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The purpose of this paper is to formulate recommendations for the disclosure of biological traces in the laboratory and the handling of forensic evidence submitted for identification tests, recommended by the Polish Speaking Working Group of the International Society for Forensic Genetics. The paper organizes the knowledge of the most relevant stages of preliminary analysis of biological traces based on both literature sources and those resulting from years of research practice. Recommendations formulated in the course of multi-stage expert consultations contained in this study should be used in the development of laboratory procedures applied during the execution., (Copyright © 2024 by PTMSiK.)

Among a large number of expert opinions concerning disputed paternity cases prepared in the Chair of Forensic Medicine and Medico-Legal Toxicology, Silesian University of Medicine, Katowice, there were those in which the use of a standard 15 autosomal loci AmpFISTR Identifiler kit was not sufficient to give an unequivocal opinion. The authors report a case of disputed paternity, in which the analysis done by applying an AmpFISTR Identifiler kit showed no paternity heredity in 2 loci in the child. As allele distribution did not exclude mutation, further genetic markers were determined using PowerPlex ESX and FFFL kits and further three exclusions were found. Moreover, X-chromosome loci were determined using a MentypeAngusX8 test, which confirmed the exclusion of paternity in further 4 loci.

With respect to epidemiology of carbon monoxide poisonings, the diagnostic management of poisonings caused by this xenobiotic is among the fundamental objectives of forensic toxicology. In forensic practice, to determine carbon monoxide, colorimetric and spectrophotometric methods, as well as gas chromatography are used. Based on literature data and their own experience, the authors discuss analytical methods universally applied in determinations of carbon monoxide in postmortem blood. The advantages and disadvantages, as well as the cause of errors resulting from the specificity of the examined material (postmortem blood) are indicated.

The report present the results of population studies of 11 STR loci: D16S5539, D7S820, D13S317, CSF1PO, TPOX, TH01, F13A01, FESFPS, VWA, F13B, LPL originating from samples examined in Laboratory of Biological traces, Chair and Department of Forensic Medicine, Silesian Medical University. The examinations were performed in the group of 455 non-consanguinated adults, men and women, from Upper Silesia. The purpose of the investigation was to study the distribution of allele frequencies of 11 short tandem repeat representative sample of the Upper Silesia (Poland) population, to show genetic balance in agreement with Hardy-Weinberg's law for the studied population and to compare homogeneity of the usefulness of 11 STR genetic markers for paternity testing and forensic identification purposes. Genomic DNA was isolated from blood samples and swabs from oral cavity by The Blood DNA Prep Plus kit (A&A Biotechnology) and EZ1 DNA tissue Kit for the use on the BioRobot EZ1. All reactions were carried out according to the manufacturer's recommendations (Silver Stain Detection, Promega). POR amplification was performed following the instructions of the GenePrint STR System kit using a GeneAmp PCR System 2700 Thermal Cykler. PCR products and Promega Ladders were separated by vertical electrophoresis on 6% denaturing polyacrilamide gel (Amresco), electrophoresis and visualized by silver staining (Promega Corporation). Allele frequencies, the values of heterozygosity (Ht), polymorphism information content (PIC), power of discrimination(PD), power of exclusion (PE), paternity index (PI), and matching probability (PM) were calculated using FatRec by Dudek's program and TFPGA of Miller. The concordance with HWE was evaluated using the chi-square test. The compared statistic parameters, which make an important component of research work and opinionating, show that 11 STR loci constitutes a very useful tool for individual identification in crime research and in putative paternity research.

The paper shows the results of studies on locus F13B in the population of Upper Silesia. The examinations were performed in the group of 433 unrelated adults. The following genes frequencies were observed: F13B*6=0.0982; F13B*7=0.0127; F13B*8=0.2286, F13B*9=0.2494, F13B*10=0.4042, F13B*11=0.0046 and F13B*12=0.0023. DNA was isolated using Blood DNA Prep Plus of A&A Biotechnology. Amplification was carried out in a Perkin Elmer GeneAmp PCR System 2400 thermal cycler, using GenePrint STR System F13B8 (1q31-q32.1) of Promega Corporation, Madison, WI, USA. PCR products were electrophoretically separated by high-resolution polyacrylamide gel - GDG of Perkin Elmer. Gels were stained by the silver method. The X2 test, exact and Carmody test were used for statistical analysis. The identification values of the system were: PD, Ht, PM, MEC, PIC, MEP The analysis of the studies showed that the examined population was in the genetic equilibrium conformable to the Hardy-Weinberg's principle. The estimated gene frequencies were similar to those observed in five other Polish populations. The population of Poland was demonstrated to be homogenous.

The authors present the results of VNTR-PCR DNA polymorphism of three STR loci. Gene profiles were determined in experimental spots of blood from 2 or 3 unrelated individuals mixed in the ratios 1:1-1:100. Genotypes were successfully determined in mixed blood spot samples of ratios 1:1-1:60. A small amount of DNA in all those samples manifested a light electrophoretic staining. The electrophoretic band disappearance in the mixed blood spot samples of high dilution (<1:70) did not allow for determination of their genotypes. In the paper the results obtained while identifying biological traces from sexual offences in which mixed DNA occurred have been also presented.

In the paper the authors present results of the postmortem examination of the burnt body of an unidentified young man NN, who was suspected of being kidnapped, held in custody and finally burnt. During the autopsy dental identification was carried out and its results were compared to the dental card of the chosen man. Toxicological examinations of alcohol, CO, drugs and medicines were negative. Additionally, for individual identification, the analysis of blood DNA polymorphism was carried out in the following loci: CSF1PO, TPOX, TH01, F13A01, VWA, F13B, HPRTB, D16S539, D7S820, D13S317 (STR systems), D1S80 and also DQA1, LDLR, GYPA, HBGG, D7S8, GC. The results of the DNA polymorphism in the deceased were compared to those obtained in putative parents. Statistical analysis of the obtained results of the DNA analysis allowed to find out that the man NN was the son of H.E. and R.E. This comprehensive medico-legal examination allowed for identification of the deceased.

This paper shows the results of locus LPL in the population of Upper Silesia. The examinations were performed in a group of 147 unrelated adults. The following gene frequencies were observed: LPL*9 = 0.0578; LPL* 10 = 0.4048; LPL* 11 = 0.2517, LPL* 12 = 0.2449 i LPL* 13 = 0.0408. DNA was isolated using Blood DNA Prep Plus of A&A Biotechnology. Amplification was carried out in a Perkin Elmer GeneAmp PCR System 2400 thermal cycler, using the GenePrint STR System LPL (8p22) of Promega Corporation, Madison, WI, USA. PCR products were electrophoretically separated by high-resolution polyacrylamide gel--GDG of Perkin Elmer. Gels were stained by the silver method. Test chi 2, exact and Carmody's were used for statistical estimation. The identification values of the system are: PD, Ht, PM, MEC, PIC, MEP. The analysis of studies has shown that the examined population is in the genetic equilibrium conformable to the Hardy-Weinberg's principle. The estimated gene frequencies are similar to those observed in two Polish populations.