SNP Shot: Genomic Insights

GRIN2B-related neurodevelopmental disorder is a condition impacting the nervous system. It falls under the category of neurodevelopmental disorders, which arise from compromised development of the central nervous system (the brain, spinal cord, and connecting nerves). These disorders commonly impact learning, memory, and behavior, and can be linked to other neurological issues.

People with GRIN2B-related neurodevelopmental disorder experience intellectual disability ranging from mild to severe, along with delays in speech and motor skills, such as sitting and walking. Some may never develop speech or independent walking abilities. Many individuals also exhibit low muscle tone (hypotonia), hindering motor skill development and potentially causing feeding difficulties. Conversely, some individuals experience abnormal muscle stiffness (spasticity), which can also impair movement.

Approximately half of those with GRIN2B-related neurodevelopmental disorder experience recurrent seizures (epilepsy). Around 25% display characteristics of autism spectrum disorder, characterized by difficulties in communication and social interaction. Additionally, individuals may exhibit hyperactivity, impulsivity, or attention deficits, and some are noted for being overly friendly. Sleep disturbances are also a possible feature of this condition.

Less frequently, GRIN2B-related neurodevelopmental disorder may involve structural brain anomalies, an unusually small head size (microcephaly), visual impairments, and involuntary muscle movements.

Inheritance:

This condition follows an autosomal dominant inheritance pattern, meaning that a single altered copy of the gene in each cell is enough to cause the disorder. In most instances, the condition arises from new (de novo) mutations in the gene. These mutations occur either during the formation of egg or sperm cells in a parent of an affected individual or during early embryonic development. As a result, these cases typically occur in individuals with no family history of the disorder.