Study of Genetic Biomarkers of Forensic Interest in Completed Suicide
TRABAJO LIBRE SOMETIDO AL III CONGRESO DE CIENCIAS FORENSES DE HONDURAS DEL 8 AL 10 DE OCTUBRE, TEGUCIGALPA, HONDURAS
Keywords:
Legal medicine, Forensic genetics, Completed suicide, Genetic biomarkers, Gene expression, InflammationAbstract
Introduction:
Suicide is a global public health issue and a challenge in medicolegal investigation, whose understanding requires integration of the psychobiological bases of its etiopathogenesis. The identification of postmortem genetic biomarkers is a promising tool to provide objectivity in forensic investigation and contribute to multidisciplinary suicide prevention.
Methodology:
A cross-sectional descriptive-analytical study was conducted on 66 cases from two Institutes of Legal Medicine in Spain. The study group included 25 deceased by completed suicide, and the control group comprised 41 natural, accidental, and Agitated Delirium deaths. Peripheral blood samples were analyzed postmortem using RT-qPCR to assess gene expression of biomarkers related to inflammation and the endocannabinoid system. Data were analyzed with ANOVA, ANCOVA, and binary logistic regression.
Results:
Significant differences were found in the expression of genes related to immune response and the endocannabinoid system. Post hoc tests showed increased BDNF in suicide and delirium cases compared to natural deaths, and decreased TGFB1. Expression of the fractalkine receptor CX3CR1 suggested an association with acute substance use or psychomotor agitation, with an opposite role in suicide. Logistic regression identified CNR2, CX3CL1, and IL4 as key predictors with high discriminatory capacity.
Discussion and conclusions:
Findings support the involvement of the immune system in completed suicide, especially in individuals with mood disorders, although no exclusive genetic profile was identified. Incorporating multiple genes into predictive models enabled strong discrimination between groups, with sensitivity, specificity, and accuracy close to 100%. These results suggest that biomarkers could serve as a complementary forensic tool, particularly in cases lacking clear evidence of the cause of death.
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References
Klein, A. B., & Fink-Jensen, A. (2017). Brain-derived neurotrophic factor and suicidal behavior. Neuroscience & Biobehavioral Reviews, 83, 302–320. Disponible en: https://doi.org/10.1016/j.neubiorev.2017.10.002
Lu, X., Liu, Y., Sun, X., Li, J., Wang, Y., Jin, W., & Zeng, L. (2019). Decreased expression of interleukin-1β and its receptors in the brains of suicide victims. Psychiatry Research, 273, 41–45.
Miller, A. H., Maletic, V., & Raison, C. L. (2009). Inflammation and its discontents: The role of cytokines in the pathophysiology of major depression. Biological Psychiatry, 65(9), 732–741. Disponible en: https://doi.org/10.1016/j.biopsych.2008.11.029
Turecki, G., & Brent, D. A. (2016). Suicide and suicidal behaviour. The Lancet, 387(10024), 1227–1239. Disponible en: https://doi.org/10.1016/S0140-6736(15)00234-2
Turecki, G., Brent, D. A., Gunnell, D., O’Connor, R. C., Oquendo, M. A., Pirkis, J., & Mann, J. J. (2019). Suicide and suicide risk. Nature Reviews Disease Primers, 5(1), 74. Disponible en: https://doi.org/10.1038/s41572-019-0121-0
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Copyright (c) 2025 Rocio Marino Genicio, Leticia Olga Rubio Lamia, Stella Martín-de-las-Heras, Jimena Arean, Fernando Martín , Juan Suárez
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