Welcome to The Forensic DNA Testing BlogThis forensic blog is our official forum where DDC staff and clients can post issues, concerns, answers, and questions regarding forensic DNA testing. Please note that all posts and comments are subject to approval by the moderator. Names may be changed to protect the writer's privacy. |
September 15th, 2015
Advancements in DNA technology has made DNA analysis a revolutionary tool in forensic investigations. Since its breakthrough in the 1980s, DNA is used for identification of individuals in crime scene evidence, unknown human remains, and biological relationships. However, one limitation has been the ability to distinguish between identical twins. Since identical twins present exactly the same DNA profile as each other, their DNA is indistinguishable from each other. Legal conundrums result because it is not possible to tell which of the twins was guilty or innocent of the crime. Rather than risk convicting the wrong person, prosecutors drop charges and a potential criminal is set free.
A new solution to this problem has developed by the Forensic Genetics Research Group at the University of Huddersfield. Led by Dr. Graham Williams, their findings have been published in the Analytical Biochemistry journal. The method is based on the concept of “DNA methylation,” which is effectively the molecular mechanism that turns various genes on and off. The research shows that as twins age, the degree of difference between them grows as each is subjected to different environmental conditions. For example, one twin may be a smoker, one may work outdoors, one may work at a desk. The methylation status of their DNA will thus evolve, making close inspection of the DNA able to reveal the difference between the two individuals. Heretofore the only method proposed for distinguishing the DNA of twins was “mutation analysis”, but this was considered too costly for use in police investigations. Dr. Graham and his team have developed a more cost-efffective method based on this concept, and he explains it this way: ” ‘High resolution melt curve analysis’ or “HRMA” subjects the DNA to increasingly high temperatures until the hydrogen bonds break. This melting temperature may vary between the twins, and therefore the more hydrogen bonds that are present in the DNA, the higher the temperature required to melt them. Consequently, if one DNA sequence is more methylated than the other, then the melting temperature of the two samples will differ-a difference that can be measured, and which will establish the difference between the two identical twins.” Dr. Graham further explains that there are limitations to this solution. First, the technique requires a high quantity sample that may not be present in crime scene evidence. Also, the younger the twins and those raised in highly similar environments, the less likely the development of the methylation differences.
This research demonstrates that scientific breakthroughs continue to offer society more and more tools to solve crime. A detailed summary of the science behind the breakthrough can be found at the blog-site The Conversation (http://theconversation.com/new-dna-technique-means-pointing-the-finger-at-the-right-identical-twin-just-got-easier-39332).
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September 1st, 2015
Yes! Mouth swabs are not only effective for collecting DNA, they are the standard for many applications, including paternity testing, forensic testing, and many kinds of DNA identification. The cells collected from the mouth, preferably cheek cells, slough off in great quantity, and can be stored very easily.
If you’re in your 40’s, you might remember when blood was the only way to collect and find DNA. If there was a crime scene, the detectives needed blood—and hopefully a lot of it—to get a DNA profile. In paternity testing, blood was collected from each party, even infants, in order to compare DNA profiles.
Today, that’s all changed. Technology has changed, from a system called “RFLP” to one called “PCR,” and with that change, a much smaller amount of DNA is needed for DNA testing. In the PCR process, DNA is duplicated millions of times, so a little DNA can turn into a lot of DNA! With this change, a few hundred cells from the inside of cheek can be plenty to establish a DNA profile.
Here are some examples of programs that have been established to collect DNA profiles that you may not know about:
Military personnel. Those that join the military will have their DNA collected right when they join. It can be used to identify bodies when necessary.
Prisoner Inmates. Those that enter prison will have their DNA collected, often to compare their DNA to federal databases to link them to other crimes. The federal DNA database is called CODIS, or Combined DNA Index System.
Paternity Testing. States programs collect thousands of DNA samples every month for paternity testing for child support. DNA can now be collected very easily with cheek swabs, rather than blood samples. The use of cheek swabs for DNA collection has made it possible to even collect DNA at home, creating a new kind of paternity test, where people can find out who the father is without going through the state.
Mouth swabs that collect cheek cells are a very effective way to collect DNA. When dry, these swabs can be stored for decades, and the DNA can still be tested. With simple instructions, anyone can rub a swab on the inside of a cheek and collect enough DNA for a paternity test or any other DNA test. The swabs are not only effective, but they are THE chosen method by most state and federal agencies that collect DNA.
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April 21st, 2015
You’ve seen this plot on TV shows like Law & Order—a woman mysteriously dies, foul play is suspected, and the autopsy finds the woman is pregnant! A DNA test of the fetus is ordered to find out who the father is, and the results usually help solve the mystery and the crime.
There are many similarities between TV cases and a real life murder mystery playing out in Austin, Texas. The difference here is, no autopsy was needed to reveal the twist of an unknown pregnancy–Samantha Dean was seven months pregnant when she was found dead in her car, shot in the head multiple times.
Ms. Dean was a police department Victim Services Advocate, and had been seeing an Austin police officer socially. He has been placed on restricted duty in connection to the investigation.
DNA testing is the key to solving the mystery of who fathered the baby Ms. Dean was carrying. Both Dr. Michael Baird of DDC and Dr. Vincent Di Maio of Bexar County were interviewed by KXAN of Austin, and each agree—DNA results will be very accurate, and “virtually foolproof.”
