Bram Bekaert

The blood test, for example, has an accuracy of about 3.75 years over a whole age population, meaning that from newborns up to about 91 years of age our accuracy was about 3.75, the younger the individual is the higher the accuracy is because it has had less influence of the environment. So the more a person has an influence over the environment on his epigenome, as we call it, so the chemical structures on the genome the larger the error rate will become. So the error rate for younger people is about two years of age, while for 91 years of age it will be about five and a half, six, years of age.

The nice thing about this kind of analysis as well is that it can be used in cold cases as well, because the chemical structures on the DNA do not degrade, they're stuck there as long as the DNA is there. So in cases where you have blood stains from 20 years ago, for example, you can actually go back and look at how old that suspect - or that perpetrator - was, for example.