| spontaneously | 9 | manner |
| from exposure to environmental toxicants | 7 | cause |
| during life | 7 | temporal |
| mutation → can → occur | 70 |
| mutation → can → arise | 13 |
| mutation → can → happen | 10 |
| mutation → could → occur | 7 |
| mutation → could → arise | 4 |
| negative | neutral | positive |
| 0.327 | 0.635 | 0.038 |
| Raw frequency | 104 |
| Normalized frequency | 0.718 |
| Modifier score | 0.367 |
| Perplexity | 184.442 |