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After in vitro fertilization with a single embryo, the parents learned about being pregnant with twins in the 10th week with various indications that an embryonic mix-up could have taken place. The affected couple thus expressed the urgent desire for a clarification of parenthood considering an abortion. However, the prenatal test results would not have been available until the 14/15th week of pregnancy. Legally, then, severe physical or mental distress of the pregnant woman must be claimed by physicians to justify an abortion after the twelfth week. However, a lack of genetic relatedness could lead to serious psychological distress for the parents, making a pregnancy termination possible even after the twelfth week, which is discussed in this case study alongside the interdisciplinary team's ethical, legal, and medical considerations. For the invasive relationship testing, cultivated chorionic villi samples (CVS) from both unborn and saliva samples from the putative parents were genetically analyzed using classical short tandem repeats (STR) analysis. The perfect match of both CVS profiles suggested the occurrence of an unusual late twin shaft, for which, fortunately, parenthood could be confirmed. To our knowledge, this is the first report on a prenatal investigation of a suspected embryo mix-up after assisted reproductive technology (ART), in which parenthood should be fixed. We want to draw attention to this unthinkable scenario, which may increase in the future with ART-induced rising multiple pregnancies. [ABSTRACT FROM AUTHOR]

Microhaplotypes (MHs) consisting of multiple SNPs and indels on short stretches of DNA are new and interesting loci for forensic genetic investigations. In this study, we analysed 74 previously defined MHs in two of the populations that our laboratory provides with forensic genetic services, Danes and Greenlanders. In addition to the 229 SNPs that originally made up the 74 MHs, 66 SNPs and 3 indels were identified in the two populations, and 45 of these variants were included in new definitions of the MHs, whereas 24 SNPs were considered rare and of little value for case work. The average effective number of alleles (Ae) was 3.2, 3.0, and 2.6 in Danes, West Greenlanders, and East Greenlanders, respectively. High levels of linkage disequilibrium were observed in East Greenlanders, which reflects the characteristics of this population that has a small size, and signs of admixture and substructure. Pairwise kinship simulations of full siblings, half-siblings, first cousins, and unrelated individuals were performed using allele frequencies from MHs, STRs and SNPs from Danish and Greenlandic populations. The MH panel outperformed the currently used STR and SNP marker sets and was able to differentiate siblings from unrelated individuals with a 0% false positive rate and a 1.1% false negative rate using an LR threshold of 10,000 in the Danish population. However, the panel was not able to differentiate half-siblings or first cousins from unrelated individuals. The results generated in this study will be used to implement MHs as investigative markers for relationship testing in our laboratory. [ABSTRACT FROM AUTHOR]

This study examines the potential of hair shaft proteomic analysis to delineate genetic relatedness. Proteomic profiling and amino acid sequence analysis provide information for quantitative and statistically-based analysis of individualization and sample similarity. Protein expression levels are a function of cell-specific transcriptional and translational programs. These programs are greatly influenced by an individual's genetic background, and are therefore influenced by familial relatedness as well as ancestry and genetic disease. Proteomic profiles should therefore be more similar among related individuals than unrelated individuals. Likewise, profiles of genetically variant peptides that contain single amino acid polymorphisms, the result of non-synonymous SNP alleles, should behave similarly. The proteomically-inferred SNP alleles should also provide a basis for calculation of combined paternity and sibship indices. We test these hypotheses using matching proteomic and genetic datasets from a family of two adults and four siblings, one of which has a genetic condition that perturbs hair structure and properties. We demonstrate that related individuals, compared to those who are unrelated, have more similar proteomic profiles, profiles of genetically variant peptides and higher combined paternity indices and combined sibship indices. This study builds on previous analyses of hair shaft protein profiling and genetically variant peptide profiles in different real-world scenarios including different human hair shaft body locations and pigmentation status. It also validates the inclusion of proteomic information with other biomolecular substrates in forensic hair shaft analysis, including mitochondrial and nuclear DNA.

