Table 1.
UV-induced hprt mutation frequencies in mouse primary fibroblasts
|
Polη+/+Polι+/+ frequency (×10−6) |
Polη−/−Polι+/+ frequency (×10−6) |
Polη+/+Polι−/− frequency (×10−6) |
Polη−/−Polι−/− frequency (×10−6) |
|
|---|---|---|---|---|
| Mutation freq.* | 80 [36]† | 550 [48]† | 32 [19]† | 120 [20]† |
| Frameshifts | 4 (2)‡ | 23 (2) | ≤2 (0) | 6 (1) |
| Large deletions§ | 4 (2) | 92 (8) | 2 (1) | 29 (5) |
| Large insertions | 2 (1) | ≤11 (0) | ≤2 (0) | ≤6 (0) |
| Base substitutions at dipyrimidine sites | 60 (27) | 390 (34) | 24 (14) | 87 (15)¶ |
| Tandems | ≤2 (0) | 23 (2) | 5 (3) | 6 (1) |
| Transitions | 31 (14) | 180 (16) | 8 (5) | 41 (7) |
| C·G → T·A | 29 (13) | 100 (9) | 8 (5) | 23 (4)¶ |
| T·A → C·G | 2 (1) | 80 (7) | ≤2 (0) | 17 (3)¶ |
| Transversions | 29 (13) | 180 (16) | 10 (6) | 41 (7) |
| C·G → A·T | 4 (2) | 100 (9) | 2 (1) | 23 (4)¶ |
| C·G → G·C | ≤2 (0) | 11 (1) | ≤2 (0) | ≤6 (0) |
| T·A → A·T | 13 (6) | 57 (5) | 8 (5) | 17 (3)¶ |
| T·A → G·C | 11 (5) | 11 (1) | ≤2 (0) | ≤6 (0) |
Frequency (Freq.) measurements were determined for at least six independent assays and using primary fibroblasts isolated from at least two independent mice.
*Mutation frequencies were determined at UV exposures resulting in 37% cell survival.
†Numbers in brackets are the number of independent mutants sequenced (see Tables 2–5).
‡Numbers in parentheses are the number of independent mutations observed (see Tables 2–5).
§Large deletions are primarily deletions of exons (see Tables 2–5).
¶Three mutants contained multiple mutations separated by >100 nucleotides (see Table 5).