Forensic Science International-genetics 

About: Forensic Science International-genetics is an academic journal published by Elsevier BV. The journal publishes majorly in the area(s): Population & Allele frequency. It has an ISSN identifier of 1872-4973. Over the lifetime, 2371 publications have been published receiving 65601 citations. The journal is also known as: FSI & FSI. Genetics.

Y chromosome haplotype reference database (YHRD): update.

Abstract: The freely accessible YHRD (Y Chromosome Haplotype Reference Database, www.yhrd.org) is designed to store Y chromosome haplotypes from global populations and had replaced three earlier database versions collecting European, Asian and US American Y chromosomes separately. The focus is to disseminate haplotype frequency data to forensic analysts, researchers, and to everyone who is interested in historical and family genetics. YHRD considers reduction of the available number of polymorphisms on the Y chromosome to a uniform data string of 11 highly variable Y-STR loci as an efficient way to rapidly screen many world populations and to make their Y chromosome profiles comparable. Typing of the YHRD 11-locus core set is facilitated by commercial products, namely diagnostic PCR kits, and endorsed by scientific and forensic analyst's societies as ISFG or SWGDAM. YHRD is structured by the assignment of each submitted population sample to a set of populations sharing a common linguistic, demographic, genetic or geographic background (metapopulations). This principle facilitates the statistical evaluation of haplotype matches due to a significant enlargement of sample sizes. With the rapid growth of the database the definition of homogeneous metapopulations is now also feasible solely on the basis of the genetic data as exemplified for the whole dataset of YHRD, release 19 (August 2006). Large sample numbers within genetically defined metapopulations also allows the development of biostatistical methods to estimate the frequency of unobserved or rare haplotypes ("haplotype frequency surveying method"). Essential for the YHRD project is its collaborative character relying on the engagement of individual laboratories to make their data accessible via YHRD and to share the YHRD standards regarding data quality.

The HIrisPlex system for simultaneous prediction of hair and eye colour from DNA

Abstract: Recently, the field of predicting phenotypes of externally visible characteristics (EVCs) from DNA genotypes with the final aim of concentrating police investigations to find persons completely unknown to investigating authorities, also referred to as Forensic DNA Phenotyping (FDP), has started to become established in forensic biology. We previously developed and forensically validated the IrisPlex system for accurate prediction of blue and brown eye colour from DNA, and recently showed that all major hair colour categories are predictable from carefully selected DNA markers. Here, we introduce the newly developed HIrisPlex system, which is capable of simultaneously predicting both hair and eye colour from DNA. HIrisPlex consists of a single multiplex assay targeting 24 eye and hair colour predictive DNA variants including all 6 IrisPlex SNPs, as well as two prediction models, a newly developed model for hair colour categories and shade, and the previously developed IrisPlex model for eye colour. The HIrisPlex assay was designed to cope with low amounts of template DNA, as well as degraded DNA, and preliminary sensitivity testing revealed full DNA profiles down to 63 pg input DNA. The power of the HIrisPlex system to predict hair colour was assessed in 1551 individuals from three different parts of Europe showing different hair colour frequencies. Using a 20% subset of individuals, while 80% were used for model building, the individual-based prediction accuracies employing a prediction-guided approach were 69.5% for blond, 78.5% for brown, 80% for red and 87.5% for black hair colour on average. Results from HIrisPlex analysis on worldwide DNA samples imply that HIrisPlex hair colour prediction is reliable independent of bio-geographic ancestry (similar to previous IrisPlex findings for eye colour). We furthermore demonstrate that it is possible to infer with a prediction accuracy of >86% if a brown-eyed, black-haired individual is of non-European (excluding regions nearby Europe) versus European (including nearby regions) bio-geographic origin solely from the strength of HIrisPlex eye and hair colour probabilities, which can provide extra intelligence for future forensic applications. The HIrisPlex system introduced here, including a single multiplex test assay, an interactive tool and prediction guide, and recommendations for reporting final outcomes, represents the first tool for simultaneously establishing categorical eye and hair colour of a person from DNA. The practical forensic application of the HIrisPlex system is expected to benefit cases where other avenues of investigation, including STR profiling, provide no leads on who the unknown crime scene sample donor or the unknown missing person might be.

Inferring ancestral origin using a single multiplex assay of ancestry-informative marker SNPs.

Abstract: Tests that infer the ancestral origin of a DNA sample have considerable potential in the development of forensic tools that can help to guide crime investigation. We have developed a single-tube 34-plex SNP assay for the assignment of ancestral origin by choosing ancestry-informative markers (AIMs) exhibiting highly contrasting allele frequency distributions between the three major population-groups. To predict ancestral origin from the profiles obtained, a classification algorithm was developed based on maximum likelihood. Sampling of two populations each from African, European and East Asian groups provided training sets for the algorithm and this was tested using the CEPH Human Genome Diversity Panel. We detected negligible theoretical and practical error for assignments to one of the three groups analyzed with consistently high classification probabilities, even when using reduced subsets of SNPs. This study shows that by choosing SNPs exhibiting marked allele frequency differences between population-groups a practical forensic test for assigning the most likely ancestry can be achieved from a single multiplexed assay.

EMPOP—A forensic mtDNA database

Abstract: Mitochondrial DNA databases stand as the basis for frequency estimations of mtDNA sequences that became relevant in a case. The establishment of mtDNA databases sounds trivial; however, it has been shown in the past that this undertaking is prone to error for several reasons, particularly human error. We have established a concept for mtDNA data generation, analysis, transfer and quality control that meets forensic standards. Due to the complexity of mtDNA population data tables it is often difficult if not impossible to detect errors, especially for the untrained eye. We developed software based on quasi-median network analysis that visualizes mtDNA data tables and thus signposts sequencing, interpretation and transcription errors. The mtDNA data (N=5173; release 1) are stored and made publicly available via the Internet in the form of the EDNAP mtDNA Population Database, short EMPOP. This website also facilitates quasi-median network analysis and provides results that can be used to check the quality of mtDNA sequence data. EMPOP has been launched on 16 October 2006 and is since then available at http://www.empop.org.

Next generation sequencing and its applications in forensic genetics

Abstract: It has been almost a decade since the first next generation sequencing (NGS) technologies emerged and quickly changed the way genetic research is conducted. Today, full genomes are mapped and published almost weekly and with ever increasing speed and decreasing costs. NGS methods and platforms have matured during the last 10 years, and the quality of the sequences has reached a level where NGS is used in clinical diagnostics of humans. Forensic genetic laboratories have also explored NGS technologies and especially in the last year, there has been a small explosion in the number of scientific articles and presentations at conferences with forensic aspects of NGS. These contributions have demonstrated that NGS offers new possibilities for forensic genetic case work. More information may be obtained from unique samples in a single experiment by analyzing combinations of markers (STRs, SNPs, insertion/deletions, mRNA) that cannot be analyzed simultaneously with the standard PCR-CE methods used today. The true variation in core forensic STR loci has been uncovered, and previously unknown STR alleles have been discovered. The detailed sequence information may aid mixture interpretation and will increase the statistical weight of the evidence. In this review, we will give an introduction to NGS and single-molecule sequencing, and we will discuss the possible applications of NGS in forensic genetics.