[1] Columbia Univ, Dept Psychiat, NYSPI, Unit 24, New York, NY 10032 USA
[2] Columbia Univ, Dept Biostat, Div Stat Genet, New York, NY USA
[3] New York State Psychiat Inst & Hosp, Div Clin Genet Epidemiol, New York, NY 10032 USA
[4] Columbia Univ, Genome Ctr, New York, NY USA
[5] Univ Iowa, Coll Publ Hlth, Dept Biostat, Div Stat Genet, Iowa City, IA USA
[6] Univ Iowa, Coll Med, Dept Psychiat, Iowa City, IA 52242 USA