DILATED CARDIOMYOPATHY AND THE DYSTROPHIN GENE - AN ILLUSTRATED REVIEW

Cardiomyopathy is often found in patients with Duchenne and Becker mus cular dystrophy, which are X Linked muscle diseases caused by mutation s in the dystrophin gene. Dystrophin defects present in many different ways and cases of mild Becker muscular dystrophy have been described in which cardiomyopathy was severe. Female carriers of Duchenne muscul ar dystrophy can develop symptomatic skeletal myopathy alone or combin ed with dilated cardiomyopathy. They can also develop dilated cardiomy opathy alone. X Linked dilated cardiomyopathy has been found in associ ation with dystrophin defects. The relation between the molecular defe cts and the cardiac phenotypes has not yet been established. New mutat ions in the dystrophin gene are common and such mutations cause one th ird of the cases with Duchenne and Becker muscular dystrophy. This mea ns that sporadic cases of cardiomyopathy caused by dystrophin defects are likely. This paper reports such a case in a boy of 14 who died of dilated cardiomyopathy. Before the cardiac investigation, which was pe rformed one month before he died, he had not complained of muscular we akness. He had minor signs of limb girdle myopathy and slightly increa sed concentrations of serum creatine kinase. He was found to have an u nusual deletion in the dystrophin gene.