Summary: A new study, that utilized machine learning tools, provides a new map that links genetic signatures to functions across the human brain.
Source: McGill University
Many psychiatric disorders have genetic causes, but the exact mechanism of how genes influence higher brain function remains a mystery. A new study provides a map linking the genetic signature of functions across the human brain, a tool that may provide new targets for future treatments.
Led by Bratislav Misic, a researcher at The Neuro (Montreal Neurological Institute-Hospital) of McGill University, a group of scientists performed machine learning analysis of two Open Science datasets: the gene expression atlas from the Allen Human Brain Atlas and the functional association map from Neurosynth. This allowed them to find associations between gene expression patterns and functional brain tasks such as memory, attention, and mood.
Interestingly, the team found a clear genetic signal that separated cognitive processes, like attention, from more affective processes, like fear. This separation can be traced to gene expression in specific cell types and molecular pathways, offering key insights for future research into psychiatric disorders.
Cognition, for example, was linked more to the gene signatures of inhibitory or excitatory neurons. Affective processes, however, were linked to support cells such as microglia and astrocytes, supporting a theory that inflammation of these cells is a risk factor in mental illness. The genetic signature related to affect was centred on a brain region called the anterior cingulate cortex, which has been shown to be vulnerable in mental illness.
Published in the journal Nature Human Behaviour on March 25, 2021, this study draws a direct link between gene expression and higher brain function, by mapping gene signatures to functional processes across the human brain.
“In this work we found molecular signatures of different psychological processes,” says Misic. “This is exciting because it provides a first step to understand how human thoughts and emotions arise from specific genes, biological pathways and cell types.”
Funding: This research was funded by the Canada First Research Excellence Fund, awarded to McGill University for the Healthy Brains, Healthy Lives initiative, the Natural Sciences and Engineering Research Council of Canada, the Canada Research Chairs Program, the National Institutes of Health, the Canadian Institute for Advanced Research, and Google.
About this genetics research news
Source: McGill University Contact: Shawn Hayward – McGill University Image: The image is credited to The Neuro
Mapping gene transcription and neurocognition across human neocortex
Regulation of gene expression drives protein interactions that govern synaptic wiring and neuronal activity. The resulting coordinated activity among neuronal populations supports complex psychological processes, yet how gene expression shapes cognition and emotion remains unknown.
Here, we directly bridge the microscale and macroscale by mapping gene expression patterns to functional activation patterns across the cortical sheet.
Applying unsupervised learning to the Allen Human Brain Atlas and Neurosynth databases, we identify a ventromedial–dorsolateral gradient of gene assemblies that separate affective and perceptual domains. This topographic molecular-psychological signature reflects the hierarchical organization of the neocortex, including systematic variations in cell type, myeloarchitecture, laminar differentiation and intrinsic network affiliation. In addition, this molecular-psychological signature strengthens over neurodevelopment and can be replicated in two independent repositories.
Collectively, our results reveal spatially covarying transcriptomic and cognitive architectures, highlighting the influence that molecular mechanisms exert on psychological processes.