Parkinson’s, ADHD Risks Highlighted in Genomic Study of Brain Volume

November 17, 2024Brain volume, and the genetic variants that influence it, is tied to ADHD and Parkinson’s disease risks, suggests one of the most extensive international studies to date on DNA and brain structure.1The new study, published in Nature Genetics, examined how brain size and genetic differences influence key subcortical or ‘deep brain’ regions crucial for memory, emotional regulation, proprioception, sensory processing, and responses to rewards and punishments.A team of 189 researchers from 45 countries analyzed data from genome-wide association studies (GWAS) and magnetic resonance imaging (MRI) brain scans of 74,898 participants across 19 countries.

They identified 254 genetic variants that impact brain volume and the likelihood of developing ADHD and Parkinson’s disease.“Genetic variants associated with larger brain volumes in key brain regions also increase the risk of Parkinson’s disease, while variants linked to smaller brain volumes in key regions are associated with an increased risk of ADHD,” said Miguel Rentería, Ph.D., study principal and associate professor at the Queensland Institute of Medical Research (QIMR Berghofer) in Australia, in a statement. “These findings suggest that genetic influences that underpin individual differences in brain structure may be fundamental to understanding the underlying causes of brain-related disorders.”However, more studies are needed on the causal relationship between genes and brain-based diseases. “It’s worth noting that these are correlations, not causal relationships, and so interpretation must be approached with caution,” Rentería said.“My theory is that the underlying mechanisms involve genes crucial to brain development, growth, and aging processes,”.