29/02/2020
There is no end to the learning curve for a family historian.
I have recently watched this awesome seminar by a world leader in DNA research in regards to Law Enforcement. I am often asked about this when talking to clients about taking a DNA test. I have a short intro video below FYI. If you are worried, please watch this hour-long webinar as I have because it is very good.
The short answer is ... there is nothing to worry about.
A longer answer is ....
In the USA, Law Enforcement uses STRs (Short Tandem Repeats) of DNA to store in a database that they call CODIS (COmbined Dna Index System). If they arrest someone, they take fingerprints and DNA for STR testing. These results are stored in a massive database (CODIS).
If they get DNA from a crime scene, they do STR testing and look for a 100% match in CODIS. That is traditional Law Enforcement DNA testing in the USA.
Now, ancestry DNA testing uses SNPs, or Single Nucleotide Polymorphisms, frequently called SNPs (pronounced βsnipsβ), which are the most common type of genetic variation among people. Each SNP represents a difference in a single DNA building block, called a nucleotide. For example, an SNP may replace the nucleotide cytosine (C) with the nucleotide thymine (T) in a certain stretch of DNA.
Ancestry Autosomal DNA looks for a percentage match to see, firstly, if the 2 samples are related and, secondly, how closely they are related.
So, traditional Law Enforcement DNA was searching for a 100% match, but ancestry DNA is a completely different test procedure and it is looking for a percentage match.
I am unsure what (or if) DNA testing has been used by Australian Law Enforcement.
Please ask if you have any questions about DNA tests.
https://www.rootstech.org/video/dna-genealogy-and-law-enforcement-all-the-facts?fbclid=IwAR3jPOyxX5rMuLU2eF93ZZN5Wm6hVrtimdWorY5IIHQSNtkBchzH7Q_gefM