DIP2C and major depressive disorder: In the overlapping results of our first-episode, drug-naive adolescents with MDD and GEO data, DIP2C has been proven to play an important role in brain development and function (40), and studies have found that when the maternal circadian rhythm was disturbed, the expression of DIP2C methylation in the placenta was up-regulated, which might have an impact on the fetus (41).