A Dana Foundation-sponsored lecture by Maria Karayiorgou, M.D., a professor of psychiatry at Columbia University’s Mind Brain Behavior Institute, was a mind boggling, roller coaster ride on the track where neuroscience is pinning much of its hopes: genetics.
Karayiorgou’s lecture was a bit like a trip down Alice in Wonderland’s rabbit hole: the more she and her colleagues uncover, it seems, the further away they are from definitive answers. One reason: The average adult human brain has 80 billion neurons; each neuron has multiple connections. Those connections may number in the trillions, or even quadrillions. Meanwhile, of the 20,000 genes recently discovered in the Human Genome Project, 80 percent relate to the brain.
First trained as a medic and psychiatrist in Athens, Karayiorgou realized that the genome was the key to unraveling the behavioral expressions that accompany so many mental disorders. She studied genetics at M.I.T. and Rockefeller University before landing at Columbia in 2006.
Last night, she announced that her lab recently made an important discovery: a chromosome (22-Q11) that potentially leads to schizophrenia in 30 percent of all individuals. “This is a powerful discovery because it’s the first time we have uncovered a genetic factor with such strong, predictive value,” she said, adding that “it will inspire research programs around the world to try to focus on predictive factors.”
Karayiorgou said it was “a dream come true” to be the first lab to sequence the genes of 300 families. She looked at genes for schizophrenia and autism across all 20,000 genes and found that new mutations were not inherited, but generated anew. But the biggest surprise was that the mutations occurred in many more genes than expected. While they had given up on the idea of a single gene disorder, the thinking was that maybe a dozen or two genes were involved in a disorder such as schizophrenia. The new research put the number between 500 and 1,000.
She compared the reaction to the findings as “hitting rock bottom,” followed by denial, anger, and acceptance. But then came the positive spin: “It’s really not so bad; maybe even empowering.”
On the screen appeared the opening sentence of Anna Karana, published in 1877: “Funny enough, Tolstoy may have predicted it first when he wrote that ‘happy families are all alike; every unhappy family is unhappy in its own way,’” she said. “Extrapolate that to mean that every patient has their own disease-causing mutation.”