Table 3. Main results of the pooled data in the present meta-analysis.

	No. (cases/controls)	GG vs TT			(GG+GT) vs TT			GG vs (GT+TT)
		OR (95%CI)	P	P (Q-test)	OR (95%CI)	P	P (Q-test)	OR (95%CI)	P	P (Q-test)
Total	7196/8456	1.14 (0.95–1.37)	0.164	0.001	1.05 (0.92–1.19)	0.502	0.001	1.12 (0.99–1.27)	0.084	0.035
Ethnicity
Asian	2905/3569	1.23 (0.91–1.66)	0.181	0.004	1.18 (0.96–1.46)	0.108	0.036	1.14 (0.93–1.40)	0.206	0.024
Caucasian	4158/4632	1.05 (0.86–1.27)	0.654	0.106	0.96 (0.86–1.07)	0.434	0.218	1.08 (0.92–1.27)	0.368	0.183
African	133/255	0.73 (0.14–3.83)	0.711	–	0.77 (0.45–1.34)	0.360	–	0.76 (0.15–3.99)	0.749	–
Smoking status
Ever smoking	3309/3056	1.25 (0.78–1.99)	0.354	0.000	1.08 (0.77–1.51)	0.652	0.000	1.21 (0.90–1.62)	0.205	0.004
Never smoking	815/1481	1.76 (1.36–2.29)	0.000	0.926	1.48 (1.22–1.81)	0.000	0.501	1.37 (1.11–1.69)	0.004	0.994
Histological types
AC	2355/5802	1.24 (0.90–1.70)	0.188	0.003	1.07 (0.88–1.31)	0.503	0.016	1.21 (0.96–1.52)	0.102	0.023
SQCC	1770/4833	1.12 (0.83–1.52)	0.456	0.012	1.03 (0.80–1.34)	0.814	0.003	1.13 (0.96–1.33)	0.150	0.242
Source of control
HB	5116/5330	1.06 (0.88–1.27)	0.549	0.053	1.00 (0.87–1.16)	0.993	0.026	1.06 (0.94–1.18)	0.336	0.310
PB	2080/3126	1.36 (0.92–2.01)	0.121	0.013	1.15 (0.88–1.49)	0.301	0.014	1.28 (0.96–1.71)	0.090	0.055
Gender
Male	2253/2760	0.99 (0.75–1.31)	0.951	0.064	0.94 (0.79–1.13)	0.533	0.091	1.02 (0.81–1.29)	0.843	0.098
Female	1740/2033	1.28 (0.95–1.73)	0.098	0.165	1.01 (0.86–1.18)	0.926	0.313	1.29 (1.04–1.59)	0.019	0.336

AC: adenocarcinoma; SQCC: squamous cell carcinoma; PB: population-based; HB: hospital-based.