Cntnap2, or contactin associated protein like 2, encodes a single transmembrane protein with 1331 amino acid residues. It is specifically expressed in the nervous system and plays versatile roles in axonal organization, synaptic functions, neuronal migration, and functional connectivity [2,7]. CNTNAP2 has been widely investigated as a risk gene for multiple neurodevelopmental disorders, including autism spectrum disorders (ASD), epilepsy, and others [1,2,4,5,6]. Mouse models based on human disease-causing mutations in Cntnap2 provide the potential for understanding its gene function and for developing novel treatments [1].

Cntnap2 knockout (KO) mice exhibit deficits in the three core ASD behavioral domains, hyperactivity, and epileptic seizures, paralleling human phenotypes with CNTNAP2 mutations. Neuropathological and physiological analyses before seizure onset in these mice show neuronal migration abnormalities, a reduced number of interneurons, and abnormal neuronal network activity [1]. Virally delivering the CNTNAP2 intracellular domain (CICD), produced by γ-secretase cleavage, to the medial prefrontal cortex of Cntnap2-deficient mice normalizes ASD-related behavioral deficits [2]. Oxytocin administration to Cntnap2 KO mice rescues social deficits, normalizes connectivity patterns, and restores oxytocin immunoreactivity in the paraventricular nucleus of the hypothalamus [3,5]. Intragenic deletions of CNTNAP2 may disrupt its ability to bridge the intercellular space between neurons, potentially contributing to neuronal hypoconnectivity in neurodevelopmental disorders [4].

In conclusion, model-based research reveals that Cntnap2 is crucial for proper brain development and normal neuronal function. Cntnap2 KO mouse models have significantly contributed to understanding the role of Cntnap2 in ASD and other neurodevelopmental disorders, providing new tools for mechanistic and therapeutic research in these disease areas [1,2,3,4,5].