While the enhanced activity of mGluRs in the absence of FMRP upregulates the translation of STEP [178,180,181] in the hippocampus of the Fmr1 KO mouse, genetic reduction of STEP significantly diminishes some FXS-associated behaviors in Fmr1 KO including seizures and restores select social and nonsocial anxiety-related behaviors [181]. The gene discussed is FMR1; the disease is fragile X syndrome.