Table 3.

Characteristics of the studies included in the meta-analysis.

Authors	Year	Region	Source of controls	Genotyping method	Cases					Controls					P value⁎
GG	AG	AA	G	A	GG	AG	AA	G	A
Current study	–	NC	Community	PCR–LDR	934	771	98	2639	967	4163	2961	540	11,287	4041	0.67
Ng et al.	2007	SC	Community	MALDI-TOF	–	–	–	676	190	–	–	–	599	239	–
Lin et al.	2010	SC	Community	ABI SNaPshot	–	–	–	2174	884	–	–	–	2023	855	–
Luo et al.	2009	NC	Hospital	ABI SNaPshot	250	184	34	684	252	257	182	29	696	240	0.67
Ma et al.	2009	SC	Hospital	PCR-PFLP	93	123	43	309	209	67	106	31	240	168	0.30
Qiao et al.	2012	NC	Hospital	PCR–LDR	382	261	53	1025	367	292	235	30	819	295	0.05
Zhang et al.	2008	SC	Hospital	Taqman	253	210	31	716	272	235	153	34	623	221	0.20
Zheng et al.	2012	SC	Hospital	MALDI-TOF	128	84	15	340	114	80	58	14	218	86	0.46
Zhu et al.	2010	SC	Hospital	Taqman	14	127	159	155	445	10	102	188	122	478	0.39
Miyake et al.	2008	Japan	Community	Taqman	1316	724	93	3356	910	1112	612	100	2836	812	0.19

NC, northern China; SC, southern China.

^⁎P value for Hardy–Weinberg equilibrium.