Fig. 1

UCSC Browser view of TERT promoter region. The 5’ end of TERT gene is shown in black with arrow indicating the transcription direction. Dark green-colored track shows the CpG Islands track from UCSC browser. Blue-colored track depicts the TERT core promoter and yellow-colored track depicts the THOR region as described in Lee et al. 2019 [27]. Red-colored track shows the TERT promoter region which was screened in the cohort of 87 cell lines for SNVs by Sanger Sequencing. Light purple-colored tracks show the extend of the first TERT BS assay (BS1) used in Hep-G2 and A-549 and the 30 CpG sites included in the assay. Dark purple and dark blue tracks show the TERT sgRNAs [targeting both mutated (C228T-mut) and wildtype (C228T-wt) alleles of the C228T mutation] binding sites. Light blue-colored tracks show the extend of the second TERT BS assay used in A-549 cells (BS2) and the 35 CpG sites included in this assay. Orange track shows the binding site of the sgRNA that targets the alternative G allele of the rs2853669 common SNP (rs2853669-alt). At the lower part of the figure, Hep-G2 and A-549 DNA methylation tracks from the UCSC database are depicted. The DNA Methylation by Reduced Representation Bisulfite Sequencing (RRBS) from ENCODE/HudsonAlpha track is highlighted by a dark gray box on the left (DNA methylation status is represented with an 11-color gradient using the following scales: red = 100%, yellow = 50% and green = 0% of molecules sequenced are methylated). CpG Methylation by Infinium Human Methylation 450 K BeadChip arrays (450 k) from ENCODE/HAIB track is highlighted by a light gray box (orange = methylated [score ≥ 600] and blue = unmethylated [0 < score ≤ 200], where the score has a range of 0–1000)