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Investigation of polymorphic variants of SLC6A4, TPH-1, and TPH-2 genes in cases of completed suicide

  • Duygu Yavuz Kilicaslan1,2,*,
  • Ozge Cumaogullari3
  • Emrah Emiral4
  • Nevriye Tezer5
  • Bedriye Oncu6
  • Hilal Ozdag7
  • Nergis Canturk1
  • N. Lale Satiroglu Tufan4

1Department of Criminalistics, Institute of Forensic Sciences, Ankara University, 06590 Ankara, Turkey

2Department of Autopsy Assistantship, Vocational School of Health Services, Uskudar University, 34664 Istanbul, Turkey

3School of Medicine, Eastern Mediterranean University, 99628 Famagusta, Cyprus

4Department of Forensic Medicine, Ankara University School of Medicine, 06590 Ankara, Turkey

5Morgue Department, Forensic Medicine Institution Ankara Branch, Ministry of Justice, 06300 Ankara, Turkey

6Department of Psyciatry, Ankara University School of Medicine, 06590 Ankara, Turkey

7Ankara University Biotechnology Institute, Ankara University, 06135 Ankara, Turkey

DOI: 10.31083/jomh.2021.116 Vol.18,Issue 3,March 2022 pp.1-9

Submitted: 09 June 2021 Accepted: 25 August 2021

Published: 31 March 2022

*Corresponding Author(s): Duygu Yavuz Kilicaslan E-mail:


Background and objective: Serotonin plays an important role in the pathophysiology of aggressive behavior. Low serotonin levels and altered functions of serotonin receptors affect suicidal behavior. TPH-1, TPH-2 and SLC6A4 genes have important roles in serotonin production and degradation pathways. In this study, polymorphic variants of the TPH-1, TPH-2 and SLC6A4 genes, rs1800532, rs7305115, rs6355 and rs1386494, were investigated in 100 completed suicides and 100 healthy individuals.

Materials and methods: After DNA isolation, a new polymerase chain reaction technology KASP TM (Competitive allele-specific polymerase chain reaction method), was used in the genotyping of the selected gene variants.

Results: No statistically significant difference was found for the genotype and individual allele frequencies of the polymorphic variants between suicide and control groups, as well as between men and women in suicide cases. However, we observed non-significant tendencies of increased minor alleles in suicidal men for all TPH SNPs.

Conclusions: More molecular genetic research studies are needed to understand the pathophysiology of suicide and to reveal its relationship with gender.


Suicide; Polymorphism; KASP; TPH-1; TPH-2; SLC6A4

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Duygu Yavuz Kilicaslan,Ozge Cumaogullari,Emrah Emiral,Nevriye Tezer,Bedriye Oncu,Hilal Ozdag,Nergis Canturk,N. Lale Satiroglu Tufan. Investigation of polymorphic variants of SLC6A4, TPH-1, and TPH-2 genes in cases of completed suicide. Journal of Men's Health. 2022. 18(3);1-9.


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