A batch of new studies published in the last week – including the world’s largest brain study to date – report progress in connecting the dots between genes and mental illness - and may suggest directions for treatment development.
Two hundred scientists from 100 institutions worldwide mapped genetic material or DNA from thousands of people for the studies reported April 15 in Nature Genetics. Their effort identified genetic variations linked to increased risk for a variety of brain functions and conditions, including mental illness and Alzheimer’s disease.
“We searched for two things in this study,” according to senior author Paul Thompson, professor of neurology at the David Geffen School of Medicine at UCLA and a member of the UCLA Laboratory of Neuro Imaging. “We hunted for genes that increase your risk for a single disease that your children can inherit. We also looked for factors that cause tissue atrophy and reduce brain size, which is a biological marker for hereditary disorders like schizophrenia, bipolar disorder, depression, Alzheimer’s disease and dementia” (“New genes linked to brain size, intelligence,” Science Daily).
The multinational study is called Project ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis). Because disorders like Alzheimer’s, autism and schizophrenia disrupt the brain’s circuitry, Project ENIGMA will next search for genes that influence how the brain is wired, Science Daily reported. (Like many academic reports, the original articles are available only to subscribers of Nature Genetics or for a fee.)
Thompson told interviews that the genetic discoveries will eventually lead to treatment advances. "Millions of people carry variations in their DNA that help boost or lower their brains' susceptibility to a vast range of diseases," Thompson said (“Researchers ID genes that may determine mental illness,” US News Health, April 15). "Once we identify the gene, we can target it with a drug to reduce the risk of disease. People also can take preventive steps through exercise, diet and mental stimulation to erase the effects of a bad gene."
In a separate study published in the April 27 print issue of the journal Cell, other scientists reported identifying 33 genes associated with autism and other neurological disorders, including schizophrenia (“Genes associated with autism also related to schizophrenia,” HealthDayNews, April 19).
“The researchers screened the genomes of 38 people with autism or other neurodevelopmental disorders,” according to the HealthDay News summary of the journal article.” A significant number of the genes linked with autism also appear to be associated with schizophrenia and other psychiatric disorders.”