Thus, the APOE ε4 allele seems to impair the clearance of brain amyloid-β, leading to the accumulation of amyloid plaques and cerebral amyloid angiopathy [50, 51], which contributes to blood-brain barrier dysfunction [50], induces an exaggerated inflammatory response and neuroinflammation, and interferes with lipid metabolism and neuronal repair [50, 52]. The gene discussed is APOE; the disease is cerebral amyloid angiopathy.