Epigenetic Markers Change Over a Lifetime

M. Daniele Fallin, Ph.D.
Department of Epidemiology
Johns Hopkins Bloomberg School of Public Health
NIEHS Grant R01ES015211

New findings about the epigenetic markers on an individual’s DNA may explain why some people become more susceptible to disease as they age and why individual disease risk is similar within families. NIEHS-funded researchers at the Bloomberg School of Public Health of Johns Hopkins University found that certain DNA methylation patterns or epigenetic markers change during a person’s lifetime and the amount of change is similar among related people.

The research team analyzed DNA methylation in over 200 individuals from two cohorts of subjects; an Icelandic cohort and a group of people from Salt Lake City. Two samples of DNA, taken 11 years apart, were analyzed from the Icelandic population. One third of them had significant changes in their DNA methylation; some higher, some lower. This change over time represents a proof-of-principle than an individual’s epigenetics does change with age.

The Salt Lake City cohort is made up of two and three generation families whose DNA was sampled 16 years apart. The results show that DNA methylation changes tended to be similar among family members—if one member’s level dropped or increased over time, a similar change occurred in other family members.

The study authors conclude that “the implications of these results are potentially profound for population-based studies of human disease.” The epigenetic changes seen over time might directly influence the onset or progression of disease. The epigenetic changes might also reflect age-related or environmental exposures.

Citation: Bjornsson HT, Sigurdsson MI, Fallin MD, Irizarry RA, Aspelund T, Cui H, Yu W, Rongione MA, Ekström TJ, Harris TB, Launer LJ, Eiriksdottir G, Leppert MF, Sapienza C, Gudnason V, Feinberg AP. Intra-individual change over time in DNA methylation with familial clustering. JAMA. 2008 Jun 25;299(24):2877-83.