Oculopharyngeal muscular dystrophy (OPMD) is an autosomal dominant, late-onset, progressive disease that typically presents in the fifth or sixth decade with progressive swallowing difficulties (dysphagia), eyelid drooping (ptosis) and proximal limb weakness.

OPMD is caused by the abnormal expansion of a polyalanine tract within the coding region of poly(A) binding protein nuclear 1 (PABPN1).