Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that can affect up to 7% of school-age children and continue to be present in 4.5% of adults, according to experts from the Association. Spanish Department of Pediatrics (AEP), which warn that this condition can have important consequences, both on the child’s academic performance, as well as on their social relationships and family environment, so early detection and adequate treatment are essential.
Research carried out at the University of Surrey (United Kingdom) has identified several new genes associated with externalizing disorders such as attention deficit hyperactivity disorder (ADHD), revealing a significant connection between this type of alterations and our immune system, which could lead to the development of new therapies that reduce its impact. The study also confirms the role of the ADGRL3 gene in conditions such as ADHD, providing greater understanding of its functioning.
“The high degree of heritability of externalizing disorders, such as ADHD, has intensified the search to identify genes that cause such behaviors, which we hope will help develop specific treatment options to alleviate their symptoms,” said Dr. Matt Parker. , Senior Lecturer in Neuroscience and Sleep Sciences at the University of Surrey. “This is important as it will not only help people better manage their condition, but can also help improve their chances in life – for example, it is estimated that 26% of prisoners have ADHD.”
A gene that interferes with attention and increases impulsivity
The experiments were carried out in zebrafish, as they share 70% of the genes with humans and 84% of these genes are known to be associated with human disease. Using a behavioral task that tracks the fish’s ability and willingness to “wait,” the researchers found that zebrafish with the ADGRL3 gene edited had higher levels of inattention and showed greater impulsivity compared to wild-type fish. whose gene worked normally.
“Identifying these genes is potentially the first step in developing new targeted medications to help ADHD patients better manage their symptoms.”
These features were more prominent in male zebrafish with the modified ADGRL3 gene, compared to their female counterparts. Administration of atomoxetine, a medication used in the treatment of ADHD, completely reversed impulsivity. Next, the team analyzed genetic differences in zebrafish brains with and without the ADGRL3 gene. They did this because ADGRL3 is an important gene in the development of the nervous system, so its dysfunction will have knock-on effects on other areas of the body.
Interestingly, they found evidence supporting the idea that the immune system is crucial in the development of ADHD and similar disorders. They identified several genes and groups of genes that were independent of drug treatment and that may contribute to the behaviors that characterize individuals with externalizing disorders. The findings have been published in Translational Psychiatry.
“The discovery of these genes is very exciting, as it shows that there are more genes that contribute to externalizing disorders than we previously thought. Identifying these genes is potentially the first step in developing new targeted medications to help patients better manage their symptoms,” concludes Dr. Parker.
