TREM2 and mood disorder: Notably, ten of these genes (i.e., SLC7A5, SLC1A2, NPBWR1, APOL1, QPRT, LRG1, PRPH, GRIK5, TREM2, and MCHR1) are known to influence neural cell function and to be associated with behavioral traits and neuropsychiatric diseases, such as mood disorders and schizophrenia (Shao and Vawter, 2008).