This presentation will describe the main aspects of population genetics that support forensic practice. Population genetics provides the statistical basis for a robust interpretation of genetic evidence in forensic genetics. Central to the forensic field is the characterization of allelic/haplotypic frequency distributions and population structure, which supports the calculation of matching probabilities and likelihood ratios for both recombining and non-recombining markers.

Advances in the study of genetic variation and its population distribution patterns have strengthened applications in human identification, complex kinship analysis, and inference of maternal and paternal lineages. Understanding population diversity has also contributed to improved modeling of mutation processes, particularly for microsatellites, refining statistical assessments in kinship testing. Knowledge of population history has also proven relevant in the interpretation of forensic cases involving specific populations.

The reconstruction of demographic events that shape the distribution of alleles/haplotypes in populations has played an important role in understanding population substructure, particularly for regions shaped by recent and complex demographic histories. Advances in population genetics applied to forensic science have increased the accuracy of statistical inferences related to the strength of evidence, enabling methodological innovations in kinship inference, probabilistic interpretation of genetic mixtures, and assessment of allelic/haplotype frequency uncertainty, reinforcing its essential role in the resolution of forensic cases.

Despite this, population genetics applied to forensic science still faces several challenges. There is still a lack of representativeness of population data for some countries, hindering robust statistical inferences. This heterogeneity of representativeness worldwide has been further aggravated by rapid technological advances, including an increasingly wide range of markers, which in complex cases involving samples with low amounts of genetic material, mixtures, or closely related individuals, further overburden existing statistical models. At the same time, ethical and legal concerns related to privacy, proportionality, and communication of probabilistic results have been raised, highlighting the importance of clear and careful ethical practices in the application of population genetics to forensics.