Facioscapulohumeral Muscular Dystrophy

UMMS Affiliation

Wellstone Muscular Dystrophy Program, Department of Neurology; Emerson Lab

Publication Date


Document Type



Cell Biology | Cellular and Molecular Physiology | Congenital, Hereditary, and Neonatal Diseases and Abnormalities | Developmental Biology | Musculoskeletal Diseases | Nervous System Diseases


Facioscapulohumeral Muscular Dystrophy is a common form of muscular dystrophy that presents clinically with progressive weakness of the facial, scapular, and humeral muscles, with later involvement of the trunk and lower extremities. While typically inherited as autosomal dominant, facioscapulohumeral muscular dystrophy (FSHD) has a complex genetic and epigenetic etiology that has only recently been well described. The most prevalent form of the disease, FSHD1, is associated with the contraction of the D4Z4 microsatellite repeat array located on a permissive 4qA chromosome. D4Z4 contraction allows epigenetic derepression of the array, and possibly the surrounding 4q35 region, allowing misexpression of the toxic DUX4 transcription factor encoded within the terminal D4Z4 repeat in skeletal muscles. The less common form of the disease, FSHD2, results from haploinsufficiency of the SMCHD1 gene in individuals carrying a permissive 4qA allele, also leading to the derepression of DUX4, further supporting a central role for DUX4. How DUX4 misexpression contributes to FSHD muscle pathology is a major focus of current investigation. Misexpression of other genes at the 4q35 locus, including FRG1 and FAT1, and unlinked genes, such as SMCHD1, has also been implicated as disease modifiers, leading to several competing disease models. In this review, we describe recent advances in understanding the pathophysiology of FSHD, including the application of MRI as a research and diagnostic tool, the genetic and epigenetic disruptions associated with the disease, and the molecular basis of FSHD. We discuss how these advances are leading to the emergence of new approaches to enable development of FSHD therapeutics.


Facioscapulohumeral Muscular Dystrophy

DOI of Published Version



DeSimone AM, Pakula A, Lek A, Emerson CP Jr. Facioscapulohumeral Muscular Dystrophy. Compr Physiol. 2017 Sep 12;7(4):1229-1279. doi: 10.1002/cphy.c160039. PMID: 28915324. Link to article on publisher's site

Journal/Book/Conference Title

Comprehensive Physiology

Related Resources

Link to Article in PubMed

PubMed ID