A growing number of studies have suggested that the nAChR is related to nicotine addiction, cognition, depression, hyperactivity disorder, cancer, and AD (Sarter et al., 2009; Schaal et al., 2015; Laikowski et al., 2019; Ma and Qian, 2019); therefore, ARMCX3 may promote the progression of these diseases. This evidence concerns the gene ARMCX3 and major depressive disorder.