Table 1.
Mutation characteristics in STAT6 exons 12–14.
| Number of mutations observed | Number of motifs in sequence | Number of expected mutation * | Ratio observed/expected | P value ° | |
|---|---|---|---|---|---|
| Transversions/Transitions | 22/6 | - | 18,7/9,3 | 1,83 | 0,2301 |
| A:T base pairs | 20 | 158 | 12,1 | 1,65 | 0,003542 |
| G:C base pairs | 8 | 207 | 15,9 | 0,5 | |
| Dinucleotides | Number of mutations observed | Number of dinucleotide in sequence | Number of expected mutation | Ratio observed/expected | P value |
| AA | 13 | 20 | 3,077 | 4,225 | 0,0000007 |
| AC | 4 | 19 | 2,923 | 1,368 | 0,5198589 |
| AG | 7 | 20 | 3,077 | 2,275 | 0,0249483 |
| AT | 7 | 13 | 2,000 | 3,500 | 0,0014790 |
| CA | 8 | 27 | 4,154 | 1,926 | 0,0563318 |
| CC | 0 | 34 | 5,231 | 0,000 | 0,0068772 |
| CG | 0 | 9 | 1,385 | 0,000 | 0,3715297 |
| CT | 1 | 32 | 4,923 | 0,203 | 0,0509948 |
| GA | 10 | 23 | 3,538 | 2,826 | 0,0012213 |
| GC | 1 | 24 | 3,692 | 0,271 | 0,1614790 |
| GG | 0 | 33 | 5,077 | 0,000 | 0,0066356 |
| GT | 0 | 24 | 3,692 | 0,000 | 0,0410432 |
| TA | 0 | 2 | 0,308 | 0,000 | 1,0000000 |
| TC | 0 | 26 | 4,000 | 0,000 | 0,0254541 |
| TG | 5 | 42 | 6,462 | 0,774 | 0,6709954 |
| TT | 0 | 16 | 2,462 | 0,000 | 0,1554094 |
*
Expected mutation frequencies were calculated according to the sequence composition, assuming random targeting of the mutations at a 28/365 rate for single nucleotide changes and 56/364 rate for dinucleotide mutations.
°
Statistical comparisons were done with the exact binomial test, which compares the observed frequency to the expected one under null hypothesis. The dinucleotides which were significantly targeted by mutations are highlighted in bold.