THE INHERITANCE OF MUSCULAR DYSTROPHY: FURTHER OBSERVATIONS

Abstract

SUMMARY The results are reported of a survey of the mode of inheritance of muscular dystrophy as determined from a series of sixty‐seven cases occurring in seventeen families. In seven families containing cases of the Duchenne‐type muscular dystrophy there were thirty‐seven oases of which one appears to be female, although her polymorphonuclear leucocytes do not show female characteristics. Nevertheless in all families the mode of inheritance was characteristic of that due to a sex‐linked recessive gene. In three of the families the onset of the disease was as late as the second or third decade. In three families of facioscapulohumeral dystrophy there were at least eleven affected individuals including three abortive cases. The pattern of inheritance suggested that this disease is carried as an autosomal dominant character, though possibly with sex limitation (to females) or incomplete manifestation in some families. Nineteen cases of limb‐girdle dystrophy occurred in eight sibships of seven families; this form of the disease appears to be transmitted as an autosomal recessive character. I am grateful to Dr E. A. Carmichael for his encouragement and advice during the course of this study and to the physicians and Medical Committee of the National Hospital, Queen Square, for permission to review these cases. I also appreciate the advice of Prof. L. S. Penrose and Dr Ursula Philip and the help given by Dr W. M. Davidson of King's College Hospital, London, Dr Ursula Mittwoch of the Galton Laboratory, and Dr R. B. Thompson of Newcastle upon Tyne in sexing the nuclei of case IV. 1 of family D. 1. I also acknowledge with thanks financial assistance given by the Muscular Dystrophy Associations of America, Inc. and the invaluable help of my secretary, Mrs B. Wilson.