Researchers have found that certain types of human genes are responsible for the brain’s resistance to a variety of mental illnesses.
In the world’s largest brain study, more than 200 scientists from 100 institutions identified new genes that they believe can clarify individual differences in brain size and intelligence.
“We hunted for genes that increase the risk for a single disease that the children can inherit,” said senior author Paul Thompson who is a professor of neurology at the David Geffen School of Medicine at UCLA and a member of the UCLA Laboratory of Neuro Imaging.
Researchers 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.
Three years ago, Thompson’s lab collaborated with four investigators who recruited brain-imaging labs around the world to share genomic data and establish the project of ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis).
“By sharing our data with Project ENIGMA, we created a sample large enough to reveal clear patterns in genetic variation and show how these changes physically alter the brain,” explained Thompson.
ENIGMA researchers measured the size of the brain and its memory centers in thousands of MRI images from 21,151 healthy people while screening their DNA.
Results showed that a variant in a gene called HMGA2 affected brain size as well as a person’s intelligence.
“Millions of people carry variations in their DNA that help boost or lower their brains’ susceptibility to a vast range of diseases, therefore, once we identify the gene, we can target it with a drug to reduce the risk of disease,” said Thompson.