White Matter Defects May Lead to Schizophrenia

TUESDAY, April 24 (HealthDay News) -- Defects in the brain's white matter, which is responsible for communication between parts of the brain, may be a key genetic factor contributing to schizophrenia, a new study suggests.

"This is the first clear demonstration of a new mechanism by which aspects of schizophrenia and other disorders could be produced," said study senior author Gabriel Corfas, an associate professor of neurology and otolaryngology at Harvard Medical School.

"On the one hand, this may help us to understand and start thinking about novel treatment strategies," added Corfas, a member of the neurobiology program at Children's Hospital Boston. "Secondly, this may help in early detection and, nowadays, we know that this is critical."

---

---

The study also illuminates how two genes previously linked to schizophrenia actually contribute to the disease, the researchers said.

Schizophrenia is a devastating disease that affects some 1 percent of the world's population. According to the U.S. National Institute of Mental Health, people with the disease sometimes hear voices that aren't there, believe that others are broadcasting their thoughts to the world, or become convinced that others are trying to harm them. These fears can make patients withdrawn and cause difficulties when they try to have relationships with others.

The causes of schizophrenia aren't clear but, in the last decade, there's been a growing awareness that patients with this and other neuropsychiatric disorders may have defects in the white matter of the brain.

"Until now, it was not clear whether the white matter defects are a cause of the disease or a result of being treated with drugs and being sick," Corfas explained.

Also, prior studies had linked schizophrenia to the genes for neuregulin 1 (NRG1), a growth factor involved in brain development, along with erbB4, a receptor on brain cells through which NRG1 works.

"It was found that if people have particular variants, the likelihood that they will have neuropsychiatric disease is enhanced," Corfas said. "We had hypothesized for many years that these genes were important for formation of white matter, so that brought together the possibility that maybe these genes, when they are defective, generate white matter that is defective and that causes aspects of neuropsychiatric disorder."