Table 3. Risk of melanoma as estimated by mtDNA copy number.
| mtDNA index (relative copy number) | Number of cases (%) | Number of controls (%) | OR (95% CI)* |
|---|---|---|---|
| Continuous variable | 500 (100) | 500(100) | 1.45 (1.12–1.97) |
| Categorical variable | |||
| By mean in controls | |||
| <0.99 | 142 (28.4) | 249 (49.8) | 1.00 |
| ≥0.99 | 358 (71.6) | 251 (50.2) | 2.35 (1.78–3.14) |
| By quartile in controls | |||
| 1st | 71 (14.2) | 126 (25.2) | 1.00 |
| 2nd | 122 (24.4) | 125 (25.0) | 1.73 (1.16–2.98) |
| 3rd | 137 (27.4) | 123 (24.6) | 1.98 (1.24–3.21) |
| 4th | 170 (34.0) | 126 (25.2) | 2.39 (1.53–3.42) |
*ORs were adjusted by age.