Decreased expressions of complexin 2 have also been associated with neurodegenerative diseases including Alzheimer’s, Huntington’s, and Parkinson’s; psychiatric disorders including schizophrenia and bipolar disorder [37,38,39,40], with seizures and epilepsy being common comorbidities [41,42,43,44,45,46]. Here, CPLX2 is linked to bipolar disorder.