Interrupted aortic arch in two siblings.

Two siblings with identical malformations consisting of complete interruption of the aortic arch, type B, ventricular septal defect, patent ductus arteriosus and anomalous origin of the right subclavian artery are described. Five other unrelated patients with interrupted aortic arch have been investigated in the years 1971--79. Of their 6 siblings, one had a coarctation of the aorta, while 5 were normal. Together with future reports this may help us to elucidate the genetics of this entity and may improve genetic counselling.