Of the pre- and postsynaptic protein-encoding genes upregulated in Braak Stages III and IV compared with I/II, GRIN2A mRNA is also elevated in the hippocampus in MCI compared with NCI103 suggesting a target for intervention.104 Microarray studies also reveal VAMP1 mRNA elevation in the superior frontal gyrus and increased hippocampal STXBP5L mRNA in MCI compared to NCI, while both are decreased in entorhinal cortex,103 suggesting differential brain regional vulnerability between aging and the onset and progression of Alzheimer disease. This evidence concerns the gene STXBP5L and early-onset autosomal dominant Alzheimer disease.