Mitochondrial DNA (mtDNA) presents several characteristics useful for forensic studies, especially related to the lack of recombination, to a high copy number, and to matrilineal inheritance. mtDNA typing based on sequences of the control region or full genomic sequences analysis is used to analyze a variety of forensic samples such as old bones, teeth and hair, as well as other biological samples where the DNA content is low. Evaluation and reporting of the results requires careful consideration of biological issues as well as other issues such as nomenclature and reference population databases. In this work we review mitochondrial DNA profiling methods used for human identification and present their use in the main cases of humanidentification focusing on the most relevant issues for forensics.

Tramadol concentrations and analgesic effect are dependent on the CYP2D6 enzymatic activity. It is well known that some genetic polymorphisms are responsible for the variability in the expression of this enzyme and in the individual drug response. The detection of allelic variants described as non-functional can be useful to explain some circumstances of death in the study of post-mortem cases with tramadol. A Sanger sequencing methodology was developed for the detection of genetic variants that cause absent or reduced CYP2D6 activity, such as *3, *4, *6, *8, *10 and *12 alleles. This methodology, as well as the GC/MS method for the detection and quantification of tramadol and its main metabolites in blood samples was fully validated in accordance with international guidelines. Both methodologies were successfully applied to 100 post-mortem blood samples and the relation between toxicological and genetic results evaluated. Tramadol metabolism, expressed as its metabolites concentration ratio (N-desmethyltramadol/O-desmethyltramadol), has been shown to be correlated with the poor-metabolizer phenotype based on genetic characterization. It was also demonstrated the importance of enzyme inhibitors identification in toxicological analysis. According to our knowledge, this is the first study where a CYP2D6 sequencing methodology is validated and applied to post-mortem samples, in Portugal. The developed methodology allows the data collection of post-mortem cases, which is of primordial importance to enhance the application of these genetic tools to forensic toxicology and pathology.

Non-tuberculous mycobacteria (NTM) are responsible for an increase in mycobacterial disease in many developed countries. However the epidemiology, especially in patients without HIV infection, remains difficult to determine. We studied a convenience sample of 5497 HIV-negative patients receiving care at our pneumology centres. Among 510 patients with mycobacterial isolates, NTM were demonstrated in 58, all showing signs of lung disease. The mycobacteria isolated were M. intracellulare (n = 9, 15.5%), M. fortuitum (n = 8, 13.8%), M. gordonae (n = 7, 12.1%), M. kansasii (n = 6, 10.3%), M. chelonae (n = 5, 8.6%), M. avium (n = 4, 6.9%), M. abscessus (n = 3, 5.2%), M. peregrinum (n = 3, 5.2%), M. triplex (n = 3, 5.2%), M. spp. (n = 3, 5.2%), M. szulgai (n = 3, 5.2%), M. mucogenicum (n = 2, 3.4%), M. lentiflavum (n = 1, 1.7%) and M. simiae (n = 1, 1.7%). The present high percentage of NTM strains among mycobacterial isolates (approximately 11%), suggests the emergence of NTM infections as a public health problem. Larger, multicentre and multiregional studies or mandatory reporting will be required to better understand the changing epidemiology of NTM in patients with lung disease.

Background/Objectives: The Y chromosome is a crucial tool in forensic genetics due to its unique characteristics, such as its haploid inheritance and lack of recombination. Y-STRs (short tandem repeats on the Y chromosome) are widely used for identifying male genetic profiles in DNA mixtures, especially in sexual assault cases where high levels of female DNA hinder autosomal analysis. This study evaluates the applicability of Y-STRs in forensic investigations, addressing their limitations and the impact of advanced technologies, such as rapidly mutating Y-STRs (RM Y-STRs). Methods: A comprehensive literature review was conducted to analyze existing knowledge on the application of Y-STRs in sexual crimes. The study also examines the role of population databases, such as YHRD, in estimating haplotype frequencies and enhancing forensic reliability. Results: Y-STR analysis proves essential for male DNA identification in complex mixtures, with RM Y-STRs enhancing discriminatory power. However, limitations persist, particularly in cases involving closely related male lineages. The population database coverage remains insufficient in regions like Cape Verde, affecting forensic reliability. Case studies demonstrate Y-STR effectiveness in solving cold cases and sexual crimes, reinforcing the need for expanded databases and methodological advancements. Conclusions: Y-STRs play a fundamental role in forensic genetics, particularly in sexual assault investigations. Their integration with advanced sequencing technologies and expanded databases is critical for improving forensic accuracy. Ethical considerations regarding genetic data privacy and potential discrimination must be addressed through clear regulations and forensic best practices.