[1] Kennedy Krieger Inst, Dept Neurol & Dev Med, Baltimore, MD 21205 USA
[2] Johns Hopkins Univ, Dept Neurosci, Baltimore, MD USA
[3] Johns Hopkins Sch Med, Dept Dermatol, Baltimore, MD USA
[4] Johns Hopkins Sch Med, Dept Neurol, Baltimore, MD USA
[5] Johns Hopkins Sch Med, Dept Pediat, Baltimore, MD USA