N-methyl-D-aspartate (NMDA) receptors are glutamate-activated ion channels found at excitatory synapses throughout the brain. They play an important role in various processes in the brain such as excitatory neurotransmission and synaptic plasticity. NMDA receptors are composed of multiple subunits including at least one NR1 subunit, one or more NR2 subunits and occasionally an NR3 subunit. The NR2 subunits are encoded by the GRIN2A-D genes. NR2 subunits are expressed differentially across various cell types and are important for the control of electrophysiological properties of the NMDA receptor. Genetic variation in either the GRIN2A or GRIN2B genes has been implicated in various neurodevelopmental disorders, such as epilepsy, mental retardation and encephalopathy.
The GRIN2A gene (14 exons) spans ~430 kb of genomic DNA and is located on chromosome 16p13.2, about 10 Mb from the p-telomere. The GRIN2B gene (13 exons) spans ~420 kb of genomic DNA and is located on chromosome 12p13.1, about 14 Mb from the p-telomere. This P410-A1 probemix contains 17 probes for the GRIN2A gene, covering all exons with the exception of exon 2b. In addition, 16 probes for GRIN2B are included covering all exons with the exception of exon 6. Finally, 9 references probes are included in this probemix, detecting several different autosomal chromosomal locations.