Expression deregulation of SHANK3 gene in children with autism spectrum disorder and attention deficit and hyperactivity disorder

Autism spectrum disorder(ASD) is a complicated neurodevelopmental disease with social communication disorder, language problem and restricted repetitive patterns and restricted repetitive patterns of behavior, activities and interests. Attention deficit hyperactivity disorder (ADHD) is a pediatric psychiatric disorder with symptoms including attention deficit, hyperactivity, and impulsiveness, which can persist into adult life. SHANK gene family encodes Shank proteins that are multidomain scaffold proteins involved in binding of the postsynaptic density in neurotransmitter receptors, ion channels and several G-protein-coupled signaling pathways. SHANK3, also known as proline-rich synapse associated protein 2 (ProSAP2), is a protein encoded by the SHANK3 gene located in human chromosome 22, play an essential role in synapse formation spine maturation and scaffold activity.

In present study the expression level of SHANK3 in ASD and ADHD patients  was assessed.

 mRNA level of the SHANK3 were evaluated in peripheral blood of 450 unrelated ASD patients, 450 unrelated ADHD patients and the normal group included 490 unrelated non-psychiatric children by quantitative RT-PCR. In addition, gene expression and their correlation with clinical symptoms were examined.

Showed mRNA level of SHANK3 gene was significantly down-regulated in ASD patients vs. normal children. In ADHD, a significant reduction of SHANK3 expression was also detected comparing to normal children.

The SHANK family specially SHANK3 gene may play an essential role in the etiology of ASD and ADHD. Findings also may reveal a shared genetic basis in two neurodevelopment disorders related to synaptic pathways.