Moreover, several genes that encodes to protein-related cholesterol homeostasis, including ApoE, CYP46A1, ACAT1/SOAT1, the cholesterol efflux transporters ABCA1 and ABCA7, and LRP1 have been linked to the risk, development or progression of AD (Chen et al., 2008; Kim et al., 2009; Di Paolo and Kim, 2011). The gene discussed is ABCA1; the disease is Alzheimer disease.