Nowadays, kinship testing is very common in forensic caseworks, but the power of autosomal short tandem repeats (A-STRs) may be limited in complex cases. X-Chromosome short tandem repeats (X-STRs), having a unique heritage mode, should be of special use in some deficient cases. To evaluate and compare the potential of A-STR and X-STR as supplement genetic markers in deficient kinship testing, we simulated 10,000 duos for each of 18 kinds of relationships involving full sibling, half-sibling, grandparent-grandchild, and uncle/aunt-nephew/niece. Loci from STRTyper10, PowerPlex 16, and Investigator Argus X-12 were studied in Southern Han Chinese and the distribution of likelihood ratio (LR) values was analysed. With the addition of the X-12 system, the distribution of LR values for the full sisters, paternal half-sisters, paternal grandmother-granddaughters, maternal aunt-nieces, and maternal aunt-nephews separated much more obviously from those of unrelated duos, and the effectiveness was 1.0000, 0.99865, 0.9991, 0.8996 and 0.9634, respectively, which was more efficient than A-STRs. For the individual duos with other relationships, the effects of adding X-STRs and A-STRs were similar. Therefore, for the Southern Han Chinese, X-STRs can be very useful in kinship testing involving full sisters, paternal half-sisters, paternal grandmother-granddaughters, and maternal aunt-nieces/nephews.

Nowadays, kinship testing is very common in forensic caseworks, but the power of autosomal short tandem repeats (A-STRs) may be limited in complex cases. X-Chromosome short tandem repeats (X-STRs), having a unique heritage mode, should be of special use in some deficient cases. To evaluate and compare the potential of A-STR and X-STR as supplement genetic markers in deficient kinship testing, we simulated 10,000 duos for each of 18 kinds of relationships involving full sibling, half-sibling, grandparent-grandchild, and uncle/aunt-nephew/niece. Loci from STRTyper10, PowerPlex 16, and Investigator Argus X-12 were studied in Southern Han Chinese and the distribution of likelihood ratio (LR) values was analysed. With the addition of the X-12 system, the distribution of LR values for the full sisters, paternal half-sisters, paternal grandmother-granddaughters, maternal aunt-nieces, and maternal aunt-nephews separated much more obviously from those of unrelated duos, and the effectiveness was 1.0000, 0.99865, 0.9991, 0.8996 and 0.9634, respectively, which was more efficient than A-STRs. For the individual duos with other relationships, the effects of adding X-STRs and A-STRs were similar. Therefore, for the Southern Han Chinese, X-STRs can be very useful in kinship testing involving full sisters, paternal half-sisters, paternal grandmother-granddaughters, and maternal aunt-nieces/nephews. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to identify the relationship between work-related, individual, and environmental factors and self-reported standing time during the workday.Design: Cross-sectional study design.Setting: Participants were recruited from a large, public university in the southeastern United States.Measures: Data were collected through an 87-item online survey using previously validated scales that assessed workplace standing time, demographic variables, work-related psychosocial factors, and workplace environment factors.Analysis: One-way analysis of variance, Pearson correlation coefficients, and nonparametric tests were used to determine univariate relationships between standing time and independent work-related variables and demographic factors.Results: Mean standing time among the sample (n = 502) was 72.49 minutes (standard deviation = 73.48) daily. There was a significant relationship between standing time and barrier self-efficacy for standing at work, self-regulation strategies, social norms, local connectivity in the workplace, overall connectivity in the workplace, and proximity of coworkers. Standing time was significantly higher for men, employees with an advanced degree, employees with a standing desk, and faculty.Conclusion: Health promotion researchers and practitioners should consider factors at multiple levels of influence when designing studies to explore workplace sedentary behavior. The findings regarding variations in workplace behavior by employee subgroups should be taken into consideration when designing future studies in the workplace. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to explore the relationship between ecological factors and occupational sedentary behavior (SB).Design: Cross-sectional online survey.Setting: Participants were employees recruited from a large, public university in the Southeastern United States from August to November 2016.Participants: The final sample included 527 (56% response rate) employees.Measures: Data were collected through an 87-item survey using previously validated scales that assessed occupational SB, perceived behavioral control, barrier self-efficacy, self-regulation strategies, organizational social norms, office environment, and worksite climate.Analysis: One-way analysis of variance analyses were used to determine differences in occupational SB by demographic factors. A multivariate regression model was used to determine significant ecological determinants of occupational SB.Results: Mean SB was 342.45 (standard deviation = 133.25) minutes. Significant differences in SB were found by gender, education, and employment classification. Barrier self-efficacy and workplace connectivity, which evaluates the spatial layout of the office setting that may impact mobility within the workplace, were significant predictors of SB in the multivariate model.Conclusion: Results from this study provide new information regarding the potential impact of workplace barriers and connectivity on occupational SB. The findings from this study support the inclusion of intervention modalities to minimize workplace barriers and increase workplace connectivity to increase workplace mobility and decrease SB. [ABSTRACT FROM AUTHOR]

