Myotone Dystrophien – Phänotypen, Pathogenese, Diagnostik und Therapie

B. G. H. Schoser

doi:10.1055/s-0038-1626835

Nervenheilkunde, Table of Contents

Nervenheilkunde 2007; 26(01/02): 74-78
DOI: 10.1055/s-0038-1626835

Original- und Übersichtsarbeiten - Original and Review Articles

Schattauer GmbH

Myotone Dystrophien – Phänotypen, Pathogenese, Diagnostik und Therapie

Zusammenfassung eines Minisymposiums im Rahmen der Neurowoche 2006, MannheimMyotonic dystrophies – phenotypes, pathogenesis, diagnostics and therapyProceedings of a symposium at the German Neurowoche 2006, Mannheim, Germany

B. G. H. Schoser

¹Neurologische Klinik, Ludwig-Maximilians-Universität München (Leitender Arzt: Prof. Dr. D. Pongratz)

› Author Affiliations

Abstract

Zusammenfassung

Zwei Formen der myotonen Dystrophie (DM1, DM2) sind bisher beschrieben. 1992 konnte als genetische Ursache der DM1 ein abnorm expandiertes CTG-Triplettrepeat im 3´-UTR (untranslated region) des Dystrophia myotonica Proteinkinasegens (DMPK) auf Chromosom 19 gefunden werden. Die DM2 wurde 1994 durch Ricker und Thornton beschrieben und 2001 konnte ein abnorm expandiertes Tetranukleotid CCTG-Repeat im Intron 1 des Zinkfinger-9-Gens (ZNF-9) auf Chromosom 3q als kausal identifiziert werden. Multisystemische Symptome betreffen Skelettmuskulatur, Gehirn, Auge, Herz und Endokrinum. Der heterogenen Ätiologie mit zwei genetischen Loci liegt pathogenetisch eine RNA-Prozessierungsstörung mit alternativem Spleißen von organspezifischen Genen zugrunde (sogenanntes Konzept der Spleißeopathie).

Unser Symposium umfasste Beiträge zu aktuellen Aspekten der Klinik, Diagnostik, Bildgebung, Geburtshilfe und Schwangerschaft, molekularen RNA-Pathogenese sowie symptomatischen und molekularen Therapieoptionen.

Summary

Myotonic dystrophies cover at least two clinical and molecular distinct forms, the classic (Steinert’s disease; DM1) and the new type (Ricker’s disease, DM2). In 1992, the mutation causing DM1 was identified as a CTG repeat in the DMPK gene on chromosome 19q, and in 2001 the mutation causing DM2 was identified as a CCTG repeat in the ZNF-9 gene on chromosome 3q. The pathogenesis of both forms seems to be based ona gain-of-function RNA mechanism, as multisystemic features are caused by alternative splicing of tissue specific genes. Thus, recently the term spliceopathy was introduced. Our symposium focused on multisystemic clinical features, new diagnostic techniques, new aspects of the molecular pathogenesis and symptomatic treatment options.

Schlüsselwörter

DM1 - DM2 - myotone Dystrophien - Repeat-Erkrankung - Therapie

Keywords

DM1 - DM2 - myotonic dystrophy - repeat disorder - treatment

Full Text

References

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