Congratulations Drs.Okun and Vaillancourt on the publication of “Multimodal Neuroimaging and Behavioral Assessment of SNCA Polymorphism rs356219 in Older Adults,” in the February 10th issue of Neurobiology of Aging.
The single nucleotide polymorphism rs356219 in the α-synuclein (SNCA) gene has been shown to significantly contribute to an earlier age at onset of Parkinson’s disease (PD), regulate SNCA expression in PD-brain regions, blood and plasma. Here, we used multimodal MRI to study healthy adults with and without the rs356219 risk genotype. Motor and cognitive tests were administered and all participants underwent functional and structural MRI. Imaging analyses included: 1) task-based functional MRI, 2) task-based functional connectivity, 3) free-water diffusion MRI of the substantia nigra, 4) voxel-based morphometry, 5) surface-based morphometry. There were no differences between the two groups in motor and cognitive performance, or brain structure. However, carrying a PD risk variant was associated with reduced functional activity in the posterior putamen and primary motor cortex. Moreover, the posterior putamen had reduced functional connectivity with the motor cortex during motor control in those with a risk genotype compared to those without. These findings point to functional abnormalities in the striato-cortical circuit of rs356219 risk genotype carriers.