We spatially multiplexed the proteome geography at two levels of the cortex and the subcortical white matter in patients with various types of dementia (Alzheimer’s disease, C9orf72, MAPT also referred to as FTLD-tau, FTLD-TDP, FTLD-GRN; n = 6 per syndrome) and neurologically healthy controls (NHC). Here, C9orf72 is linked to early-onset autosomal dominant Alzheimer disease.