Congenital myopathies: Mechanisms and Therapies Skeletal muscles are composed of numerous cells called muscle fibres, the basic units for generating muscle strength and, ultimately, movement. These fibres feature a large number of proteins, known as contractile proteins. In normal muscle fibres, these proteins are well-organised allowing an optimal production of force. In certain muscle disorders termed congenital myopathies, these proteins are not encoded properly and mutant molecules are then expressed. Patients with these molecular defects suffer from deleterious muscle weakness. The mechanisms by which these mutant proteins induce skeletal muscle weakness are currently not known. In the present research project, we, therefore, investigate how the mutants affect (i) protein function; (ii) the generation of the force of muscle fibres; and (iii) the consequences on the cellular architecture. Deciphering these mechanisms allows us to design effective therapeutic interventions.