FUNCTIONAL-SIGNIFICANCE OF DYSTROPHIN-POSITIVE FIBERS IN DUCHENNE ANDBECKER MUSCULAR-DYSTROPHY

In this study, the ratios of dystrophin-positive (+), partially defici ent (+/-), and deficient (-) fibers were investigated immunohistochemi cally in 28 Duchenne muscular dystrophy (DMD) and 4 Becker muscular dy strophy (BMD) patients using Dys I (midrod), Dys II (COOH-terminal), a nd Dys III (NH2-terminal) antibodies. In the biopsies of DMD patients, Dys II was negative in all cases; the mean ratio of Dys I (+) fibers was 0.05%, Dys I (+/-) 1.02%, Dys III (+) 0.27%, and Dys III (+/-) 0.7 5%. There was no correlation between these (+) or (+/-) fibers and the severity of clinical or laboratory findings. In BMD patients, it was shown that amino and carboxyl terminals of dystrophin could be affecte d in addition to the midportion.