Recent studies have shown a strong correlation between Aβo levels and the severity of synaptic and cognitive damage (McLean et al., 1999; Ferreira et al., 2007; Haass and Selkoe, 2007), suggesting that Aβo are the main effectors of synaptic loss and neuronal degeneration in AD (Lambert et al., 1998; Cleary et al., 2005; Cerpa et al., 2008). The gene discussed is ABO; the disease is Alzheimer disease.