Stability of Aging- and Cognition-Related Methylation Profile Scores Across Two Waves in Children and Adolescents

DNA-methylation profile scores (MPSs) index biology relevant for lifelong physical and cognitive health, but information on their longitudinal stability in childhood is lacking. Using two waves of data collected from 2014 to 2022 (Mlag between waves = 2.41 years) from N = 407 participants (Mage = 12.05 years, 51% female, 60% White), test-retest correlations were estimated for four salivary MPSs related to aging (PhenoAgeAccel, GrimAgeAccel, DunedinPACE), and cognitive function (Epigenetic-g). MPSs varied in longitudinal stability (test-retest rs = 0.38 to 0.76). MPSs did not differ in children exposed to the COVID-19 pandemic, but race-ethnic and sex differences were apparent. Further research is necessary to understand which environmental perturbations impact DNA-methylation trajectories and when children are most sensitive to those impacts.