Epigenetic Markers in Criminal Investigation: A Narrative Synthesis of Recent Evidence

Forensic epigenetics has become a rapidly expanding frontier in molecular forensics, offering analytical capabilities that surpass those of traditional genetic markers.Advances in high-resolution methylome profiling, small-RNA analysis, and multi-omics approaches now support increasingly precise inferences about biological age, tissue origin, lifestyle exposures, and, in some cases, individual differentiation.Despite this progress, the field remains transitional, and its adoption in routine forensic practice requires methodological standardization, analytical validation, and legal evaluation.This narrative review synthesizes findings from studies indexed in PubMed, Scopus, and Web of Science, of which 61 met the eligibility criteria after duplicate removal and fulltext assessment.These studies were categorized according to epigenetic mechanism, forensic application, methodological design, technological innovation, and legal or operational considerations.DNA methylation emerged as the most extensively explored mechanism, particularly for age estimation, body-fluid identification, and differentiation of monozygotic twins.MicroRNAs constituted the second most frequently examined biomarker class, demonstrating high stability in degraded samples and strong tissue specificity, with applications in postmortem interval estimation and cause-of-death assessment.Histone modifications were investigated less often due to technical challenges related to protein instability and environmental degradation.Across mechanisms, limited standardization in sampling, extraction, sequencing, and computational modeling remains a major barrier to reproducibility.Nevertheless, recent advances-including third-generation sequencing, refined methylation assays, and machine-learning frameworks integrating complex epigenomic and transcriptomic signals-suggest substantial future potential.