The 33rd International Symposium on Human Identification: The Past, Present and Future of Investigative Genetic Genealogy

It’s hard to imagine a better way to celebrate the 33rd International Symposium of Human Identification than a night spent wandering through the Hall of Human Evolution at the Smithsonian Museum of Natural History. The meeting, which took place in Washington D.C. from October 31–November 4, focused largely on using investigative genetic genealogy (IGG). When used to identify human remains or solve cold cases, IGG (a.k.a. forensic genetic genealogy or forensic investigative genetic genealogy, take your pick) relies heavily on techniques developed to sequence DNA from ancient human remains.

A crowd dances in a stone courtyard with a taxidermy elephant on display.
Credit: ISHI

New to ISHI this year were live-streamed presentations, building off the success of last year’s session recordings for online streaming. Another first was attendees dressing up in costume for the welcome reception, which happened to coincide with Halloween. From a nucleic acid-themed group costume to Sims characters to a bunch of grapes, ISHI 33 attendees had a chance to show off their fun side while reconnecting with colleagues.

While a range of topics were covered during the workshops, sessions and poster presentations, three themes stood out to this first-time ISHI attendee. In addition to IGG, there was widespread interest in developments in DNA databases as well as efforts to mobilize DNA analysis labs.

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Neanderthal DNA and Modern Humans: Svante Pääbo Receives the 2022 Nobel Prize in Physiology or Medicine

What makes humans “human”?

Neanderthal DNA sequencing from ancient bone samples

On October 3, 2022, the Nobel Assembly at Karolinska Institutet announced the 2022 Nobel Prize in Physiology or Medicine had been awarded to Svante Pääbo, director of the Department of Genetics at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. The Assembly cited his “discoveries concerning the genomes of extinct hominins and human evolution”. They mentioned the highlight of his research: the seemingly impossible task, at the time, of sequencing the Neanderthal genome. The discoveries that followed from this sequencing project continue to redefine our understanding of modern human origins.

The award showcases the technological advancements made in the analysis of ancient DNA. However, Pääbo’s research had an inauspicious beginning. In 1985, he published the results of his early work, cloning and sequencing DNA fragments from a 2,400-year-old Egyptian mummy (1). Unfortunately, later analysis revealed that the samples could have been contaminated by the researchers’ own DNA (2).

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Bones: Improved Technology is Bringing Loved Ones Home

21537407 - archeology, human bones

Today’s Promega Connections blog is written by guest blogger Rachel H. Oefelein, QA Manager/Senior DNA Analyst at DNA Labs International. 

Shakespeare said, “The evil that men do lives after them; the good is oft interred with their bones.”  This is continually true in the case of unidentified remains throughout the United States.  The action of a person going missing or the events leading to an individual’s demise are frequently the memory that haunts a town or the media for years to come. However, for each such case, somewhere lies a set of skeletal remains not yet found, or just as tragic, recovered but still unidentified.  The National Missing and Unidentified Persons System (NamUs) estimates approximately 40,000 sets of unidentified skeletal remains linger in morgues around the country or that have been cremated and buried as Jane and John Does.

Many crime labs do not have protocols in place for the extraction of DNA from skeletal remains or have outdated protocols for bone extraction that are not sensitive enough for poor quality bones. Bones are often recovered from harsh environments and have been exposed to extreme heat, time, acidic soil, swamp, chemicals treatment, etc. These harsh environmental conditions degrade the DNA present in the remains which further complicates the already difficult procedure of releasing the DNA in cells buried deep within the bone matrix. Another challenge is that cases often involve recovery of skeletal remains in areas with animal activity, water recoveries and scenes involving explosions or fires; these case types may require re-association of dozens if not hundreds of bones and bone fragments.

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Ten Validation Tips You Need to Know

example

Forensic lab validations can be intimidating, so Promega Technical Services Support and Validation teams shared these tips for making the process go more smoothly.

