Vascular Ehlers-Danlos Syndrome (vEDS) is an autosomal dominant condition; a child only has to inherit a defect in the COL3A1 gene from one parent to have the disorder. About half of people with vascular Ehlers-Danlos syndrome inherited the COL3A1 mutation from an affected parent. The other half of people with the condition have a spontaneous disease-causing mutation; that is, they are the first person in their family to have vascular Ehlers-Danlos syndrome. Each child of an affected parent has