DNA methylation age is elevated in breast tissue of healthy women

Mary E. Sehl, Jill E. Henry, Anna Maria Storniolo, Patricia A. Ganz, Steve Horvath

Research output: Contribution to journalArticle

23 Scopus citations


Background: Limited evidence suggests that female breast tissue ages faster than other parts of the body according to an epigenetic biomarker of aging known as the “epigenetic clock.” However, it is unknown whether breast tissue samples from healthy women show a similar accelerated aging effect relative to other tissues, and what could drive this acceleration. The goal of this study is to validate our initial finding of advanced DNA methylation (DNAm) age in breast tissue, by directly comparing it to that of peripheral blood tissue from the same individuals, and to do a preliminary assessment of hormonal factors that could explain the difference. Methods: We utilized n = 80 breast and 80 matching blood tissue samples collected from 40 healthy female participants of the Susan G. Komen Tissue Bank at the Indiana University Simon Cancer Center who donated these samples at two time points spaced at least a year apart. DNA methylation levels (Illumina 450K platform) were used to estimate the DNAm age. Results: DNAm age was highly correlated with chronological age in both peripheral blood (r = 0.94, p < 0.0001) and breast tissues (r = 0.86, p < 0.0001). A measure of epigenetic age acceleration (age-adjusted DNAm Age) was substantially increased in breast relative to peripheral blood tissue (p = 1.6 × 10−11). The difference between DNAm age of breast and blood decreased with advancing chronologic age (r = −0.53, p = 4.4 × 10−4). Conclusions: Our data clearly demonstrate that female breast tissue has a higher epigenetic age than blood collected from the same subject. We also observe that the degree of elevation in breast diminishes with advancing age. Future larger studies will be needed to examine associations between epigenetic age acceleration and cumulative hormone exposure.

Original languageEnglish (US)
Pages (from-to)209-219
Number of pages11
JournalBreast Cancer Research and Treatment
Issue number1
StatePublished - Jul 1 2017


  • Biomarker of aging
  • Breast cancer
  • Cell cycling
  • DNA methylation
  • Epigenetics
  • Estrogen
  • Tissue aging

ASJC Scopus subject areas

  • Oncology
  • Cancer Research

Fingerprint Dive into the research topics of 'DNA methylation age is elevated in breast tissue of healthy women'. Together they form a unique fingerprint.

Cite this