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Behavioral and Locomotor Measurements Using an Open Field Activity Monitoring System for Skeletal Muscle Diseases
Published on: September 29, 2014
Limb-girdle muscular dystrophy: diagnostic evaluation, frequency and clues to pathogenesis
Harriet P Lo1, Sandra T Cooper, Frances J Evesson
1Institute for Neuromuscular Research, The Children's Hospital at Westmead, Sydney, Australia.
Neuromuscular Disorders : NMD
|September 28, 2007
Summary
Limb-girdle muscular dystrophy (LGMD) subtypes were analyzed in Australian patients. Calpainopathies and dysferlinopathies are common, while LGMD2I is rare, differing from European frequencies.
Area of Science:
- Genetics
- Neurology
- Molecular Biology
Background:
- Limb-girdle muscular dystrophy (LGMD) encompasses a heterogeneous group of genetic disorders.
- Understanding the frequency of LGMD subtypes is crucial for diagnosis and research.
Purpose of the Study:
- To determine the frequency of LGMD subtypes in an Australian patient cohort.
- To identify potential novel LGMD disease genes.
Main Methods:
- Protein and DNA sequence analysis of 76 Australian muscular dystrophy patients.
- Comparative analysis of LGMD subtype frequencies with European populations.
Main Results:
- Calpainopathies (8%) and dysferlinopathies (5%) are the most frequent LGMD causes in Australia.
- LGMD2I (FKRP mutations) is rare (3%) in Australasia, unlike in Europe.
- A cohort of patients with excluded common disease genes was identified.
- Abnormal dysferlin localization, not correlating with regeneration, was observed in some patients, mimicking caveolinopathy.
Conclusions:
- LGMD subtype prevalence varies geographically.
- The identified patient cohort is a resource for discovering new LGMD genes.
- Abnormal dysferlin localization may indicate novel genetic defects, potentially involving membrane targeting pathways.
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