Okulopharyngeale Muskeldystrophie

Zusammenfassung

Die okulopharyngeale Muskeldystrophie (OPMD) ist eine autosomal-dominant vererbte Muskelerkrankung mit spätem Beginn, die klinisch durch eine Ptosis, Dysphagie und proximale Paresen gekennzeichnet ist. Die Erkrankung wird durch eine Trinukleotidvermehrung im Gen für das Poly-A-bindende Protein (PABPN1) verursacht. Hierdurch kommt es zu einer Verlängerung des Proteins um wenige Alanine, die zur Aggregation des Proteins führen. Diese Aggregate sind elektronenmikroskopisch als charakteristische intranukleäre Filamente nachweisbar. Der genaue pathogenetische Mechanismus, durch den es zum selektiven Befall der Muskelzellen und zur Ausbildung des typischen Phänotypes kommt, ist derzeit noch unklar.

Summary

Oculopharyngeal muscular dystrophy (OPMD) is a late onset myopathy with autosomal dominant inheritance. Clinical symptoms are eyelid drooping (ptosis), swallowing difficulties (dysphagia), and proximal limb weakness. Autosomal dominant OPMD is caused by an increased number of alanine coding trinukleotids in the PABPN1 gene leading to the expansion of a polyalanine stretch from 10 to 12-17 alanins in the N-terminal region of PABPN1. The expanded protein tends to form aggregates which are detectable as intranuclear filaments by electron microscopy. The definite pathogenetic mechanism leading to the selective damage of skeletal muscle cells and to the characteristic phenotype is presently unknown.

Schlüsselwörter

Okulopharyngeale Muskeldystrophie - OPMD - PABPN1 - PABP2

Keywords

Oculopharyngeal muscular dystrophy - OPMD - PABPN1 - PABP2

• Literatur

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