10 Pivotal Pros and Cons of DNA Fingerprinting


DNA fingerprinting is the forensic process of identifying an individual based on an examination of matching DNA strands. Every DNA strand contains a specific code or sequence of genetic information that can be tied to an individual. They are the same in every cell, retain their distinctiveness throughout the entirety of a person’s life cycle, and can be found in blood, bone, hair and skin, and even body fluids.

Sometimes referred to as genetic fingerprinting, the primary advantage of this forensic process is that it adds another layer of evidence in criminal proceedings. Because there is a very high degree of certainty when comparing a found DNA fingerprint to one from a suspect, this evidence has been used to help convict guilty parties or free those who are innocent or may have been wrongly convicted before this technology existed.

The primary disadvantage of DNA fingerprinting is that it is not 100% accurate. Contamination, falsification, and chain of custody concerns still exist with this technology. Even improper testing methods may create false positive or false negative results. Because it is treated as a fact-based piece of evidence, it is possible for false results to be misinterpreted as factual results.

Here are some additional pros and cons of DNA fingerprinting to think about and discuss.

List of the Pros of DNA Fingerprinting

1. It is an unobtrusive form of testing.
A DNA sample is required for matching and comparison. Because DNA can be found in many body fluids and tissues, retrieving materials is a simple and unobtrusive process. Many collectors use a cotton swab to collect saliva from the mouth for testing. Hair follicles can be used as well. That reduces the cost of collection and eliminates the discomfort of needles to collect blood.

2. It can be used for more than criminal justice purposes.
DNA fingerprinting may be used to create genetic profiles for suspects, but this technology can do more than serve the criminal justice system. Products like 23andMe and AncestryDNA can help people research their ancestry. DNA comparisons can identify people who belong to the same family. TV shows like Maury and the Steve Wilkos Show have used DNA testing to confirm parenthood for 10+ years.

3. Collected evidence can be stored indefinitely.
DNA samples do not degrade over time like other forms of forensic evidence. As long as a proper chain of custody and storage is followed, the evidence collected with DNA on it can be stored indefinitely. The DNA from a tooth and thigh bone, fossilized in Spain, were sequenced by scientists in 2016 from samples that were believed to be over 400,000 years old.

4. It can be used to identify hereditary diseases.
DNA fingerprinting is often used to identify certain hereditary diseases that may be life-threatening if not discovered immediately. One of the most important disorders to discover is called PKU, or phenylketonuria. This metabolic disorder may be very rare, with fewer than 20,000 cases per year, but it can also be a lifelong chronic diagnosis. Treatment of PKU involves a very strict diet with limited protein to prevent brain damage from occurring since the body cannot properly process phenylalanine.

List of the Cons of DNA Fingerprinting

1. It creates privacy issues.
With current technology, a collected sample of DNA that has been analyzed can be saved in a database indefinitely. Accessing this information could result in privacy issues, especially if the DNA was collected without permission. DNA is often collected during an investigation to exclude suspects, so there must be a process in place that removes the information collected from innocent parties to prevent a “Big Brother” type of state.

2. Hacking becomes a major concern.
In January 2018, two security vulnerabilities involving the hardware in computers and mobile devices, called “Meltdown” and “Spectre,” showed that hackers could steal data from the memory of an app that is running. These vulnerable processors are in 90% of the world’s devices. Databases of DNA information could be potentially accessible because of security vulnerabilities, creating third-party access to DNA fingerprinting information that could lead to a whole new form of identity theft.

3. It doesn’t remove the idea of a false conviction.
Imagine you’ve gone to the movies with a loved one. As you leave, you suffer from a coughing fit just outside the theater. Maybe you sneeze too. You try to cover up, but some of the saliva and “sneeze juice” hit the ground. You think nothing of it. Three hours later, someone is murdered in front of that theater and your DNA is on the ground, collected by forensic specialists. Guess who just became a murder suspect? DNA fingerprinting may add layers of evidence, but that doesn’t mean the evidence tells an accurate story of what happened.

4. The accuracy of DNA fingerprinting is overly influential.
Although DNA fingerprinting is not 100% reliable, it is often marketed as being an exact science. DNA matching is dependent upon the type of DNA test that is completed. An analyst with the Arizona state crime lab found that two unrelated people matched at 9 of 13 chromosome locations that are used to distinguish identities. The analyst would eventually find 244 individuals, when paired, shared that level of matching and 40 people paired shared 10 markers.

5. It could be used for exclusionary purposes.
A DNA fingerprint can provide a lot of information about an individual. It may show the risks for developing cancer, obesity, or other health problems over time. This information could be used to exclude people from receiving certain medical coverage. It could even be used by potential employers as a screening process as they seek to hire “healthy” individuals. Imagine receiving individualized advertising based on your DNA.

6. DNA banking begins at birth in the United States.
In the United States, almost every newborn has their DNA examined almost immediately after being born. This is done to discover genetic disorders or birth defects, but this DNA information can also be stored in a database for future matching purposes. Some states hold onto the blood-dot cards indefinitely instead of destroying them. The ACLU reports that these blood cards are used for scientific research and even distributed to third parties in some instances.

We all want to live in a society that is safe and peaceful. The pros and cons of DNA fingerprinting show us that this technology is one way to encourage such a society. If used incorrectly, however, this technology could also be used in very destructive ways. That is why it is so important to know what is being done with your DNA and to be careful about who has access to this information.