Dr. Jana Naue

Over the last few years it became clear that additional information is hidden wi-
thin epigenetic modifications of the DNA, and that especially DNA methylation
(DNAm) could provide useful evidence to the criminal justice system. Within this
project, specific changes in DNAm levels upon age progression at selected loci were
used to develop an objective scientific tool to determine the chronological age of
an (unknown) individual. This information can be used to narrow down the list
of suspects during criminal investigations or to determine the age of a person in
other legal contexts such as human trafficking. A model for age prediction based
on whole blood samples, 13 selected age-dependent DNAm markers, and a ran-
dom forest regression (RFR) approach was developed. The analysis of the DNAm
was performed using amplicon based massive parallel sequencing (MPS) and the
RFR model created with the R package RandomForest. The performance of the
model was evaluated using cross-validation for the training set and by indepen-
dent analysis of an additional test set. Within the seminar, a short introduction
into the field of forensic (epi-)genetics, the marker selection and development of
the DNA methylation tool based on RFR and MPS as well as the results of the
age-determination tool will be presented. Furthermore, the potential and (current)
limitations of the experimental and machine learning approach in respect to the
implementation into forensic investigations will be discussed. The here presented
project of the University of Amsterdam in cooperation with the Netherlands Fo-
rensic Institute was funded by the NCTV grant of the Dutch Ministry of Security
and Justice.