Although female rats spent more time in open arms than their male conspecifics (SDAY1: F1,87 = 11.405, p = 0.001, GxSDAY1: F2,87 = 0.325, p = 0.724, Figure 7C’), the anxiogenic effect of SERT deficiency was robust and SERT−/− rats of both sexes displayed more anxiety-related behavior than their SERT+/+ littermates (p = 0.002 and p = 0.005, respectively). This evidence concerns the gene SLC6A4 and Anxiety.