Additional research is needed to explore the mGluR5 SUMO relationship and determine if mGluR5 inhibitors used for AD, such as memantine HCl (Namenda), 2-chloro-4-((2,5-dimethyl-1-(4-(trifluoromethoxy)phenyl)-1H-imidazol-4-yl)ethynyl)pyridine (CTEP), or basimglurant, may similarly ameliorate FXTAS-related cognitive decline and pathology. This evidence concerns the gene GRM5 and Alzheimer disease.