en Biological Sciences Biological Sciences Review Article Review Article <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-style:italic"><b><span style="font-size:9.0pt"><span style="font-style:normal">Background: </span></span></b><span style="font-size:9.0pt"><span style="font-style:normal">Suicidal behavior is a complex and multifactorial phenomenon rooted in both psychological and biological mechanisms. In recent years, there has been an increasing focus on epigenetic factors, which modulate the influence of environmental factors on the expression of genes associated with emotional and cognitive regulation. </span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-style:italic"><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp;&nbsp; <b>Review of the literature:</b> This review aims to provide a comprehensive analysis of contemporary scientific data concerning the epigenetic mechanisms implicated in the pathogenesis of suicidal behavior. It synthesizes and systematizes findings published between 2013 and 2024, emphasizing DNA methylation, histone modifications, and non-coding RNA (microRNA and long non-coding RNA) regulation as key molecular pathways involved in impaired neuroplasticity, dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, and dysfunction of neurotransmitter systems. </span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-style:italic"><b><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp;&nbsp; Discussion:</span></span></b><span style="font-size:9.0pt"><span style="font-style:normal"> The review highlights the role of epigenetic regulation in genes associated with the serotonergic system (SLC6A4), neuroendocrine stress response (FKBP5), and HPA axis regulation (SKA2, NR3C1, NR3C2), as well as relatively novel candidate genes such as CACNA1C, SIRT1, and IMPA2. It underscores how stress-induced and trauma-related epigenetic modifications contribute to suicidal vulnerability and may underlie the biological heterogeneity observed among individuals exhibiting suicidal behavior. The potential reversibility of epigenetic changes positions them as attractive targets for therapeutic and preventive strategies. &nbsp;</span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-style:italic"><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp;&nbsp; <b>Conclusion:</b> Epigenetic changes induced by environmental stressors, traumatic experiences, or mental disorders possess diagnostic and prognostic potential. The integration of epigenetic biomarkers into clinical research may enhance the early identification of individuals at risk, support the development of personalized interventions, and contribute to new approaches in suicide prevention. Overall, epigenetics offers a promising framework for bridging molecular biology with psychiatry and deepening our understanding of the biological mechanisms underlying suicidality. </span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-style:italic"><span style="font-size:9.0pt"><span style="font-style:normal"></span></span></span></span></span></span></span></span><br> &nbsp; Suicidal behavior, Epigenetics, Epigenetic mechanisms, DNA methylation, Histone modification, microRNA, Biomarkers, Neurotransmitter regulation, Global methylation, ncRNA 160 181 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-9670-1&slc_lang=en&sid=1 Aruzhan Tussupova aruzhan_1803@mail.ru 200319475328460096792 200319475328460096792 No Department of General Biology and Genomics, L.N. Gumilyov Eurasian National University, Zhangeldina St. 26, 010000 Astana, Kazakhstan Roza Tatayeva rktastana23@mail.ru 200319475328460096793 200319475328460096793 Yes Department of General Biology and Genomics, L.N. Gumilyov Eurasian National University, Petrova St. 5/3, 010000 Astana, Kazakhstan Sholpan Koygeldinova kshs@list.ru 200319475328460096794 200319475328460096794 No Department of Internal Medicine, Karaganda Medical University, Gogolya St. 40, 100000 Karaganda, Kazakhstan Zhannat Bazarbayeva bazarbayeva@inbox.ru 200319475328460096795 0009-0000-6851-7960 No Department of General Biology and Genomics, L.N. Gumilyov Eurasian National University, Satpayeva St. 2, 010000 Astana, Kazakhstan Zhibek Sembaeva zhibek_sembaeva@yandex.ru 200319475328460096796 0009-0006-8374-8322 No Department of General Biology and Genomics, L.N. Gumilyov Eurasian National University, Imanova St. 2, 010000 Astana, Kazakhstan Aiman Mussina mussina.a@amu.kz 200319475328460096797 200319475328460096797 No NJSC “Astana Medical University”, Bogenbay St. 12, 010000 Astana, Kazakhstan