ABCA1 and early-onset autosomal dominant Alzheimer disease: Kim et al. demonstrated that miR-33 regulates ATP-binding cassette transporter A1 (ABCA1) which regulates ApoE lipidation, and this in turn has an effect on Ab levels in the brain and showed the role that dysregulation in the metabolism of Ab may have in the pathogenesis of Alzheimer's disease which may be similar to the role that Ab-induced upregulation of miR-33 in the retina/RPE plays in AMD pathogenesis [98].