APOE and Alzheimer disease: For example, it has been reported that the frequency of the ApoE ε4 allele in AGD cases was significantly lower than that in AD cases (73), the frequency of the ApoE ε2 allele in AGD cases was significantly higher than that in normal controls (19) and the neocortical Aβ load in AGD cases was significantly lower than that in AD cases (70, 72).