[1] Univ Newcastle Upon Tyne, Inst Human Genet, Int Ctr Life, Newcastle Upon Tyne NE1 3BZ, Tyne & Wear, England
[2] Univ Hosp Essen, Dept Paediat & Paediat Neurol, Essen, Germany
[3] Univ Paris 06, Grp Hosp Pitie Salpetriere, Inst Myol, F-75252 Paris 05, France
[4] Withington Hosp, Dept Neurol, Manchester M20 8LR, Lancs, England
[5] John Radcliffe Hosp, Dept Clin Neurol, Oxford OX3 9DU, England
[6] Univ Med Ctr Utrecht, Rudolf Magnus Inst Neurosci, Dept Neurol, Utrecht, Netherlands
[7] Cairo Univ, Kasr Al Aini Fac Med, Dept Neurol, Cairo, Egypt