Evidence mapPaperPMID 41968640Full record

SynthesisNeuropsychopharmacology reports2026

Japanese Cohort Study Identifies an Association Between the Serotonin Transporter-Linked Polymorphic Region and Suicide Death.

Shohei Okada, Toshiyuki Shirai, Masao Miyachi, Gentaro Yamasaki, Kiriko Minami, Ryo Tsukamoto, Kentaro Mouri, Takaki Tanifuji, Ryuichi Katada, Satoshi Okazaki and 2 more

Abstract readMeta-Analysis
In one paragraph

Synthesis in Neuropsychopharmacology reports, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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4 · The record

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5 · Who and what money

Authors and funding

12 authors.

Shohei OkadaDepartment of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan.
Toshiyuki ShiraiDepartment of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan.ORCID https://orcid.org/0009-0009-2058-1678
Masao MiyachiDepartment of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan.
Gentaro YamasakiDivision of Legal Medicine, Department of Community Medicine and Social Health Science, Kobe University Graduate School of Medicine, Kobe, Japan.
Kiriko MinamiDepartment of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan.
Ryo TsukamotoDepartment of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan.
Kentaro MouriDepartment of Rehabilitation Science, Kobe University Graduate School of Health Sciences, Kobe, Japan.
Takaki TanifujiDepartment of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan.
Ryuichi KatadaDivision of Legal Medicine, Department of Community Medicine and Social Health Science, Kobe University Graduate School of Medicine, Kobe, Japan.
Satoshi OkazakiKobe University Inclusive Campus & Healthcare Center, Kobe, Japan.ORCID https://orcid.org/0000-0001-5953-5526
Ikuo OtsukaDepartment of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan.ORCID https://orcid.org/0000-0002-2831-9158
Akitoyo HishimotoDepartment of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan.

Funding

Japan Agency for Medical Research and Development 23dk0307111Japan Society for the Promotion of Science JP21H02852Japan Society for the Promotion of Science JP21K07520Japan Society for the Promotion of Science JP24K0238Japan Society for the Promotion of Science JP24K10710Japan Society for the Promotion of Science JP24K10732Japan Society for the Promotion of Science JP25K19058Moonshot Research and Development Program JPMJMS239FSENSHIN Medical Research FoundationSmoking Research Foundation
6 · The paper itself

Abstract

introductionMore than 720 000 individuals die by suicide annually worldwide, making it a major public health concern and a leading cause of death among young people, particularly in Asian populations. Dysregulation of the 5-hydroxytryptamine system has been implicated in suicide risk. The SLC6A4 gene encodes the serotonin transporter, which regulates synaptic 5-hydroxytryptamine levels. Its promoter region contains a 44-base-pair insertion/deletion polymorphism, known as the serotonin-transporter-linked polymorphic region (5-HTTLPR). We examined the association between the 5-HTTLPR polymorphism and suicide death in a Japanese cohort, representing the largest sample from an Asian population to date.

methodsWe included 448 suicide decedents and 361 controls. Genomic DNA was extracted from peripheral blood, and 5-HTTLPR genotypes were determined using PCR. We evaluated genotype- and allele-level associations with suicide. Additionally, we conducted a meta-analysis incorporating previous studies.

resultsThe distributions of 5-HTTLPR genotypes and alleles differed significantly between suicide decedents and controls (S allele: OR = 1.62, 95% CI = 1.26-2.09, p < 0.001). The associations remained significant in subgroup analyses by sex, age group, and violent methods. Age- and sex-matched analyses yielded consistent results. However, the random-effects meta-analysis did not demonstrate a significant association.

conclusionOur findings indicate a potential association between 5-HTTLPR polymorphisms and suicide death in a Japanese population. Although further research in larger and diverse samples is warranted, these results may contribute to a better understanding of the biological underpinnings of suicide risk.

Indexed as

Polymorphism, GeneticSerotonin Plasma Membrane Transport ProteinsSuicideAdultAgedCohort StudiesEast Asian PeopleFemaleGenetic Association StudiesGenotypeHumansJapanMaleMiddle AgedSerotonin Plasma Membrane Transport ProteinsSLC6A4 protein, human5‐HTTLPRmeta‐analysissuicide

Identifiers

PMID41968640
PMCPMC13071177

What Socratic holds

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.