RGS12 and major depressive disorder: As inflammation can significantly impact the pathophysiology of bipolar disorder [77], including alterations in microglial activity being linked to mood regulation and neuroplasticity [78], a change in the interaction between RGS12 and CXCR2, given the R59Q variation, may influence the microglial and/or global immune system responses, potentially affecting the cytokine profiles and neuronal signaling pathways crucial to the development and exacerbation of bipolar disorder symptoms (e.g., depression, as reviewed in [79]).