(A) Nucleotides opposite to the AP sites. TLS reaction was carried out on the templates containing 28AP or 43AP by Polη, Polζ, or a mixture of Polη and Polζ (η+ζ). The fully extended TLS products were analyzed by NGS, and the nucleotides inserted opposite to the AP sites (colored bars), single nucleotide and multi-nucleotide deletions to skip the lesion (open and grey bars, respectively), more than one nucleotide insertions over the lesion (striped bar) and others (black bar) were quantified. (B) Analysis of the multi-nucleotide deletions at AP sites. Shaded sequences indicate the sites of deletion at indicated percentages in the TLS products. The red “X” is the position opposite to the AP site. All the deletions produced at the frequencies above 0.1% in each TLS product were shown. (C) Effects of AP sites on base substitutions in the flanking regions. Base substitutions that were changed by the presence of AP sites were calculated by subtracting the substitution frequencies on the undamaged template from the frequencies on the AP-containing templates.