SciCombinator

Discover the most talked about and latest scientific content & concepts.

Journal: Investigative genetics

194

BACKGROUND: DNA analysis of ancient skeletal remains is invaluable in evolutionary biology for exploring the history of species, including humans. Contemporary human bones and teeth, however, are relevant in forensic DNA analyses that deal with the identification of perpetrators, missing persons, disaster victims or family relationships. They may also provide useful information towards unravelling controversies that surround famous historical individuals. Retrieving information about a deceased person’s externally visible characteristics can be informative in both types of DNA analyses. Recently, we demonstrated that human eye and hair colour can be reliably predicted from DNA using the HIrisPlex system. Here we test the feasibility of the novel HIrisPlex system at establishing eye and hair colour of deceased individuals from skeletal remains of various post-mortem time ranges and storage conditions. METHODS: Twenty-one teeth between 1 and approximately 800 years of age and 5 contemporary bones were subjected to DNA extraction using standard organic protocol followed by analysis using the HIrisPlex system. RESULTS: Twenty-three out of 26 bone DNA extracts yielded the full 24 SNP HIrisPlex profile, therefore successfully allowing model-based eye and hair colour prediction. HIrisPlex analysis of a tooth from the Polish general W[latin small letter l with stroke]adys[latin small letter l with stroke]aw Sikorski (1881 to 1943) revealed blue eye colour and blond hair colour, which was positively verified from reliable documentation. The partial profiles collected in the remaining three cases (two contemporary samples and a 14th century sample) were sufficient for eye colour prediction. CONCLUSIONS: Overall, we demonstrate that the HIrisPlex system is suitable, sufficiently sensitive and robust to successfully predict eye and hair colour from ancient and contemporary skeletal remains. Our findings, therefore, highlight the HIrisPlex system as a promising tool in future routine forensic casework involving skeletal remains, including ancient DNA studies, for the prediction of eye and hair colour of deceased individuals.

Concepts: DNA, Molecular biology, Full genome sequencing, Identification, Eye color, DNA profiling, National DNA database, Combined DNA Index System

160

Anthropological and genetic data agree in indicating the African continent as the main place of origin for anatomically modern humans. However, it is unclear whether early modern humans left Africa through a single, major process, dispersing simultaneously over Asia and Europe, or in two main waves, first through the Arab Peninsula into southern Asia and Oceania, and later through a northern route crossing the Levant.

Concepts: Human, Africa, Asia, Human evolution, Prehistory, Archaic Homo sapiens, Humans, Homo sapiens idaltu

151

Whole-genome sequencing is performed routinely as a means to identify polymorphic genetic loci such as short tandem repeat loci. We have developed a simple tool, called pSTR Finder, which is freely available as a means of identifying putative polymorphic short tandem repeat (STR) loci from data generated from genome-wide sequences. The program performs cross comparisons on the STR sequences generated using the Tandem Repeats Finder based on multiple-genome samples in a FASTA format. These comparisons generate reports listing identical, polymorphic, and different STR loci when comparing two samples.

Concepts: Bioinformatics, Sequence, Identification, Variable number tandem repeat, Short tandem repeat, Repetitive DNA sequences, Tandem repeat, Repeat sign

19

The generation of short tandem repeat profiles, also referred to as ‘DNA typing,’ is not currently performed outside the laboratory because the process requires highly skilled technical operators and a controlled laboratory environment and infrastructure with several specialized instruments. The goal of this work was to develop a fully integrated system for the automated generation of short tandem repeat profiles from buccal swab samples, to improve forensic laboratory process flow as well as to enable short tandem repeat profile generation to be performed in police stations and in field-forward military, intelligence, and homeland security settings.