Advances in massively parallel sequencing technology have enabled the combination of a much-expanded number of DNA markers (notably STRs and SNPs in one or combined multiplexes), with the aim of increasing the weight of evidence in forensic casework. However, when data from multiple loci on the same chromosome are used, genetic linkage can affect the final likelihood calculation. In order to study the effect of linkage for different sets of markers we developed the biostatistical tool ILIR, (Impact of Linkage on forensic markers for Identity and Relationship tests). The ILIR tool can be used to study the overall impact of genetic linkage for an arbitrary set of markers used in forensic testing. Application of ILIR can be useful during marker selection and design of new marker panels, as well as being highly relevant for existing marker sets as a way to properly evaluate the effects of linkage on a case-by-case basis. ILIR, implemented via the open source platform R, includes variation and genomic position reference data for over 40 STRs and 140 SNPs, combined with the ability to include additional forensic markers of interest. The use of the software is demonstrated with examples from several different established marker sets (such as the expanded CODIS core loci) including a review of the interpretation of linked genetic data. [ABSTRACT FROM AUTHOR]

There is a large number of applications where family relationships need to be determined from DNA data. In forensic science, competing ideas are in general verbally formulated as the two hypotheses of a test. For the most common paternity case, the null hypothesis states that the alleged father is the true father against the alternative hypothesis that the father is an unrelated man. A likelihood ratio is calculated to summarize the evidence. We propose an alternative framework whereby a model and the hypotheses are formulated in terms of parameters representing identity-by-descent probabilities. There are several advantages to this approach. Firstly, the alternative hypothesis can be completely general. Specifically, the alternative does not need to specify an unrelated man. Secondly, the parametric formulation corresponds to the approach used in most other applications of statistical hypothesis testing and so there is a large theory of classical statistics that can be applied. Theoretical properties of the test statistic under the null hypothesis are studied. An extension to trios of individuals has been carried out. The methods are exemplified using simulations and a real dataset of 27 Spanish Romani individuals. [ABSTRACT FROM AUTHOR]

Abstract: This paper is motivated by power considerations in connection with relationship testing. Given the true relationship between a set of individuals, a claimed relationship between the same individuals, and a set of genetic markers, we compute the power of exclusion, i.e., the probability that the genotypes will be incompatible with the claimed relationship. If exclusion is impossible, as will be the case if it is required for instance to distinguish between sibs and half sibs, we rather obtain the distribution of the likelihood ratio. The problem we are addressing can also be seen as a standard way of measuring the ability of a battery of tests to resolve claimed family relationships. In particular, simple exclusion probabilities are regularly calculated worldwide as a part of designing forensic marker sets. Our approach to these problems is guided by a natural way of calculating exclusion probabilities on a computer. We present a user friendly implementation for this as part of the R package paramlink, originally designed by one of the authors (MDV) for pedigree manipulations and likelihood computations. By doing so we are able to handle problems more challenging than we have seen in the literature. Specifically, we deal with complex pedigrees with arbitrary inbreeding and conditioning. We present examples for autosomal as well as X-linked markers and some formulae to validate the results. The examples indicate a wide range of applications. Details are presented for an immigration case where previously reported calculations are extended to account for possible inbreeding and known genotypes. The supplementary material includes a tutorial on how to perform these calculations in paramlink. [Copyright &y& Elsevier]

