GRM1 and autosomal dominant cerebellar ataxia: Testing for spinocerebellar ataxia (SCA; types 1, 2, 3, 6, 7 and 17), Friedreich’s ataxia (FRDA), and fragile-X tremor-ataxia syndrome (FXTAS) has been carried out in one patient with mGluR1 antibodies and was negative [36].