Table 2. Results of meta-analysis for 3801T>C polymorphism of CYP1A1 and idiopathic male infertility risk.
| Study group | No. of study | sample size (cases/controls) | Allele model (C vs. T) | Homozygous model (CC vs. TT) | Heterozygous model (TC vs. TT) | Dominant model (CC+TC vs. TT) | Recessive model (CC vs. TC+TT) | |||||
| OR (95% CI) | P h | OR (95% CI) | P h | OR (95% CI) | P h | OR (95% CI) | P h | OR (95% CI) | P h | |||
| All | 6 | 1060/1225 | 1.36(1.01,1.83) | <0.001 | 2.18(1.15,4.12) | 0.003 | 1.25(0.95,1.65) | 0.051 | 1.38(0.99,1.92) | 0.003 | 1.86(1.09,3.20) | 0.013 |
| Asian | 3 | 501/568 | 1.58(0.93,2.67) | <0.001 | 2.35(0.90,6.16) | 0.003 | 1.48(0.91,2.40) | 0.040 | 1.67(0.92,3.05) | 0.004 | 1.90(0.89,4.05) | 0.015 |
| Caucasian | 3 | 559/657 | 1.18(0.81,1.72) | 0.031 | 2.02(0.66,6.20) | 0.042 | 1.13(0.89,1.43) F | 0.353 | 1.16(0.79,1.71) | 0.086 | 1.89(0.64,5.58) | 0.046 |
| High quality | 4 | 751/883 | 1.19(0.93,1.53) | 0.073 | 1.75(0.89,3.43) | 0.028 | 1.15(0.92,1.42) F | 0.339 | 1.22(0.99,1.50) F | 0.170 | 1.58(0.83,3.00) | 0.084 |
| Low quality | 2 | 309/342 | 1.85(0.74,4.61) | <0.001 | 3.28(0.58,18.56) | 0.002 | 1.64(0.68,3.96) | 0.013 | 1.95(0.68,5.59) | 0.002 | 2.56(0.67,9.78) | 0.009 |
| Sample size >400 | 4 | 805/885 | 1.21(0.95,1.53) | 0.081 | 1.79(0.97,3.32) | 0.100 | 1.13(0.91,1.39) F | 0.330 | 1.20(0.92,1.56) F | 0.167 | 1.55(0.98,2.19) F | 0.107 |
| Sample size <400 | 2 | 255/340 | 1.81(0.69,4.73) | <0.001 | 3.09(0.47,20.14) | <0.001 | 1.71(0.77,3.82) | 0.027 | 1.86(0.59,55.89) | 0.001 | 2.37(0.52,10.89) | 0.005 |
Ph P value for heterogeneity based on Q test. All pooled ORs were derived from random-effects model except for cells marked with (fixed F).