Neuropathy
Description
- Neuropathy is a condition affecting the nerves that can lead to pain, numbness, weakness or tingling in one or more parts of the body.
- There are over 100 genes known to cause hereditary neuropathies; four genes account for 90% of these diagnoses (PMP22, MFN2, MPZ, GJB1).
- Genetic testing is indicated for people with neuropathy with onset < 40 years, family history of neuropathy, foot deformities, or other symptoms of amyloidosis (autonomic dysfunction, cardiomyopathy, kidney disease, or glaucoma).
How often is a hereditary cause identified?
- The yield of genetic testing in people with neuropathy varies depending on the individual’s additional history/features.
- People who have slowly progressive distal motor weakness, and foot deformities, consistent with Charcot-Marie-Tooth disease (CMT) have a yield of genetic testing of 60-70%.
How does identifying a hereditary cause change a patient’s medical management?
- There are targeted therapies for some of the known genetic causes of neuropathy.
- For example, TTR-related amyloidosis and associated amyloid neuropathy has several FDA-approved treatments. Fabry disease has three approved therapies. Other targeted therapies for hereditary neuropathies are also under development.
How are these conditions inherited?
- Known genetic causes of hereditary neuropathies can be inherited in various inheritance patterns including autosomal dominant, autosomal recessive, or X-linked pattern, depending on the gene involved.
Where can I learn more about neuropathy?
References
- Dratch L, Azage M, Baldwin A, Johnson K, Paul RA, Bardakjian TM, Michon SC, Amado DA, Baer M, Deik AF, Elman LB, Gonzalez-Alegre P, Guo MH, Hamedani AG, Irwin DJ, Lasker A, Orthmann-Murphy J, Quinn C, Tropea TF, Scherer SS, Ellis CA. Genetic testing in adults with neurologic disorders: indications, approach, and clinical impacts. J Neurol. 2023 Oct 27. doi: 10.1007/s00415-023-12058-6. Epub ahead of print. PMID: 37891417.