Does Urine Contain DNA?

Does Urine Contain DNA?


Yes, Urine contain certain traces of DNA in them which will fade on time. Meaning, it will not retain longer in urine compared to blood or saliva. So, does Urine hold DNA? - The answer is NO. Urine may have DNA but cannot hold longer.

Here is all what you want to know about DNA traces in Urine and whether it affects your drug test.

Table Of Contents:

How Long Does The DNA Remain In Urine?

The DNA does not stay in urine for long. After collecting the first specimen, it breaks down within a few days, so not much DNA is left behind. Also, the amount of DNA in urine is so small that it does not give enough information to make an identification. 

DNA stands for deoxyribonucleic acid, and it is the genetic blueprint that makes up all living organisms. DNA contains information that determines how an organism will look, the chemical makeup of the organism, and how it will function. 

Urine, in theory, contains epithelial cells through which DNA is released, but as per studies, a healthy person doesn't excrete epithelial cells in their urine. 

So, preserving urine at -20 °C (-4 °F) should provide a more extended period for the potential recovery of epithelial cell DNA. Thus, through this process, the DNA in urine can be isolated for 28 days.

What Happens To The DNA In Urine?

When a person urinates or defecates, the cells within their body are actively dying. Because of this, the DNA contained in these cells will be broken down by several processes. It is known as lysis

While urine does contain DNA, it is not the complete sequence of the DNA that makes up each cell in the body. As already stated, DNA includes hundreds of thousands of bits of information that our bodies require for proper functioning.

Furthermore, DNA stays inside cells, so there is no reason for urine to have enough DNA left over to test. Even if urine had more DNA in it than generally found after urine leaves the body, it would still not be enough because most of the DNA has been broken down through normal processes. 

DNA that remains after the cell dies is not even the same as the DNA contained in the cells. When cells die, the DNA inside the cell is broken down and becomes part of the serum. 

The serum is what we can measure and test for on a test strip. However, even after all of this has happened, there would not be enough DNA left over to test and read and interpret on a test strip. 

This means that the results from a urine drug test may show negative.

Can Urine Be Used For A Paternity Test?

In most cases, no. Urine does contain a small amount of DNA, but it usually is not enough to get a paternity test. Urine cannot be used for a paternity test. There is not enough DNA in urine for testing because most of the DNA has been broken down by the time it is released from the body, as stated above. 

If there is enough DNA leftover and the sample is of the correct type, it may be possible to do a paternity test, but that would be very rare. There is an exception to this, however, in cases where the child has been born prematurely. 

In these cases, the minimal amount of DNA left over is enough for paternity tests. Urine samples lack stability. Urine usually does not have a very long shelf-life and cannot be used in paternity tests because it quickly changes after leaving the body and loses its ability to retain information. For a paternity test to be reliable, the sample must remain stable for an extended period so that qualified laboratory technicians can test and interpret the results. This is not a case when it comes to a standard drug test. Unlike DNA, the drug traces may stay a bit longer in your urine and hence it can be detected in your urine drug test.

What Is The Most Accurate Way To Do A Paternity Test?

The most accurate way to do a paternity test is through DNA testing. DNA testing is done manually, which means that it needs to be done by a qualified technician. DNA testing is very accurate because it uses the DNA of both the mother and the father to test for biological relationships.

Only through DNA testing can paternity tests be completed to the highest possible standards of accuracy. There are many types of paternity tests, and it is essential to make sure that the test being requested is the right type for the purpose intended. 

However, DNA tests can use cheek swabs or blood tests for an accurate result.

  • Blood tests: 

There are two types of blood tests for paternity which are DNA paternity testing and traditional blood testing. DNA testing is the only type of paternity test that can accurately determine whether a man is his child's biological father. 

Traditional blood tests use the father's blood to determine paternity. Still, this type of test does not always work because many men carry different genetic markers, mistaken for children they fathered in the past. 

  • Cheek swab tests: 

A cheek swab test is a common way to do a paternity test as they are very simple and easy to collect. A cheek swab can be collected from both the child and the alleged father with a small brush or cotton-tipped string, which is rubbed against the inner cheek of each person being tested.

Why do people need paternity tests?

People need paternity tests to establish whether or not they are the biological father of their child. If someone has children, then they want to know who the actual father of their child is.

It is essential for a lot of reasons, including figuring out child support and medical history. Having a paternity test done early on is crucial because it can be used as a tool to help support a custody case or to help do your part in establishing your child's paternity early on in life.

What Is The Most Accurate Way To Do A Maternity Test?

The most accurate way to do a maternity test is through DNA testing, the same way the paternity test is done. 

A DNA test can be performed by swabbing the inside of the woman's mouth, which will then be analyzed for genetic markers. Through this test, not only can you find out whether or not you are pregnant, but also whether or not your child is genetically related to you. 

It is the most accurate way to do a maternity test. Additionally, there are DNA tests that can be done through a blood draw. These maternity tests are more accurate than the cheek swab test because they usually have a longer shelf-life and give you a more precise result.

Does Urine DNA have anything to do with the drug test results?

No. Urine DNA have nothing to do with the drug test results. The drug test is done to analyze the drug metabolites in the urine.

If the drug test comes out as positive, the tester may send it for confirmatory test which traces the drug metabolites in a more accurate way. The confirmatory test cannot detect DNA or other micro-level components in the urine.

Urine Collection And Storage Guidelines For DNA

For a DNA test to be conducted properly, it is essential to follow the principles of urine collection carefully. Since urine can degrade quickly, it is necessary to store it properly for DNA testing. 

The techniques used for urine collection and storage are slightly different from the ones used for blood samples. Blood samples can rely on refrigeration and freezing, while urine samples must be stored at a controlled temperature.

Collecting Urine.

Collecting the urine sample as soon as possible after waking up is advised. When you collect your sample, you will be given a collection cup. Once the cup is filled, please put it in a safe place, and don't forget to close it properly. 

Keeping urine samples.

Keeping the urine samples in a cool and dry place, away from sunlight, at a temperature of 4 degrees Celsius is essential. Keeping your sample at this temperature can help maintain its integrity which will be helpful for DNA testing later on. 

It is also recommended to keep your sample away from moisture, so it's best to store it in places where you don't have humidity issues.

If you are preserving your sample for a drug test, ensure you know about how to keep your urine warm during your drug test.

Preserving the sample for a more extended period.

A urine sample can be preserved for a more extended period by keeping your sample at a lower temperature and making sure it is completely sealed. As mentioned, it must be stored at -20 degrees Celsius or below. 

This temperature could be reached by freezing the sample for two days before storage. Ensure you don't freeze it for more than two days because freezing can also destroy your sample.


Urine is a very common testing medium for both drug and paternity tests. However, urine can only be used for parental DNA testing when the child has been born prematurely. Besides that, urine cannot be used for DNA testing because it lacks the necessary DNA to perform accurate paternity tests.

DNA tests should be done through blood samples or cheek swabs because they are more accurate than urine drug testing.

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