2000). In support, a more recent study observed that in the early postnatal brain, a number of neurons with reduced tau levels that reached the cortical plate exhibited underdeveloped dendrites and a striking reduction in connectivity as evidenced by the size of their boutons (Sapir et al. 2012). The authors concluded that MAPT may be a dosage‐sensitive gene involved in intellectual disability. The gene discussed is MAPT; the disease is Intellectual disability.