Table 2.

Main characteristics of studies included in this meta-analysis.

References	Country (Ethnicity)	Sample size		Genotype distribution (Case)					Genotype distribution (Control)					Source of control	Genotyping method	HWE
		Cases	Controls	AA	AG	GG	A	G	AA	AG	GG	A	G
Sugawara et al., 2003	Japan (Asian)	75	31	48	27	0	123	27	21	10	0	52	10	PB	PCR	Yes
Huang et al., 2006	China (Asian)	113	113	36	62	1	134	64	14	95	1	123	97	HB	PCR-RFLP	No
Joseph et al., 2006	India (Caucasian)	147	165	91	45	11	227	67	136	26	3	298	32	PB	PCR-RFLP	Yes
Gutman et al., 2009	Israel (Caucasian)	43	123	29	14	0	72	14	85	31	5	201	41	PB	PCR-RFLP	Yes
Zhang, 2009	China (Asian)	50	30	14	26	10	54	34	17	7	6	41	19	HB	PCR-RFLP	No
Shi et al., 2011	China (Asian)	176	112	34	121	21	189	163	32	76	4	140	84	PB	PCR-RFLP	No
Ding et al., 2011	China (Asian)	280	280	72	129	79	273	287	83	100	97	266	294	PB	PCR-RFLP	No
Zhang, 2011	China (Asian)	32	114	14	13	3	41	19	34	51	17	119	85	HB	PCR-RFLP	Yes
Abbas et al., 2014	India (Caucasian)	200	208	110	84	6	304	96	114	65	2	347	69	PB	PCR-RFLP	No
Roszak et al., 2014	Poland (Caucasian)	456	495	415	41	0	871	82	466	29	0	961	29	PB	PCR-RFLP	Yes
Li et al., 2016	China (Asian)	360	368	199	141	20	539	181	217	135	16	569	167	PB	PCR-Taqman	Yes

PCR-RFLP, polymerase chain reaction-restriction fragment length polymorphism; HWE, Hardy-Weinberg equilibrium.