DETECTION OF PARTIAL DELETION AND PARTIAL DUPLICATION OF DYSTROPHIN GENE IN JAPANESE PATIENTS WITH DUCHENNE OR BECKER MUSCULAR-DYSTROPHY

The dystrophin gene was analyzed in 59 Japanese patients with Duchenne muscular dystrophy (DMD) from 48 unrelated families, including 11 pai rs of siblings, and three patients with Becker muscular dystrophy (BMD ) from two unrelated families, including one pair of siblings. The rel ationship between the type of gene abnormality and clinical symptoms w as examined. Twenty-seven of 50 (54.0%) unrelated DMD or BMD patients were found to have partial deletions, and five (10%) appeared to have partial duplications in the dystrophin gene. Nine DMD patients, includ ing three pairs of siblings, showed mental retardation, the existence of which was coincident in each pair of siblings, but deletion of an i dentical exon was not always related to mental retardation in unrelate d patients.