  1.  Prepare Your Lab. Make sure all of your all of your instrumentation (CEs, thermal cyclers, 7500s, centrifuges) and tools (pipettes, heat blocks) requiring calibration or maintenance are up to date.
  2.  Start with Fresh Reagents. Ensure you have all required reagents and that they are fresh before beginning your validation. This not only includes the chemistry being validated, but any preprocessing reagents or secondary reagents like, polymer, buffers, TE-4 or H2O.
  3. Develop a Plan. Before beginning a validation, take the time to create plate maps, calculate required reagent volumes, etc. This up-front planning may take some time initially, but will greatly improve your efficiency during testing.
  4. Create an Agenda. After a plan is developed, work through that plan and determine how and when samples will be created and run. Creating an agenda will hold you to a schedule for getting the testing done.
  5. Determine the Number of Samples Needed to Complete Your Validation. Look at your plan and see where samples can be used more than once.  The more a sample can be used, the less manipulation done to the sample and the more efficient you become.
  6. Select the Proper Samples for Your Validation. Samples should include those you know you’ll obtain results with be similar to the ones you’ll most likely be using, and your test samples should contain plenty of heterozygotes. When you are establishing important analysis parameters, like thresholds, poor sample choice may cause more problems and require troubleshooting after the chemistry is brought on-line.
  7. Perform a Fresh Quantitation of Your Samples. This will ensure the correct dilutions are prepared. Extracts that have been sitting for a long time may have evaporated or contain condensation, resulting in a different concentration than when first quantitated.
  8. Stay Organized. Keep the data generated in well-organized folders. Validations can contain a lot of samples, and keeping those data organized will help during the interpretation and report writing phase.
  9. Determine the Questions to Be Answered. While writing the report, determine the questions each study requires to be answered. Determining what specifically is required for each study will prevent you from calculating unnecessary data.  Do you need to calculate allele sizes of your reproducibility study samples when you showed precision with your ladder samples?
  10. Have fun! Remember, validations are not scary when approached in a methodical and logical fashion. You have been chosen to thoroughly test something that everyone in your laboratory will soon be using. Take pride in that responsibility and enjoy it.

Need more information about validation of DNA-typing products in the forensic laboratory? Check out the validation resources on the Promega web site for more information for the steps required to adopt a new product in your laboratory and the recommended steps that can help make your validation efforts less burdensome.

Rapid DNA Technology: Establishing your Identity in Less than Two Hours

DNA SequenceWhile the forensic and general communities continue to argue about the merits of the recent Supreme Court ruling on collection of samples from arrestees prior to conviction, I am fascinated by the technology that make this question relevant. The conventional way of generating a DNA profile from a sample by STR (short tandem repeat) analysis is a long process involving a series of steps that require sophisticated expensive equipment, trained personnel and, more importantly, time. The actual process of DNA analysis consists of a) sample collection, b) DNA extraction, c) PCR amplification using 16 or more unique fluorescently labeled primer sets d) capillary electrophoresis to size labeled DNA amplicons, e) software analysis to size DNA fragments and allele calls based on migration of allelic ladder fragments, and f) comparison to known profiles in the database. This entire workflow can typically take days or even weeks, and therefore it is not surprising that we see newspaper reports of backlogs of criminal and other property cases. With these time ranges, the sample collected at a site would be of no practical use to most ongoing investigations. Continue reading “Rapid DNA Technology: Establishing your Identity in Less than Two Hours”

Are These the Bones of Richard III?

In central England, an archaeological dig is happening in an unlikely spot—a parking lot in the city of Leicester. The goal: To find the final resting spot of Richard III, the last of England’s Plantagenet kings and perhaps one of its most maligned rulers. Richard III reigned over England for only two years before being killed by Henry Tudor’s army during the Battle of Bosworth Field in August 1485 at the end of the War of the Roses, which pitted Richard’s House of York against the House of Lancaster. Many historical records suggest that Richard’s body was brought to Leicester and buried between the nave and altar at Grey Friars church. You would think that a king’s tomb would be well marked and well remembered, even for an unpopular king like Richard III, but that is not the case here. Henry was said to have erected a memorial for his former rival, but that and any other monuments, along with the church itself, are long gone, destroyed during the Dissolution of the Monasteries, when Henry VIII was named Supreme Head of the Church in England and systematically razed monasteries, convents and friaries throughout England, Wales and Ireland between 1536 and 1541. Since then, the exact location of Richard III’s remains was lost to history. However, thanks to a team of University of Leicester archaeologists and geneticists that might be changing.

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Human Microbiome Project

coliform bacteria

Did you know that the microorganisms living in and on the human body (most on the skin, in the gut, and in the mouth) outnumber all our human cells by a factor of ten? But read on before you grab the hand sanitizer and schedule a colonic, these “germs” may be an integral part of what makes you… well “you”. Indeed, the profile of microorganisms happily living in and on your body may be as unique a signature as your DNA profile or your fingerprints—perhaps more so.

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