ADHD Defects and Differences

Attention deficit hyperactivity disorder patients exhibit genetic defects

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) As ADHD becomes a commonplace acronym in our society, how many people are aware that the disorder affects patients differently? 

Pediatricians discovered alterations in genes apparent in a tenth of attention-deficit hyperactivity disorder children. Although the doctors suspected the genetic mutations, the exciting finding sheds light on the pathology of a common disorder.

"Ask a pediatrician about emerging treatments specific to your symptoms."

A study published in the journal Nature Genetics analyzed the human genome of 1,000 ADHD children from The Children’s Hospital in Philadelphia and 4,100 children without the disorder. Looking for copy number variants or deletions/duplications in the DNA sequence, researchers evaluated results in independent cohorts including 2,500 cases of ADHD and 9,200 controls.

Lead researcher on the study and Director of Applied Genomics at the Children's Hospital, Hakon Hakonarson, MD, PhD explains, “at least 10 percent of the ADHD patients in our sample have these particular genetic variants. The genes involved affect neurotransmitter systems in the brain that have been implicated in ADHD, and we now have a genetic explanation for this link that applies to a subset of children with the disorder.”

Findings depicted four genes involved that held a higher number of variants within ADHD patients, specifically within the glutamate receptor gene family. An important neurotransmitter, glutamate transmits signals from neuron to neuron in the brain.

Digging into the intricacies of the findings, Dr. Hakonarson explains that “members of the GMR gene family, along with genes they interact with, affect nerve transmission, the formation of neurons and interconnections in the brain.” Dr. Hakonarson also adds that their discovery “reinforces previous evidence that the GMR pathway is important in ADHD.”

The findings were consistent with past animal studies, brain scans and pharmacology illustrating the aforementioned pathways as important ADHD attributes. Highlighting potential pathology in ten percent of ADHD cases is a huge finding in a disorder affecting over five million Americans.

dailyRx contributing expert LuAnn Pierce, LCSW, expressed, "The findings of this study are both exciting and promising for children and adults with ADHD. Research available from small samples of twin and family studies have estimated the genetic link to be as high as 80% that a parent with ADHD will have one or more children with ADHD, and that most children with ADHD will have a blood relative with ADHD."

Millions suffer from some subtype of ADHD, with treatments ranging in severity. Pathology suggestions range from genetics to diet, and an appropriate therapy can be tailored to individual factors and symptoms. This research allows doctors to focus on developing treatment methods for the ten percent of ADHD patients with genetic mutations.

Pierce added, "Research findings like this should lend more credibility to the disorder, which to date remains highly suspect by many who don't understand the diagnosis, and believe the symptoms to be bad behavior instead of a legitimate invisible neurological disorder."

Researchers from the study anticipate their findings to set the stage for future enlightenment in regards to the pathology of attention-deficit hyperactivity disorder. Furthermore, doctors expect their research to elicit new treatments for the ten percent with genetic variations.

Reviewed by: 
Review Date: 
December 5, 2011
Last Updated:
October 2, 2012