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The Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) organized a collaborative study on mutations of Y-chromosomal short tandem repeats (Y-STRs). New data from 2225 father-son duos and data from 44 previously published reports, corresponding to 25,729 duos, were collected and analyzed. Marker-specific mutation rates were estimated for 33 Y-STRs. Although highly dependent on the analyzed marker, mutations compatible with the gain or loss of a single repeat were 23.2 times more likely than those involving a greater number of repeats. Longer alleles (relatively to the modal one) showed to be nearly twice more mutable than the shorter ones. Within the subset of longer alleles, the loss of repeats showed to be nearly twice more likely than the gain. Conversely, shorter alleles showed a symmetrical trend, with repeat gains being twofold more frequent than reductions. A positive correlation between the paternal age and the mutation rate was observed, strengthening previous findings. The results of a machine learning approach, via logistic regression analyses, allowed the establishment of algebraic formulas for estimating the probability of mutation depending on paternal age and allele length for DYS389I, DYS393 and DYS627. Algebraic formulas could also be established considering only the allele length as predictor for DYS19, DYS389I, DYS389II-I, DYS390, DYS391, DYS393, DYS437, DYS439, DYS449, DYS456, DYS458, DYS460, DYS481, DYS518, DYS533, DYS576, DYS626 and DYS627 loci. For the remaining Y-STRs, a lack of statistical significance was observed, probably as a consequence of the small effective size of the subsets available, a common difficulty in the modeling of rare events as is the case of mutations. The amount of data used in the different analyses varied widely, depending on how the data were reported in the publications analyzed. This shows a regrettable waste of produced data, due to inadequate communicati

Syrine Boucherabine,1,* Rania Nassar,1,2,* Lobna Mohamed,1 Matthew Olsen,3 Fatma Alqutami,1 Shroque Zaher,1 Mahmood Hachim,1 Abdulmajeed Alkhajeh,4 Simon McKirdy,5 Rashed Alghafri,3,5– 7 Lotti Tajouri,3,5,7 Abiola Senok1 1College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, United Arab Emirates; 2Oral and Biomedical Sciences, School of Dentistry, College of Biomedical and Life Sciences, Cardiff University, Cardiff, UK; 3Faculty of Health Sciences and Medicine, Bond University, Robina, QLD, Australia; 4Dubai Health Authority, Dubai, United Arab Emirates; 5Harry Butler Institute, Murdoch University, Murdoch, WA, Australia; 6General Department of Forensic Sciences and Criminology, Dubai Police, Dubai, United Arab Emirates; 7Dubai Police Scientists Council, Dubai, United Arab Emirates*These authors contributed equally to this workCorrespondence: Abiola Senok, Mohammed Bin Rashid University of Medicine and Health Sciences, Building 14, Dubai Healthcare City, P. O. Box 505055, Dubai, United Arab Emirates, Tel +97143838717, Email abiola.senok@mbru.ac.aeBackground: As high touch wearable devices, the potential for microbial contamination of smart watches is high. In this study, microbial contamination of smart watches of healthcare workers (HCWs) was assessed and compared to the individual’s mobile phone and hands.Methods: This study was part of a larger point prevalence survey of microbial contamination of mobile phones of HCWs at the emergency unit of a tertiary care facility. Swabs from smart watches, mobile phones and hands were obtained from four HCWs with dual ownership of these digital devices. Bacterial culture was carried out for all samples and those from smart watches and mobile phones were further assessed using shotgun metagenomic sequencing.Results: Majority of the participants were females (n/N = 3/4; 75%). Although they all use their digital devices at work and believe that these devices coul

