However, dissimilar to the previous studies on Grin2b mice largely analyzing the synaptic and behavioral impacts of a homozygous Grin2b deletion, GRIN2B mutations identified in human brain disorders are preponderantly heterozygous mutations, and synaptic and behavioral phenotypes of heterozygous Grin2b-mutant mice remain largely unexplored. The gene discussed is GRIN2B; the disease is brain disorder.