CIITA and major depressive disorder: Earlier researches have also reported that the SNX29 gene is one of the translocation partners involved in the major histocompatibility complex class II transactivator CIITA (MHC2TA) in human KH-H2 cells (15) and is strongly associated with schizophrenia (16), intelligence (17), bipolar disorder (BPD) as well as major depressive disorder (MDD) (18).