GRIN2B-related neurodevelopmental disorder
# GRIN2B-related neurodevelopmental disorder

GRIN2B-related neurodevelopmental disorder is a rare neurodevelopmental disorder which is characterized by developmental delays and intellectual disabilities of variable degrees, muscle tone anomalies, feeding difficulties, and behavioral problems.

## Signs and symptoms

The following list comprises most of the symptoms people with GRIN2B show:

* Intellectual disability (mild to severe)
* Developmental delay (mild to severe)
* Hypotonia
* Epilepsy
* Autism spectrum disorder
* Autistic-like behavior
* Microcephaly
* Hyperactivity
* Stereotypy
* Spasticity
* Feeding difficulties

Less common symptoms include:

* Visual impairment
* Dystonia
* Dyskinesia
* Other choreiform movement disorder

## Causes

This condition is caused by mutations in the GRIN2B gene, located in chromosome 12.

This gene makes instructions into how to make a protein called GluN2B, a type of NMDA receptor, which is found in brain neurons during ante-natal brain development. It is involved in correct brain development and function, regulating memory, synaptic plasticity and the ability of learning.

## Epidemiology

Around 100 cases have been described in medical literature.

