We found that APBA1/2 related with amyloid beta A4 precursor protein (APP) metabolism in AD [17–19] was correlated with 5-HT6R in depression patients, and regulated by 5-HT6R in the AD mouse model, suggesting significant implications for the network of 5-HT6R between AD and depression. This evidence concerns the gene HTR6 and depressive symptom measurement.