ABSTRACT
The European Forensic Genetics Network of Excellence (EUROFORGEN-NoE) undertook a collaborative project on mRNA-based body fluid/skin typing and the interpretation of the resulting RNA and DNA data. Although both body fluids and skin are composed of a variety of cell types with different functions and gene expression profiles, we refer to the procedure as 'cell type inference'. Nine laboratories participated in the project and used a 20-marker multiplex to analyse samples that were centrally prepared and thoroughly tested prior to shipment. Specimens of increasing complexity were assessed that ranged from reference PCR products, cDNAs of indicated or unnamed cell type source(s), to challenging mock casework stains. From this specimen set, information on the overall sensitivity and specificity of the various markers was obtained. In addition, the reliability of a scoring system for inference of cell types was assessed. This scoring system builds on replicate RNA analyses and the ratio observed/possible peaks for each cell type [1]. The results of the exercise support the usefulness of this scoring system. When interpreting the data obtained from the analysis of the mock casework stains, the participating laboratories were asked to integrate the DNA and RNA results and associate donor and cell type where possible. A large variation for the integrated interpretations of the DNA and RNA data was obtained including correct interpretations. We infer that with expertise in analysing RNA profiles, clear guidelines for data interpretation and awareness regarding potential pitfalls in associating donors and cell types, mRNA-based cell type inference can be implemented for forensic casework.
Subject(s)
Body Fluids/metabolism , Cooperative Behavior , DNA/genetics , RNA, Messenger/genetics , Skin/metabolism , Base Sequence , DNA Primers , Europe , Humans , Polymerase Chain ReactionABSTRACT
In mass fatality incidents, for example following a vehicle accident or terrorist event, severe fragmentation of bodies may occur, making identification by the use of traditional techniques such as fingerprinting or odontology difficult. In such situations DNA profiling can be employed for individualization and re-association of fragmented remains. As at times disrupted soft tissue may be the predominate tissue type requiring identification and re-association. We have investigated the use of two buffer solutions for preservation of soft tissue samples that may be collected during such investigations, when buccal cells, blood samples or teeth or bone may not be available. Both buffer solutions have shown sufficient DNA preservation over a 12-month period of storage at room temperature to allow for DNA profiling to be successfully performed when 5-1000 mg muscle tissue was stored in each solution.
Subject(s)
DNA/isolation & purification , Disasters , Preservation, Biological/methods , Research Personnel , Temperature , Buffers , DNA/analysis , DNA Fingerprinting/methods , Fixatives/chemistry , Humans , Musculoskeletal System/chemistry , Solutions/chemistry , Specimen Handling , Time FactorsABSTRACT
Approximately 21% of children suffer from some form of physical abuse. It is hypothesized that when an individual hits a child some of that person's DNA will be deposited onto the child's skin. As yet, no one has reported a method of sampling DNA from the skin of this vulnerable group of individuals. We have sampled DNA from several facial areas of 30 children aged 5 years of age and under. The results show that it is possible to swab the faces of this age group without distressing them or contaminating the samples. Additionally the results indicate that the DNA obtained is almost entirely that of the subject, with little nondonor DNA being observed.
Subject(s)
Child Abuse/diagnosis , DNA Fingerprinting/methods , Face , Forensic Nursing/methods , Specimen Handling/methods , Cephalometry , Child , Child Abuse/psychology , Child Abuse/statistics & numerical data , Child, Preschool , Feasibility Studies , Female , Humans , Infant , Infant, Newborn , Male , Nursing Assessment , Nursing Evaluation Research , Patient Acceptance of Health Care , Polymerase Chain Reaction/methods , Psychology, Child , Risk Factors , Specimen Handling/instrumentation , Specimen Handling/nursing , Specimen Handling/psychologyABSTRACT
The question of whether blood transfusions can affect DNA profiling is still a contentious issue throughout the forensic community. It is hypothesised that donor leucocytes present in the administered blood will be detected upon examination of recipient blood. In order to resolve this issue, a selection of theoretical experiments were carried out to determine how much donor DNA must be present for its detection in blood components. Five casework examples of material collected from individuals after massive transfusion, including a case of whole organ transplantation, were also investigated. The results indicated that filtration processes used during blood production do not allow the passage of enough donor leucocytes for detection using current forensic profiling techniques. No evidence of secondary profile alleles were found in any case, indicating that peri-mortem blood transfusion does not affect DNA profiling.
