GRIN2B

Pathogenic changes in the GRIN2B gene have been associated with several neurodevelopmental disorders, including intellectual disability, epilepsy, autism spectrum disorder (ASD), and attention deficit hyperactivity disorder (ADHD). These conditions can range in severity, affecting cognitive, motor, and social development to varying degrees. The symptoms and their intensity can vary widely among individuals with GRIN2B-related disorders.
In the context of genetic research and neurology, GRIN2B variants are of significant interest because they provide insights into the molecular basis of many complex neurological conditions. Understanding how these variants alter NMDA receptor function can help in developing targeted therapies to mitigate the symptoms of disorders associated with GRIN2B. Currently, treatments are largely symptomatic and may include behavioural therapies, educational support, and medications to manage specific symptoms such as seizures or mood disorders.

GRIN2B SYMPTOMS

In a 2019 survey of patients with GRIN 2B conducted by the GRIN 2B Foundation 90% of respondents reported the following symptoms:

  • Hypotonia (low muscle tone) 
  • Gross and fine motor delays and disabilities 
  • Cognitive delays and disabilities 
  • Non-verbal and or limit speech communication 

 

Additional symptoms or behaviours reported by parents of children with GRIN2B, from most common to least common include: 

  • Developmental/Behavioural Symptoms and Characteristics such as self-care assistance; sensory seeking behaviours; behavioural problems (anxiety, mood swings, etc.); problems sleeping; tires easily; arm/hand flapping/other movement disorders; likes strange noises; drooling; poor eye contact; sensory avoiding behaviours; self-harming behaviours; repetitive movements and/or tics; short-term memory issues; non-ambulatory; hand wringing; echolalia
  • Seizures. About one third of the surveyed individuals have experienced seizures. The following seizure types have been observed: Complex; Unknown seizure type; Grand Mal; Simple; Spasm; Absence; Atonic; Drop/Gelastic seizure; Multifocal Generalised Epilepsy. About two thirds of the surveyed individuals did not experience seizures. Of those, just under half show irregular brain activity on their EEG.
  • Other Neurological Symptoms and Characteristics including: Clumsiness; Small head size; Cerebral Palsy; High muscle tone (Hypertonia); Large head size; Brain malformations. 
  • Vision Symptoms and Characteristics including: Strabismus; Near-sighted; Nystagmus; Farsighted; Cortical blindness/Cortical vision impairment; Exotropia
  • Feeding/Gastrointestinal Symptoms and Characteristics: Constipation; Reflux; Can eat only soft/pureed food; Chokes or gags easily; Tube fed; Diarrhoea; Vomits easily
  • Other Physical Issues: Difficulty gaining weight; Hypermobility/Loose joints; Recurrent chest infections; Scoliosis; Short stature; Hip dysplasia
  • Other Medical Diagnoses Respondents Received: Intellectual disability; Epilepsy; Autism Spectrum Disorder; Attention Deficit/Hyperactivity Disorder

GRIN gene family

GRIN2A

The impact of GRIN2A can vary greatly among individuals, with some experiencing severe symptoms and others having milder effects. Treatment often focuses on managing symptoms, especially seizures, through medication and supportive therapies. Since GRIN2A-related disorders can significantly affect communication and cognitive development, speech therapy and special educational support are also

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GRIN2C

Pathogenic changes in the GRIN2C gene can lead to various neurological and psychiatric conditions, although they are less commonly reported than variants in some of the other NMDA receptor subunit genes, like GRIN2A and GRIN2B. The conditions associated with GRIN2C variants might include developmental delay, intellectual disability, epilepsy, and potentially

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GRIN2D

Changes in the GRIN2D gene have been less frequently reported in comparison to variants in other NMDA receptor subunit genes but can be associated with various neurological disorders. These might include developmental delays, intellectual disability, epilepsy, and other conditions affecting the nervous system. The specific role of GRIN2D variants in

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GRIN1

GRIN1 SYMPTOMS Some of the most common health issues and symptoms among GRIN1 patients, as reported by parents of patients in 2019.  Common  Intellectual disability / global developmental delay Epilepsy / seizures (from birth, or may develop later) Muscular hypotonia (low tone that can cause feeding difficulties and/or constipation) Cortical

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