Neuromuscular Genetics

What are Neuromuscular Disorders?

Neuromuscular Disorders (NMD) are a group of conditions characterized by progressive muscle degeneration and weakness that most often have a genetic cause. Most of these genetic variants display autosomal recessive, autosomal dominant, or X-linked inheritance.

What are some Neuromuscular Disorders with Genetic Causes?

  • Duchenne Muscular Dystrophy (DMD)

  • Duchenne-related Dilated Cardiomyopathy (DCM)

  • Becker Muscular Dystrophy (BMD)

Learn more about The Dystrophin Gene and Associated Diseases here.

Learn more about DMD/BMD Gene Therapies here.

  • Charcot-Marie Tooth (CMT)

  • Spinal Muscular Atrophy (SMA)

  • Limb-Girdle Muscular Dystrophies (LGMD)

  • Spastic Paraplegia (SPG)

  • Motor Neuron Diseases (ex. ALS)

  • Any congenital muscular dystrophies and myopathies (CMD)

Duchenne Muscular Dystrophy (DMD) and Becker Muscular Dystrophy (BMD)

DMD and BMD are both genetic neuromuscular disorders classified as X-linked dystrophinopathies, where changes in the dystrophin gene cause progressive muscle weakness and loss of mobility. 

Dystrophin is a protein responsible for connecting muscle fibers to the extracellular matrix (7). The extracellular matrix is a complex network of proteins and other molecules that work to structurally support the body as well as regulating other aspects of cellular growth and behavior (8). DMD is the longest human gene, which makes it susceptible to random genetic changes that occur within important regions of the gene. Generally, patients with DMD do not produce any detectable functional dystrophin, while those with genetic changes associated with BMD generally have a shortened or reduced amount of the functional or detectable dystrophin protein (32). 

DMD affects around 4.8 per 100,000 individuals globally and is often associated with respiratory or cardiac complications, which often require a great deal of assistance and 24/7 care support (7, 34).

  • ~60% of DMD cases are due to deletions (7)

  • ~6% of DMD cases are due to duplications (7)

  • Remaining DMD cases are most likely caused by changes to the order of the DNA sequence (7)

BMD affects an estimated 1.6 per 100,000 individuals globally (34). It presents very similarly to DMD and sometimes cannot be differentiated, but often, BMD may have reduced severity of symptoms and possibly a later age of onset (32).

Who can benefit from genetic counseling for Neuromuscular Disorders?

  • Individuals with a personal or family history of seizures, brain tumors, neurodegenerative diseases, or neuromuscular disorders

  • Individuals experiencing abnormal muscle weakness, fatigue, or pain

  • Individuals seeking guidance on their options for gene therapies for their current neurological or neuromuscular condition (including cancers of the nervous system)

How Can Clover Genetics Help?

  • Identify genetic testing, support, and care programs as needed

  • Facilitate the identification of treatments or clinical trials

  • Empower patients to identify and manage their care needs

  • Facilitate counseling for affected, or at risk family members