[1] Stanford Univ, Dept Genet, Sch Med, Stanford, CA 94305 USA
[2] Univ Calif San Francisco, Benioff Childrens Hosp, Oakland Res Inst, Childrens Hosp, San Francisco, CA 94143 USA
[3] Univ Calif San Diego, Dept Pediat, San Diego Sch Med, Div Genet, La Jolla, CA 92093 USA
[4] Stanford Hlth Care, Dept Neurol, Palo Alto, CA USA
[5] Stanford Univ, Dept Pediat, Div Med Genet, Med Ctr, Stanford, CA 94305 USA