Cross-cultural research shows that while the concerns about organizational justice may be universal, operationalization of justice standards is highly particularistic (Greenberg 2001). The present study explores the dimensionality of organizational justice in the Indian context. Apart from procedural justice, interpersonal justice and informational justice, another justice dimension, labelled as empowerment justice, emerged during the study. Next, the study tests the relationships between justice dimensions and Organ's (1988) 5-factor conceptualization of organizational citizenship behaviour (OCB), namely helping, compliance, sportsmanship, courtesy and civic virtue behaviours. The perception of empowerment justice influences helping, compliance, sportsmanship, and civic virtue dimensions of OCB. Interpersonal justice significantly predicts courtesy behaviour. Implications for theory and practice are discussed. [ABSTRACT FROM AUTHOR]

Background: Genetic tests for kinship testing routinely reach likelihoods that provide virtual proof of the claimed relationship by typing microsatellites - commonly consisting of 12-15 standard forensic short tandem repeats (STRs). Single nucleotide polymorphisms (SNPs) have also been applied to kinship testing but these binary markers are required in greater numbers than multiple-allele STRs. However SNPs offer certain advantageous characteristics not found in STRs, including, much higher mutational stability, good performance typing highly degraded DNA, and the ability to be readily up-scaled to very high marker numbers reaching over a million loci. This article outlines kinship testing applications where SNPs markedly improve the genetic data obtained. In particular we explore the minimum number of SNPs that will be required to confirm pairwise relationship claims in deficient pedigrees that typify missing persons' identification or war grave investigations where commonly few surviving relatives are available for comparison and the DNA is highly degraded. Methods: We describe the application of SNPs alongside STRs when incomplete profiles or allelic instability in STRs create ambiguous results, we review the use of high density SNP arrays when the relationship claim is very distant, and we outline simulations of kinship analyses with STRs supplemented with SNPs in order to estimate the practical limit of pairwise relationships that can be differentiated from random unrelated pairs from the same population. Results: The minimum number of SNPs for robust statistical inference of parent-offspring relationships through to those of second cousins (S-3-3) is estimated for both simple, single multiplex SNP sets and for subsets of million-SNP arrays. Conclusions: There is considerable scope for resolving ambiguous STR results and for improving the statistical power of kinship analysis by adding small-scale SNP sets but where the pedigree is deficient the pairwise relationships must be relatively close. For more distant relationships it is possible to reduce chip-based SNP arrays from the million+ markers down to ∼7,000. However, such numbers indicate that current genotyping approaches will not be able to deliver sufficient data to resolve distant pairwise relationships from the limited DNA typical of the most challenging identification cases. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The mutation rate of single nucleotide polymorphisms (SNPs) is estimated to be 100,000 times lower than that of short tandem repeats (STRs), which makes SNPs very suitable for relationship testing. The SNPforID multiplex assay was the first SNP typing assay that was a real alternative to the commonly used STR kits in kinship and crime case work and the first SNP assay to be validated in a forensic laboratory accredited according to the ISO17025 standard. Methods: A total of 54 crime case samples were typed with the SNPforID multiplex assay. 30 samples from relationship cases were sequenced in selected SNP loci. Results: It was demonstrated that mixtures were easily detected with the SNPforID assay by analyzing the signal strengths of the detected alleles. Unusual imbalances in signal strengths that were observed in a few individuals could be explained by unexpected SNPs in one of the primer binding sites. A complicated relationship case with four closely related individuals is presented. Conclusion: Mixtures can be detected with bi-allelic SNPs. The SNPforID assay is a very useful supplement to the STR kits in relationship testing. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Purpose. Assessing food environments often requires using commercially available data. Disparate methods used for classifying food outlets in these databases call for creating a classification approach using common definitions. A systematic strategy for reclassifying food stores and restaurants, as they appear in commercial databases, into categories that differentiate the availability of healthy options is described here. Design and Setting. Commercially available data on food outlets including names, addresses, North American Industry Classification System codes, and associated characteristics was obtained for five New Jersey communities. Analysis. A reclassification methodology was developed using criteria and definitions from the literature to categorize food outlets based on availability of healthy options. Information in the database was supplemented by systematic Internet and key word searches, and from phone calls to food outlets. Results. The methodology resulted in 622 supermarket/grocery stores, 183 convenience stores, and 148 specialty stores in the original data to be reclassified into 58 supermarkets, 30 grocery stores, 692 convenience stores, and 115 specialty stores. Outlets from the original list of 1485 full-service restaurants and 506 limited-service restaurants were reclassified as 563 full- service restaurants and 1247 limited-service restaurants. Reclassification resulted in less than one-seventh the number of supermarkets and grocery stores, more than three times the number of convenience stores, and twice as many limited-service restaurants'a much less healthy profile than the one generated by using exclusively the commercial databases. Conclusion. An explicit and replicable strategy is proposed for reclassifying food outlets in commercial databases into categories that differentiate on the basis of healthy food availability. The intent is to contribute towards building a consensus among researchers on definitions used in public health research for characterizing different types offood outlets. [ABSTRACT FROM AUTHOR]

