Preserved Forearm and Hand Muscles and Diaphragm with Mild Cardiac and Respiratory Involvement in a Patient with GNE Myopathy Harboring Homozygous Variants in GNE (c.1807G>C, p.V603L) over Four Decades after the Onset
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View abstract on PubMed
Summary
This summary is machine-generated.This study details a GNE myopathy case in a 67-year-old man with severe muscle weakness. Despite advanced GNE gene variants, distal upper extremities remained functional, with mild cardiac and respiratory issues noted.
Area Of Science
- Neurology
- Genetics
- Rare Diseases
Background
- GNE myopathy is a rare genetic neuromuscular disorder characterized by progressive muscle weakness.
- Mutations in the GNE gene are the underlying cause, leading to impaired protein function.
- The c.1807G>C, p.V603L homozygous variant is a common genotype associated with GNE myopathy.
Purpose Of The Study
- To report a case of GNE myopathy with a common homozygous GNE gene variant.
- To describe the clinical progression and phenotypic features, including late-stage muscle involvement and organ dysfunction.
- To highlight the preservation of distal upper extremities in this genotype.
Main Methods
- Case report of a 67-year-old Japanese male patient.
- Genetic analysis identifying homozygous GNE gene variants (c.1807G>C, p.V603L).
- Clinical assessment of muscle strength, cardiac function (ejection fraction), and respiratory function.
Main Results
- The patient presented with progressive weakness starting in the left foot at age 24, with severe functional limitation after 43 years.
- Homozygous c.1807G>C, p.V603L GNE gene variants were identified, correlating with severe muscle involvement.
- Distal upper extremities showed preservation of function until the end-stage.
- Mild cardiac dysfunction (ejection fraction 46.1%) and respiratory dysfunction with a preserved diaphragm were observed.
Conclusions
- The common GNE gene variant (c.1807G>C, p.V603L) can cause severe GNE myopathy with a characteristic pattern of muscle involvement.
- Preservation of distal upper extremities is a notable feature even in advanced stages.
- Cardiac and respiratory involvement, though typically mild, should be monitored in GNE myopathy patients.
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