Imaging genetics and sulcus opening

© NeuroSpin/CEA. Locuszoom display (Pruim et al. 2011) of the phenotype-variants association results for the region upstream of KCNK2 with the left posterior cingulate sulcus opening as a phenotype (see the red sulci in the orange subfigure).

Gray and white matter volumes are known to reduce with age. This cortical shrinkage is visible on magnetic resonance images. Using the UK Biobank dataset, we replicated this finding and studied the genetic influence on these cortical features of aging. We found that the heritability of the sulcal opening ranges from 15 to 45% (SE = 4.8%). We identified 4 new loci that contribute to this opening, including one that also affects the sulci grey matter thickness. We identified the most significant variant (rs864736) on this locus as being an expression quantitative trait locus (eQTL) for the KCNK2 gene. This genetic modulator of cortical shrinking could be a confound in pathological context like Alzheimer’s disease in which brain shrinkage is a key biomarker.

Le Guen, Y., Philippe, C., Riviere, D., Lemaitre, H., Grigis, A., Fischer, C., Dehaene-Lambertz, G., Mangin, J-F., Frouin, V. (2018). eQTL of KCNK2 regionally influences the brain sulcal widening: evidence from 15,597 UK Biobank participants with neuroimaging data. Brain Structure & Function. http://doi.org/10.1007/s00429-018-1808-9