Diseases
Researchers link genetic errors to schizophrenia
By Ben Wasserman
Mar 29, 2008 - 4:03:28 PM

SATURDAY March 29, 2008 (foodconsumer.org) -- Certain rare genetic deletions and duplications are more commonly present in people with Schizophrenia than healthy individuals and the mutations disrupt gene normal functions related to brain development and neurological function, two U.S. teams reported on March 27.

The rate of the rare genetic mutations in patients with Schizophrenia was found to be four times higher than those with the disease, according to the researchers.

Researchers at the University of Washington and Cold Spring Harbor Laboratories had uncovered that genetic errors namely mutations due to deletions and duplications are more common in people with the mental disorder, and that many of those errors occur in genes related to brain development and neurological function.

The findings, which were replicated by a team of researchers at the National Institute of Mental Health, were published in the March 27 online edition of the journal Science.

Schizophrenia, a debilitating psychiatric disorder, causes hallucinations, delusions, and disorganized thinking, and people with the disease are at risk for unusual or bizarre behaviors. The condition affects approximately 1 percent of Americans.

For the study, Tom Walsh, Jon McClellan, and Mary-Claire King at the UW, and Shane McCarthy and Jonathan Sebat at Cold Spring Harbor analyzed DNA from 150 people with schizophrenia and 268 health individuals for genetic errors -- rare DNA deletions and duplications contributing to the development of the disease.

The researchers found rare deletions and duplications of genes in 15 percent of those with schizophrenia and only 5 percent in the healthy individuals.  Of those who were stricken by the disease at a younger age, 20 percent had a rare mutation.

Anjene Addington and Judith Rapoport at the National Institutes of Mental Health replicated the same results. They found a higher rate of rare duplications or deletions in patients whose schizophrenia started before age 12 years, which is a very rare and severe form of the disorder.

Early research was focused on mutations that are shared by all the patients with schizophrenia and researchers assumed that the same mutations lead to the same disorder.  The current research demonstrated that schizophrenia may be attributed to different genetic errors although the same genes may be involved.