Figure 1From: Sequence artefacts in a prospective series of formalin-fixed tumours tested for mutations in hotspot regions by massively parallel sequencing Association of fragmentation of DNA in FFPE samples with low sequencing coverage. Coverage of each sample (number of reads) versus the copies of the FTH1 gene as assessed by a Taqman PCR assay (copies per microlitre). n = 253. There was a positive correlation between the FTH1 result and coverage (Spearman correlation, r = −0.29, p < 0.0001). The 50 samples with the highest C>T/G>A levels in the 1-10% allele frequency range are shown in red.Back to article page