Researchers have identified a gene that underlies healthy information processing, a finding that may pave the way for a better understanding of cognitive ageing and age-related diseases, such as Alzheimer’s.
An international team of researchers, including investigators from the University of Mississippi Medical Center (UMMC), conducted one of the largest genetics study to date to link a specific genetic mutation and information processing speed.
“It is well known that genetic variation plays an important role in explaining individual differences in thinking skills such as memory and information processing speed,” said senior scientist Tom Mosley, director of the Memory Impairment and Neurodegenerative Dementia (MIND) Center at UMMC.
“However, the genes that underlie thinking skills remain largely unknown. Our team has identified a genetic mutation that may help unravel this puzzle,” Mosley said.
Researchers analysed data from more than 30,000 people who were 45 or older, bringing together data from participants in several studies in 12 different countries.
They also examined genetic variations across 2.5 million sites along each individual’s DNA, looking for associations between genetic variants and performance on several different tests of cognitive function.
Of the different cognitive skills examined, the strongest genetic association was related to performance on a test of information processing speed. The most associated variants were located in the CADM2 gene, also known as Syncam2.
“It seems like, through this genetic analysis, we have identified a genetic variant which partly explains the differences in information processing speed between people,” said lead author Carla Ibrahim-Verbaas, from Erasmus University Medical Center in Netherlands.
“It confirms the likely role of CADM2 in between-cell communication, and therefore cognitive performance. It is of interest that the gene has also been suggested in other studies to be involved in autism and personality traits,” she said.
Researchers said a protein product from CADM2 is involved in the short-term and long-term chemically mediated communication between brain cells and is abundant in the frontal and cingulate cortex – areas of the brain involved in processing speed as well as in the developing brain.
“We are finding that for complex traits, like cognitive function, not a single gene, but several genes or genetic regions come into play, with each making a relatively small contribution,” Mosley said.
“We now have the technology to measure across the entire genome in a much more fine-grained manner compared to a few years ago, in this case 2.5 million sites, and are able to combine that genetic mapping with large sample sizes,” Mosley said.
The study will be published in the journal Molecular Psychiatry.