Although we and others have shown APOE to affect AD risk in DS individuals (Deb et al., 2000; Prasher et al., 2008; Royston et al., 1996), this result has not been replicated in all studies (Margallo-Lana et al., 2004; van Gool et al., 1995). The gene discussed is APOE; the disease is Dravet syndrome.