GRIA2-Related Syndrome

GRIA2-related syndrome happens when there are changes in the GRIA2 gene. These changes can keep the gene from working as it should.

Each family is different. A geneticist or genetic counselor can give you advice on the chance that this will happen again in your family.

The risk of having another child who has GRIA2-related syndrome depends on the genes of both birth parents.

• If neither birth parent has the same gene change found in their child, the chance of having another child who has the syndrome is on average 1 percent. This 1 percent chance is higher than the chance of the general population. The increase in risk is due to the very unlikely chance that more of the mother’s egg cells or the father’s sperm cells carry the same change in the gene.
• If one birth parent has the same gene change found in their child, the chance of having another child who has the syndrome is 50 percent.

For a symptom-free sibling, a brother or sister, of someone who has GRIA2-related syndrome, the risk of having a child who has the syndrome depends on the symptom-free sibling’s genes and their parents’ genes.

• If neither parent has the same gene change found in their child who has the syndrome, the symptom-free sibling has a nearly 0 percent chance of having a child who has GRIA2-related syndrome.
• If one birth parent has the same gene change found in their child who has the syndrome, the symptom-free sibling has a small chance of also having the same gene change. If the symptom- free sibling has the same gene change as their sibling who has the syndrome, the symptom-free sibling’s chance of having a child who has GRIA2-related syndrome is 50 percent.

For a person who has GRIA2-related syndrome, the risk of having a child who has the syndrome is about 50 percent.

As of 2024, at least 39 people with GRIA2-related syndrome have been identified in the medical literature.

People who have GRIA2-related syndrome might not look very different. Some people have a smaller than average head size.

Scientists and doctors have only just begun to study GRIA2-related syndrome. At this point, there are no medicines designed to treat the syndrome. A genetic diagnosis can help people decide on the best way to track the condition and manage therapies. Doctors can refer people to specialists for:

• Physical exams and brain studies
• Genetics consults
• Development and behavior studies
• Other issues, as needed

A developmental pediatrician, neurologist, or psychologist can follow progress over time and can help:

• Suggest the right therapies. This can include physical, occupational, speech, or behavioral therapy.
• Guide individualized education plans (IEPs).

Specialists advise that therapies for GRIA2-related syndrome should begin as early as possible, ideally before a child begins school.

If seizures happen, consult a neurologist. There are many types of seizures, and not all types are easy to spot. To learn more, you can refer to resources such as the Epilepsy Foundation’s website: epilepsy.com/…t-is-epilepsy/seizure-types

There are few research publications on people with GRIA2-related syndrome. The information below includes 33 people. The oldest person included was 31 years old.

All people had intellectual disability or developmental delay ranging from mild to severe, 24 people had moderate intellectual disability, and 9 people had severe intellectual disability. Many people had autism, and one-half had seizures. Seizure control through medication was difficult.

• 33 out of 33 people had intellectual disability (100 percent)
• 15 out of 33 people had seizures (45 percent)
• 2 out of 12 people took medication that controlled their seizures (17 percent)

Many people had autism, and 5 people had obsessive-compulsive disorder or repetitive traits. One person with GRIA2-related syndrome had self-harming behavior.

• 17 out of 21 people had autism (81 percent)

Speech was a problem for most people and regression of language abilities was reported. Some people had brain changes observed on magnetic resonance imaging (MRI). Most people had a head size that was smaller than average (18 out of 21, 86 percent). Only a few people had the clinical diagnosis of microcephaly.

• 25 out of 33 people had delayed or absent speech (76 percent)
• 8 out of 23 people had findings on MRI (35 percent)
• 4 out of 29 people had a clinical diagnosis of microcephaly (14 percent)

Some people had movement issues: 4 people were unable to walk and 3 people had movement issues, such as ataxia, dystonia, or spasticity.

• 6 out of 33 people had movement issues (18 percent)

CureGRIN Foundation

CureGRIN Foundation is dedicated to improving the lives of people around the world with GRI Disorders (GRIA, GRID, GRIK, and GRIN) and their families through research, education, and support. We work closely with scientists and the medical community to drive patient-centered research that will lead to treatments and cures. ​

• Learn more: www.curegrin.org

Simons Searchlight

Simons Searchlight is an online international research program, building an ever growing natural history database, biorepository, and resource network of over 175 rare genetic neurodevelopmental disorders. By joining their community and sharing your experiences, you contribute to a growing database used by scientists worldwide to advance the understanding of your genetic condition. Through online surveys and optional blood sample collection, they gather valuable information to improve lives and drive scientific progress. Families like yours are the key to making meaningful progress. To register for Simons Searchlight, go to the Simons Searchlight website at www.simonssearchlight.org and click “Join Us.

• Learn more about Simons Searchlight:
  • www.simonssearchlight.org/frequently-asked-questions
•  Simons Searchlight webpage with more information on GRIA2
  • www.simonssearchlight.org/research/what-we-study/gria2