However, a novel aspect is the simultaneous quantification of cortical and white matter tau burden within an individual subject which we show is highly correlated in disease-specific fashion: tau burden in AD samples was largely localized to the cortex, while CBD and PSP both displayed a more equitable distribution of tau between the two regions, with CBD samples frequently displaying a higher tau burden than PSP in both regions. This evidence concerns the gene MAPT and Alzheimer disease.