Abstract: Six case work examples are presented, where the individuals were typed for 15 autosomal short tandem repeats (STRs) and 49 autosomal single nucleotide polymorphisms (SNPs). The 15 STRs were typed with the AmpFlSTR Identifiler PCR Amplification Kit and the 49 SNPs were typed with the SNPforID multiplex assay. The six cases included two duos, two trios and two cases, where the alleged father was not available for testing and one or two of his close relatives were tested instead. The SNP investigation was more informative than the STR investigation in all six cases. In two cases, the alleged father would have been falsely included based on the STR results, while the SNP results showed that the alleged father was not the true parent. These case work examples underline the importance of performing supplementary investigations in selected cases and demonstrate the usefulness of the SNPforID multiplex assay. [Copyright &y& Elsevier]

Relationship testing laboratories provide genetic evidence to support or refute claims of kinship between U.S. citizen petitioners and potential immigrant beneficiaries. One female beneficiary presented a male amelogenin type and alleles at 15 autosomal loci that were identical to an alleged brother's. Laboratory records showed that her alleged father had petitioned to have 15 children emigrate from Ghana. The petitioner's 15 paternity indices exceeded 10, but the children shared only four short tandem repeat (STR) profiles, suggesting fraudulent reuse of genotypes in this alleged pedigree (AP). To determine the extent of this 'genotype recycling,' I examined the laboratory's 555 APs from Ghana and 532 control APs from Nigeria. Seventeen Ghanaian APs (3.1%) but no Nigerian APs showed genotype recycling. Of 90 tested people in the 17 APs, 56 shared identical STR profiles with others in their AP. Of these 56 people, 10 were petitioners with unexpectedly high parentage indices. Seven of 56 had amelogenin types that disagreed with their declared genders. Database searches for identical multilocus genotypes in allegedly different people would best detect this fraud. [ABSTRACT FROM AUTHOR]

