Table 2.
Incidences of mutations with amino acid substitution and silent mutations of the K‐ras and Egfr genes in animal lung neoplasms
| Treatment | Animal | K‐ras | Egfr | ||||
|---|---|---|---|---|---|---|---|
| Exon 1 | Exon 2 | Exon 18 | Exon 19 | Exon 20 | Exon 21 | ||
| Mutations with amino acid substitution | |||||||
| NNK | Mice | 21/23 (91%) | 0/22 | 0/23 | 0/22 | 0/15 | 0/14 |
| MeIQx | Mice | 4/5 (80%) | 0/5 | 0/5 | 0/4 | 0/4 | 0/5 |
| Urethane | Mice | 0/8 | 1/4 (25%) | 0/4 | 0/4 | 0/5 | 0/3 |
| BHP | Rats | 7/18 (39%) | 0/14 | 0/18 | 0/18 | 0/17 | 0/18 |
| X‐ray | Rats | 0/12 | 0/11 | 3/12 (25%) | 0/11 | 0/12 | 1/11 (9%) |
| Silent mutations | |||||||
| X‐ray | Rats | 1/12 (8%) | 0/11 | 1/12 (8%) | 0/11 | 2/12 (17%) | 1/11 (9%) |
BHP, N‐nitrosobis(2‐hydroxypropyl)amine; Egrf, epidermal growth factor receptor; MeIQx, 2‐amino‐3,8‐dimethylimidazo[4,5‐ƒ]quinoxaline; NNK, 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanone.