Behavioral phenotype in five people with de novo mutations within the GRIN2B gene

Original research article by I. Freunscht et al. (2013)

Read the article here.

The researchers used questionnaires to develop behavioral profiles for five children and adolescents with GRIN2B gene changes. All five had some level of intellectual disability (ID), ranging from mild to severe. Four of the five walked at around 2 years of age, and one walked at closer to 3 years of age. None of the five study participants had a history of seizures, although three had a history of abnormal EEGs.

The researchers used data from the Developmental Behavior Checklist completed by the children’s parents and teachers. The authors concluded that “although specific facial dysmorphism and [birth defects] are usually absent in people with GRIN2B changes, there does seem to be a characteristic behavioral [pattern of features] consisting of ID, hyperactivity, impulsivity and distractibility. Stereotypic and stimulatory behavior, sleeping problems and a friendly but boundless social behavior also appear to be associated features.”

GRIN2B gene changes are now recognized as a cause of intellectual disability. Changes in this gene are thought to occur in about 0.5% – 1% in people with ID. Although intellectual disability has been associated with changes in this gene, little information has been gathered about life skills and other areas of strength and weakness in children with this genetic change.