GRM3 and early-onset autosomal dominant Alzheimer disease: In order to further test the hypothesis that a group II mGluR, specifically mGluR3, mediates the procognitive efficacy of GCPII inhibitors, these compounds were tested across a series of animal models that included short- and long-term novel object memory, Alzheimer’s disease, and acute alcohol intoxication, using a group II antagonist in wild type mice and testing mice that are null mutant for mGluR2 and mGluR3.