You have received your tellmeGen kit, you are curious about your ancestry, and you want to know your genetic predisposition to certain health conditions. It’s exciting! But, before you start, stop for a second. Although collecting saliva seems simple, the quality of your DNA depends on how you do it.
A contaminated sample or one with low DNA can fail in the laboratory, which means repeating the process and waiting longer for your results. To avoid this, we have compiled the most frequent mistakes and how to fix them.
1. The main mistake: Eating, drinking or smoking before the test
This is the number one reason for failed samples. If there are remains of food, coffee or tobacco, the DNA we extract will not be pure.
· How to avoid it: Do not eat, drink (not even water), smoke, chew gum or brush your teeth 60 minutes before collection.
· Expert advice: Ideally, take the sample on an empty stomach, as soon as you wake up. This is when the concentration of cells in the mouth is at its highest.
2. Medication and water: The timing dilemma
If your medication requires drinking water, this "washes" the cells from your mouth.
· How to avoid it: Take your medication after performing the test. If it is strictly necessary to take it before, do so with enough time in advance so that your mouth can generate natural saliva again before the test.
3. Have you received a bone marrow transplant?
This is a critical point. If you have had a marrow transplant, the DNA in your blood and saliva will be that of the donor, not yours.
· What to do: In this case, the genetic test will not provide your personal results. If this is your case or that of someone for whom you have bought the test, contact our team before proceeding. You can read more about this here.
4. Health status: Are you going through an infectious process?
If you have a severe mouth infection, mouth ulcers or are receiving aggressive treatments such as chemotherapy, the structure and quantity of epithelial cells may be altered.
· How to avoid it: If you feel unwell or have an irritated mouth, wait a few days to recover. We want your DNA to be in "top shape".
What happens if my sample fails?
Do not panic. Sometimes, despite following all the steps, the sample does not contain enough genetic load to be processed. At tellmeGen we take precision very seriously, so if a sample is not valid, we will contact you to find a solution.
Discover more details here about why a sample may not be valid and how we solve it.
