"GWAS studies lump everybody together but we need to tease out the differences," Leckman said. "I'm not sure the GWAS strategy will get us where we need to go."
Three of every 1,000 children have Tourette syndrome, according to the U.S. Centers for Disease Control and Prevention. The American Psychiatric Association says more than 4 million people have OCD.
"These are chronic conditions; people with OCD and Tourette's deal with it every day. Both, at their worst, are debilitating, and the anxiety is always present," said Alies Muskin, executive director of the Anxiety and Depression Association of America, in Silver Spring, Md.
Tourette syndrome and OCD can be treated with cognitive behavioral and exposure therapy, which train people to deal with their anxiety, Muskin said.
The U.S. National Institute of Mental Health has more about OCD and Tourette syndrome.
SOURCES: Francis J. McMahon, M.D., chief, human genetics branch, intramural research program, U.S. National Institutes of Mental Health, Bethesda, Md.; James Leckman, M.D., Neison Harris Professor of Child and Adolescent Psychiatry, Yale University, New Haven, Conn.; Alies Muskin, executive director, Anxiety and Depression Association of America, Silver Spring, Md.; Aug. 14, 2012, Molecular Psychiatry
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