Epigenetic age oscillates during the day (WBC-Neu 52 yr old)

Since their introduction, epigenetic clocks have been extensively used in aging and human disease research. In this study, we reveal an intriguing pattern: epigenetic age predictions display a 24-hour periodicity. These paradoxical age oscillations can be attributed to variations in blood cell type composition and epigenomes, both of which demonstrate circadian rhythmicity. This discovery emphasizes the significance of factoring-in the time of day to obtain accurate estimates of epigenetic age. Peripheral blood samples were collected continuously every 3 hours for 72 hours from a 52 year old caucasian male. Collection started at circadian time 13 (CT13), corresponding to 1PM local time with one missing time point at CT52. Methylation profile obtained using Illumina Infinium 450K Human Methylation Beadchip. The microarray experiment was performed in technical duplicates. Sample WBCminusNeu_ZT82 and it's technical replicate were removed as outliers during the analysis and are not included in the processed data.