurysms, it is now also classified as LDS type 3 (LDS3) (MacCarrick et al., 2014).