Are Serotonin Transporter Genes Implicated in ADHD?

PostedAugust 18, 2025

UpdatedSeptember 3, 2025

ByMy Patient Advice

Author: Lucia Alvarez, MSc | Reviewed by: Dr. Rebecca Fernandez, MBBS

Yes, the serotonin gene, specifically the one coding for the serotonin transporter (SERT), has been increasingly studied for its role in ADHD. While dopamine and norepinephrine systems are central to ADHD, serotonin contributes to mood regulation, impulse control, and emotional balance. Research suggests that variations in the serotonin gene ADHD pathway may influence symptom severity, emotional dysregulation, and the presence of comorbid conditions like anxiety or depression.

This expands our understanding of ADHD as not just a disorder of attention, but one that involves broader neurochemical imbalances.

The Role of Serotonin in ADHD Complexity

Here’s how serotonin-related genes may shape the ADHD experience.

SERT Gene

The SERT gene (also known as SLC6A4) controls how serotonin is reabsorbed in the brain. Certain variants can reduce transporter efficiency, potentially leading to irritability, anxiety, or mood swings, symptoms that can overlap or intensify typical ADHD behaviours.

ADHD Comorbidity

Individuals with ADHD and SERT gene variations are more likely to experience ADHD comorbidities such as depression or generalised anxiety. These overlapping traits may require combined treatment approaches, including mood stabilisers, therapy, or mindfulness-based interventions.

Exploring the serotonin gene ADHD connection offers a more nuanced approach to diagnosis and care.

Visit providers like ADHD Certify for comprehensive evaluations that account for both attentional and emotional profiles.

For a deeper dive into the science, diagnosis, and full treatment landscape, read our complete guide to Genetic Factors in ADHD.

Lucia Alvarez, MSc

Author

Lucia Alvarez is a clinical psychologist with a Master’s in Clinical Psychology and extensive experience providing evidence-based therapy and psychological assessment to children, adolescents, and adults. Skilled in CBT, DBT, and other therapeutic interventions, she has worked in hospital, community, and residential care settings. Her expertise includes grief counseling, anxiety management, and resilience-building, with a strong focus on creating safe, supportive environments to improve mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the author's privacy.

Dr. Rebecca Fernandez, MBBS

Reviewer

Dr. Rebecca Fernandez is a UK-trained physician with an MBBS and experience in general surgery, cardiology, internal medicine, gynecology, intensive care, and emergency medicine. She has managed critically ill patients, stabilised acute trauma cases, and provided comprehensive inpatient and outpatient care. In psychiatry, Dr. Fernandez has worked with psychotic, mood, anxiety, and substance use disorders, applying evidence-based approaches such as CBT, ACT, and mindfulness-based therapies. Her skills span patient assessment, treatment planning, and the integration of digital health solutions to support mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the reviewer's privacy.