Risk genes show up in newborns’ brain scans

UNC-CHAPEL HILL (US) — Brain scans of newborns show the same brain changes that appear in adults with gene variants linked to Alzheimer’s, schizophrenia, autism, and other disorders.

“These results suggest that prenatal brain development may be a very important influence on psychiatric risk later in life,” says Rebecca C. Knickmeyer, lead author of a study published online by the journal Cerebral Cortex, and assistant professor of psychiatry in the University of North Carolina School of Medicine.

The study included 272 infants who received MRI scans shortly after birth. The DNA of each was tested for 10 common variations in 7 genes that have been linked to brain structure in adults. These genes have also been implicated in conditions such as schizophrenia, bipolar disorder, autism, Alzheimer’s disease, anxiety disorders, and depression.

For some polymorphisms—such as a variation in the APOE gene which is associated with Alzheimer’s disease—the brain changes in infants looked very similar to brain changes found in adults with the same variants, Knickmeyer says. “This could stimulate an exciting new line of research focused on preventing onset of illness through very early intervention in at-risk individuals.”

But this was not true for every polymorphism included in the study, says John H. Gilmore, senior author of the study and Professor and Vice Chair for Research and Scientific Affairs in the department of psychiatry.

For example, the study included two variants in the DISC1 gene. For one of these variants, known as rs821616, the infant brains looked very similar to the brains of adults with this variant. But there was no such similarity between infant brains and adult brains for the other variant, rs6675281.

“This suggests that the brain changes associated with this gene variant aren’t present at birth but develop later in life, perhaps during puberty,” Gilmore says.

“It’s fascinating that different variants in the same gene have such unique effects in terms of when they affect brain development,” says Knickmeyer.

The National Institutes of Health funded the study.

Source: UNC-Chapel Hill