In marked contrast to carriers of both APOE4 and BCHE-K, noncarriers of these alleles displayed less hippocampal atrophy and an amnestic deficit-sparing phenotype, with the lowest levels of amyloid pathology, the highest levels of neuroaxonal injury, and high levels of ventricular expansion (Table 2). The gene discussed is APOE; the disease is hippocampal atrophy.