Myotonic dystrophy type 2

Abstract

Myotonic dystrophy, type 2 (DM2) is an autosomal dominantdisorder caused by expansion of the CCTG repeats in the zinkfinger protein-9 gene (ZNF9). It has been clinically reported inthe middle 1990th. DM2 is less frequent than classic DM1,yet is relatively common, mostly in Europeans. Like DM1,DM2 is a multisystem disorder, and main distinctions fromDM1 are: relatively late onset, proximal character of myopathy,less severe myotonia, presence of myalgia, etc. Clinical featurescomplicate the diagnosis, and a number of cases cannot be identifiedon time. In the Research Centre for Medical Genetics theDNA diagnostics of DM2 is now available, and several caseshave been confirmed molecularly.

Keywords

• myotonic dystrophy type 2
• znf9 (cnbp1) gene
• cctg repeats
• proximal myotonic myopathy
• myalgia
• multisystem involvement