TBR1-related disorder is caused by changes (also known as variants or mutations) in the TBR1 gene. The TBR1 gene has multiple roles in the genetic control of cerebral development and functioning. It allows the production of the TBR1 protein, which is a brain-specific factor particularly expressed in the cerebral cortex. TBR1 regulates the expression of several genes associated with intellectual disability (ID) and autism spectrum disorders.
TBR1-related disorder is caused by “loss of function variants”, meaning that the mutation in the gene prevents the production of a functional protein, and consequently disrupts brain development and function.
All the reported TBR1 variants occurred de novo (except for one individual for which it can be verified as a result of sperm donation), meaning it was a new variation in the child, not inherited from one parent.
Currently, there is no known correlation between the type and the localization of the variation in the gene, and the severity of the patient’s signs.
TBR1