The first Clinical trial with DYN101 (UNITE-CNM) was early terminated. As a consequence, Dynacure decided to not perform this study.

This is a prospective, longitudinal study of the natural disease course intended to recruit approximately 60 patients with centronuclear myopathies (CNM) in Europe and the United States. The duration of the study, including the enrollment period, will be approximately 4 years. Data from the study will be used to characterize the natural disease course of CNM, to identify prognostic variables of the disease and to determine the best outcome measure(s) for the evaluation of future therapeutic approaches.

Inclusion Criteria:

• 1. Clinically symptomatic male or female subjects of all ages (newborns included) with a CNM resulting from a documented mutation in the MTM1 or DNM2 gene.
• 2. A written, signed and dated informed consent must be provided to participate in the study. For subjects <18 years, consent of parent(s)/legal guardian(s) is required; informed assent can be obtained from the child according to local regulations.
• 3. Willing and able to comply with all protocol requirements and procedures.

Exclusion Criteria:

• 1. Participation in any other interventional study. Participation in a previous study should be completed at least 4 weeks before the first study visit.
• 2. Currently undergoing or has undergone previous gene therapy or other therapy for CNM.
• 3. Current or past abuse of alcohol or recreational/narcotic drugs (with the exception of caffeine and nicotine), which in the investigator's opinion would compromise the subject's safety and/or compliance with the study procedures.
• 4. Current or relevant history of physical or psychiatric illness, that would make the subject unlikely to comply with the study procedures. (Note: Subjects in a wheelchair are not to be excluded).
• 5. Subject is mentally incapacitated, or parent(s)/legally-authorized representative are legally incapacitated or have limited legal capacity, or have lack of mental capacity to fully understand the protocol requirements and complete all study required procedures.

Patients of all ages (newborns included) with a CNM resulting from mutations in DNM2 or MTM1.