Female APOE-4 carriers are more likely than male carriers to develop AD, with a nearly 4- and 10-fold in women with one and two APOE-4 alleles, respectively, whereas men exhibit essentially little increased risk with one APOE-4 allele and a fourfold increased risk with two APOE-4 alleles (Farrer et al., 1997; Altmann et al., 2014; Ungar et al., 2014). The gene discussed is APOE; the disease is Alzheimer disease.