The genes that are potentially of interest for the study of depression include the Neural Growth Regulator 1 (NEGR1), the glutamate metabotropic receptor 5 (GRM5), the glutamate ionotropic receptor kainate type subunit 3 (GRIK3) and the transmembrane protein 106B (TMEM106B) protein coding genes. Here, GRM5 is linked to depressive disorder.