Publications by authors named "Arwin Ralf"

Y-chromosomal short tandem repeats (Y-STRs) at rapidly mutating (RM) loci have been suggested as tools for differentiating paternally related males. RMplex is a recently developed system that incorporates 26 RM loci and four fast-mutating (FM) loci, targeting 44 male-specific loci. Here, we evaluated the RMplex by estimating Y-STR mutation rates and the overall differentiation rates for 542 Korean father-son pairs, as well as the genetic population values for 409 unrelated males.

View Article and Find Full Text PDF

Although national criminal offender DNA databases (NCODDs) including autosomal short tandem repeats (STRs) have been a successful tool to identify criminals for decades in many countries, yet there are many criminal cases they cannot solve. In cases with mixed male-female samples, particularly sexual assault, expanding NCODDs with Y-chromosomal STR (Y-STR) profiles allows database matching in the absence of autosomal STR profiles. Although Y-STR matches are not individual-specific, this can be largely overcome with rapidly mutating Y-STRs (RM Y-STR) allowing separation of paternally related men.

View Article and Find Full Text PDF

Y-chromosomal short tandem repeats (Y-STRs) are widely used in forensic, genealogical, and population genetics. With the recent increase in the number of rapidly mutating (RM) Y-STRs, an unprecedented level of male differentiation can be achieved, widening and improving the applications of Y-STRs in various fields, including forensics. The growing complexity of Y-STR data increases the need for automated data analyses, but dedicated software tools are scarce.

View Article and Find Full Text PDF

Motivation: We introduce SMapper, a novel web and software tool for visualizing spatial prevalence data of all types including those suffering from incomplete geographic coverage and insufficient sample sizes. We demonstrate the benefits of our tool in overcoming interpretational issues with existing tools caused by such data limitations. We exemplify the use of SMapper by applications to human genotype and phenotype data relevant in an epidemiological, anthropological and forensic context.

View Article and Find Full Text PDF
Article Synopsis
  • * This study analyzed mutation rates in 9379 pairs of men across 30 RM Y-STRs and found significant differences in mutation rates compared to standard Y-STRs, revealing higher differentiation rates among more distantly related individuals.
  • * The results indicate that RM Y-STRs can accurately predict the degree of patrilineal relatedness, with potential to greatly enhance forensic Y-chromosome analysis compared to traditional methods.
View Article and Find Full Text PDF

Rapidly mutating Y chromosomal short tandem repeat markers (RM Y-STRs) -characterized by at least one mutation per 100 generations- are suitable for differentiating both related and unrelated males. The recently introduced multiplex method RMplex allows for the efficient analysis of 30 Y-STRs with increased mutation rates, including all 26 currently known RM Y-STRs. While currently available RM Y-STR mutation rates were established mostly from European individuals, here we applied RMplex to DNA samples of 178 genetically confirmed father-son pairs from East Asia.

View Article and Find Full Text PDF

The discovery of rapidly mutating (RM) Y-STRs started to move the field of forensic Y-STR analysis from male lineage identification towards male individual identification. Previously, the forensic value of RM Y-STRs for differentiating male relatives was limited due to the modest number of 13 identified RM Y-STRs. Recently, new RM Y-STRs were discovered, with strong expectations for significantly improving male relative differentiation; however, empirical evidence is missing yet.

View Article and Find Full Text PDF

Y-chromosomal short tandem repeats (Y-STRs) with high mutation rates are recognized as valuable genetic markers for differentiating paternally related men, who typically cannot be separated with standard Y-STRs, and were shown to provide paternal lineage differentiation on a higher resolution level than standard Y-STRs. Both features make Y-STRs with high mutation rates relevant in criminal casework, particularly in sexual assault cases involving highly unbalanced male-female DNA mixtures that often fail autosomal forensic STR profiling for the male donor. Previously, the number of known Y-STRs with mutation rates higher than 10 per locus per generation termed rapidly mutating Y-STRs (RM Y-STRs) was limited to 13, which has recently been overcome by the discovery and characterization of 12 additional RM Y-STRs.

View Article and Find Full Text PDF
Article Synopsis
  • * Using the HIrisPlex-S system and targeted massively parallel sequencing (MPS), researchers successfully predicted physical traits like eye, hair, and skin color from the two-person DNA mixture.
  • * The success of this method hinges on factors such as reference DNA analysis from the victim, nearly equal DNA contributions from both parties, and the advanced quantitative analysis capabilities of MPS; this approach could enhance future investigations in cases involving mixed DNA samples.
View Article and Find Full Text PDF

Short tandem repeat polymorphisms on the male-specific part of the human Y-chromosome (Y-STRs) are valuable tools in many areas of human genetics. Although their paternal inheritance and moderate mutation rate (~10 mutations per marker per meiosis) allow detecting paternal relationships, they typically fail to separate male relatives. Previously, we identified 13 Y-STR markers with untypically high mutation rates (>10 ), termed rapidly mutating (RM) Y-STRs, and showed that they improved male relative differentiation over standard Y-STRs.

View Article and Find Full Text PDF

Forensic DNA Phenotyping (FDP) provides the ability to predict externally visible characteristics from minute amounts of crime scene DNA, which can help find unknown perpetrators who are typically unidentifiable via conventional forensic DNA profiling. Fundamental human genetics research has led to a better understanding of the specific DNA variants responsible for physical appearance characteristics, particularly eye, hair, and skin color. Recently, we introduced the HIrisPlex-S system for the simultaneous prediction of eye, hair, and skin color based on 41 DNA variants generated from two forensically validated SNaPshot multiplex assays using capillary electrophoresis (CE).

