Although ACC has demonstrated a negative association in volume and resting state activity with rumination (52), and 5-HT2A binding in ACC has been negatively related to treatment resistance in major depression (53), the exact role of rs3125 in HTR2A expression and the role of miRNA-regulated HTR2A expression in brooding have to be elucidated in the future. This evidence concerns the gene HTR2A and major depressive disorder.