What causes ADHD? New Israeli study may have found out

ADHD is one of the most common mental disorders that usually first show up during childhood. This disorder in particular is characterized by hyperactivity and difficulty focusing.

 Brain of a child with ADHD with overall reduced volume and a proportional reduction in the left-sided prefrontal cortex. (photo credit: Wikimedia Commons)
Brain of a child with ADHD with overall reduced volume and a proportional reduction in the left-sided prefrontal cortex.
(photo credit: Wikimedia Commons)

Israeli scientists have cracked code to better understand the genetic causes of attention deficit hyperactivity disorder (ADHD).

This new study was carried out by researchers from the Ben-Gurion University of the Negev and Soroka-University Medical Center and was published in the peer-reviewed academic journal Nature Communications.

ADHD is one of the most common mental disorders that usually first show up during childhood. This disorder in particular is characterized by hyperactivity and difficulty focusing.

But what causes it?

It is obvious that there is a genetic predisposition to it. But how exactly does it work? Which genes are affected?

Ben-Gurion University of the Negev (BGU). (credit: AMERICANS FOR BEN-GURION UNIVERSITY)
Ben-Gurion University of the Negev (BGU). (credit: AMERICANS FOR BEN-GURION UNIVERSITY)

According to the new study, that gene may just be CDH2, should that gene mutate.

CDH2 is a gene that encodes N-cadherin, which is responsible for helping in brain synapse activity and formation. A mutation in CDH2, however, alters this activity. This, in turn, impacts molecular pathways and dopamine levels in two specific brain structures: the ventral midbrain and the prefrontal cortex, both of which are involved in ADHD.

This was tested by using CRISPR to insert this type of mutation in homologous mouse genes, which caused hereditary hyperactivity.

The implications of this finding could help pave the way for further understanding how ADHD works, and how it can be treated and managed.

"In addition to the scientific importance of finding a clear delineation of a novel genetic basis and molecular pathways for ADHD, both the mutant human cells and the mouse strain carrying the human mutation can serve as an effective model system for the discovery of novel medications for ADHD," one of the authors, Prof. Ohad Birk, said in a statement.

Further studies have been initiated by the Birk team at BGU’s National Institute for Biotechnology in the Negev (NIBN).