[1] Leiden Univ Med Ctr, Leiden, Netherlands
[2] Univ Nice, Ctr Reference Malad Neuromusculaires, Nice, France
[3] CNRS, F-06034 Nice, France
[4] Hosp Donostia, San Sebastian, Spain
[5] Fred Hutchinson Canc Res Ctr, Div Human Biol, Seattle, WA 98104 USA
[6] Radboud Univ Nijmegen Med Ctr, Nijmegen, Netherlands
[7] Univ Washington, Seattle, WA 98195 USA