Unusual clinical presentations in patients harboring the facioscapulohumeral dystrophy 4q35 deletion

Facioscapulohumeral dystrophy (FSHD) is a dominantly inherited myopathy usually associated with a deletion at locus 4q35. Typically, FSHD patients present with a recognizable constellation of signs including weakness of facial, shoulder and pelvic girdle, humeral, and anterior foreleg muscles; preservation of some muscles including the deltoids; and other characteristic features including prominent scapular winging, anterior axillary folds, and horizontally positioned clavicles. We performed clinical and FSHD genetic studies on four patients with atypical clinical features who were cared for at a regional neuromuscular center. The four patients, each harboring 4q35 deletions, presented with atypical phenotypes including facial-sparing scapular myopathy, limb-girdle muscular dystrophy, distal myopathy, and asymmetric brachial weakness. This report demonstrates the expanding clinical heterogeneity in patients harboring the 4q35 deletion.