PubMed Health⌕ Search

Biomedical subjects

Niels Morling

Publications and source records attributed to Niels Morling.

9 recordsLinked to original sources
PubMed2026

Precision ID mtDNA Whole Genome Panel and sequencing of telogen hairs - perspectives for validation and implementation in casework.

Shed hair is a commonly encountered type of forensic evidence. Shed telogen hairs generally contain insufficient or highly degraded nuclear DNA for STR profiling; however, mtDNA analysis of telogen hair and hair shafts remains possible. We validated whole mitochondrial genome (mtGenome) sequencing using the Precision ID mtDNA Whole Genome Panel (Thermo Fisher Scientific) and subsequently implemented the panel for the analysis of telogen hair, buccal, and casework samples. We analysed 90 diluted DNA samples containing 3-3,600 mtDNA copies, shed telogen hairs and their corresponding mtDNA from buccal swabs from 91 individuals, and 11 archived DNA extracts from hair samples in criminal cases. Complete mtGenome sequences were consistently recovered in 99% of samples across DNA dilution series at DNA input levels as low as 47 mtDNA copies, demonstrating the assay's robustness under low-template conditions. We obtained complete and reproducible mtGenome sequences with ≥ 327 mtDNA copies/µL from telogen hair samples. After applying ISFG recommendations and excluding low-confidence discrepancies associated with high-strand bias, heteroplasmic variants and sequencing artifacts, mtGenome sequence concordance increased from 93.4% to 100%. None of the 16 negative controls produced complete mtDNA sequences. Six negative controls showed low-level mtDNA signal (2-8 variants), consisting predominantly of common polymorphisms. These samples did not yield complete mtGenome sequences and showed no correspondence to any of the analysed samples. Finally, archived telogen hair samples from criminal cases presented complete mtGenome sequences with an average read depth of 1,037x.Our findings highlight the reliability of mtDNA analysis of telogen hairs using the Precision ID mtDNA Whole Genome Panel for implementation in forensic casework.

Forensic casework↗
PubMed2003

Application of thiopropyl sepharose 6B for removal of PCR inhibitors from DNA extracts of a thigh bone recovered from the sea.

PCR amplification of DNA from forensic samples often proves difficult due to the presence of inhibitors of the polymerase chain reaction. One possible way to remove PCR inhibitors from a DNA extract is the use of the affinity resin thiopropyl sepharose 6B (TS), which has been used previously for the removal of PCR inhibitors in DNA extracts originating from stains on clothing. Here we show that TS is efficient also for the removal of inhibitors from PCR extracts from a highly decomposed human thigh bone. TS treatment, however, leads to a substantial loss of DNA making the technique best suited when substantial amounts of DNA are present.

DNA↗
PubMed2003

[Forensic genetics].

The review first summarizes the molecular biology methods used in forensic genetics in Denmark. In criminal cases, there is international consensus about investigation of Short Tandem Repeat (STR)-regions with polymerase chain reaction (PCR)based methods that are standardised through international collaboration. In paternity and immigration cases, investigations are performed of both STR-regions with PCR-based methods and of variable number of tandem repeat (VNTR)-regions with restriction fragment length polymorphism (RFLP)-technique. Thereafter some of the most promising areas of research and development in forensic genetics are described, including investigations of still smaller amounts of DNA from biological traces, single nucleotide polymorphism (SNP) used for identification, identification of factors that can contribute to information about physical traits, and farmacogenetic investigations.

Base Sequence↗
PubMed2002

Paternity Testing Commission of the International Society of Forensic Genetics: recommendations on genetic investigations in paternity cases.

The International Society for Forensic Genetics (ISFG) has established a Paternity Testing Commission (PTC) with the purpose of formulating international recommendations concerning genetic investigations in paternity testing. The PTC recommends that paternity testing be performed in accordance with the ISO 17025 standards. The ISO 17025 standards are general standards for testing laboratories and the PTC offers explanations and recommendations concerning selected areas of special importance to paternity testing.

Equipment and Supplies↗
PubMed2002

A report of the 2000 and 2001 paternity testing workshops of the English speaking working group of the international society for forensic genetics.

During the last 10 years, the English Speaking Working Group (ESWG) of the International Society for Forensic Genetics (ISFG) has once a year arranged a Paternity Testing Workshop in which blood samples as well as a questionnaire concerning laboratory strategies were distributed to the participating laboratories. In 2000 and 2001, paper challenges were included in the workshops. Here, we present the results of the 2000 and 2001 Paternity Testing Workshops. The numbers of participating laboratories were 33 (2000) and 36 (2001). A total of 36% (2000) and 31% (2001) of the laboratories submitted typing results of variable number of tandem repeats (VNTRs) investigated with restriction fragment length polymorphism (RFLP) and single locus probes (SLPs). A total of 91% (2000) and 86% (2001) submitted typing results of polymerase chain reaction (PCR) based systems. Typing errors occurred in 0.3% of the submitted PCR-based results in 2000 and in 0.1% in 2001. The results of the paper challenges showed a high degree of variation in the formulas used for calculation of the weight of evidence of rare events such as inconsistencies or possible silent alleles. The majority of the laboratories used the same formulas for calculations of frequently occurring events.

Alleles↗
PubMed2002

Plasma vitamin D-binding protein (GC) factors, immunoglobulin G heavy chain (GM) allotypes and immunoglobulin kappa light chain (KM1) allotype in patients with sarcoidosis and in healthy control subjects.

BACKGROUND AND AIM: Sarcoidosis is an immune disease with abnormalities in the production of vitamin D and immunoglobulins. The aim was to examine whether the distribution of plasma vitamin D-binding protein = group-specific component (GC) allotypes, immunoglobulin G heavy chain (GM) allotypes and immunoglobulin kappa light chain (KM) allotype differed significantly from the distribution in healthy subjects. METHODS: GC 1S, 1F, 2 allotypes, GM 1, 2, 5 allotypes, and KM1 allotype were assessed in 44 patients with sarcoidosis and in healthy control subjects. RESULTS: There were no significant differences between the frequencies of the GC, GM and KM allotypes in sarcoidosis patients and in control subjects. Furthermore, there was no relationship between the presentation or course of the sarcoid disease and GC, GM or KM allotypes. CONCLUSIONS: GC, GM and KMI allotypes do not appear to play any major role in the pathogenesis of sarcoidosis.

Adult↗