THE ESSENTIAL
- A mutation in the STAT1 gene has been identified as being linked to ADHD.
- This mutation disrupts the functioning of dopaminergic neurons and the person’s behavior.
- This discovery could, ultimately, allow the development of new treatments for ADHD.
Attention deficit disorder with or without hyperactivity (ADHD) affects 5.9% of those under 18 and 2.8% of adults according to the National Institute of Health and Medical Research (Inserm). This is characterized by high levels of inattention, and/or agitation and impulsivity. For now, scientists know that this disorder is due to an accumulation of genetic and environmental factors, but its origin still remains mysterious.
Dare researchers of Duke Healthin the United States, in partnership with a team from theColumbia Universityhave just made a major breakthrough. They discovered a gene, or rather one of its mutations, which could explain the development of neurobehavioral disorders, including ADHD. They presented their work in the journal Brain, Behavior, and Immunity.
The STAT1 gene linked to the response of the immune system and neurodisordersdevelopment
The gene in question is STAT1. It plays an important role in the immune system’s response to infections. However, STAT1 has also been implicated in various neurodevelopmental disorders such as autism in previous studies.
“Many of the signaling pathways that have been discovered in the immune system also play important roles in the brain, indicates Anthony Filiano, main author, in a press release. There is very strong communication between the two systems [nerveux et immunitaires]. This is intriguing because the immune system can very easily be targeted therapeutically.”
In their experiments, the scientists studied mice that had a mutation in the STAT1 gene. In these rodents, they overactivated the immune pathway in different types of brain cells, including dopamine neurons, which are involved in motivation, reward circuitry and motor control.
Targeting the STAT1 gene to treat ADHD?
Thus, the researchers observed that the mutation of the STAT1 gene led to overactivation of the STAT1 gene and then of the immune system. This overactivation also impacted the functioning of neurons and disrupted the behavior of the mice.
“The [sur-activation de] STAT1 in neurons, which begins during embryonic development, leads to hyperactive behavior, decreased neuron numbers, and reduced neuronal activity in an area of the brain involved in learning, memory, reward, and motivation , explains Anthony Filiano. These results suggest that the [sur-activation de] STAT1 in dopamine neurons plays a role in regulating behavior and that [cette] disruption may contribute to neurodevelopmental disorders”.
In the future, the team plans to continue their research to perhaps ultimately target the STAT1 gene as part of a new therapy for ADHD. “We need to understand its function and target it more specifically before moving forward”, concludes Anthony Filiano.
