For many years, scientists have known that genetic variants, or differences in DNA code across people, play some role in neurological and psychiatric disorders. But the details were murky. Now, researchers at the UNC School of Medicine are using a combination of cell lines and DNA sequencing approaches to look closely at our genomes and identify which genetic variants and genes play roles in influencing one's risk for neurological and psychiatric disorders.

A research team led by Jason Stein, Ph.D., associate professor of genetics and member of the UNC Neuroscience Center, has used a live-cell model system of the human brain to identify the function of genetic variants important for increasing the risk of developing schizophrenia, autism spectrum disorder , and bipolar disorder.

The results were published in Nature Neuroscience . "There are hundreds of different locations on our genome that are associated with psychiatric disorders ," said Stein, who is also a member of UNC Lineberger Comprehensive Cancer Center. "But these locations are in regions of the genome where the function is not well understood.

We supposed that some genetic variants function only when stimulated by certain neural pathways important for brain development." Out of our entire genome, just 3% is responsible for creating codes that lead to the formation of proteins—the "machines" that perform needed tasks in our bodies. The other 97% of the genome does not code for proteins.

It is in these "non-coding".