For example, slower rates of hippocampal atrophy and higher levels of CSF Aβ were recently detected in cognitively normal older APOE ε2 carriers (N = 27 APOE ε2/ε2 or ε2/ε3, versus N = 107 APOE ε3/ε3) (Chiang et al., 2010); Relative to Aβ+ ɛ4 noncarriers (N = 36), Aβ+ ɛ4 carriers (N = 48) showed significantly faster decline on memory tasks (Lim et al., 2015). This evidence concerns the gene APOE and hippocampal atrophy.