Abnormal protein synthesis in facioscapulohumeral muscular dystrophy.

Recently we have observed that muscle polyribosomes obtained from patients with Duchenne muscular dystrophy (DMD) synthesize abnormally large amounts of collagen when combined with soluble enzymes derived from the same patient's muscle.' Increased protein synthesis in the carrier state of DMD has also been observed and has proved useful in the detection of h e t e r o ~ ~ ~ o t e s . ~ In this study, we tested four biochemical parameters in skeletal muscle from patients w i t h f a cioscapulohumeral (FSH) muscular dystrophy: (1) total ribosome concentration, (2) ribosome distribution, (3) in vitro amino acid incorporation by fractionated ribosomes, and (4) in vitro collagen synthesis. Because three of these parameters are abnormal in patients and two are abnormal in carriers of D M D , ' ~ ~ we wanted to know if similar distwbances in ribosomal protein synthesis are found in FSH muscular dystrophy.