GRI Disorders (GRIA, GRID, GRIK, GRIN)

What are GRI disorders?  

GRI disorders are a group of rare neurogenetic disorders that can cause epilepsy, autism, intellectual disability, movement disorders and behavioral problems.  

What causes GRI disorders? 

GRI disorders are caused by a DNA change (mutation) in one of the ionotropic glutamate receptor genes. These genes play a vital role in brain function. Sometimes these differences can be inherited, meaning they are passed down from a child’s parent, but most of these differences occur randomly without any link to family history (de novo). 

Types of GRI disorders 

Our experts treat children with many GRI conditions, including: 

• GRIN: Caused by a change in one of seven GRIN genes, including GRIN1, GRIN2A, GRIN2B and GRIN2D 
• GRIA: Caused by a change in one of four GRIA genes, including GRIA1, GRIA2, GRIA3 and GRIA4 
• GRIK: Caused by a change in one of five GRIK genes, including GRIK1, GRIK2, GRIK3, GRIK4 and GRIK5 
• GRID: Caused by a change in one of four GRID genes, including GRID1 and GRID2 

Who gets GRI disorders? 

A child is born with a mutation in one of their GRI genes, with symptoms showing up in infancy or childhood.   

What are the signs and symptoms of GRI disorders?  

While the signs and symptoms can be different for each child, they can include: 

• Behavioral issues (anxiety, aggression, outbursts, etc.) 
• Developmental delays 
• Digestion issues 
• Epilepsy (seizures) 
• Learning disabilities 
• Low muscle tone (hypotonia) 
• Movement disorders (tremors, balance problems or other involuntary muscle movements )  
• Paroxysmal sympathetic hyperactivity (neuro storms) 
• Sleep disturbances 
• Speech delays 

What tests do we use to diagnose GRI disorders? 

A genetic test using blood, saliva or a cheek swab sample can show changes in the GRI genes.  

How are GRI disorders treated? 

Because of their genetic nature, there’s no cure for GRI disorders. At Children's Hospital Colorado, our treatments are designed to help alleviate your child's symptoms and to create the best possible quality of life for them. We see people of all ages with GRI disorders in our GRI Clinic and have extensive experience working with all different types of GRI disorders. 

Neuropsychologic testing: Also called cognitive testing, this includes a series of tasks to see how a child’s brain is working, specifically in relation to the world around them. Through these tests, we can better understand how your child learns and can help guide your child’s school, therapists or outside care team to give them the best support possible. With our specialized team, we can help compare and contrast results to other children with the same genetic changes as your child and identify ways to support their development. 

Some treatment options may include medications to address seizures, sleep problems, muscle tone and behavioral issues. We also use physical, occupational and speech therapy to address motor and communication delays. These supportive treatments help most children adjust to the symptoms of GRI disorders.  

Why choose us for treatment of GRI disorders?  

Our GRI Clinic and Neuroscience Institute at Children’s Colorado are international leaders in the diagnosis and treatment of rare genetic disorders such as GRI conditions. We bring together experts such as therapists, sleep therapists, developmental pediatric specialists, geneticists, special care clinicans, social workers and more to work with each family to meet their child’s specific needs. Through research and innovation, our teams can provide the most up-to-date care. We also have options for clinical trials if your child and family are interested. With so many specialties, experts and innovative treatments under one roof, we provide care that is both effective and convenient.  

Helpful resources 

• GRIN2B Foundation  
• CureGRIN Foundation 
• National Organization for Rare Disorders