Translational research: Rett syndrome and tuberous sclerosis complex.

PURPOSE OF REVIEW: Rare genetic diseases that affect behavior and cognition provide a unique opportunity to study the mechanisms of neurodevelopmental disorders through the examination of animal models, which can lead to development of hypotheses and treatments testable in human beings. Rett syndrome (RTT) and tuberous sclerosis complex (TSC) are both Mendelian disorders that present with autism, epilepsy, and intellectual disability, in which animal model work has been directly translated into clinical treatment trials currently underway. Here, we review the recent advances in our understanding of RTT and TSC pathogenesis and signaling pathways that may be targeted for novel treatments. RECENT FINDINGS: Animal models generated by engineering mutant forms of the mouse homologs of human genes involved in RTT and TSC have allowed dissection of the molecular pathology. They have further acted as in-vivo assays of potential therapeutic strategies that have translated to human clinical trials. SUMMARY: Single-gene disorders associated with neurodevelopmental disorders provide powerful model systems to study the roles of individual molecules and associated signaling pathways in the genesis of autism, epilepsy, cognitive impairment, and neuropsychiatric symptoms. These diseases are leading to disease-modifying human therapies that may eventually translate to wider therapeutic strategies for autism.