. 2012 Mar 5;7(3):e32159. doi: 10.1371/journal.pone.0032159

Table 1. Main characteristics of all studies included in the meta-analysis.

Study	Ethnicity	Genotyping method	Source of control	P_HWE	Frequency of G allele	Cases/Controls	No. of cases			No. of controls
							GG	GA	AA	GG	GA	AA
Tanabe 2008a¹⁶	Mixed	PCR-RFLP	HB	0.19	0.001	59/148	23	27	9	32	65	51
Tanabe 2008b¹⁶	Caucasian	PCR-RFLP	HB	0.99	0.04	44/77	15	17	12	12	37	28
Abu 2011¹⁷	Mixed	allele-specific PCR	HB	0.08	0.08	66/750	24	25	17	180	350	220
Chen 2011¹⁸	Chinese-Han	PCR-RFLP	HB and PB	0.56	0.11	120/240	62	51	7	106	110	24
Li 2009¹⁹	Chinese-Han	PCR-RFLP	HB and PB	0.94	0.12	186/338	96	82	8	161	145	32
Qi 2009²⁰	Chinese-Han	PCR-RFLP	HB and PB	0.75	0.55	215/380	102	98	15	182	160	38
Wang 2009a²¹	Chinese^*	PCR-RFLP	HB	0.37	0.06	397/480	200	163	34	209	222	49
Wang 2009b²¹	Chinese-Han	PCR-RFLP	HB	0.53	0.06	217/200	125	76	16	94	89	17

Abbreviations: PCR-RFLP, polymerase chain reaction-restriction fragment length polymorphism; PB, population-based; HB, hospital-based; P_HWE, Hardy-Weinberg equilibrium of controls.

Included multiple ethnicities in China.