Abstract: The Paternity Testing Commission (PTC) of the International Society for Forensic Genetics has taken up the task of establishing the biostatistical recommendations in accordance with the ISO 17025 standards and a previous set of ISFG recommendations specific to the genetic investigations in paternity cases. In the initial set, the PTC recommended that biostatistical evaluations of paternity are based on a likelihood ratio principle – yielding the paternity index, PI. Here, we have made five supplementary biostatistical recommendations. The first recommendation clarifies and defines basic concepts of genetic hypotheses and calculation concerns needed to produce valid PIs. The second and third recommendations address issues associated with population genetics (allele probabilities, Y-chromosome markers, mtDNA, and population substructuring) and special circumstances (deficiency/reconstruction and immigration cases), respectively. The fourth recommendation considers strategies regarding genetic evidence against paternity. The fifth recommendation covers necessary documentation, reporting details and assumptions underlying calculations. The PTC strongly suggests that these recommendations should be adopted by all laboratories involved in paternity testing as the basis for their biostatistical analysis. [Copyright &y& Elsevier]

Purpose. To examine the relationship between readiness to change exercise behavior and smoking behavior, stratified by gender. Methods. A cross-sectional survey of those inhabitants of Hikami, Japan, who were 30 years of age or older (n 511,708). The response rate was 82.1%. Chi-squared tests and analysis of variance were used to evaluate differences in characteristics by smoking behavior, and the odds ratio (OR) was calculated to examine the relationship while controlling for possible confounding factors such as age, body mass index, and health consciousness. Results. Even when controlling for confounding factors, the relationship between the two behaviors differed according to gender. Among males, ex-smokers were more likely to be motivated to exercise (OR, 1.14; 95% confidence interval [CI], .95–1.36), whereas among females, smokers were more likely to be motivated to exercise (OR, .40; 95% CI, .34–.48). Discussion. Despite some limitations, the findings suggest that gender should be used as a stratification variable when discussing the relationship between smoking and exercise behaviors. [ABSTRACT FROM AUTHOR]

Forensic DNA profiling is used in various circumstances to evaluate support for two competing propositions with the assignment of a likelihood ratio. Many software implementations exist that tackle a range of inference problems spanning identification and relationship testing. We propose a flexible likelihood ratio framework that caters to inference problems in forensic genetics. The framework allows for investigation of the degree of support for the contribution of multiple persons to multiple samples allowing for persons to be related according to a pedigree, including inbred relationships. We explain how a number of routine as well as more complex problems can be treated within this framework. • Pedigrees and mixtures are combined in a likelihood ratio method. • Kinship testing can be based on incomplete and mixed profiles. • Contribution to a mixture can be tested when contributors are related. • Evidence can be combined across multiple samples. [ABSTRACT FROM AUTHOR]

This study examines the potential of hair shaft proteomic analysis to delineate genetic relatedness. Proteomic profiling and amino acid sequence analysis provide information for quantitative and statistically-based analysis of individualization and sample similarity. Protein expression levels are a function of cell-specific transcriptional and translational programs. These programs are greatly influenced by an individual's genetic background, and are therefore influenced by familial relatedness as well as ancestry and genetic disease. Proteomic profiles should therefore be more similar among related individuals than unrelated individuals. Likewise, profiles of genetically variant peptides that contain single amino acid polymorphisms, the result of non-synonymous SNP alleles, should behave similarly. The proteomically-inferred SNP alleles should also provide a basis for calculation of combined paternity and sibship indices. We test these hypotheses using matching proteomic and genetic datasets from a family of two adults and four siblings, one of which has a genetic condition that perturbs hair structure and properties. We demonstrate that related individuals, compared to those who are unrelated, have more similar proteomic profiles, profiles of genetically variant peptides and higher combined paternity indices and combined sibship indices. This study builds on previous analyses of hair shaft protein profiling and genetically variant peptide profiles in different real-world scenarios including different human hair shaft body locations and pigmentation status. It also validates the inclusion of proteomic information with other biomolecular substrates in forensic hair shaft analysis, including mitochondrial and nuclear DNA., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Abstract: The presence of the tri-allelic TPOX genotypes represents a new finding about the Dominican Population origins. The STRs in our population have been characterized in our previous investigation, now we are beginning the process to confirm the true components of our ethnical structure. About 90% of the contemporary Dominican Population has African ancestry or has African roots, for this reason we strongly consider the nature of the tri-allelic TPOX genotypes as African origins. In this work, we report tri-allelic TPOX genotypes by routine relationship testing using PowerPlex 16 (Promega Corporation) kits. [Copyright &y& Elsevier]

