Table 3. Results from meta-analysis of −137 G>C and cancer risk.

		CC vs. GG		GC vs. GG			GC/CC vs. GG		CC vs. GG/GC
	N	OR	Ph	OR		Ph	OR	Ph	OR	Ph
Total	21	1.09(0.78, 1.51)	<0.001	1.15(0.94, 1.40)		<0.001	1.13(0.92, 1.39)	<0.001	1.02(0.76, 1.37)	0.005
Cancer Types
GC	4	0.80(0.44, 1.47)	0.301	1.17(0.73, 1.87)		0.032	1.11(0.72, 1.73)	0.037	0.75(0.41, 1.38)	0.274
NC	4	2.10(1.34, 3.29)*	0.538	1.48(1.18, 1.86)*		0.512	1.57(1.26, 1.96)*	0.373	1.82(1.17, 2.84)*	0.611
GUC	4	1.10(0.45, 2.72)	0.065	1.20(0.72, 2.00)		<0.001	1.19(0.70, 2.04)	<0.001	1.04(0.52, 2.09)	0.197
GIC	5	0.96(0.41, 2.23)	0.001	1.24(0.87, 1.76)		0.007	1.18(0.78, 1.80)	<0.001	0.90(0.43, 1.88)	0.005
Others	4	0.73(0.44, 1.21)	0.310	0.68(0.30, 1.51)		<0.001	0.71(0.37, 1.36)	<0.001	0.80(0.45, 1.41)	0.197
Ethnicities
Asian	15	1.13(0.72, 1.78)	<0.001	1.35(1.12, 1.64)*	0.001		1.31(1.05, 1.64)*	<0.001	1.00(0.66, 1.51)	0.001
Caucasian	4	0.91(0.55, 1.51)	0.296	0.64(0.33, 1.23)	<0.001		0.70(0.39, 1.24)	<0.001	0.99(0.63, 1.54)	0.360
African	1	1.28(0.57, 2.86)	N/A	1.19(0.75, 1.87)	N/A		1.20(0.78, 1.86)	N/A	1.18(0.54, 2.56)	N/A
Mixed	1	0.85(0.31, 2.35)	N/A	0.74(0.48, 1.15)	N/A		0.75(0.49, 1.14)	N/A	0.93(0.34, 2.56)	N/A
Source of Controls
PB	12	0.85(0.55, 1.33)	0.005	0.90(0.70, 1.15)	<0.001		0.88(0.69, 1.13)	<0.001	0.87(0.58, 1.31)	0.013
HB	9	1.49(0.97, 2.27)	0.078	1.62(1.34, 1.96)*	0.131		1.59(1.29, 1.97)*	0.033	1.26(0.85, 1.86)	0.129
Sample Size
Large a	4	1.30(0.51, 3.27)	0.019	1.14(0.73, 1.80)	<0.001		1.16(0.70, 1.92)	<0.001	1.27(0.60, 2.70)	0.073
Small b	17	1.03(0.73, 1.46)	0.003	1.14(0.91, 1.45)	<0.001		1.12(0.89, 1.42)	<0.001	0.97(0.70, 1.33)	0.016

GC: Gynecological cancer; NC: Nasopharyngeal carcinoma; GUC: Genitourinary system cancer; GIC: Gastrointestinal cancer; N: number of studies included; OR: odds ratio; P_h: p value for heterogeneity;

^*OR with statistical significance;

^astudies with more than 500 participants;

^bstudies with less than 500 participants;