With studies in mice overexpressing hAPP, it is shown that ABCA1 deficiency increases Aβ40:Aβ42ratio.28A decrease in ABCA1 causes greater accumulation of amyloid, increasing ABCA1 protein or function decreases amyloid accumulation.4In the study by Kim et al (2013), it was found that neuronal ABCA1 mRNA and protein levels in the hippocampus of the brains of AD patients were not affected and were significantly upregulated compared with the cerebellum.4The authors thought that this upregulation was related to the pathological process of AD. The gene discussed is ABCA1; the disease is Alzheimer disease.