Extended Data Fig. 14: Distribution of the new T>A signature across three samples.

a, Signatures for a sample with high rates of the novel signature (PD37240). The left panel shows phylogenetic trees with each branch coloured by the proportion of mutations in that branch assigned to the different mutational signatures. The contribution from the new signature is coloured purple. The middle panel shows the overlay of clones onto an H&E-stained liver section. Clones are coloured on a grey-to-purple scale according to the proportion of mutations attributed to the novel signature. The right panel shows observed mutation spectra for representative clones with low (top) or high (bottom) burden of the novel signature, laid out as for Fig. 4b. Purple arrows indicate parts of the mutation spectrum that are characteristic of the new mutational signature. b, c, In one patient with NAFLD, we had three samples from 2008 (not shown as the signature was absent), 2011 (b) and 2013 (c), with the relative contribution of the signature increasing over time. The photomicrograph of the H&E section in c was captured after the microdissections were excised, hence the white gaps in the tissue.