A TCF7L2-related disorder is caused by a change in one copy of the TCF7L2gene.
All mutations identified so far have arisen by chance (de novo), meaning that they are not inherited from the parents.
The TCF7L2gene provides instructions for making a protein that controls the activity of many other genes important for the brain’s development before and after birth.
Most affected individuals have mutations that either shorten the protein or change a critical region of it, both of which prevent the gene from working correctly. As a result, cells lack sufficient functional TCF7L2 protein. This reduced gene activity is believed to disturb brain development, leading to the disorder.
TCF7L2