Most rare variants in GluN2A were associated with epilepsy, whereas GluN2B variants were associated with intellectual disability with or without seizures.
We identified GRIN2B gain-of-function mutations as a cause of West syndrome with severe developmental delay as well as of ID with childhood onset focal epilepsy.
Mutations in the GRIN2B gene (MRD6, MIM613970) have been identified as a common cause of ID (prevalence of 0.5 - 1% in individuals with ID) associated with EEG and behavioral problems.
Sequencing of GRIN2B in 468 individuals with mental retardation revealed four de novo mutations: a frameshift, a missense and two splice-site mutations.
Sequencing of GRIN2B in 468 individuals with mental retardation revealed four de novo mutations: a frameshift, a missense and two splice-site mutations.