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Updated: Jun 24, 2026
06:37
Immunolabelling Myofiber Degeneration in Muscle Biopsies
Published on: December 5, 2019
[Amyloidosis in muscular dystrophy].
1Abteilung für Myologie, Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin und Max-Delbrück-Centrum Berlin, Lindenberger Weg 80, 13125, Berlin, Deutschland. miriam.carl@charite.de
Der Pathologe
|March 28, 2009
Summary
Mutations in the dysferlin (DYSF) gene cause muscular dystrophy. This study found amyloid deposits in patients with DYSF mutations, indicating a new aspect of this muscle disease.
Area of Science:
- Neurology
- Genetics
- Pathology
Background:
- Mutations in the dysferlin (DYSF) gene are linked to limb-girdle muscular dystrophy 2B (LGMD2B) and Miyoshi myopathy (MM).
- These genetic defects impact muscle membrane repair and integrity.
Purpose of the Study:
- To investigate the presence and characteristics of amyloid deposits in patients with suspected LGMD2B.
- To determine the relationship between DYSF mutations and observed amyloidosis.
Main Methods:
- Clinical examination of eight patients with suspected LGMD2B.
- Histochemical analysis of muscle biopsies.
- Genotyping to identify DYSF mutations.
Main Results:
- Amyloid deposits were identified in the sarcolemma and interstitium of muscle sections in four patients.
- All identified DYSF mutations associated with amyloidosis were located in the N-terminal region of the dysferlin protein.
- Dysferlin was confirmed as a component of these amyloid deposits.
Conclusions:
- Dysferlin-deficient muscular dystrophy represents the first muscular dystrophy associated with amyloidosis.
- The presence of amyloidosis must be considered in the development of therapeutic strategies for these conditions.
- The precise role of amyloid deposits in disease pathogenesis and potential extra-muscular involvement require further investigation.
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