1. RTI International, Research Triangle Park, NC, USA
2. Parent Project Muscular Dystrophy, Hackensack, NJ, USA
3. Social and Behavioral Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
4. Seattle Children’s Hospital, Seattle, WA, USA
5. Cure SMA, Elk Grove Village, IL, USA
6. Kennedy Krieger Institute, Baltimore, MD, USA
7. Leiden University Medical Center, Leiden, The Netherlands