Early life stress, such as an extreme lack of parental affection, has lasting effects on a gene important to normal brain processes and also tied to mental disorders, according to a new animal study in the Sept. 29 issue of The Journal of Neuroscience.
In the last decade, researchers have found evidence that experiences can alter the form and structure of DNA, an effect known as epigenetics. In the last decade, researchers have found evidence that experiences can alter the form and structure of DNA, an effect known as epigenetics.
The authors explored how differences in a mother’s attention affect the GAD1 gene, which controls the production of a chemical vital to brain cell communication called GABA. Research indicates that GABA helps to regulate emotion, and that people with schizophrenia may have GABA deficits
They found when the baby rats that were seldom touched grew up, specific regions of the DNA that controls the GAD1 gene were obstructed, likely leading to smaller amounts of GABA. On the other hand, adult rats coddled in the extreme as pups showed increased GAD1 gene production.
Just as in complex systems small perturbations at the beginning have huge impact on the outcome later, scientists in these researchers found that small changes in maternal care had long lasting changes even into adulthood.
"We already knew that maternal care determined the stress responses of an offspring through a similar process, but this is the first time maternal care has been shown to link, via epigenetics, with a key enzyme that causes a major human disorder," said Jonathan Seckl, MD, PhD, of The University of Edinburgh, and an expert on the molecular process of hormones.