[1] Univ Copenhagen, Neuromuscular Res Unit, DK-2100 Copenhagen, Denmark
[2] Univ Copenhagen, Rigshosp, Dept Neurol 2081, DK-2100 Copenhagen, Denmark
[3] Univ Copenhagen, Rigshosp, Dept Neurophysiol 3061, DK-2100 Copenhagen, Denmark
[4] Univ Copenhagen, Rigshosp, Dept Clin Genet 4062, DK-2100 Copenhagen, Denmark