APOE and Alzheimer disease: Additionally, DAM exhibit an upregulation of genes associated with lysosomal, phagocytic, and lipid metabolism pathways, including several well-known AD risk factors such as cathepsin D (CtsD), Trem2, TYRO protein tyrosine kinase-binding protein (Tyrobp), lipoprotein lipase (Lpl), and apolipoprotein E (ApoE).