View Article and Find Full Text PDF

Y-chromosomal haplogroups assigned from male-specific Y-chromosomal single nucleotide polymorphisms (Y-SNPs) allow paternal lineage identification and paternal bio-geographic ancestry inference, both being relevant in forensic genetics. However, most previously developed forensic Y-SNP tools did not provide Y haplogroup resolution on the high level needed in forensic applications, because the limited multiplex capacity of the DNA technologies used only allowed the inclusion of a relatively small number of Y-SNPs. In a proof-of-principle study, we recently demonstrated that high-resolution Y haplogrouping is feasible via two AmpliSeq PCR analyses and simultaneous massively parallel sequencing (MPS) of 530 Y-SNPs allowing the inference of 432 Y-haplogroups.

View Article and Find Full Text PDF

Correct identification of different human epithelial materials such as from skin, saliva and vaginal origin is relevant in forensic casework as it provides crucial information for crime reconstruction. However, the overlap in human cell type composition between these three epithelial materials provides challenges for their differentiation and identification when using previously proposed human cell biomarkers, while their microbiota composition largely differs. By using validated 16S rRNA gene massively parallel sequencing data from the Human Microbiome Project of 1636 skin, oral and vaginal samples, 50 taxonomy-independent deep learning networks were trained to classify these three tissues.

View Article and Find Full Text PDF

Next-generation sequencing (NGS) technologies offer immense possibilities given the large genomic data they simultaneously deliver. The human Y-chromosome serves as good example how NGS benefits various applications in evolution, anthropology, genealogy, and forensics. Prior to NGS, the Y-chromosome phylogenetic tree consisted of a few hundred branches, based on NGS data, it now contains many thousands.

View Article and Find Full Text PDF

Monozygotic (MZ) twins share the same STR profile, demonstrating a practical problem in forensic casework. DNA methylation has provided a suitable resource for MZ twin differentiation; however, studies addressing the forensic feasibility are lacking. Here, we investigated epigenetic MZ twin differentiation from blood under the forensic scenario comprising i) the discovery of candidate markers in reference-type blood DNA via genome-wide analysis, ii) the technical validation of candidate markers in reference-type blood DNA using a suitable targeted method, and iii) the analysis of the validated markers in trace-type DNA.

View Article and Find Full Text PDF

Pakistan harbors 16 major ethnic groups including Punjabis (56% of total population) and Kashmiri (6% of total population). Here, we report data of 17 Y-chromosomal short tandem repeats (Y-STRs) genotyped with the AmpFlSTR Y-filer™ PCR Amplification kit in 94 Punjabis and 101 Kashmiris. The estimated haplotype diversity was higher in Punjabis (0.

View Article and Find Full Text PDF

Y-chromosomal short tandem repeat (Y-STR) markers are commonly used in forensic genetics. Male-specific haplotypes provided by commercial Y-STR kits allow discriminating between many - but not all - unrelated men, while they mostly fail to separate related ones. Aiming to improve male relative and paternal lineage differentiation, a set of 13 rapidly-mutating (RM) Y-STRs was previously identified and introduced to forensic Y-chromosome analysis.

View Article and Find Full Text PDF

Whole mitochondrial (mt) genome analysis enables a considerable increase in analysis throughput, and improves the discriminatory power to the maximum possible phylogenetic resolution. Most established protocols on the different massively parallel sequencing (MPS) platforms, however, invariably involve the PCR amplification of large fragments, typically several kilobases in size, which may fail due to mtDNA fragmentation in the available degraded materials. We introduce a MPS tiling approach for simultaneous whole human mt genome sequencing using 161 short overlapping amplicons (average 200 bp) with the Ion Torrent Personal Genome Machine.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

SNPs from the non-recombining part of the human Y chromosome (Y-SNPs) are informative to classify paternal lineages in forensic, genealogical, anthropological, and evolutionary studies. Although thousands of Y-SNPs were identified thus far, previous Y-SNP multiplex tools target only dozens of markers simultaneously, thereby restricting the provided Y-haplogroup resolution and limiting their applications. Here, we overcome this shortcoming by introducing a high-resolution multiplex tool for parallel genotyping-by-sequencing of 530 Y-SNPs using the Ion Torrent PGM platform, which allows classification of 432 worldwide Y haplogroups.

View Article and Find Full Text PDF
Article Synopsis
  • Y-chromosomal short tandem repeats (Y-STRs) are used to test paternal relationships and identify male lineage, but the standard Yfiler set has limitations.
  • A study involving 52 centers analyzed 13 rapidly mutating Y-STRs in 14,644 males from 111 populations, leading to over 99% successful individual identification.
  • The results showed extremely high haplotype diversity, minimal sharing among populations, and significant improvements in relationship differentiation when using RM Y-STRs compared to traditional methods.
View Article and Find Full Text PDF

Genomic prediction of the extreme forms of adult body height or stature is of practical relevance in several areas such as pediatric endocrinology and forensic investigations. Here, we examine 770 extremely tall cases and 9,591 normal height controls in a population-based Dutch European sample to evaluate the capability of known height-associated DNA variants in predicting tall stature. Among the 180 normal height-associated single nucleotide polymorphisms (SNPs) previously reported by the Genetic Investigation of ANthropocentric Traits (GIANT) genome-wide association study on normal stature, in our data 166 (92.

View Article and Find Full Text PDF