Versions of a gene linked to schizophrenia may trigger runaway pruning of the teenage brain’s still-maturing communications infrastructure, NIH-funded researchers have discovered. People with the illness show fewer such connections between neurons, or synapses. The gene switched on more in people with the suspect versions, who faced a higher risk of developing the disorder, characterized by hallucinations, delusions and impaired thinking and emotions.
“Normally, pruning gets rid of excess connections we no longer need, streamlining our brain for optimal performance, but too much pruning can impair mental function,” explained Thomas Lehner, Ph.D., director of the Office of Genomics Research Coordination of the NIH’s National Institute of Mental Health (NIMH), which co-funded the study along with the Stanley Center for Psychiatric Research at the Broad Institute and other NIH components. “It could help explain schizophrenia’s delayed age-of-onset of symptoms in late adolescence/early adulthood and shrinkage of the brain’s working tissue. Interventions that put the brakes on this pruning process-gone-awry could prove transformative.”