Genetic Associations of Serotonin Receptor Variants and Suicidal Behavior

The serotonergic system, and in particular the serotonin receptor 2A (5-HT2AR) encoded by HTR2A, has been implicated in modulation of mood, impulse control and stress resilience. Common and rare variants in HTR2A, as well as in related receptors such as HTR1A, may influence receptor expression, signalling efficacy and downstream gene networks. Investigations have ranged from candidate-gene case–control studies to genome-wide scans, epigenetic profiling and in vitro functional assays. Evidence suggests that polymorphisms in promoter regions and untranslated exons can alter transcriptional activity, while coding variants may modify ligand binding or receptor trafficking. DNA methylation of regulatory CpG sites further integrates environmental exposures, such as childhood adversity or maternal metabolic status, into long-term risk trajectories. Although individual variants often confer modest effect sizes and findings vary across populations, convergence on disrupted 5-HT2AR function underscores its potential as a biomarker and therapeutic target. Translational models, including human-induced pluripotent stem cell-derived neurons, now enable direct interrogation of variant-specific phenotypes. Continued integration of epidemiological, molecular and functional approaches promises to clarify the genetic architecture of suicidal behaviour, inform prevention strategies and guide precision interventions in diverse clinical settings.

Research from Nature Portfolio

Advanced in vitro models have begun to recapitulate the functional impact of HTR2A variants. In one study, human-induced pluripotent stem cells were differentiated into neurons expressing 5-HT2AR under control of a promoter-specific reporter lentivirus. Electrophysiological recordings revealed that maturation-dependent expression of HTR2A yielded characteristic action potentials and inward currents upon application of a selective 5-HT2AR agonist. This system faithfully mirrored native receptor dynamics and offers a platform to dissect the pathogenic consequences of patient-derived HTR2A mutations, bridging genetic findings with cellular physiology.

Genetic Associations of Serotonin Receptor Variants and Suicidal Behavior publication trend

The graph below shows the total number of articles in genetic associations of serotonin receptor variants and suicidal behavior across all publications each year (not limited to Nature Index journals).

Technical terms

5-HT2AR: Serotonin receptor subtype 2A, a G-protein-coupled receptor implicated in mood and cognition.

Single nucleotide polymorphism (SNP): A single base-pair variation in the genome that may influence gene function or regulation.

Human-induced pluripotent stem cell (hiPSC): A reprogrammed human cell capable of differentiating into multiple lineages, used to model disease in vitro.

Missense mutation: A DNA change that results in substitution of one amino acid for another in the encoded protein.

DNA methylation: An epigenetic modification involving addition of methyl groups to cytosine residues, often altering gene expression.

Case–control study: An observational design comparing genetic variants between individuals with a trait (cases) and without (controls).

References

1. Genomic structure and expression of the human serotonin 2A receptor gene (HTR2A) locus: identification of novel HTR2A and antisense (HTR2A-AS1) exons. BMC Genomic Data (2016).
2. Childhood Adversity Moderates the Effects of HTR2A Epigenetic Regulatory Polymorphisms on Rumination. Frontiers in Psychiatry (2019).
3. Maternal Metabolic State and Fetal Sex and Genotype Modulate Methylation of the Serotonin Receptor Type 2A Gene (HTR2A) in the Human Placenta. Biomedicines (2022).
4. In vitro monitoring of HTR2A-positive neurons derived from human-induced pluripotent stem cells. Scientific Reports (2021).
5. Association of the 5HTR2A gene with suicidal behavior: CASE-control study and updated meta-analysis. BMC Psychiatry (2013).
6. Genetic Analysis of Suicide: A Sample Study in Tuscany (Central Italy). Forensic Sciences Research (2022).