Cardiac fibrosis, arrhythmia and sudden death in myotonic dystrophy type 1: Could TGF-ß1 improve the predictive accuracy of patients at risk, opening new therapeutic challenges?

Myotonic dystrophy type 1 (DM1, Steinert's syndrome) is an autosomal dominant disorder characterized by progressive skeletal muscle weakness, wasting, myotonia and non-muscular manifestations. It is caused by a trinucleotide cytosine–thymine–guanine (CTG) repeat expansion on chromosome 19 in the 3′ untranslated region of a serine–threonine protein kinase gene called DMPK (dystrophia myotonica protein kinase) [1]. As a consequence of the non-coding unstable CTG repeat expansion mutation, DM1 presents as an extremely wide clinical continuum ranging from antenatal to late adult forms, the complexity of the disease being reinforced by multisystemic involvement.