Table II.
Nature of the Base Substitutions in the Ig VHDJH Gene Segment of CLL B Cells In Vivo and In Vitro
| In vivo shared point-mutations | In vivo partially shared and unique point-mutations | In vivo induced point-mutations | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Transitions | G > A | A > G | C > T | T > C | Transitions | G > A | A > G | C > T | T > C | Transitions | G > A | A > G | C > T | T > C |
| 72 | 24 | 27 | 17 | 4 | 39 | 9 | 8 | 12 | 10 | 9 | ||||
| [12.8] | [10.6] | [9.8] | [10.2] | [7.4] | [5.9] | [5.4] | [5.6] | |||||||
| Transversions | G > C | A > C | C > A | T > A | Transversions | G > C | A > C | C >A | T > A | Transversions | G > C | A > C | C >A | T > A |
| 27 | 11 | 9 | 4 | 3 | 12 | 4 | 2 | 3 | 3 | 1 | 1 | 0 | 0 | 0 |
| [12.8] | [10.6] | [9.8] | [10.2] | [7.4] | [5.9] | [5.4] | [5.6] | [1.2] | [0.92] | [0.92] | [0.92] | |||
| G > T | A > T | C > G | T > G | G > T | A > T | C > G | T > G | G > T | A > T | C > G | T > G | |||
| 29 | 5 | 10 | 5 | 9 | 23 | 7 | 5 | 7 | 4 | 2 | 1 | 0 | 01 | |
| [1.2] | [0.92] | [0.92] | [0.92] | |||||||||||
| Total | G > N | A > N | C > N | T > N | Total | G > N | A > N | C > N | T > N | Total | G > N | A > N | C > N | T > N |
| 128 | 40 | 46 | 26 | 16 | 74 | 20 | 15 | 22 | 17 | 12 | 6 | 1 | 0 | 5 |
| [38.4] | [31.8] | [29.4] | [30.7] | [22.2] | [17.7] | [16.2] | [17] | [3.6] | [2.76] | [2.76] | [2.76] | |||
Shared, partially shared, and unique point-mutations in the Ig VHDJH gene segment of CLL B cells were analyzed in vivo and after in vitro induction.
Identical mutations in different transcripts of the same and different isotypes were assumed not to be independent and were counted only once.
The [expected] number of mutations (from a given nucleotide residue to another given nucleotide residue) was normalized for the base composition of the unmutated VHDJH sequence. It was calculated by multiplying the frequency of occurrence of the nucleotide target of mutation in the unmutated sequence by the total number of observed mutations, and dividing this product by three. For instance, the expected number of G > A mutations was calculated by multiplying 0.30 (G frequency of occurrences the unmutated VHDJH sequence) by 128 = 38.4, divided by 3 (as G > A, G > C, and G > T mutations have all the same theoretical probability to occur) = 12.8.
Shared point-mutations in the Ig VHDJH gene segment of CLL 7, 216, 48, 175, 249, 165, 178, 136, 113, 169, and 105.
Partially shared and unique point-mutations in the Ig VHDJH gene segment of CLL 270, 141, 156, 175, 113, 169, 261, and 105.