TMEM165 and depressive disorder: Based on pivotal role of TMEM165 in a calcium/proton transporter protein, importance of calcium ions in nerve conduction and the immune modulation, and the relation of immune system dysfunction with depressive disorder, as well as the relation between N-glycosylation and mental and neurological disorder, it is not unexpected that rs534654 variant of this gene is associated with risk of BD, and impairment in this gene may increase the risk of BD.