DNA Methylation as a Coming Clue for Age Prediction.

Abstract

Background: DNA methylation (DNAm) is a biochemical modification which occurs over the lifespan of an individual and it is a substantial constituent in the aging process. The degree of methylation was significantly related to age. So far, the ELOVL2 locus has been the most thoroughly studied age marker. This locus has been demonstrated to be reliable in ancient and fresh human bloodstains, which constitute a major source of DNA in forensic laboratories. Aim of work: The current study aimed to assess the use of DNA methylation on the ELOVL2 gene from blood samples as biomarkers for chronological age estimation using pyrosequencing in Egypt. Material and methods: Eighty whole blood samples from individuals aged 18-69 years divided into 4 groups were analysed using a DNA methylation quantification assay based on bisulphite conversion and DNA pyrosequencing of 7 CpG sites in the ELOVL2. Results: Our results display significantly strong correlation between DNAm and chronological age; the model supporting DNAm as a strong age predictor. The age prediction accuracy was most accurate in age group III (>40-50y) and was least accurate in age group IV of the elderly individuals (>50-69 y) on choosing1, 2.5-, and 5-years as difference threshold.