Genetic Identity and Forensics

Bones: Improved Technology is Bringing Loved Ones Home

Posted on by Promega
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Many crime labs do not have protocols in place for the extraction of DNA from skeletal remains or have outdated protocols for bone extraction that are not sensitive enough for poor quality bones.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.

Continue reading “Bones: Improved Technology is Bringing Loved Ones Home”

Familial Searching Solves Cold Cases—At What Cost?

Posted on by Darcia Schweitzer

A cold case that had stumped investigators for nearly 41 years was solved last month. The 1976 sexual assault and murder of Karen Klass, ex-wife of Righteous Brother’s singer Bill Medley, shocked her Hermosa Beach, CA community and captured the public interest. Failing to make any arrests for decades, detectives were able to use DNA evidence to eliminate suspects in 1999 but were unable to find a database match. In 2011, investigators decided to try a new technique called a familial search and, after a few attempts, successfully identified the perpetrator.

DNA-Handcuffs-double-exposure-R2

Familial searching (FS) involves taking a DNA profile obtained from a crime scene and comparing it to profiles in CODIS and other databases to identify male relatives. The DNA profile of an immediate family member, such as a sibling, parent or child, can provide a match that generates new leads for law enforcement. Detectives can then collect additional evidence to narrow down that new pool of individuals to a single suspect.

Last May I wrote a blog featuring a Q & A about FS provided by Mr. Rockne Harmon, a respected member of the forensic community and passionate advocate for FS. Supporters, like Harmon, and opponents agree that this method of obtaining matches to DNA evidence has demonstrated scientific precision and successful outcomes, as in the Klass case. However, it is still considered controversial and most states have not implemented specific policies regarding the application of FS to criminal investigations. So why isn’t the use of FS more widespread?

Continue reading “Familial Searching Solves Cold Cases—At What Cost?”

We Need More Conferences Like ISHI: Memoirs of a First Timer

Posted on by Greg Emmerich

Keynote speaker David O’Shea kicked off the ISHI 27 conference with his investigation on how DNA profiling is helping to reunite families in Argentina after the military coup in the late 70’s.

We shared in laughter and tears. We tempered our scientific pursuit of the truth with the story of an unimaginably strong survivor of rape. We witnessed the struggles of a man trying to find his identity and the joy of being reunited with real family members after 30 years of lies. I find it hard to succinctly describe to others what my first ISHI conference was like. There is perhaps nothing more personal than our own genetic identities. This conference didn’t shy away from the raw emotions that encompass the human experience. We define ourselves as employees of this company or researchers at that institution, competing for attention and funding, yet this conference reveals how limiting these preconceptions may be.

The desire to make the world a better place unites us. I spoke with analysts for hours about the challenges of overcoming the sexual assault kit backlog, I made a fool of myself dancing to musical bingo with new friends from the Philippines and Brazil, and I was inspired by the casual musings of a video journalist. We are sure to see countless more ethical debates on how we should be using DNA (or proteins!) for human identification. The field of science relies on the open sharing and exploration of new ideas, and as admittedly biased as I am to the conveniences of the digital age, there has never been a better time to come together in person.

Don’t just take my word for it, though.

There were some phenomenal talks each day, and I did my best to capture the essential takeaways from Continue reading “We Need More Conferences Like ISHI: Memoirs of a First Timer”

Of Elephant Research and Wildlife Crime – Molecular Tools that Matter

Posted on by Nicole Sandler

Here at Promega we receive some interesting requests…

Take the case of Virginia Riddle Pearson, elephant scientist. Three years ago we received an email from Pearson requesting a donation of GoTaq G2 Taq polymerase to take with her to Africa for her field work on elephant herpesvirus. Working out of her portable field lab (a tent) in South Africa and Botswana, she needed a polymerase she could count on to perform reliably after being transported for several days (on her lap) at room temperature. Through the joint effort of her regional sales representative in New Jersey/Pennsylvania (Pearson’s lab was based out of Princeton University at the time) and our Genomics product marketing team, she received the G2 Taq she needed to take to Africa. There she was able to conduct her experiments, leading to productive results and the opportunity to continue pursuing her work.

Continue reading “Of Elephant Research and Wildlife Crime – Molecular Tools that Matter”

The Cell Line Identity Crisis

Posted on by Nicole Sandler
29981164-Whistle

If you work with cell lines you may have paid attention to the dramatic headline published last month in the online journal STAT, Thousands of studies used the wrong cells, and journals are doing nothing.” In their column The Watchdogs (“Keeping an eye on misconduct, fraud, and scientific integrity”), Ivan Oransky and Adam Marcus call out the fact that scientists continue to publish research using cell lines that are contaminated or misidentified. Recent estimates have found that the percentage of misidentified cell lines used by scientists is as high as 20 to 36. The blame here is being placed on the peer reviewed journals for not blowing the whistle. The authors call for journals to put some “kind of disclaimer on the thousands of studies affected.”

This is not a new claim. The continuing problem of cell line misidentification, of lack of authentication, has been covered before in various channels. It’s easy to find news publicizing yet another retracted publication. In May 2015 the journal Nature required authors of all submitted manuscripts to confirm the identity of cell lines used in their studies and provide details about the source and testing of their cell lines.

