The GRIN2B SNP (rs7301328) has been linked to bipolar disorder [24], schizophrenia, and other neuropsychiatric disorders; however, to the best of our knowledge, few studies have investigated the influence of the GRIN2B SNP (rs7301328) at the molecular level, including its effect on NMDAR function or on the level of GRIN1 or GRIN2 expression. This evidence concerns the gene GRIN1 and bipolar disorder.