Taken together with the evidence in humans, it appears that the effects of APOE-ε4 genotype on AD-related neuropathology and its clinical manifestation of memory impairment are exacerbated by physical inactivity. Indeed, PA does not have greater effects in ε4 carriers when compared to non-carriers, but rather these associations tend to be greater in physically active ε4 carriers compared to sedentary ε4 carriers. This evidence concerns the gene APOE and Alzheimer disease.