Forensic genetics has experienced remarkable advancements over the past decades, evolving from the analysis of a limited number of DNA segments to comprehensive genome-wide investigations. This progression has significantly improved the ability to establish genetic profiles under diverse conditions and scenarios. Beyond individual identification, forensic genetics now enables the inference of physical traits (e.g., eye, hair, and skin color, as well as body composition), biogeographic ancestry, lifestyle habits such as alcohol and tobacco use, and even the transfer of genital microbiomes post-coitus, among other characteristics. Emerging trends point to a future shaped by the integration of cutting-edge technologies, including CRISPR-Cas systems, artificial intelligence, and machine learning, which promise to further revolutionize the field. This review provides a thorough exploration of forensic genetics, tracing its evolution from its foundational methods (past) to its diverse modern applications (present) and offering insights into its potential future directions.

Mitochondrial DNA (mtDNA) analysis is a fundamental tool in forensic genetics, particularly when biological samples exhibit severe degradation or low nuclear DNA content. Its unique biological characteristics, such as a high copy number per cell, strict matrilineal inheritance, and lack of recombination, enable human identification and reconstruction of maternal lineages in complex contexts, including disaster victim identification, historical cases, and missing persons investigations. This narrative review examines contemporary methodological approaches for investigating the human mitogenome. We discuss recent advancements in extraction and enrichment techniques, emphasizing their efficacy in reducing the interference of nuclear mitochondrial DNA sequences (NUMTs) and enhancing the recovery of informative fragments. Moreover, the shift from traditional Sanger sequencing to Massive Parallel Sequencing (MPS) is examined, as MPS has markedly enhanced the sensitivity and capability of contemporary methods to detect low-frequency heteroplasmies. Additionally, the advent of Third-Generation Sequencing (TGS), exemplified by nanopore platforms, is evaluated, which facilitates the reading of full-length native molecules without the biases introduced by PCR amplification. Despite the interpretive challenges posed by heteroplasmy, contamination, and limitations in population databases, ongoing methodological advances in mitochondrial DNA analysis continue to strengthen its reliability and expand its potential in forensic genetics.

Metastases are the leading cause of cancer-related deaths. The spread of neoplasms involves multiple mechanisms, with metastatic tumors exhibiting molecular behaviors distinct from their primary counterparts. The key hallmarks of metastatic lesions include chromosomal instability, copy number alterations (CNAs), and a reduced degree of subclonality. Furthermore, metabolic adaptations such as enhanced glycogen synthesis and storage, as well as increased fatty acid oxidation (FAO), play a critical role in sustaining energy supply in metastases and contributing to chemoresistance. FAO promotes the infiltration of macrophages into the tumor, where they polarize to the M2 phenotype, which is associated with immune suppression and tissue remodeling. Additionally, the tumor microbiome and the action of cytotoxic drugs trigger neutrophil extravasation through inflammatory pathways. Chemoresistant neutrophils in the tumor microenvironment can suppress effector lymphocyte activation and facilitate the formation of neutrophil extracellular traps (NETs), which are linked to drug resistance. This article examines the genomic features of metastatic tumors, along with the metabolic and immunological dynamics within the metastatic tumor microenvironment, and their contribution to drug resistance. It also discusses the molecular mechanisms underlying resistance to chemotherapeutic agents commonly used in the treatment of metastatic cancer.