APOE and early-onset autosomal dominant Alzheimer disease: Previously, blood analysis revealed a significant association between longer TOMM40 poly-T lengths and neuroimaging higher medial temporal cortex plaque and NFT burden in non-demented older adults.121  TOMM40 ‘523 polymorphism affects expression levels of APOE, and TOMM40 mRNAs in the temporal and occipital cortices of late-onset Alzheimer disease and non-demented controls.122 The molecular and biochemical mechanism(s) underlying the effect of increased TOMM40 expression upon Alzheimer disease pathophysiology remains to be investigated.