Protocadherin Mutations in Neurodevelopmental Disorders

Neurodevelopmental disorders such as intellectual disability (ID), epilepsy, autism spectrum disorders (ASDs), schizophrenia (SZ), and bipolar disorder (BD) include cognitive, neurological, and/or psychiatric dysfunction and can be caused by impairment of the brain during development. These disorders are complex and highly heterogeneous and often coexist with other types of co-comorbidities. Mutations in genes encoding for cell adhesion molecules, specifically the delta-2-protocadherin (. 2-PCDH) family have been shown to be associated with a number of these disorders. These genes have crucial roles in early brain development, including neuronal migration, synaptogenesis, and axonal growth. Currently, little is known about how mutations in the protocadherin gene family contribute to the underlying pathogenesis of neurodevelopmental disorders. This review will discusses different neurodevelopmental disorders and the role of their respective associated published ?2-PCDHs mutations, in particular PCDH19, including new insights into novel mutations potentially contributing to these diseases.