Table 6.
Comparison between DNA samples, extracted from whole blood at arrival to the laboratory, and stored 4 years at −80°C and DNA samples extracted from frozen whole blood. After 4 years, DNA was extracted from the frozen whole blood and compared with DNA frozen for 4 years. The results from two-sided paired t-test showed no significant difference between dTG, dC, and dTG/dC ratio values between day 0 and 4 years. %RE = (mean−mean day zero)/mean day zero × 100
| Day 0 | Four years | |||||
|---|---|---|---|---|---|---|
| dTG nmol/L |
dC µmol/L |
Ratio dTG/dC ×10−3 | dTG nmol/L |
dC µmol/L |
Ratio dTG/dC ×10−3 |
|
| Patient | ||||||
| 1A | 0.09 | 1.0 | 0.09 | 0.10 | 0.9 | 0.11 |
| 2A | 0.56 | 1.1 | 0.52 | 0.50 | 1.0 | 0.51 |
| 3A | 0.38 | 0.8 | 0.47 | 0.39 | 0.8 | 0.49 |
| 4A | 1.26 | 0.7 | 1.78 | 1.47 | 0.8 | 1.89 |
| 5A | 0.73 | 0.9 | 0.77 | 1.13 | 1.3 | 0.90 |
| 6A | 1.69 | 0.7 | 2.38 | 1.88 | 0.7 | 2.58 |
| 7A | 0.93 | 1.4 | 0.68 | 0.77 | 1.2 | 0.65 |
| 8A | 0.56 | 0.7 | 0.82 | 0.54 | 0.7 | 0.82 |
| 9A | 1.24 | 1.0 | 1.20 | 1.20 | 1.0 | 1.26 |
| Mean | 0.83 | 0.9 | 0.97 | 0.89 | 0.9 | 1.02 |
| %RE | 7.3 | −1.2 | 5.7 | |||
Abbreviations: dTG, 2′-deoxythioguanosine; dC, 2′-deoxycytidine