Annually, members of the English Speaking Working Group of the International Society for Forensic Genetics are invited to participate in a Relationship Testing Workshop. In 2015, 64 laboratories participated. Here, we present the results from the 2015 workshop, which included relationship testing of blood samples from a mother, two children and an alleged father. Furthermore, the laboratories filled in a questionnaire concerning the laboratory strategies and routines. Finally, the laboratories were encouraged to do a paper challenge concerning the relationship between a child (boy) and an alleged grandfather with statistical calculations including results of autosomal STRs and Y-chromosomal STRs. The paper challenge showed large variations in the biostatistical calculations in cases of genetic inconsistencies observed in Y-chromosomal STR typing results. [ABSTRACT FROM AUTHOR]

Abstract: We present the results of the 2013 Relationship Testing Workshop of the English Speaking Working Group of the International Society for Forensic Genetics. A total of 56 laboratories participated. The exercise included relationship testing of blood samples from an alleged mother and two children. Furthermore, the laboratories filled in a questionnaire concerning the laboratory strategies and routines. Finally, the laboratories were encouraged to do a paper challenge with statistical calculations including autosomal STRs and X-chromosomal STRs. In the relationship testing exercise, the two children were truly a biological child and a biological grandchild of the alleged mother. The exercise revealed that the use of X-STRs was informative and excluded the alleged mother as the mother of her grandchild. The paper challenge showed large variations in the biostatistical calculations in cases of rare events such as possible silent alleles, genetic inconsistencies and in calculations involving X-chromosomal STR genotyping results. [Copyright &y& Elsevier]

Abstract: We present the results of the 2011 Relationship Testing Workshop of the English Speaking Working Group of the International Society for Forensic Genetics. A total of 62 laboratories participated. The exercise included relationship testing of blood samples from a man and two children. Assuming that the man is the biological father of both children, the laboratories were asked to investigate if the results were in favour or against that the children were half or full siblings. Furthermore, the laboratories filled out a questionnaire concerning the laboratory strategies and routines. Finally, the laboratories were encouraged to do a paper challenge with statistical calculations. The relationship testing exercise revealed that the use of mtDNA and X-STR was informative and excluded the possibility of full siblings. In the questionnaire, most laboratories (77%) indicated that a single autosomal STR kit was used in all paternity cases. However, >60% of the laboratories had three or more autosomal STR kits available for paternity testing. The paper challenge showed large variations in the biostatistical calculations in cases of rare events such as a rare allele and when a single genetic inconsistency was observed. [Copyright &y& Elsevier]

Abstract: Genetic markers represent a very important tool in forensic identification caseworks, in family relationships as well as in criminal analysis. The discrimination power of current genetic polymorphisms is so high that the inferential process can be efficiently used even in cases where direct knowledge on the genetic data of one of the terms in comparison is lacking. However in some cases despite the use of Probabilistic Expert Systems (FINEX) it is not always possible to achieve an acceptable percentage of paternity probability. Certainly one of these cases is the request to verify the relationship between two half-siblings of different gender in the absence of data from parents. In these cases it is not possible to use important tools such as polymorphisms of sexual chromosomes, so that the only possible approach is to increase the number of autosomal STRs. Therefore the authors decided to investigate 36 pairs of half-siblings with known relationships from different parts of Italy, using a high number of autosomal STRs. The aim of this study is to verify whether, increasing the number of autosomal STRs analyzed, the application of PES allows to achieve an acceptable value of paternity probability without availability of parents’ profiles. [Copyright &y& Elsevier]