A donated brain must be received within 24 hours of death. Scientists divide the brain into its left and right hemispheres. One hemisphere is placed in a preservative for anatomical studies; the other is sliced in sections and frozen, a process that preserves all the chemicals, protein, and DNA for biochemical and genetic analysis.
At the brain bank, Benes and other scientists analyze brains to determine what she calls their "gene expression profiles."
These profiles analyze more than 30,000 genes, revealing which ones are turned on or off in specific regions of the brain, in particular disorders. Erratic gene activity can lead to disease.
In October the bank will launch a national databank for these profiles, with free access for scientists worldwide.
Making A Withdrawal At The Brain Bank
Research progress depends largely on "the availability of quality brains," says Lynn Selemon, an anatomist and research scientist specializing in brain structure in the neurobiology department at Yale University in New Haven.
Selemon, a specialist on schizophrenia and Huntington's disease, credits brains from the Harvard bank for helping her achieve a breakthrough in her research.
Imaging studies, she explains, had shown that the prefrontal cortexthe region of the brain above and behind the eyeswas slightly smaller in individuals who were schizophrenic.
Selemon examined tissue samples from schizophrenics, and discovered that their prefrontal cortex was smaller because the cells were packed more densely. She also deduced that much of the machinery that connects nerve cells was missing, thus hampering the cells' ability to communicate.
John Trojanowski also uses the brain bank. He directs both the Institute on Aging and the Alzheimer's Disease Center at the University of Pennsylvania School of Medicine in Philadelphia. By examining glial cells from brains from the bank, he and his colleagues identified the molecular defect in patients with Multiple System Atrophy, whose symptoms resemble Parkinson's disease. He found that the glial cellswhich produce the fatty insulation on nerve cellsin MSA patients were filled with cellular garbage that prevented them from working.
"The brain bank, and any bank that contains biological samples, is a driver for research," Trojanowski says.
A mind is a terrible thing to waste. For information on donating a brain to the Harvard Brain Tissue Resource Center, call (800) 272-4622.
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