Facioscapulohumeral muscular dystrophy (FSHD) has been localized to the 4q35-qter region of chromosome 4. Linkage analyses of two polymorphic markers from the region, D4S139 and D4S163, have been carried out using four large multigenerational FSHD families. The results indicate that both markers are closely linked to FSHD, with D4S139 being the closest proximal marker to FSHD.