ABSTRACT
FSHD Facioscapulohumeral Muscular Dystrophy: Clinical Medicine and Molecular Cell Biology, edited by Meena Upadhyaya and David N.Cooper. © 2004 Garland/BIOS Scientific Publishers Limited, Abingdon.
23.1 Introduction
23.1.1 Deletion of D4Z4 in FSHD
FSHD is an autosomal dominant neuromuscular disease that initially affects the facial, shoulder girdle and upper arm musculature (Tawil et al., 1998; Padberg and Adams, 2000). Asymmetric involvement of specific muscle groups is common and occasionally the complete absence of a muscle, e.g. the pectoralis, is noted. Such findings suggest a developmental defect, although FSHD is often not recognized clinically until the second or third decade of life (Lunt et al., 1989). Extramuscular manifestations of the disease frequently include retinal vascular anomalies, sensorineural hearing loss and, in severe cases, epilepsy and mental retardation (Padberg et al., 1992; Funakoshi et al., 1998). Males are often more severely affected and have an earlier age of onset than females (Zatz et al., 1998).
