A study from the University of Edinburgh finds how and when brain genes are expressed at different times in a person's life to perform a range of functions. This study recently appeared in eLife.
The scientists measured gene expression in brain tissue samples from across the human lifespan. "Many people believe our brain simply wears out as we age. But our study suggests that brain aging is strictly controlled by our genes," says Nathan Skene, Ph.D., a research scientist at the University of Edinburgh's Centre for Clinical Brain Sciences. However, the researchers found the timing of when different genes are expressed follows a strict pattern across the lifespan and that most changes were completed by middle-age.
The gene program is delayed slightly in women compared with men, suggesting that the female brain ages more slowly than the male. However, according to the researchers, the biggest reorganization of genes occurs during young adulthood, peaking around age 26. These changes affected the same genes that are associated with schizophrenia.
With this finding, it made sense to the team why symptoms of schizophrenia don't show up until young adulthood.
The researchers were able to find that this genetic program was present in mice too, which suggest that it may be present in all mammals.
"The discovery of this genetic program opens up a completely new way to understand behavior and brain diseases throughout life," says Seth Grant, Ph.D., head of the Genes to Cognition laboratory at the University of Edinburgh. Next, the researchers plan to study how the genetic program is controlled, which could lead to therapies that alter the course of brain aging.