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Requests for solving complex kinship casework involving at least one female are increasing and in these circumstances the analysis of X-chromosomal STR markers plays a relevant role. Actually, it is well known the superior statistical power of X-STRs compared to autosomal markers in solving relationship when two sisters or half-sisters are involved and none of parents is available, in maternity testing or in cases involving close relatives as alternative putative fathers. In addition, the possibility to amplify more loci simultaneously and the strategy based on the analysis of four linkage groups to obtain the X-haplotype provide a powerful and validated tool. Nevertheless, haplotypes frequency distribution in different populations is still needed for calculation of probabilities in relationship testing. Published haplotype frequencies from German population data are available, but in different caseworks we found unreported X-haplotypes. To enlarge the forensic X-chromosome database, we present haplotype frequencies and other parameter of forensic interest obtained from 200 anonymous DNA samples of unrelated Italian males for the four linkage groups included in the Investigator Argus X-12 kit. From the comparison of the Italian sample haplotype frequencies with other populations, significant genetic distances were found with Asian and African populations, but not with Europeans. Finally, casework examples of complex kinship analysis are presented., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Microsatellites or short tandem repeats (STRs) markers are important tools for mapping disease-causing genes by linkage, for performing investigations in forensic medicine, for population genetic studies and for studying genetic modifications in tumors. In forensic applications neoplastic tissues can be used as a source of genetic information for personal identification or paternity testing when no other specimen is available. Cancer tissues can show microsatellite instability (MSI) and loss of heterozygosity (LOH) also for the STRs used in the forensic field. In this study, we screened 56 sporadic gastrointestinal carcinomas in order to provide further data for the evaluation of the incidence of allelic alterations for 15 STR loci and the suitability of using cancerous tissues in forensic applications. Sixty-six percent of the cancerous tissues were found to possess allelic alterations of the microsatellites analyzed with a high incidence of MSI-L (microsatellite instability low) when compared to the corresponding normal tissue. The most frequently altered loci were D18S51, VWA, and FGA. From a forensic perspective, great care must be taken in evaluating the DNA typing results obtained from cancerous tissue samples.

Autosomal polymorphisms (STRs) or Y-Chromosome polymorphisms (Y-STRs) are usually used for the study and deconvolution of mixed DNA profiles in forensic genetics, accompanying data interpretation with biostatistical evaluations (e.g., RMP, RMNE, LR). Sometimes, however, some mixed DNA profiles are so complex that autosomal and Y markers are not sufficient for correct discrimination and identification. In this work is reported a robbery case in which the analysis of the polymorphic markers of the X Chromosome (X-STRs) was applied to the mixed profiles obtained from the traces. This falls outside the classic use of the X-STRs. Indeed, the aim of the authors is to encourage the usage of X-STRs not only in parental relationships, but also in pure forensic cases for interpreting complex mixed DNA profiles, since their application in case resolution could be more decisive than autosomal STRs and Y-STRs. [ABSTRACT FROM AUTHOR]

Abstract: CYP2D6 polymorphism, recently studied by minisequencing analysis, lets physicians know the phenotype of a patient or a worker, allowing the correct therapy or the development of a preventive occupational medicine, since recently evidence in favour of CYP2D6 phenotype and pesticide exposure interaction in parkinsonism has been described. In the forensic field the usefulness of CYP2D6 polymorphism is known, in the future joining the classical autopsy with the forensic genetic laboratory. With the aim to genotype a rural area where the pesticides are widely employed, we studied a population sample from Ravenna in the North of Italy. We also analyzed an African population sample, in order to characterize a geographic area where the CYP2D6 ultra metabolizer phenotype is more frequent, to compare the genetic makeup and to enlarge the CYP2D6 population data. A total of 122 individuals resident in the Ravenna area and 65 individuals from North and East Africa were tested by minisequencing method for 11 SNPs positions together with gene deletions and duplications. The Ravenna population, even if in agreement with population data available up to date, showed a slightly higher rate of non-functional alleles defining the poor metabolizer phenotype. African population genotyping confirms the higher rate of gene duplication already reported. The obtained data highlight the need to know the genetic background of a geographical area related to the economical and social setting to address the healthy policies in the occupational medicine nevertheless considering the today admixed population structure. [Copyright &y& Elsevier]