Pre-addiction phenotype is associated with dopaminergic dysfunction: Evidence from 88.8 million genome-wide association study-based samples

Abstract

The convergence of neurogenetics, epigenetics, and functional neuroimaging presented in this article marks a critical inflection point in our understanding and management of reward deficiency syndrome (RDS) and its behavioral expressions across pain and addiction medicine. The evidence for a hypodopaminergic state, now supported by decades of molecular, clinical, and imaging data, has culminated in the formulation of a scientifically grounded, personalized, and preventative paradigm— anchored by the concept of early genetic testing to provide risk information linked to “prediction” predominantly due to dopaminergic dysfunction. From a translational standpoint, this model offers more than a framework for understanding neurobiological vulnerability; it provides a practical roadmap for early identification of “pre-addiction,” informed opioid prescribing, relapse prevention, and long-term neurorecovery. The coupling of Genetic Addiction Risk Severity (GARS) with dopaminergic modulation—via safe, non-addictive interventions—could redefine standard treatment algorithms not only for substance use disorders but also for a broader spectrum of compulsive and comorbid behaviors. This study by members of the RDS Consortium explores the concept of “pre-addiction” within addiction biology through a comprehensive in silico analysis of 88,788,381 genome-wide association study-based samples from 1,373 studies, identifying 18 significant genes (e.g., APOE with p=1.0E-126) linked to opioids, pain, aging, and apoptosis pathways. It aims to correlate these genes with GARS, which includes 10 specific genes, and highlights the most connected genes, such as MAOA, COMT, APOE, and SLC4A6, through a STRING model. The analysis expanded to 27 unique genes, emphasizing significant interactions with hsa-miR-16-5p and hsa-miR-24-3p, especially SLC6A4. Through pharmacogenomics mining, 1,173 variant annotations were identified for these genes. Enrichment analysis and meta-analysis further validated these findings, illustrating the pivotal role of dopaminergic pathways in connecting addictive behaviors and depressive symptoms. The results support the conceptualization of RDS as the fundamental preaddiction phenotype, with pain, opioid dependence, aging, and apoptosis as critical endophenotypes.

Keywords

Pre-addiction / Genetic addiction risk severity / Dopaminergic pathways / Reward deficiency syndrome / APOE / Opioid dependence / Aging / Apoptosis

Acknowledgments

The authors acknowledge the assistance of Margaret A. Madigan for her professional editing and formatting of the figures and tables in this article.

Funding

This study was funded by the grant (R41 MD012318/MD/ NIMHD NIH HHS/United States; K.B. and M.G.L.).

Conflict of interest

Dr. Kenneth Blum, the senior author, is credited with more than 100 worldwide patents on the GARS test and KB220 and patents pending for gene editing. Dr. Blum has licensed one of his patents (10,894,024) to Victory Nutrition International (VNI). He is a paid scientific advisor to some companies, including Electronic Waveform Labs (Huntington Beach, CA); PEAK LOGIC (Del Mar, CA); Center for Advanced Spine Care of Southern Arizona (Tucson); and Sunder Foundation (Palm Springs, CA). Dr. Kenneth Blum is also the Associate Editor and Kai Uwe Lewandowski and Rajendra D Badgaiyan are the Editorial Board Members of this journal but was not in any way involved in the editorial and peer-review process conducted for this paper, directly or indirectly. Separately, other authors declared that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper.

Author contributions

Conceptualization: Kenneth Blum, Kai Uwe Lewandrowski, Alireza Sharafshah

Formal analysis: Alireza Sharafshah, Kenneth Blum

Investigation: Kenneth Blum, Kai Uwe Lewandrowski, Alireza Sharafshah

Methodology: Alireza Sharafshah, Kenneth Blum

Writing-original draft: Alireza Sharafshah, Kenneth Blum, Kai-Uwe Lewandrowski, Igor Elman, Mark S. Gold, Jean Lud Cadet

Writing-review & editing: All authors

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Availability of data

Data is available from the author Alireza Sharafshah ([e-mail]) upon reasonable request.

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