Similarly, in our group’s previous work, both observationally and genetically determined low plasma levels of C-reactive protein were associated with high risk of AD.33 A mechanistic explanation could be that low C-reactive protein levels lead to decreased opsonization, decreased phagocytosis of Aβ by microglia, and decreased activation of the complement system, resulting in compromised Aβ elimination. The gene discussed is CRP; the disease is Alzheimer disease.