Table 2.

Results of meta-analysis of polymorphisms and risk for colorectal cancer in group A.

	Study numbers	Cumulative cases	Cumulative controls	Test of heterogeneity		Statistical method	OR	95% CI	Significance P
				Q	P
GSTM1 deletion	18	5455	6853	31.1	<0.05	Random	1.08	0.96-1.20	>0.20
GSTT1 deletion	11	1348	1792	29.79	<0.001	Random	1.42b	1.21-1.66	<0.001
GSTP1 lle105Val	4	612	755	4.06	0.2	Fixed	1.09	0.87-1.37	>0.30
NAT1*10	3	520	433	5.43	0.10-0.20	Fixed	1.25	0.96-1.63	>0.10
NAT2-rapid acetylator p&g	18	6741	8015	22.86	0.20-0.30	Fixed	1.08a	1.00-1.16	<0.05
NAT2-rapid acetylator p	8	2182	2861	14.24	0.10-0.20	Fixed	1.15a	1.02-1.31	<0.05
NAT2-rapid acetylator g	10	4559	5154	7.71	>0.50	Fixed	1.05	0.94-1.14	>0.20
CYP1A1 Lle462Val	2	235	280	1.77	>0.30	Fixed	1.26	0.77-2.08	0.05-0.1
CYP1A1 MspI*C	2	234	250	8.36	<0.02	Random	1.3	0.82-2.06	>0.30
METHFR C677T	4	1949	3099	3.11	0.30-0.50	Fixed	0.83	0.68-1.01	>0.10
MTR A2759G	3	613	1 189	0	0.9	Fixed	0.6	0.28-1.29	0.10-0.20

Fixed: Fixed-effect model, Random: Random-effects model.

^aP<0.05,

^bP<0.01.