Methylation-based forensic age estimation on different biogeographic backgrounds: A study on Central Europeans, East Asians and West Africans

In recent years, the estimation of the age of a stain donor through DNA methylation has received much attention in the forensic genetics community. It can provide investigative leads for law enforcement when no DNA profile match could be obtained from a crime scene stain. It has been shown that different human populations can have systematically different methylation profiles. This raises the question whether the age of individuals from different biogeographic backgrounds is estimated with different accuracies using forensic age estimation tools. In our study, we investigated 30 individuals each from Central Europe, East Asia and West Africa. All individuals donated blood, saliva and buccal cell samples and each sample was analyzed with two forensic age estimation tools (VISAGE enhanced tool and Jung et al. SNaPshot tool). Our study showed that there were no statistically significant differences in age estimation accuracy between the three investigated populations regardless of the body fluid or age estimation tool used. The only exception was in the saliva samples, which showed statistically significant differences in age estimation errors with the VISAGE enhanced tool when comparing the East Asian and West African groups. Including knowledge about the biogeographic origin of a stain donor might therefore not be as important as previously assumed.