Friedreich's disease--a family study.

Friedreich's disease occurring in 4 male siblings in a sibship of seven caused cardiac and neurological abnormalities and one twin of an affected member died in cardiac failure; at autopsy characteristic pathological features of Friedreich's disease were demonstrated in the nervous system and heart. One female sibling had a patent ductus arteriosus which was treated surgically and a continuous murmur was present in another sister but cardiac catheterization in childhood had been normal.