ABCA1 and Alzheimer disease: ApoE4 is a carrier for cholesterol transport; hence an individual carrying an allele of ApoE4 is prone to developing Alzheimer's [5,6]. Many other genetic mutations of the receptors and transporters involved in cholesterol metabolism and transport, such as ATP binding cassette transporter 1 and 7 (ABCA1, ABCA7), APP have caused Alzheimer's disease [8].