Another Piece of the Puzzle? New Research Zeroes In On the Specific Genetic Components of ADHD
Researchers have long known that the gene known as ADGRL3 is linked to ADHD, but they’ve not understood exactly how. Now, new research has identified a variation on the gene that may clarify the cause-and-effect pathway to ADHD.
January 10, 2017
ADHD is highly genetic, and one gene in particular has long been implicated it its development. That gene, ADGRL3, has common variations that have consistently been linked to ADHD in children and adults; some variations can even help researchers predict the severity of a patient’s ADHD symptoms. Now, a new study goes even further, finding a specific malfunction on the gene that is highly associated with ADHD and related disorders — clearing the way for specialized medications and greater understanding of the neural pathways behind ADHD.
The study, published in the journal Biological Psychiatry on December 15, 2016, analyzed the ADGRL3 gene in 838 people, 372 of whom had ADHD. Researchers identified one specific section of the gene — known as the ECR47 transcriptional enhancer — that worked differently in the brains of those with ADHD. They found that a malfunction in ECR47 caused the ADGRL3 gene to be expressed less in the thalamus — a key region in the brain involved in motor skills and alertness — and was linked to decreased sensory processing abilities, as well as to classic ADHD symptoms like impulsivity and inattention.
The results provide just a small piece of the puzzle of the genetic components that control ADHD, the researchers said, but the progress is promising — particularly when it comes to the development of new medications.
“In this new era of genomics and precision medicine, the key to success lies in dissecting genetic contributions and involving some level of patient stratification,” said Ariel Martinez, M.S., a lead author of the study. This means that medications could be created that specifically target the ADGRL3 gene — or even the ECR47 mutation — to benefit patients for whom traditional stimulants don’t work.
“Martinez and colleagues help us to understand how variation in the ADGRL3 gene might contribute to thalamic dysfunction in ADHD,” said John Krystal, editor of Biological Psychiatry. “The brain is extraordinarily complex. Yet we are starting to pull on the threads of that complex biology that reveal mechanisms through which disorders like ADHD might develop.”