[1] McGill Univ, Ctr Res Neurosci, Montreal, PQ H3A 2T5, Canada
[2] McGill Univ, Dept Neurol & Neurosurg, Montreal, PQ, Canada
[3] Montreal Childrens Hosp, Div Med Genet, F Clarke Fraser Clin Genet Unit, Montreal, PQ H3H 1P3, Canada
[4] McGill Univ, Dept Human Genet, Montreal, PQ, Canada
[5] Amer Univ Beirut, Ctr Med, Dept Dermatol, Beirut, Lebanon