ABCA1 and Alzheimer disease: The connection between AD and lipid metabolism is supported by multiple risk factors for late-onset AD that include lipid metabolism-related genes, such as apoE, apoJ, PICALM, ATP-binding cassette A1 (ABCA1) and A7 (ABCA7), and low-density lipoprotein (LDL) receptor protein 1 (LRP1).