The N-methyl-D-aspartate receptor (NMDAR) is a type of ionotropic glutamate receptor mainly expressed on neurons in the central nervous system. It is composed of NR1, NR2 (A-D), and NR3 subunits, forming a heterotetrameric structure responsible for NMDAR function. NMDAR plays a crucial role in processes such as synaptic plasticity, learning, and memory, with its activation leading to calcium influx into neurons and triggering downstream signaling pathways. The specific expression and mutations of NMDAR genes are associated with various neurological and psychiatric disorders, including Alzheimer's disease, schizophrenia, and depression.