British study: Schizophrenia doesn't just affect brain; blood test for diagnosis to be developed

From io9.com:

Researchers at the University of Cambridge have discovered that the effects of schizophrenia appear to extend beyond the brain. And now there's talk of a blood test to diagnose schizophrenia being rolled out within a year.

Because schizophrenia is a psychiatric disorder, it was previously believed that the signs of the illness would be contained only within the brain. However, the team at the Cambridge Institute for Psychiatric Research, led by Sabine Bahn, has identified genetic markers of the disorder in cell division, the immune system, and glucose metabolism. They have found that one of the best peripheral indicators of schizophrenia is a systemic problem in protein expression in the skin cells of the patient's arms.

According to Bahn: "It's clear that schizophrenia has a very strong genetic component. Most genes are not used only in the brain. If there is an underlying abnormality at the genetic level that leads to pathology in the brain, the assumption can be made that there should also be dysregulation in the peripheral system. It may not lead to pathology, but it may reflect the pathology in the brain."

The researchers estimate that about 40% of the changes seen in the brains of schizophrenics can be observed elsewhere in their bodies. Although Bahn originally focused on skin cells, she has now shifted to immune cells, which are closer in function to the neurons of the brain. She hopes this will better clarify just how the genetic and psychiatric components of schizophrenia interact.

The main caveat with this study that independent researchers have raised is that these peripheral indicators might not do much to improve our understanding of the root causes of the disorder. However, even if the theoretical implications of this work proves somewhat limited, Bahn hopes the practical implications will be enormous:

Bahn nevertheless believes peripheral-cell-based diagnostics will be useful. She and her coworkers have identified schizophrenia biomarkers in serum, and working with the company Rules-Based Medicine, located in Austin, Texas, and Lake Placid, N.Y., she expects that a serum-based test to aid in the diagnosis of schizophrenia will be launched sometime this year.

"We've identified a signature of numerous protein biomarkers, which give a very high sensitivity and specificity," Bahn says. "We've looked at hundreds of samples from patients and controls and other disorders that are related to schizophrenia."

Currently, it can take several years to definitively diagnose a patient as schizophrenic. These new tests could reduce that figure dramatically. A schizophrenic's long-term well-being can be substantially improved with early detection of the condition.