Identifying Novel Types of Forensic Markers in Degraded DNA
News Jun 24, 2016
In the case of mass disasters, missing persons and forensic caseworks, highly degraded biological samples are often encountered. It can be a challenge to analyze and interpret the DNA profiles from these samples. Here we provide a new strategy to solve the problem by taking advantage of the intrinsic structural properties of DNA. We have assessed the in vivo positions of more than 35 million putative nucleosome cores in human leukocytes using high-throughput whole genome sequencing, and identified 2,462 single nucleotide variations (SNVs), 128 insertion-deletion polymorphisms (indels). After comparing the sequence reads with 44 STR loci commonly used in forensics, five STRs (TH01, TPOX, D18S51, DYS391, and D10S1248)were matched. We compared these "nucleosome protected STRs" (NPSTRs) with five other non-NPSTRs using mini-STR primer design, real-time PCR, and capillary gel electrophoresis on artificially degraded DNA. Moreover, genotyping performance of the five NPSTRs and five non-NPSTRs was also tested with real casework samples. All results show that loci located in nucleosomes are more likely to be successfully genotyped in degraded samples. In conclusion, after further strict validation, these markers could be incorporated into future forensic and paleontology identification kits, resulting in higher discriminatory power for certain degraded sample types.
The full article is available on the further information link below.
Scientists Decry Lack of Science in ‘Forensic Science’News
Many of the “forensic science” methods commonly used in criminal cases and portrayed in popular police TV dramas have never been scientifically validated and may lead to unjust verdicts, according to a recent article.
Drug Prevalence Means that Even Many Non-Users Have Them on Their FingerprintsNews
Scientists have found that drugs are now so prevalent that 13 per cent of those taking part in a test were found to have traces of class A drugs on their fingerprints - despite never using them.READ MORE
Robotics Takes Mass Spec to the Third DimensionNews
Within the past decade, many advancements have been made in the 3-D market from printing to movies. Now scientists report that by combining a robotic arm and mass spectrometry, they can analyze the surface of irregularly shaped 3-D objects, potentially opening up new branches of forensics and pharmaceutics.READ MORE