The release of intracellular calcium is temporally delayed by reducing the expression of the 5‐HT2C receptor (Chagraoui et al, 2016), and the mRNA expression level of 5‐HT2C was decreased in SSRI‐resistant MDD patients‐derived forebrain neurons (Vadodaria et al, 2019a), which aligns with our results. This evidence concerns the gene HTR2C and major depressive disorder.