Is Buccal Sampling the Only Way to Obtain a Sample?

The answer is no. Thanks to various advancements in medical and scientific research, it is now possible to conduct a reliable DNA test from any cell in the human body. Whether it's a strand of hair or a broken nail, DNA extraction is always feasible.

When should non-buccal sampling be carried out?

Searching for paternity links is a common process in France. Cases where buccal swabbing is impossible are frequent, especially when the individual has disappeared or is deceased.

However, laboratories can perform analyses on other types of samples. For these non-standard methods, the reliability rate of the results is slightly affected due to the type of sample and its age.

The Importance of the Sample's Age

For a sample to be usable, it must contain enough material. The age of the sample is also very decisive. The success rate of DNA extraction indeed varies according to these two factors.

Success Rate

This rate can reach over 90% on a femur bone, frozen sperm, or fresh blood from 30 to 60 days. These organically sourced elements, if well-preserved, yield good results.

It is between 70% and 90% for tissues like handkerchiefs, ear wax, nails, dried blood spots, muscle tissue samples or unembalmed organs, liquid sperm, the umbilical cord.

Finally, the success rate can be less than 70% for certain organic tissues or for any extraction performed on objects or tissues that have been in contact with the person tested: cigarette butts, teeth, post-mortem body tissues, razors, hair, bristles, toothbrushes, chewing gum, straws, cans, baby bottles, etc.

How to Collect?

The conditions under which the collection takes place can also affect the results and the quality of the materials. A sample must not be contaminated during handling. You must ensure several things:

• Wash your hands before proceeding
• Wear gloves or avoid direct contact with your fingers to prevent DNA transfer
• Ensure that the container or envelope in which you seal it is airtight and sterile.