APOE ε4 allele is strongly associated with Aβ pathology in human AD brains, with homozygous carriers having the highest Aβ burden (Polvikoski et al., 1995; Premkumar et al., 1996; Bertram et al., 2007; Reiman et al., 2009; Mishra et al., 2018). The gene discussed is APOE; the disease is Alzheimer disease.