Newly mapped genes may hold the keys to ADHD

MONDAY, Nov. 26, 2018 (HealthDay News) – New study suggests millions of Americans with hyperactivity, hyperactivity, or hyperactivity disorder (ADHD) may be at risk of genetic vulnerability to the disease.

The researchers analyzed data from more than 55,000 people and identified 12 gene regions related to ADHD. These regions probably affect the central nervous system, according to the authors of the study. This discovery could help scientists develop new treatments for ADHD, which affects more than 9% of American children.

"We all carry genetic variants of ADHD risk," said researcher Anders Borglum, professor of biomedicine at Denmark's Aarhus University. "The more we have, the more we risk developing ADHD."

These same genetic areas share a link with 200 other diseases and traits, he said. The researchers also found that 44 variants of genes involved in ADHD were linked to depression, anorexia and insomnia.

"We now understand better why some people develop ADHD and begin to understand the underlying biology, paving the way for new and improved treatment for ADHD," Borglum added.

The genetic areas that his team has discovered show that it's mainly a brain disorder, Borglum said.

The researchers also discovered that ADHD-related genes play a role in the interaction of brain cells and also have an impact on speech development, dopamine learning and regulation (a chemical messenger that transmits signals between brain cells).

Nevertheless, the vast majority of ADHD genes have not yet been discovered and will require further study, Borglum said.

The study's author, Stephen Faraone, said the team "has discovered 12 of the many genes – probably thousands of genes related to ADHD – we do not know." Faraone is Professor of Psychiatry and Behavioral Sciences at SUNY Upstate Medical University in Syracuse, New York.

Researchers do not expect to discover one, two or even ten genes that each have a significant effect on ADHD and can be used to diagnose the disorder or quickly develop treatment, he said. Most likely, a combination of genes and environmental factors triggers ADHD, according to the authors of the study.

Environmental factors can include premature birth and underweight or developmental problems, such as Fetal Alcohol Syndrome, said Faraone.

Interestingly, he added, even though the drugs work in the treatment of ADHD, they do not target the genes that, according to the investigators, are linked to the disease. According to Faraone, none of the genes affected by the drugs were found during the analysis of genes related to ADHD.

The report was published online November 26 in the journal Nature Genetics.

Ronald Brown, Dean of the Faculty of Health Sciences at the University of Nevada Las Vegas, said: "This is a promising survey because it provides further evidence that the ADHD is probably a hereditary disorder. " Brown did not participate in the study, but was aware of the results.

It has been clear for years that ADHD is practiced in families, he said. These findings are also important because they suggest that some effective therapies for one family member will likely be effective for other family members diagnosed with ADHD, he added.

This study is also important because it shows that several psychological disorders are probably related to these genes, although no cause-and-effect relationship has been demonstrated in the study. This information could help families with prevention efforts and early intervention, Brown said.

More information

Visit the US National Institute of Mental Health to learn more about ADHD.