CNTNAP4 and Alzheimer disease: ,35 Furthermore, we and other groups demonstrated that deletion of Cntnap4 or CNV polymorphisms of CNTNAP4 cause neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer's disease (AD), and neurological disorders, such as epilepsy.36, 37, 38 Because GABAergic signalling in the amygdala is closely associated with the consolidation and extinction of fear memory,39 we speculated that Cntnap4 may also play a role in fear memory processing.