Table 3.
Effect of DNA Pretreatment on Background Error in KRAS and GNAS Hotspot Mutations in Plasma Samples
| Case | Study group | DNA treatment | Mutation hotspot dNGS score |
|||||
|---|---|---|---|---|---|---|---|---|
| G12A G12C | G12D G12V | G12R G12S | G13D R201C | R201H | Overall dNGS score | |||
| 2 | Healthy control | None UNG |
0 0 0 0 |
1 0 0 0 |
0 0 0 0 |
0 0 0 0 |
0 1 |
1 1 |
| 3 | Healthy control | None UNG |
0 0 0 0 |
0 1 1 0 |
0 3 0 0 |
2 5 0 2 |
2 0 |
13 3 |
| 4 | Healthy control | None UNG |
0 0 0 0 |
0 0 1 0 |
0 0 0 0 |
0 0 0 1 |
1 0 |
1 2 |
| 17 | Disease control | None PreCR + UNG |
0 0 0 0 |
3 5 1 1 |
0 0 0 0 |
1 0 0 1 |
0 0 |
9 3 |
| 18 | Disease control | None PreCR + UNG |
0 0 0 0 |
0 3 0 2 |
0 0 0 0 |
1 2 0 0 |
0 0 |
6 2 |
| 33 | Disease control | None PreCR + UNG |
0 0 0 0 |
0 1 0 1 |
0 0 0 1 |
0 0 0 0 |
1 0 |
2 2 |
| 68 | PDAC | None PreCR + UNG |
0 0 0 0 |
0 2 0 0 |
0 0 0 0 |
0 0 0 0 |
0 0 |
2 0 |
| 121 | PDAC | None PreCR + UNG |
0 0 0 0 |
2 3 0 1 |
0 0 0 0 |
0 0 0 0 |
1 1 |
6 2 |
The mean number of positive wells calculated for untreated samples was 5 compared with 1.9 for pretreated DNA samples (P = 0.047).
dNGS, digital next-generation sequencing; PDAC, pancreatic ductal adenocarcinoma; UNG, uracil N-glycosylase.