Abstract
A summary is presented of a detailed clinical study of 34 patients with childhood progressive muscular dystrophy. The clinical findings become apparent in the first few years of life, and a characteristic and symmetrical pattern of muscular atrophy develops in childhood. The large pelvic girdle muscles are the first involved in a process which spreads centrifugally in an insidious fashion to produce extreme muscular disability. Most of the patients are severely disabled in adolescence and die then or in early adult life. None of these patients had had children. Among 33 kindreds in which 61 cases of the disorder are known to have occurred, the data are consistent with the interpretation that it is inherited as a sex-linked recessive trait, but with a mutation rate of approx. 1.0 x 10-4. This high mutation rate accounts for the many apparently sporadic cases of childhood progressive muscular dystrophy.