Intriguingly, deletion of Bace1 in 12-month-old heterozygous AD knock-in mice (Bace1fl/fl;Olig2-Cre; AppNL−G−F/wt mice) caused a significant reduction of amyloid plaques by ~ 33% in the hippocampus and ~ 29% in the cortex compared to age-matched AD mice (Bace1fl/fl;AppNL−G−F/wt). The gene discussed is BACE1; the disease is Alzheimer disease.