Emery-Dreifuss muscular dystrophy with unusual features.

Two families with Emery-Dreifuss muscular dystrophy (EMD) are described. Several unusual features for EMD are emphasized. One of the patients had severe neuromuscular disability with inability to walk during early childhood. This patient also had mild bifacial paresis. His brothers had the typical slow progression of EMD. In some of the patients, muscle weakness distribution was more widespread than has usually been reported, with prominent involvement of finger extensors. It is suggested that there is a wide phenotypic spectrum in EMD. In both families, the disease segregated with markers spanning the EMD locus in Xq28.