What Is A DNA Fingerprint?
Did you know that every person has a DNA fingerprint? By studying unique patterns, you can be identified from a small sample of your DNA.
Most commonly, DNA fingerprinting is used as evidence in criminal cases or to identify bodies.
It can also be used to find blood relations or even assist in finding a cure for a disease.
Keep reading to learn more about the power of DNA fingerprinting.
We All Have A DNA Fingerprint
On average, humans share about 99.9% of their DNA. At first glance, you might think that it does not make us very different from one another.
But the truth is, every person has their own unique DNA fingerprint. The one caveat here is if you are an identical twin, you likely share DNA with your twin.
The likelihood you would share the same DNA with someone who is not your identical twin is very slim.
Despite humans sharing such a significant amount of DNA, two people will have more than three million different base pairs.
All those differences add up to help distinguish you from another person.
Similar to our actual fingerprints, your DNA fingerprint is something that is with you from birth, and is unique to you alone.
Discovering DNA Fingerprinting
In 1984, DNA fingerprinting was invented by Professor Sir Alec Jefferys.
Professor Jefferys realized that human DNA variations could be detected by using minisatellites, short sequences of DNA that show variations from one person to another.
Through the examination of minisatellites in the genome, a pattern is produced that is unique to each individual.
How To Get Your DNA Fingerprint
To find someone’s DNA fingerprint, technicians need a sample of DNA.
This sample can simply be taken from a cheek swab, a piece of skin, the roots of air, a saliva sample, sweat or other bodily fluids. Most commonly, a blood sample is taken.
Technicians then apply chemicals to separate the DNA and dissolve it in water.
From there, another chemical process is implemented to cut the DNA into even smaller pieces. In the end, the lab technician is left with five to ten base pairs of DNA.
Those little sections are copied millions of times to make longer samples that are later studied.
Once those strips of DNA have been created, they are mixed with a gel substance. An electric current runs through the gel which helps to separate smaller DNA strands from bigger ones.
A dye is usually added to the gel so the DNA strips become more apparent and easy to see with ultraviolet light.
Once these smaller DNA strips are tested, they display something similar to a barcode pattern.
From there, the DNA strips can be compared with other samples of DNA to locate a match.
You may have heard the phrase DNA profiling or be familiar with the general concept.
DNA profiling differs from a DNA fingerprint and unless you are a scientist or researcher, you may not know how the two techniques differ from one another.
As discussed, DNA fingerprinting uses minisatellites to establish your DNA fingerprint while DNA profiling relies on microsatellites.
What are microsatellites? They are short tandem repeats (also known as STRs) that are shorter relatives of minisatellites.
These microsatellites are typically two to five base pairs long.
Similarly to DNA fingerprinting, DNA profiling is used to solve crimes, reveal disaster victims, and match people with unknown family members.
Solving Crimes And Linking Families
There are some circumstances in which a body cannot be identified and scientists need to find, identify, and study a DNA sample from the body.
One example of this is in the event of a major disaster. The 2004 earthquake and tsunami in Thailand had devastating effects and killed around 230,000 people.
With such large numbers of deceased people, authorities needed to rely on DNA technology to help identify them and provide closure to their family members.
DNA fingerprinting can also be used in more positive cases.
Once your DNA has been studied, it can be compared with the DNA of others all over the world to identify genetic similarities and matches.
This can help connect family members that have never met and even assist with a transplant or provide important medical information related to the family as a whole.