Subject(s)
Autopsy/methods , Blood Transfusion , DNA Fingerprinting/methods , DNA/blood , Microsatellite Repeats/genetics , HumansABSTRACT
DNA profiling of biological trace evidence has been used for many years. The application of this technique specifically to the DNA profiling of earprints has not to date been thoroughly investigated. This report presents the results of 60 earprints collected from three healthy adult volunteers under controlled laboratory conditions. DNA profile analysis revealed that high levels of non-donor alleles are observed when earprints are collected for DNA profiling. The source of these non-donor alleles is investigated and the impact that their presence within the profile may have on the use of this technique is discussed.
Subject(s)
DNA Fingerprinting , Ear, External , Forensic Sciences/methods , Adult , Alleles , Humans , Nucleic Acid Amplification Techniques , Reproducibility of Results , Specimen HandlingABSTRACT
Human and nonhuman hairs are often recovered during forensic investigation. As with all other biological samples that may be collected, via DNA analysis, hairs have the potential to provide the investigating authority with valuable intelligence pertaining to the identity of offenders, victims and even pets. DNA analysis of hairs is not however a straightforward process. The biochemical make up of hairs provide the DNA analyst with a unique set of challenges that must be overcome before any useful information can be gleaned from the evidence. This short review provides an overview of the location and condition of DNA within hair samples, and discusses the analytical methods that are employed to maximise the information that can be obtained from this sample type.
ABSTRACT
The rapid development, success, and occasional failures of forensic DNA profiling are highly publicised, and as a consequence are well known to the scientific and public communities alike. Over the same period of time that forensic DNA typing has accelerated onto the scene, another related discipline has been born and has made equally, or perhaps, even more groundbreaking achievements in the same arena; that is the science of (bio)molecular archaeology. This review describes the extreme complications of ancient DNA analysis and highlights some of the major achievements that have been accomplished in this field. The nature of DNA degradation and possible solutions to this problem are discussed.
ABSTRACT
The national DNA database in United Kingdom has now been operational for over 10 years. This review looks at the history and development of this investigative resource. From the development of commercial DNA profiling kits to the current statistics for matches obtained in relation to criminal investigation in the United Kingdom, before moving onto discussing potential future direction that national DNA databases might take, including international collaboration on a European and global scale.
Subject(s)
Criminals , DNA Fingerprinting , Databases, Genetic , Genetic Markers , Amplified Fragment Length Polymorphism Analysis , DNA Fingerprinting/history , DNA Fingerprinting/trends , Databases, Genetic/history , Databases, Genetic/trends , Diffusion of Innovation , Forecasting , History, 21st Century , Humans , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Time Factors , United KingdomABSTRACT
In 1923, within the Manual of Police technique, Edmond Locard published what is commonly known as the Doctrine of Exchange; a series of rules related to the exchange of trace evidence between the victim and offender. Although at the time of publication these rules principally applied to trace evidence related to print (for exchange finger print or shoeprint), fibre and blood, today one can add the very substance that defines each human being -- DNA. Since th first use of DNA evidence to help identify an offender in the Pitchfork Murders of 1986, the use of DNA within forensic science has developed from its humble days within a single experimental laboratory at the University of Leicester to a multi-million pound industry. It thus seams fitting that this forensic web watch should originate from the very University where the use of DNA in forensic science was conceived, drawing the readers attention to a number of sites which can be used as an introduction to the concept of the use of DNA in forensic science today.
