A study conducted by Northwestern University researchers has found that long-term poverty can be “embedded” across the genome. Lower socioeconomic status was found to be associated with levels of DNA methylation, a key epigenetic mark that can influence expression, across more than 1,500 genes in the human body, or around 10% of the genome.

From here, further studies must determine the health consequences of changes in methylation, though the researchers noted that many of the associated genes are related to skeletal development, immune responses to infection and nervous system development.

Lead author Thomas McDade said the findings were significant because: “First, we have known for a long time that SES is a powerful determinant of health, but the underlying mechanisms through which our bodies ‘remember’ the experiences of poverty are not known,” said McDade, professor of anthropology in the Weinberg College of Arts and Sciences at Northwestern and director of the Laboratory for Human Biology Research.

“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.

“There is no nature vs nurture.”