Dec 18 2017
Top 10 Blog Posts of 2017
As 2017 winds down, let’s celebrate all that’s happened in the world of ISHI this year! We converged on Seattle, Washington for the 28th annual International Symposium on Human Identification where we discussed new technologies, probabilistic genotyping, massively parallel sequencing, and testifying as an expert witness. We also heard Michael Capuzzo present on the mysterious Vidocq Society.
Many of you also contributed stories to the ISHI blog this year! Scroll below to read the top ten posts from 2017 and subscribe to the blog at the end of the post to have future ISHI posts delivered to your email! We look forward to continuing to share actionable tips, new technologies, and announcements with you in 2018!
History of DNA
- From the discovery of the PCR process in 1983 to the publishing of ISO 18385 and the expansion of the core loci, we put together a timeline of DNA throughout the years to celebrate DNA Day.
Rapid DNA Act of 2017: What is It?
- On May 16, 2017, the U.S House of Representatives and the U.S. Senate passed the Rapid DNA Act of 2017 (H.R.510 and S.139, respectively). The bill was sponsored by Senator Orrin Hatch (R-UT) and Representative James Sensenbrenner (R-Wis) and enjoyed bipartisan support, ending up with seven Republican and five Democratic cosponsors in the Senate, and seventeen Republican and seven Democratic cosponsors in the House. The bill was passed by unanimous consent voice votes in both chambers, but what exactly does it entail?
Courtroom Testimony for Probabilistic Genotyping
- Most individuals working in the legal system are now familiar with the Random Match Probability statistic. They understand that we can explain how rare a DNA profile is within the population, often wanting to hear how many planet Earths it would take to expect to see that profile. However, this comparison is not an appropriate analogy when you are reporting a Likelihood Ratio (LR). With the advent of probabilistic genotyping software, the challenge arises with not only how to present the “new” statistic, but how to explain probabilistic genotyping in general.
Forensic Genetic Genealogy… How does it work?
- We spoke with Colleen Fitzpatrick, an internationally recognized forensic genealogist to learn more about the process of genetic genealogy, and how it can be used to help solve future cases.
New Perspectives at ISHI
- Those who attend the International Symposium on Human Identification (ISHI) know that the annual meeting bringing together the world’s top forensic DNA analysts, law enforcement, and legal and ethical experts offers unique opportunities for new perspectives on old cases. For Phoenix Police Department detectives, the novel approach provided by genetic genealogist Colleen Fitzpatrick, whom they met at ISHI two years ago, led to what became the big break in an almost 25-year hunt for a serial murderer dubbed the “Canal Killer.”
The Use of Methylation Markers for Age Estimation of an Unknown Individual Based on Biological Traces
- According to public data form e.g. UK database around 30% of DNA profiles generated do not return a match from a database search. In many countries the percentage is much higher. In such cases additional phenotype data which could be derived from the genomic sequences are helpful in investigators profiling. Recently it has become feasible to obtain information about the age of the person from whom the genetic material was originating.This technology is based on the observation that the epigenetic markers, namely methylation level of selected CpG loci in human genomes, correlated with the human age.
Accuracy and Reliability of Ancestry Predictions from the Precision ID Ancestry Panel
- As single nucleotide polymorphism (SNP) analysis by massively parallel sequencing (MPS) becomes increasingly prominent, research on commercially-available panels is essential prior to implementation. SNPs can be used as supplementary information to existing STR profiles, thus giving investigators more information to work with.
- For this study, we focused on evaluating the genotype reproducibility, sensitivity, and performance of the Precision ID Ancestry Panel on the Ion Torrent™ PGM™ Sequencer with high-quality samples (9948, HeLa, etc.) and forensic-type samples (toothbrush, hair, cigarette butt, chewing gum, etc.). We also looked at the ability to use FROG-kb, a SNP reference/resource tool, to determine genotype reliability from samples of various simulated degradation levels. Traditional extraction and quantitation procedures were used prior to library preparation for MPS processing.
Real-World Tips on How to Excel as an Expert Witness
- In part one of our series on being an expert witness (Demystifying the Thoughts of Juror During Expert Witness Testimony), we examined what jury members were thinking during testimony. This week, we will discuss actionable tips you can use the next time you are called to the witness stand.
A Chance Reunion at ISHI
- It played out in front of a packed hotel ballroom of some 800 people at last year’s International Symposium on Human Identification (ISHI) in Minneapolis: the unexpected reunion between the survivor of a brutal serial rapist and the forensic analyst who found the DNA that led to a conviction in the case.
An Introduction to Mindfulness
- On Sunday, October 1st, ISHI will be offering it’s first workshop focused on mindfulness lead by Amy Jeanguenat. Though the concept of mindfulness has been gaining popularity in recent years, some of you may not yet be familiar with the term, so we’ve asked Amy to define mindfulness and its many benefits.