Table 2. Association between copy number of the GSTM1 and GSTT1 genes and risk of prostate cancer.
| Cases | Controls | Crude OR (95% CI) | Adjusted OR (95% CI)a | |
| GSTM1 copy number | n = 629 (%) | n = 622 (%) | ||
| 0 | 159 (25.3) | 197 (31.7) | 1.0 | 1.0 |
| 1 | 317 (50.4) | 284 (45.7) | 1.38 (1.06–1.80) | 1.37 (1.04–1.82) |
| 2 | 142 (22.6) | 137 (22.0) | 1.28 (0.94–1.76) | 1.28 (0.84–1.62) |
| ≥3 | 11 (1.7) | 4 (0.6) | 3.40 (1.06–10.9) | 2.55 (0.78–8.39) |
| P trend | 0.03 | 0.17 | ||
| Non-Carrier | 159 (25.3) | 197 (31.7) | 1.0 | 1.0 |
| Carrier | 470 (74.7) | 425 (68.3) | 1.09 (0.78–1.51) | 1.31 (1.01–1.71) |
| GSTT1 copy number | ||||
| 0 | 153 (24.3) | 192 (30.9) | 1.0 | 1.0 |
| 1 | 280 (44.5) | 284 (45.7) | 1.24 (0.95–1.62) | 1.26 (0.94–1.68) |
| 2 | 173 (27.5) | 141 (22.7) | 1.54 (1.13–2.09) | 1.55 (1.11–2.16) |
| ≥3 | 23 (3.7) | 5 (0.8) | 5.77 (2.14–15.5) | 4.89 (1.71–13.99) |
| P trend | 0.0002 | 0.0006 | ||
| Non-Carrier | 153 (24.3) | 192 (30.9) | 1.0 | 1.0 |
| Carrier | 476 (75.7) | 430 (69.1) | 1.38 (1.08–1.77) | 1.40 (1.07–1.83) |
| Sum of GSTM1 / GSTT1 copy numbers | ||||
| 0b | 33 (5.2) | 45 (7.2) | 1.0 | 1.0 |
| 1c | 160 (25.4) | 188 (30.3) | 1.16 (0.71–1.91) | 1.56 (0.88–2.76) |
| 2d | 219 (34.9) | 236 (37.9) | 1.26 (0.78–2.06) | 1.71 (0.98–2.99) |
| 3e | 143 (22.7) | 114 (18.3) | 1.71 (1.02–2.85) | 2.18 (1.21–3.91) |
| 4f | 61 (9.7) | 36 (5.8) | 2.31 (1.25–4.25) | 3.24 (1.63–6.46) |
| ≥5g | 13 (2.1) | 3 (0.5) | 5.90 (1.55–22.4) | 5.77 (1.40–23.8) |
| P trend | <0.0001 | <0.0001 | ||
| Non-Carrier | 33 (5.2) | 45 (7.2) | 1.0 | 1.0 |
| Carrier | 596 (94.8) | 577 (92.8) | 1.41 (0.89–2.23) | 1.88 (1.11–3.21) |
a
Unconditional logistic regression adjusted for age and education for GSTM1; for age and family history of prostate cancer for GSTT1; for age and PSA screening history for the sum of GSTM1 and GSTT1 alleles.
b
GSTM1 0 and GSTT1 0;
c
GSTM1 0 and GSTT1 1 or GSTM1 1 and GSTT1 0;
d
GSTM1 1 and GSTT1 1 or GSTM1 0 and GSTT1 2 or GSTM1 2 and GSTT1 0;
e
GSTM1 2 and GSTT1 1 or GSTM1 1 and GSTT1 2 or GSTM1 3 and GSTT1 0 or GSTM1 0 and GSTT1 3;
f
GSTM1 2 and GSTT1 2 or GSTM1 3 and GSTT1 1 or GSTM1 1 and GSTT1 3 or GSTM1 4 and GSTT1 0 or GSTM1 0 and GSTT1 4;
g
GSTM1 3 and GSTT1 2 or GSTM1 2 and GSTT1 3 or GSTM1 4 and GSTT1 3 or GSTM1 4 and GSTT1 1 or GSTM1 1 and GSTT1 4 or GSTM1 4 and GSTT1 2.