Scientists reverse myotonia in a mouse model of myotonic dystrophy

Researchers from the University of Rochester Medical Center have been able to reverse the symptoms of myotonia in a mouse model for myotonic dystrophy. The results of this study have been published online today in the Journal of Clinical Investigation.

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Scientists reverse myotonia in a mouse model of myotonic dystrophy

Myotonic dystrophy is a progressive condition characterised by muscle weakness and wasting that mainly involves muscles in the lower legs, face, jaw and neck area. It represents the most common form of muscular dystrophy in adults and an estimated 6000 people currently live with the condition in the UK. One of the earliest symptoms is muscle stiffness described as “myotonia”. This affects several muscles, but particular the hands and is caused by inability to quickly relax the muscles after contraction.


Statement by Professor Darren Monckton from the University of Glasgow

Professor Darren Monckton from the University of Glasgow explains the research behind the findings:

“In this exciting paper the Thornton group have injected small morpholino molecules (chemical analogues of the genetic material DNA) into the muscles of two mouse models of myotonic dystrophy to correct the myotonia (muscle stiffness). In reversing the myotonia in mice, the study provides hope that myotonia may be similarly reversible in humans with myotonic dystrophy. In addition, the study provides direct proof that the myotonia observed in myotonic dystrophy is attributable to defects in the splicing (processing) of the chloride channel gene. The approach to determine this is very elegant and will prove a useful tool for determining the critical effects of the misplicing of other genes observed in myotonic dystrophy patients.

“However, the chloride channel gene is only one of probably many hundreds of genes that are misplaced in myotonic dystrophy and it will probably not be feasible to correct all these downstream defects simultaneously. Nonetheless, it may be possible to use the same type of technology to target an earlier step in the disease process thereby addressing more of the many symptoms observed in myotonic dystrophy.”


Statement by Director of Research at the Muscular Dystrophy Campaign, Dr Marita Pohlschmidt

Director of Research at the Muscular Dystrophy Campaign, Dr Marita Pohlschmidt, issued the following statement on the findings of this study:

“The fact that the findings show that myotonia can be reversed in a mouse model for myotonic dystrophy is exciting and reassuring, but we must be reminded that these experiments have been carried out in an animal model. We do however look forward to further research to see whether this kind of approach can be found to have an effect in people with the condition.”


Further information and links

The article entitled ‘Correction of ClC-1 splicing eliminates chloride channelopathy and myotonia in mouse models of myotonic dystrophy’ can be found online at the Journal of Clinical Investigation: content.the-jci.org/articles/view/33355

The Muscular Dystrophy Campaign currently supports research projects into myotonic dystrophy including work carried out by Professor Darren Monckton in Glasgow. For more information about this research project, visit:
www.muscular-dystrophy.org/research/grants/myotonic.html