Similarly, we do not understand the modest elevation of octadecanoic (stearic) acid in the brains of Tg2756_DSP4 mice, but note its concordance with observations in autopsy studies of Alzheimer's disease [79] as well as to a report of its ability to induce hyperphosphorylation of tau in an experimental system [80]. This evidence concerns the gene MAPT and Alzheimer disease.