Oculopharyngeal muscular dystrophy (PABPN1 expansions)
Structural diseases during infancy and adult age comprise the rest of muscular dystrophies: a group of hereditary diseases that affect the skeletal muscle, with the characteristic progressive degeneration of muscle fibers which causes loss of strength. This heterogeneous group of diseases continues to be characterized from the clinical and molecular point of view since decades ago, giving rise to increasingly more complex classifications based on genotype-phenotype correlation attempts.
At the moment, one of the most useful classifications in clinical therapy continues to be the predominant weakness pattern, that allows for the identification of phenotypes to guide the genetic studies. We have taken them as the basis to help make clinical decisions on choosing the best clinical panel for molecular diagnosis:
- Dystrophinopathies (DMD)
- Limb-girdle muscular dystrophy (both in the pelvic and shoulder regions)
- Emery-Dreifuss muscular dystrophy (characterized by a facio-scapulo-humeral distribution and early contractures, associated with cardiomyopathy)
- The distal myopathy group (with a pattern of predominant involvement at the distal level)
- Oculopharyngeal muscular dystrophy*
With the exception of oculopharyngeal muscular dystrophy* (whose main pathogenic mechanism is the expansion of triplets in the PABPN1 gene, a technique performed in our laboratory which must be specifically requested), the rest of the pathologies have a specific panel for their analysis. We have included an additional panel, chosen for particular characteristics on muscle biopsy, for the study of myofibrillar and protein aggregate myopathies.
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