Congenital muscular dystrophies: What is new?

Congenital muscular dystrophies (CMDs) are a group of inherited conditions defined by muscle weakness occurring before the acquisition of ambulation, delayed motor milestones, and characterised by muscle dystrophic pathology. A large number of genes - at least 35- are responsible for CMD phenotypes, and it is therefore not surprising that CMDs comprise a wide spectrum of phenotypes, with variable involvement of cardiac/respiratory muscles, central nervous system, and ocular structures. The identification of several new genes over the past few years has further expanded both the clinical and the molecular spectrum underlying CMDs. Comprehensive gene panels allow to arrive at a final diagnosis in around 60% of cases, suggesting that both new genes, and unusual mutations of the currently known genes are likely to account for the remaining cases. The aim of this review is to present the most recent advances in this field. We will outline recent natural history studies that provide additional information on disease progression, discuss recently discovered genes and the current status of the most promising therapeutic options.