March 28, 2008 -- New research points to what scientists say are genetic clues to very early signs of schizophrenia in children.
Scientists say they've identified a host of genetic mutations that are far more common in people with schizophrenia than in healthy people. While the mutations are rare, they tend to involve genes controlling brain development, a fact researchers say may open windows to intervene early and even prevent the debilitating disease.
Researchers found the mutations, called copy number variants, in 15% of patients with schizophrenia but in only 5% of healthy people. Meanwhile, 20% of young patients with child-onset schizophrenia showed the anomalies.
Copy number variants (CNVs) have also been found to show up more readily in children with autism and mental retardation, says Judith Rapoport, MD, who lead one of two research teams that published the findings. That is leading researchers to suspect that all of the disorders could have common roots in disrupted genes important to brain development.
Looking for Early Signs of Schizophrenia
Schizophrenia affects about one in 100 people. Most are diagnosed in their late teens or early 20s. But for the last several years, researchers have been looking for earlier behavioral signs of impending disease and genetic signs that could serve as a warning for future risk.
"This may be an easier way to hunt for genes or even protective factors," Rapoport says.
But CNVs likely won't be a good predictor of who will get disease and who won't, says Thomas R. Insel, MD, the NIMH director. The mutations show up in both healthy and unhealthy people. Also, CNVs tend to be hereditary but highly specific. That means that a CNV that could help predict a critical genetic mutation in one family but not in another.
"It's not going to provide an easy diagnostic test," Insel says.
What CNVs may provide is a kind of early-alert system, possibly allowing doctors to intervene with targeted drugs before the effects of full-blown-schizophrenia arrive, Rapoport says.
She likened it to HIV infection, which if detected early, can now be headed off with cocktails of antiretroviral drugs. The treatment can slow the progression of disease.
"If I could come up with something like that for schizophrenia, no one here would object, I assure you," Rapoport says.