[1] Univ Cape Town, Inst Infect Dis & Mol Med, UCT MRC Human Genet Res Unit, Div Human Genet,Fac Hlth Sci,Dept Pathol, ZA-7925 Cape Town, South Africa
[2] Univ Cape Town, Fac Hlth Sci, MRC Unit Risk & Resilience, ZA-7925 Cape Town, South Africa
[3] Groote Schuur Hosp, Dept Psychiat & Mental Hlth, ZA-7925 Cape Town, South Africa
[4] Univ Cape Town, Dept Psychiat & Mental Hlth, ZA-7925 Cape Town, South Africa
[5] Univ Southern Calif, Keck Sch Med, Mark & Mary Stevens Neuroimaging & Informat Inst, Imaging Genet Ctr, Los Angeles, CA 90292 USA