However, since the first report of cerebellar symptoms caused by mGluR1 antibodies in humans in 2000, only 39 cases of anti-mGluR1 encephalitis have been documented (Smitt et al., 2000; Marignier et al., 2010; Lancaster et al., 2011; Iorio et al., 2013; Lopez-Chiriboga et al., 2016; Yoshikura et al., 2018; Pedroso et al., 2018; Christ et al., 2019; Gollion et al., 2019; Chaumont et al., 2019; Spatola et al., 2020; Bien et al., 2020; Chandler et al., 2022; Wang et al., 2023; Vinke et al., 2022; Goh et al., 2022; Chen et al., 2024). This evidence concerns the gene GRM1 and viral encephalitis.