Using a "brain bank" of frozen tissue and the latest techniques in molecular genetics, a consortium of researchers is looking for clues to the causes of depression and schizophrenia. Now the group is partnering with Perlegen Sciences of Mountain View, Calif., to scan thousands of blood samples for genetic variations that might be linked to bipolar disorder.

Since the Pritzker Neuropsychiatric Disorders Research Consortium was established in 2001 with funding from the Pritzker Family Foundation, the group has built up a collection of brains from patients with diagnosed depression or schizophrenia, along with "control" brains matched for age and gender. In the process, they have gained invaluable experience working with and storing the delicate tissues, said Edward Jones, director of the Center for Neuroscience at UC Davis and one of the principal investigators in the consortium.

The researchers dissect small areas of brain tissue and test them with microarray genetic analysis to get a snapshot of which genes are switched on or off. Discovering whether some genes are differently regulated in people with mental illnesses could give clues as to how these diseases are caused and progress.

"We've made some major discoveries in depression," said Jones. In 2004, consortium researchers reported in Proceedings of the National Academy of Sciences that a group of genes related to cell growth was disrupted in patients with major depression. That is in line with the idea that "faulty wiring" -- problems in how different parts of the brain are connected together -- plays a significant role in mental illness.

In the new project, blood samples collected by the National Institute of Mental Health will be tested for genetic variations called single nucleotide polymorphisms, or SNPs, that could be linked to changes seen in the brain studies.

The Pritzker Neuropsychiatric Disorders Research Consortium includes scientists at UC Davis, Stanford University, the University of Michigan, UC Irvine and Cornell University. The consortium was established in 2001 with five years' funding from the Pritzker Family Foundation. Members of the family recently agreed to continue to support the research effort, Jones said.