Figure 8.

Signature of tumorigenesis and FFPE fixation error through substitution type and context of somatic mutations. (A) Spontaneous deamination of 5-methylcytosine as observed in CRC tumor; (B) signature pattern of tobacco damage as observed in lung tumor; (C) signature pattern of UV damage as observed in melanoma tumor; (D) signature pattern of FFPE sample fixation error; (E) pie charts quantifying the proportion of respective signature. From left to right, pie charts represent elevated rate of (I) spontaneous deamination of 5-methylcytosine footprint (red and blue segments) in CRC tumor, (II) tobacco damage footprint (orange segment) in lung tumor, (III) UV damage footprint (blue, green, and yellow segments) in melanoma tumor, (IV) fixation error footprint (green and purple segments). FFPE, formalin-fixed, paraffin-embedded; CRC, colorectal cancer.