What are GRIN disorders?
GRIN disorders are a group of rare genetic conditions that cause a variety of physical and intellectual symptoms. These symptoms can be life-threatening.
What are the symptoms of GRIN disorders?
Some of the most common symptoms of these conditions include:
- Intellectual disability
- Developmental delay
- Limited/non-verbal communication
- Low muscle tone
- Issues with the gastrointestinal system
- Cortical visual impairment
- Limited mobility
- Feeding difficulties
What causes GRIN disorders?
One of seven genes must be mutated in order for one to be affected by a GRIN disorder. These genes include GRIN1, GRIN2A, GRIN2B, and GRIN2D. The similarity between these genes is that they all play a role in creating NMDA receptors, which are necessary in memory and learning. The majority of these mutations happen sporadically, meaning that they are not inherited from a parent. In those that are inherited, the mutation is passed down in an autosomal dominant pattern.
How are GRIN disorders diagnosed?
Obtaining a diagnosis for these disorders can be difficult, as they are often misdiagnosed as autism, Angelman syndrome, cerebral palsy, or other genetic disorders. Parents often suspect that something is wrong when children begin to miss developmental milestones. A diagnosis can be confirmed through genetic testing.
What are the treatments for GRIN disorders?
There is no cure for GRIN disorders; treatment is supportive and symptomatic. Physical, occupational, and speech therapy are recommended. Antiepileptic medication is often necessary as well. It is important to remember that not all those who are affected present the same symptoms, so treatment should be tailored for each individual.