DHCR24 and Alzheimer disease: Similarly, DHCR24-deficient mouse brains had reduced levels of membrane cholesterol, and increased APP β-cleavage and Aβ production by disorganized cholesterol-rich lipid rafts, which showed similar reduction of membrane cholesterol than that reported in the AD patients (Abad-Rodriguez et al., 2004; Crameri et al., 2006; Ledesma et al., 2012).