The Effects of Poverty on Human Genes

April 5, 2019

A new Northwestern University study challenges prevailing understandings of genes that long-term poverty can be “embedded” across the genome.

Previous research has shown that socioeconomic status (SES) is a powerful determinant of human health and disease, and social inequality is a ubiquitous stressor for human populations globally. Furthermore, lower SES is associated with physiological processes that contribute to the development of disease, including chronic inflammation, insulin resistance and cortisol dysregulation, but the underlying mechanisms through which our bodies ‘remember’ the experiences of poverty are not known.

In this study, researchers discovered that lower socioeconomic status is associated with levels of DNA methylation (DNAm) — a key epigenetic mark that has the potential to shape gene expression — at more than 2,500 sites, across more than 1,500 genes.

Lead author Thomas McDade said the findings were significant. "Our findings suggest that DNA methylation may play an important role, and the wide scope of the associations between SES and DNAm is consistent with the wide range of biological systems and health outcomes we know to be shaped by SES." said McDade, professor of anthropology in the Weinberg College of Arts and Sciences at Northwestern and director of the Laboratory for Human Biology Research.

"There is no nature versus nurture," he added.

"This pattern highlights a potential mechanism through which poverty can have a lasting impact on a wide range of physiological systems and processes," he said.

Follow-up studies will be needed to determine the health consequences of differential methylation at the sites the researchers identified.

The study has been published in the American Journal of Physical Anthropology.