MAPT and Alzheimer disease: The most common genetic risk factor for non-autosomal dominant Alzheimer’s disease, the APOE e4 gene, has been associated with more severe tau-related neurodegeneration22 and clinical rates of progression.23BIN1, which is one of the most significant genetic risk factors for Alzheimer’s disease, has also been clearly linked as a modulator of tau pathology24 and an intermediate of tau pathology propagation.25 It seems likely that other genes, or combinations of genes, may impact various aspects of tau pathobiology as well.