Here is where the next steps differ greatly from TV shows, where the DNA results seemingly come back the next day. In a case like this, the DNA will most likely be sent through the county or state DNA lab, and the samples will get in line behind dozens, or hundreds, of other cases. Dr. Vincent Di Maio said the tests could take a few weeks to produce results, if there is a backlog in testing. What can happen to a case while a few weeks goes by? Where is the swift justice for the grieving family?
Dr. Michael Baird of DDC, when interviewed, said, “The paternity DNA tests that we do [take] a matter of days. Our typical turnaround time for paternity testing is two days at DDC. DNA analysis of evidence samples can be completed in a few weeks time.” Private labs often can produce test results much faster than county labs. Counties invest in DNA labs for the right reasons, but when the backlogs create long wait times, law enforcement should have a back-up plan to contract with private labs to avoid lengthy delays and relieve time pressure, to promote timely justice for those in need of answers.
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March 3rd, 2015
CINCINNATI, March 3, 2015 /PRNewswire/ –DNA Diagnostics Center (DDC), one of the largest commercial DNA testing companies in the world, celebrates its 20th anniversary today. Headed by President and CEO, Peter Vitulli, DDC is a consumer services company that focuses on DNA testing across multiple channels and segments. It employs over 200 associates and generates a significant portion of sales across international markets via its distributors in over 120 countries.
Peter Vitulli acknowledges the anniversary of the company and its accomplishments, “A personal thanks to the staff and scientists for reaching this important milestone. DDC is the world’s largest paternity testing company and also provides Forensic, Cell Line Authentication, Ancestry, Immigration, and Veterinary-related DNA tests. Last year, DDC launched DDC Direct Connect, a valuable online portal for the company’s Government Contract customers. In late 2014, DDC also became the leading seller of Home Paternity tests in drug stores in the United States.
DDC has one of the largest DNA laboratories in the world with multiple accreditations, including ten individuals who hold Ph.D.’s. For the last decade, the company has been conducting DNA tests in 168 countries, and performs over 600,000 DNA tests annually with more than 4,500 collection sites globally. DDC services the public and private sectors and is the preeminent provider of DNA tests to the entertainment industry, including “Dr. Phil” and “Maury” TV shows, to name a few.
Dr. Michael Baird, Chief Science Officer, is considered the country’s foremost expert in DNA and paternity testing, and was the first person to testify in a criminal DNA case in the US. Since 1987, he has been involved in more than 300 court cases involving DNA and paternity. Dr. Baird is currently the Chair of the Relationship Testing Committee of the AABB responsible for developing standards for paternity testing. He has authored or coauthored over 50 peer reviewed scientific articles involving DNA identification analysis. He was an on-air consultant for NBC during the OJ Simpson trial and the DNA expert in the highly publicized paternity case of Dannielynn, the daughter of Anna Nicole Smith. Dr. Baird received his PhD in Genetics from the University of Chicago in 1978.
On the news of the 20th anniversary, Dr. Baird states, “I am honored to be a member of DDC since 2004. We are proud to help those who are in need of real answers that can change their lives and the lives of their loved ones.” Amongst many “firsts” in the industry, in 2011 DDC launched ‘DDC’s Non-Invasive Prenatal Paternity Test’, empowering customers to learn the paternity of an unborn child as early as 9 weeks in the pregnancy, using a safe, quick, and simple blood collection.
About DDC (DNA Diagnostics Center):
DDC is one of the largest DNA testing companies in the world. Founded 20 years ago, DDC offers comprehensive DNA testing services for paternity and other family relationships, forensics, cell line authentication, and ancestry. DDC receives more than 800,000 consumer calls each year, and will perform over 600,000 DNA tests in 2015. DDC’s unique Dual Process™ ensures all collected DNA samples are independently tested twice producing legal results of unmatched quality and reliability. DDC is recognized through a number of accreditations nationally and internationally including those performed by the American Association of Blood Banks (AABB) and the College of American Pathologists (CAP). DDC is also accredited by ACLASS to meet the standards of ISO 17025 and the American Society of Crime Laboratory Directors Laboratory Accreditation Board International and follows the DNA Advisory Board (DAB) guidelines, which attests to DDC’s superior forensic testing service. For more information: http://www.dnacenter.com or 1-800-625-0874.
To learn more about DDC and to interview Peter Vitulli and/or Dr. Michael Baird, please contact Jan Strode, CEO Advisors 619-890-4040 or JanStrode@aol.com
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December 11th, 2014
Dewey Jones, the Akron OH man who was exonerated of murder and kidnapping charges after serving 19 years in prison for the death of Neal Rankin, has filed a lawsuit against the city of Akron and at least 9 Akron City police officers. In January 2014, Mr. Jones was exonerated after DNA testing conducted by DNA Diagnostics Center helped the OH Innocence Project and Mr. Jones’ lawyers prove to the court that he was innocent of all charges.
Seeking unspecified damages, Jones lawsuit claims Akron Police Dept. investigators of misconduct, including manipulating witnesses and forcing them to identify Jones in photo lineups more than a year after the murder. The lawsuit also claims Akron police detectives used a jailhouse informant who provided false testimony in exchange for protection in that inmate’s criminal cases. Other claims of misconduct include Akron police failing to disclose witnesses identifying other suspects and failing to perform forensic analysis on a bloody handprint found on the victim’s door.
Jones maintained his innocence throughout the case and his 19 years in prison. Even though his trial attorneys argued that there was no physical evidence linking Jones to the murder, the jury sentenced him to life in prison. Ultimately, the efforts of the OH Innocence Project and DNA testing provided by the Forensics team at DNA Diagnostics Center were critical in the Ohio Attorney General’s Office request to vacate Dewey Jones’ conviction.
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