Use of Methylation Markers for Age Estimation of an Unknown Individual Based on Biological Traces

Biological samples and traces collected at crime scenes have potential to be used for predicting the age of the individuals from whom the samples originated. In no-suspect cases and cases with no DNA profile match against a database, such information could be critical for providing additional intelligence for criminal investigations. 41 CpG sites from the human genome were selected and over 420 samples from men and women between the ages of 2–75 years were investigated to determine the degree of methylation at those potential markers using bisulfite conversion and Pyrosequencing^® methodology. Based on these results, the most significantly correlated CpG sites were used to build an age prediction model. To facilitate the technical analysis, the lowest possible number of markers were selected without lowering the prediction accuracy significantly. The standard error of age estimation using this set of markers was 4.5 years.