Concepts: DNA, Motivation, Variable number tandem repeat, Short tandem repeat, Profiles, Tandem repeat, Infrastructure security

18

Short tandem repeat (STR) analysis of casework samples with low DNA content include those resulting from the transfer of epithelial cells from the skin to an object (e.g., cells on a water bottle, or brim of a cap), blood spatter stains, and small bone and tissue fragments. Low DNA content (LDC) samples are important in a wide range of settings, including disaster response teams to assist in victim identification and family reunification, military operations to identify friend or foe, criminal forensics to identify suspects and exonerate the innocent, and medical examiner and coroner offices to identify missing persons. Processing LDC samples requires experienced laboratory personnel, isolated workstations, and sophisticated equipment, requires transport time, and involves complex procedures. We present a rapid DNA analysis system designed specifically to generate STR profiles from LDC samples in field-forward settings by non-technical operators. By performing STR in the field, close to the site of collection, rapid DNA analysis has the potential to increase throughput and to provide actionable information in real time.

Concepts: DNA, Blood, Epithelium, Skin, Connective tissue, Identification, Short tandem repeat, Bloodstain pattern analysis

18

Patterns of genetic variation in a population carry information about the prehistory of the population, and for the human Y chromosome an especially informative phylogenetic tree has previously been constructed from fully-sequenced chromosomes. This revealed contrasting bifurcating and starlike phylogenies for the major lineages associated with the Neolithic expansions in sub-Saharan Africa and Western Europe, respectively.

Concepts: DNA, Human, Evolution, Biology, Africa, Species, Chromosome, Europe

18

DNA fingerprinting, one of the great discoveries of the late 20th century, has revolutionized forensic investigations. This review briefly recapitulates 30 years of progress in forensic DNA analysis which helps to convict criminals, exonerate the wrongly accused, and identify victims of crime, disasters, and war. Current standard methods based on short tandem repeats (STRs) as well as lineage markers (Y chromosome, mitochondrial DNA) are covered and applications are illustrated by casework examples. Benefits and risks of expanding forensic DNA databases are discussed and we ask what the future holds for forensic DNA fingerprinting.

Concepts: DNA, Full genome sequencing, Identification, DNA profiling, National DNA database, Combined DNA Index System, Alec Jeffreys

16

The archeological record indicates that the permanent settlement of Cyprus began with pioneering agriculturalists circa 11,000 years before present, (ca. 11,000 y BP). Subsequent colonization events followed, some recognized regionally. Here, we assess the Y-chromosome structure of Cyprus in context to regional populations and correlate it to phases of prehistoric colonization.

Concepts: Population, Copper, Neolithic, Archaeology, Prehistory, Bronze Age, Synoptic table of the principal old world prehistoric cultures, Three-age system

14

In this interview we talk with Professor Sir Alec Jeffreys about DNA fingerprinting, his wider scientific career, and the past, present and future of forensic DNA applications.The podcast with excerpts from this interview is available at: http://www.biomedcentral.com/biome/alec-jeffreys.

Concepts: DNA, Full genome sequencing, DNA profiling, National DNA database, Combined DNA Index System, Alec Jeffreys, Colin Pitchfork

13

Wildlife collisions with aircraft cost the airline industry billions of dollars per annum and represent a public safety risk. Clearly, adapting aerodrome habitats to become less attractive to hazardous wildlife will reduce the incidence of collisions. Formulating effective habitat management strategies relies on accurate species identification of high-risk species. This can be successfully achieved for all strikes either through morphology and/or DNA-based identifications. Beyond species identification, dietary analysis of birdstrike gut contents can provide valuable intelligence for airport hazard management practices in regards to what food is attracting which species to aerodromes. Here, we present birdstrike identification and dietary data from Perth Airport, Western Australia, an aerodrome that saw approximately 140,000 aircraft movements in 2012. Next-generation high throughput DNA sequencing was employed to investigate 77 carcasses from 16 bird species collected over a 12-month period. Five DNA markers, which broadly characterize vertebrates, invertebrates and plants, were used to target three animal mitochondrial genes (12S rRNA, 16S rRNA, and COI) and a plastid gene (trnL) from DNA extracted from birdstrike carcass gastrointestinal tracts.

Concepts: DNA, Gene, RNA, Species, Ribosomal RNA, Bird, Airport, Airline