Continue reading “The Cell Line Identity Crisis”

Ten Validation Tips You Need to Know

Posted on by Promega
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.

Previewing ISHI 27: Mitochondrial DNA Analysis in Forensic Investigations

Posted on by Isobel Maciver
Credit: National Institutes of Heath, USA
Mitochondrial DNA has important implications for forensic analysis. Image Credit: National Institutes of Heath, USA

mtDNA heteroplasmy was key to identifying the remains of Tsar Nicholas II
mtDNA heteroplasmy was key to the identification of the remains of Tsar Nicholas II

Heteroplasmy is the presence of more than one mitochondrial genome within an individual. Perhaps the most famous example of the effect of mtDNA heteroplasmy on a forensic investigation is the identification of the remains of Tsar Nicholas II. mtDNA from bones discovered in a mass grave in 1991, was identical in sequence to known relatives of the Tsar except at one position, where there was a mixture of matching (T) and mismatching (C) bases. Lingering doubt caused by this result meant that confirmation of the authenticity of the remains was delayed. Ultimately mtDNA analysis provided the needed evidence for identification, showing that the same heteroplasmy was present in mtDNA extracted from bones of the Tsar’s brother, confirming the Tsar’s identity (Ivanov et al., (1996) Nature Genetics 12(4), 417-20).

Here is what Dr. Holland had to say about the work he will present at ISHI:

Continue reading “Previewing ISHI 27: Mitochondrial DNA Analysis in Forensic Investigations”

Discovering the Truth About the Dozier School for Boys

Posted on by Greg Emmerich
Dozier School for Boys gravesite
Photograph from The Tampa Bay Times

The Dozier School for Boys had cemeteries instead of playgrounds.

The stories of abuses that took place at the reformative school in Marianna, Florida are nothing short of a plot for the TV series American Horror Story. The beatings and other punishments administered to students throughout the school’s 111-year history contributed to the deaths for some of the nearly 100 deceased.

A 2010 investigation by the Florida Department of Law Enforcement did not lead to criminal charges against the school because there was “no tangible physical evidence for allegations of physical and sexual abuse.” The full report is available on The White House Boys Survivors Organization’s website, a name derived from the shed where the boys were beaten with wooden panels and leather straps. At the time, only 32 unmarked graves were known in the school’s cemetery.

Continue reading “Discovering the Truth About the Dozier School for Boys”

Familial DNA Searching for Criminal Forensics: Q&A

Posted on by Darcia Schweitzer

When DNA evidence is collected at a crime scene, submitting the sample for a search within a DNA database does not always identify a profile match. There is a way to extend that search and generate leads, called familial searching (FS). FS is used to identify close biological relatives of an unidentified DNA profile obtained as evidence. The basic premise is that DNA profiles of immediate family members, such as siblings, parents, or children, are likely to have more alleles in common than unrelated individuals. These familial profile matches can generate new investigative leads for law enforcement.

Currently, a few states are using FS under their state database laws, although none explicitly permit FS. Many agencies have yet to adopt policies related to FS, even though it has been found to be as effective as CODIS for identifying sources of evidence. The absence of clear ethical guidelines and policy regarding how to properly utilize FS prevents many local and state jurisdictions from adopting this investigational tool.

In order to address concerns and existing policies related to FS and to guide policy decisions by agencies implementing FS, the National Institute of Justice (NIJ) issued the report Familial DNA Searching: Current Approaches in January 2015. The goal of the report was to provide information to policy makers, law enforcement officials, forensic laboratory practitioners, and legal professionals about how FS is being applied within the criminal justice realm.

Mr. Rock Harmon, former prosecutor
Mr. Rockne Harmon, former prosecutor

Answers to the following questions about FS were provided by Mr. Rockne Harmon, a retired former prosecutor and member of the team that produced the report for the National Institute of Justice.

What is familial DNA searching?

Familial searching (FS) is an additional search of a DNA profile in a law enforcement DNA database that is conducted after a routine search fails to identify any profile matches. The FS process attempts to provide investigative leads to agencies engaged in the pursuit of justice by identifying a close biological relative of the source of the unknown forensic profile obtained from crime scene evidence.

Continue reading “Familial DNA Searching for Criminal Forensics: Q&A”

ISO 18385: The Creation of a “Forensic Grade” Standard

Posted on by Promega

Today’s blog is from guest blogger Charles Stollberg. Charlie is a Promega production scientist in the Genetic Identity group and is focused on manufacturing inventory material and production process improvements. He’s been with the company for about 4 years. He graduated from UW-Whitewater in 2007 with a bachelor’s degree in cell biology. Prior to Promega, he worked in a small genetics lab studying lethal recessive traits in cattle.

ForensicGradeLogoForensic DNA laboratories rely on reagent and plastics manufacturers to supply high-quality products with minimal interference from contaminating DNA. With the increasing sensitivity of short tandem repeat (STR) amplification systems, levels of DNA that were previously undetected may now generate partial profiles. To address the concern of laboratories worldwide regarding the potential of low-level DNA contamination in consumables, ISO 18385 was developed to provide requirements for minimizing the risk of human DNA contamination events during the manufacturing process. Many of you may not have heard of ISO 18385, so I’d like to give you an introduction to how the standard came to be.

Continue reading “ISO 18385: The Creation of a “Forensic Grade” Standard”