To investigate how the levels of p-tau Ser356 change with Braak stage in postmortem human temporal cortex (BA20/21), soluble fractions of total homogenate and synaptoneurosome preparations were generated from frozen postmortem brain from ten Braak 0–I individuals, ten Braak III–IV individuals and ten Braak VI individuals (with clinically diagnosed AD). This evidence concerns the gene MAPT and Alzheimer disease.