APOBEC3 hypermutated CTNNB1 sequences from purified human CD4+ T cells. (A) A collection of sequences bearing all the hallmarks of APOBEC3 editing from interferon α treated purified human CD4+ T cells – monotonously substituted with a penchant for GpA. (B) A collection of sequences, this time C->T hypermutants from activated human CD4+ T cells. (C) A collection of sequences recovered from unstimulated CD4+ T cells as control for the above. The first group of 10 shows mixed sequences with both C->T and G->A substitutions, the annotation is as for Figure 1D. The second group of two sequences is monotonously G->A substituted with a penchant for GpA. (D) Three different mutated CTNNB1 molecular clones A, B and C were mixed and amplified by 3DPCR. The lower three sequences are recombinants of the input sequences and denoted as B and C and A and B, the regions of recombination being highlighted in grey. (E and F) 5′ Dinucleotide context for the G->A and C->T transitions, with the expected values shown as horizontal bars, NS, unstimulated.