Based on these data, this study compared the efficacy of the initial lead compound AFC03127 with the mGluR5 inhibitor 2-Methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP) and the GSK3 inhibitor SB216763 in Fmr1KO mice with the goal of identifying a more efficacious compound indicated for FXS. The gene discussed is GRM5; the disease is fragile X syndrome.