Humpath.com - Human pathology

Home > E. Pathology by systems > Locomotory system > Muscles > myotonic dystrophy

myotonic dystrophy

Monday 22 September 2003

Myotonic dystrophy (DM), the most common form of muscular dystrophy in adults, is a clinically and genetically heterogeneous neuromuscular disorder. DM is characterized by autosomal dominant inheritance, muscular dystrophy, myotonia, and multisystem involvement.

Etiology

- Type 1 DM (DM1) is caused by a (CTG)(n) expansion in the 3’ untranslated region of the DMPK gene in 19q13.3.
- Type 2 DM (DM2) but without the DM1 mutation, showed linkage to the 3q21 region and were recently shown to segregate a (CCTG)(n) expansion mutation in intron 1 of ZNF9.
- Type 3 DM (DM3) 3q21

References

- Harris S, Moncrieff C, Johnson K. Myotonic dystrophy: will the real gene please step forward! Hum Mol Genet. 1996;5 Spec No:1417-23. PMID: 8875246

- Ozawa E, Yoshida M, Suzuki A, Mizuno Y, Hagiwara Y, Noguchi S. Dystrophin-associated proteins in muscular dystrophy. Hum Mol Genet. 1995;4 Spec No:1711-6. PMID: 8541869