Can Environmental Stress Control Our Genes?

A_coign_of_vantage Environmental stress can destroy protective complexes in human cells and turn on or off selected genes, newly published research shows. External stress agents appear to “instruct” certain enzymes to modify gene behavior, whereby genes that should remain turned off are activated and disturb the development, functioning and growth of human cells. According to Dr. Simmi Gehani, principal researcher at the University of Copenhagen where the study was conducted, this means that external stress factors can control the activity of our genes.

Why is this important? The specific knowledge of how our genes are regulated is important in order to understand how stress can lead to development of disease. The genetic code contained in our DNA is the same as in the over 200 cell types found in our body. Based on the “instructions” contained in our DNA, individual cells develop in different and highly specialized ways. Many genes are only active at specific times during fetal development or in specific cell types in the adult body. The natural deactivation of certain genes at specific time points ensures normal development and maintains proper cellular identity and function.

The new research findings, published in the latest edition of Molecular Cell, show that stress-activating factors can turn on genes that were supposed to remain inactive. These external stress factors are pollution, tobacco smoke, alcohol, drugs, chemical contaminants, or bacterial toxins. They can put a significant stress load on cells, which must react to survive and maintain their normal function. These research findings may help explain the effects that environmental stressors can have on health and functioning.

Additionally, they may also explain the dangers of external stressors to the unborn. During fetal development, exposing human cells to a stress-activating agent can turn on previously inactive genes. This is significant because even small changes in gene activation can have disastrous effects in child development.

There is a widespread belief — often dismissed — that what happens during pregnancy can affect everything that a person becomes in life. This and other research, writes Annie Murphy Paul in her new book Origins: How the Nine Months Before Birth Shape the Rest of Our Lives, may provide evidence to support the claim.