How are DNA tests carried out

How does a DNA paternity test work?

4 steps to the paternity test

  1. Take DNA
    The DNA sample is usually a saliva sample, a sample from the cells of the oral mucosa. These cells are easily and painlessly removed with a cotton swab.

    Some tests need to be performed after a participant has passed away. Cell material can also be taken from the dead that can be used for a paternity test. Usually you can use biopsy material or take blood shortly after death. You can also use a razor to reprocess ear plugs, dentures or beard poppers. Laboratories often find enough cell material in them for a DNA test.

  2. Amplify DNA
    The amount of DNA is often insufficient for a test. Therefore, in a first step it is replicated by a chemical process, the polymerase chain reaction

  3. DNA analysis
    The examined gene locations are now evaluated. We have at least 24 markers in the "Standard" test. Up to 40 and more are possible for more difficult analyzes. At the end of the analysis, comparable genetic profiles are available for each participant

  4. statistical evaluation
    With the help of a special computer program, the probability of a relationship is calculated from the available data. A relationship can be ruled out 100%. Confirmed paternity is always a calculated probability from the available data. As a rule, values ​​over 99.999% probability are achieved. With such values ​​for the probability, paternity is then practically proven.

How does the laboratory prepare a paternity test?

We examine the participants' DNA in a paternity test. This DNA is obtained from a swab from the oral mucous membrane, the so-called "saliva sample". This saliva sample can easily be taken with a cotton swab. Blood samples are not required for a paternity test.

We can then not see during the DNA analysis whether there is a possibility of any diseases. Rather, we compare the variable DNA sections with each other in order to find matches and to calculate a possible relationship or paternity from this.

Which samples are suitable for a paternity test?

In principle, DNA that is suitable for analysis can of course be obtained from any body tissue. The fastest and easiest way to do this is to analyze a saliva sample. But DNA can also be obtained from "lifeless" objects such as roots of hair, postage stamps from old letters, combs or razors or even baby pacifiers. We try to get DNA through an abrasion in the laboratory, which can then be analyzed. With the Gendiagnostikgesetz (Genetic Diagnostics Act) it has been forbidden by law in Germany to carry out secret paternity tests. Since every participant now has to agree to the DNA test in writing, it is easier to send us a DNA sample using an oral mucosal swab.

If a participant in a test has already died (it may be a question of inheritance), then we can advise you which type of samples you could send us, from which we then try to obtain DNA that is suitable for a Analysis is suitable.

What is the genetic fingerprint?

DNA paternity tests are a complex scientific process that examines highly variable sections (markers) on the DNA using PCR (polymerase chain reaction). These areas of DNA result in a so-called genetic profile, which is used in the DNA test for paternity.

Since every person has two parents, generally 50% of the characteristics must match those of the mother and, in the case of existing paternity, the other 50% of the characteristics must match those of the tested father. In this case, paternity tests can confirm paternity and proof of paternity is provided.

How Safe is a Paternity Test?

A DNA paternity test can generally give you a safe, reliable result. However, you should always check beforehand which hands you will put your DNA samples into. Is the laboratory in Germany? Has it been checked by external, independent bodies? There are offers for paternity tests in which the DNA samples are sent to laboratories abroad. And, it is clear: if your samples go through many hands before they are examined in the laboratory, mix-up or contamination can also take place in many places. Foreign laboratories often cannot be contacted later if you have any questions about your report. Laboratories in Germany are subject to the Genetic Diagnostics Act. Paternity tests may only be carried out by laboratories that can prove ISO 17025 accreditation. For you as a customer, this is a guide to buy a good and safe DNA analysis.

How long does a paternity test take

We have a standard processing time of a maximum of four working days. This means that if you send us your samples on Monday and also pay for them, we will receive them in the post no later than Wednesday. If you need your test result faster, you can also book our overnight service and receive your result on the next working day.