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Yes, it’s possible to get DNA from ashes. DNA testing is often done on the bodies of the dead, even after they’ve been cremated. Tests are also performed when people are killed in fires to identify their remains.
You can get DNA from bone fragments and it is possible to conduct a DNA test on the fragments. It’s unlikely that all of the bones of a burned body will completely disintegrate. DNA testing is possible as long as there are bone fragments. If there are no bone fragments, a successful test is unlikely.
Fire can damage DNA beyond recognition. How much you’re able to identify through DNA testing on burnt remains varies from situation to situation.
The simplest answer to this question is “a very long time.” One of the reasons DNA is such a valuable tool is because of how long it lasts. Decades or more after a person dies, it is still possible to extract and test DNA.
This doesn’t mean DNA lasts forever. As the body decomposes, less and less DNA is available for testing. Exposure to the elements speeds up the DNA decay process, so a body that has been in water, sunlight, or heat will provide less DNA information than a body that was better protected. If a body is not properly protected from the elements, DNA could be unavailable in as little as a few weeks.
However, scientists estimate that DNA could be available for up to a million years if a body is protected. The oldest DNA sample on record came from Greenland and was preserved beneath a mile of ice. It’s likely between 450,000 and 800,000 years old. The oldest human DNA sample comes from a 7000-year old sample. Scientists used mitochondrial DNA from the sample to identify its origins.
Ultimately, how long DNA lasts is based on many different factors, many of which are uncontrollable.
Yes, teeth and bones are the best sources of DNA from human remains. In many cases, they are the only source. Teeth protect DNA because of their construction and location. This means that even if DNA has been otherwise destroyed, a person’s teeth or tooth fragment can provide insight into their identity and their genetic makeup.
The DNA that’s extracted from under tooth enamel is great for testing because the enamel is so hard. It offers good protection and slows the deterioration of DNA. Most of the time, teeth are the last of a person’s remains to decompose, so DNA is available long after the person has died.
In addition to using DNA from teeth to identify someone, DNA testing is also being used to determine if someone has gum disease. In the past, the only way to identify gum disease was by examining the gums once there was a noticeable presence of a problem. But nowadays, DNA testing eliminates the need to wait for visual clues. This means gum disease is treatable as early as possible, reducing the risk of complications and other related health problems.
Embalming is the process of preserving a body after it dies. It temporarily delays the decay and breakdown of cells. In most cases, the delay is just a few days or weeks, which gives the family time to mourn and display the body for the funeral or transport it.
Embalming fluid that contains bleach will degrade DNA. It also interferes with the ability to gather information about blood group antigens, which are used to determine a person’s genetic makeup. This is the case regardless of the chemicals used in the embalming process. However, it would still be possible to use the DNA from a person’s bones and teeth to gather a sample that could be used.
The most obvious reason you’d conduct DNA testing on a person’s remains is to identify who they were when they were living.
But that’s not the only reason. Some people test ashes to determine that the remains they have are truly their loved one and not another person’s ashes. Problems with funeral homes and crematoriums are rare, but they do occur. Anyone who wants peace of mind and to know that the remains they received are truly those of their loved one can use bone fragments in the ashes for DNA testing.
“Can You Get DNA From Human Ashes? Usually No, But This Is How !” Funeral Direct, 3 May 2018, www.funeraldirect.co/can-you-get-dna-from-human-ashes. Accessed 1 Dec. 2020.
“How Long Does DNA Last?” Www.Mentalfloss.com, 13 Feb. 2013, www.mentalfloss.com/article/48815/how-long-does-dna-last.
“All List of Chemicals Used in Embalming - Substances and How It Works.” AZ Chemistry, 19 Dec. 2018, azchemistry.com/list-of-chemicals-used-in-embalming. Accessed 1 Dec. 2020.
Higgins, Denice, and Jeremy J. Austin. “Teeth as a Source of DNA for Forensic Identification of Human Remains: A Review.” Science & Justice, vol. 53, no. 4, Dec. 2013, pp. 433–441, www.sciencedirect.com/science/article/pii/S1355030613000579, 10.1016/j.scijus.2013.06.001. Accessed 7 Jan. 2020.