Table 1. Characteristics of the included studies.

Study					Cases			Controls
	Diagnostic	Country				Male	Age		Male	Age	Ref
	criteria	/Area	Ethnicity	Investigated SNPs	N	(%)	(year)	N	(%)	(year)
Bocchio(2002)	DSM-IV	Italy	Caucasian	rs1800896, rs1800871, rs1800872	106	NA	NA	143	NA	NA	[20]
Yu(2004)	DSM-IIIR	China	Asian	rs1800896, rs1800871, rs1800872	341	54	42±16	334	52	42±16	[21]
Shirts(2006)	DSM-IV	USA	Caucasian	rs1800872	471	65	38±10	453	52	NA	[22]
Peng(2008)	DSM-IV	Taiwan	Asian	rs1800896, rs1800871, rs1800872	659	70	36±11	411	43	45±14	[23]
Ozbey(2009)	DSM-IV	Turkey	Asian	rs1800896, rs1800871, rs1800872	171	45	38±11	168	45	36±15	[24]
Almoguera(2011)	DSM-IV	Spain	Caucasian	rs1800896, rs1800871, rs1800872	241	63	NA	435	46	NA	[25]
PGC(CATIE)(2011)	DSM-IV	USA	Caucasian	rs1800872	395	NA	NA	391	NA	NA	[30]
Jun(2003)	DSM-IV	Korea	Asian	rs1800896	233	41	32	181	46	32	[26]
Jun(2002)	DSM-IV	Korea	Asian	rs1800871	141	NA	NA	146	NA	NA	[27]
Paul-Samojedny(2010)	DSM-IV	Poland	Caucasian	rs1800896	96	38	45±12	120	33	39±10	[28]
Lung(2011)	DSM-IV	Taiwan	Asian	rs1800896, rs1800871, rs1800872	233a	78	NA	433	44	45±14	[29]

PGC(CATIE): data from samples in Clinical Antipsychotic Trials of Intervention Effectiveness of Psychiatric Genomics Consortium; SNPs: single nucleotide polymorphisms; DSM: diagnosis and statistical manual of mental health disorders; NA:not available; ^aCases after excluding overlapping samples with study [23].