[1] Kings Coll London, Inst Psychiat, MRC Ctr Neurodegenerat Res, Dept Neurosci P039, London SE5 8AF, England
[2] Massachusetts Gen Hosp, Day Neuromusc Lab, Charlestown, MA 02129 USA
[3] Univ Hong Kong, Dept Psychiat, Kowloon, Hong Kong, Peoples R China
[4] Univ Hong Kong, Genome Res Ctr, Kowloon, Hong Kong, Peoples R China
[5] Kings Coll London, Inst Psychiat, MRC Ctr Neurodegenerat Res, Dept Neurol, London SE5 8AF, England
[6] Univ Milan, Sch Med, IRCCS Ist Auxol Italiano, Dept Neurol & Lab Neurosci, I-20149 Milan, Italy
[7] Kings Coll London, Inst Psychiat, MRC Ctr Social Genet & Dev Psychiat, London SE5 8AF, England
[8] Umea Univ Hosp, Dept Neurol, SE-90185 Umea, Sweden