An intra and inter-laboratory study using the probabilistic genotyping (PG) software STRmix™ is reported. Two complex mixtures from the PROVEDIt set, analysed on an Applied Biosystems™ 3500 Series Genetic Analyzer, were selected. 174 participants responded. For Sample 1 (low template, in the order of 200 rfu for major contributors) five participants described the comparison as inconclusive with respect to the POI or excluded him. Where LRs were assigned, the point estimates ranging from 2 × 104 to 8 × 106. For Sample 2 (in the order of 2000 rfu for major contributors), LRs ranged from 2 × 1028 to 2 × 1029. Where LRs were calculated, the differences between participants can be attributed to (from largest to smallest impact): • varying number of contributors (NoC), • the exclusion of some loci within the interpretation, • differences in local CE data analysis methods leading to variation in the peaks present and their heights in the input files used, • and run-to-run variation due to the random sampling inherent to all MCMC-based methods. This study demonstrates a high level of repeatability and reproducibility among the participants. For those results that differed from the mode, the differences in LR were almost always minor or conservative.

A multiplex polymerase chain reaction (PCR) assay (RM-Yplex) was developed which is capable of simultaneously amplifying 13 recently introduced rapidly mutating Y-STR markers (RM Y-STRs). This multiplex assay is expected to aid human identity testing in forensic and other applications to improve differentiating unrelated males and allow separating related males. The 13 RM Y-STR markers included in the multiplex are: DYF387S1, DYF399S1, DYF403S1ab, DYF404S1, DYS449, DYS518, DYS526ab, DYS547, DYS570, DYS576, DYS612, DYS626 and DYS627. This study reflects the proof of concept to analyse all currently known RM Y-STRs simultaneously and describes the optimization of the multiplex assay. The RM-Yplex assay generated complete RM Y-STR profiles down to 62.5 pg of male template DNA, and from male–female DNA mixtures at all ratios tested. We herewith introduce and make available for widespread use in forensic and anthropological studies, an effective and sensitive single multiplex assay for simultaneous genotyping of 13 RM Y-STRs.

Differentiating male lineages using non-recombining Y-chromosomal genetic markers is highly informative for tracing human migration and for forensic studies. Recently, it has been shown that the level of male lineage resolution can be enhanced by analysing rapidly mutating (RM) Y-STRs. The aim of this study was to develop an allelic frequency database for Qatari population to evaluate the resolution power of 13 RM Y-STRs. The overall haplotype diversity (HD) was 100%. It was found that the markers which contributed the most toward high HD were DYF399S1 and DYF403S1a/b. Together with their value for paternal male relative differentiation, these RM Y-STRs will be a valuable asset for forensic casework. AMOVA test was performed between Qatari population in comparison to Gulf countries, Middle East, and several worldwide population data sets. FST values were also calculated. Geography was found to account considerably for the pattern of population sub structuring. The RM Y-STR markers showed remarkable haplotype resolution power in the Qatari population, high gene diversity and sufficient robustness for a diverse range of applications.

Development of a new multiplex comprising of 13 Rapidly Mutating Y STRs (RM Y-STR) is presented. The multiplex will aid investigating the human genetic structure of United Arab Emirates (UAE) populations and would also be used to investigate unresolved forensic cases in Dubai Forensic Laboratory. Thirteen markers have been included in the multiplex. A mini validation of the new multiplex has been carried out including specificity, sensitivity and mixture studies. These markers have been analysed in 600 male samples from UAE population. Allelic frequencies, haplotype diversity and discrimination capacity were determined for the 13 RM Y-STRs. Mutations pattern analysis of the RM Y-STR loci in a typical UAE family has also been carried out

The effectiveness of a rapidly mutating Y-STRs multiplex assay (RM Y-STRs) containing 13 RM Y-STR markers was compared with the AmpFℓSTR™ Yfiler™ PCR Amplification Kit (Yfiler) with conventional Y-STR markers for their efficiency in differentiating males within the same paternal lineage. Samples from 4 generations comprising 16 Dravidian males (15 father-son pairs) were analysed with both assays. Mutations were observed in 3 father-son pairs in the RM Y-STRs profiles while only 2 mutations were observed in the Y-filer profiles. Even though not many mutations were observed as anticipated, this study still emphasised the importance of RM Y-STRs when differentiation between males within the same paternal lineage is required and also indicated the need for mutation rates for different populations.