Case Studies on the Genetic and Clinical Diagnosis of Facioscapulohumeral Muscular Dystrophy

Johanna Hamel; Rabi Tawil

doi:10.1016/j.ncl.2020.03.003

Case Studies on the Genetic and Clinical Diagnosis of Facioscapulohumeral Muscular Dystrophy

Neurol Clin. 2020 Aug;38(3):529-540. doi: 10.1016/j.ncl.2020.03.003.

Authors

Johanna Hamel¹, Rabi Tawil²

Affiliations

¹ Department of Neurology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 673, Rochester, NY 14642, USA. Electronic address: Johanna_Hamel@URMC.Rochester.edu.
² Department of Neurology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 673, Rochester, NY 14642, USA.

PMID: 32703466
DOI: 10.1016/j.ncl.2020.03.003

Abstract

Facioscapulohumeral muscular dystrophy is the second most common adult muscular dystrophy and is caused by DUX4 protein. DUX4 is expressed when the locus on chromosome 4q35 is hypomethylated. The clinical features can be nearly pathognomonic with facial weakness, scapular winging, and abdominal weakness with a positive Beevor sign. Diagnosis of late-onset or milder disease is often more challenging. Diseases mimicking the facioscapulohumeral muscular dystrophy phenotype should be recognized. We present 6 cases to illustrate both clinical and genetic diagnostic challenges in facioscapulohumeral muscular dystrophy and provide examples on how to navigate the different steps of genetic testing.

Keywords: DUX4; Epigenetic; Facioscapulohumeral muscular dystrophy; Hypomethylation; Muscle pathology; SMCHD1.

Publication types

Case Reports
Review

MeSH terms

Adult
Child, Preschool
Genetic Testing / methods*
Homeodomain Proteins / genetics*
Humans
Male
Middle Aged
Muscular Dystrophy, Facioscapulohumeral / diagnosis*
Muscular Dystrophy, Facioscapulohumeral / genetics*
Phenotype

Substances

DUX4L1 protein, human
Homeodomain Proteins