Nowadays, forensic phenotyping, aiming to infer the unknown sample donor’s appearance from DNA, is expected to reduce the number of potential suspects (4, 5). To date, the most well studied externally visible characteristic (EVC) markers are the single nucleotide polymorphism (SNP) markers associated with pigmentation, e. g., the variations in the coloration of the iris, hair, and skin (6–8). However, such pigmentation markers may not be useful in certain populations such as Asians and Africans with little color variation. More recently, age has been suggested as an EVC that can be used regardless of ethnicity to predict an individual’s appearance, thereby providing an investigative lead to track an unknown suspect or identify a missing person. …show more content…
This test has shown relatively high prediction accuracy with an error of 9 years. However, this method cannot be applied to the age prediction of other body fluids that do not include T-cells and needs to be tested using patients’ blood samples because of its immune-dependent characteristics. In the meantime, the advancement of epigenetics led to the identification of a number of CpG markers, exhibiting age-associated DNA methylation changes in various types of tissues and cells. Several studies have reported age-predictive models that could be applied across broad spectrum of tissues as well as those based on the use of blood or saliva with considerable prediction accuracy (<5 years) (10–13). To date, DNA methylation is regarded as the most promising age-predictive