The influence of cancer on a forensic age estimation tool.

The use of epigenetic clocks for measuring age acceleration in the field of cancer research has been a common practice for many years. In forensic genetics, DNA methylation can be used to estimate the age of a stain donor. As lifestyle and disease can alter a person's methylation profile, the accuracy of forensic age estimation tools might decrease compared to the chronological age when estimating a person affected by cancer. In our study, we applied the VISAGE enhanced age estimation tool on blood samples from cancer patients suffering from a variety of cancer entities, including solid and hematologic tumours. A comparison of the age estimation errors between the cancer patients (n = 100) and a healthy control cohort (n = 102) revealed small statistically significant differences and a tendency towards age acceleration in the blood of these patients. Although this study showed that in patients with aggressive cancers (like CLL or AML) estimation accuracy is clearly decreased, for most entities the observed differences were subtle and an analysis of individual CpG sites did not reveal strikingly different methylation patterns. Conclusively, age estimation on blood stains from cancer patients might not result in significantly higher estimation errors, except for very aggressive forms of cancer.