Researchers have identified genes associated with people’s general cognitive function – how we process information.
An international team including researchers from the Centre for Healthy Brain Ageing (CHeBA) at UNSW Australia found significant small signals from four genetic regions that were associated with having stronger thinking skills. These regions contained genes that have previously been associated with neurological and psychiatric states.
The study, published in Molecular Psychiatry, was conducted under the auspices of the CHARGE (Cohorts for Heart and Aging Research in Genetic Epidemiology) Consortium. It analysed data from 54,000 people aged more than 45 years old who had taken part in 31 cohort studies including CHeBA’s Sydney Memory & Ageing Study and the Older Australian Twins Study.
Using DNA data, the scientists found general cognitive function was 28 percent heritable in people aged more than 45 years old.
Co-Director of the Centre for Healthy Brain Ageing, Professor Perminder Sachdev said “This study sets the parameters within which gene discovery should be pursued. The discovery of specific genes that influence cognitive function in later life may be related to brain development, maintenance or degeneration, and knowledge of their specific roles can help understand the mechanisms of disease, and ultimately find strategies to alter these mechanisms.”
The participants had all taken a variety of memory and thinking tests which were summarised as a general cognitive ability score. All had genetic testing that examined their DNA in hundreds of thousands of locations. None had dementia or stroke.
Professor Ian Deary, Director of the Centre for Cognitive Ageing and Cognitive Epidemiology (CCACE), The University of Edinburgh, who led the research said, “Before this study we knew that general thinking skills in older age were heritable to some extent, but we did not know which genes were involved. These small genetic signals are like the first lights on a distant shore. We find that, with these types of genetic studies, the larger the number of people tested, the more genetic signals emerge. These findings are exciting in themselves, but they herald more such discoveries as the studies grow in size.”
Professor Sachdev said that CHeBA contributes a number of international collaborations to accelerate positive outcomes in ageing research, particularly in relation to Alzheimer’s disease and other dementias.
“These international collaborations not only provide large sample sizes necessary to address some of the questions, they also provide the ability to replicate the findings of one study in another in a different geographical and ethnic group, and also determine which risk and protective factors are truly universal,” Professor Sachdev said.
The study involved researchers in Australia, Austria, Croatia, Finland, France, Germany, Holland, Iceland, Ireland, Norway, Sweden, the UK and the US.
For more information about CHeBA, visit www.cheba.unsw.edu.au