DNA Identification and Consanguinity Analysis
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Frequently Asked Questions (FAQ)


How does a DNA paternity test work ?

Every person has two copies of each gene. One copy comes from the mother and the other copy comes from the father. Thus, one half of the genetic material in our body is inherited directly from each of our two parents. When a DNA- paternity test is performed, our DNA laboratory examines the DNA of the child to determine whether the father's contribution matches that of the alleged father. If the alleged father is the true biological father of the child, half of the child's genes will match that of the alleged father's. The other half comes from the mother and will match the profile of the mother (testing the mother is optional). If the tested man is not the biological father of the child, the half of the child's genetic material which comes from the father will not match the DNA-profile of the tested man. If the DNA-profile does not match, the tested man is excluded as being the true biological father of the child. When a DNA paternity test is performed, the laboratory usually examines many different genetic locations. The more genetic locations that are examined, the more powerful and accurate your test becomes. After examining many genetic locations, a DNA lab can conclusively determine whether the tested man is indeed the true biological father of the child. Our paternity test report will provide you with a simple "yes" or "no" conclusion for your paternity test as well as a detailed report indicating the DNA-profiles of each tested individual.  

What is a genetic locus or marker?

Since it is not possible to analyze all of a person's DNA, in practice, specific genes are selected for analysis. These genes typically do not code for any physical property of the individual, but are chosen for their properties of being easily analyzed and having a high discriminating power in identification and consanguinity analysis. 
A genetic marker is a piece of DNA (or a gene) that everyone has, but that can, in each individual, be one of a few different forms that occur in the population (alleles). The pattern of alleles that a person carries for set of genetic markers is called a DNA profile.

What is a DNA profile?

The pattern of alleles that a person carries for set of genetic markers is called a DNA profile or a DNA-fingerprint. A DNA profile is similar to a real fingerprint in that its pattern is unique for each individual and hence can be used to unequivocally identify an individual. DNA profiles are comparable only if they describe the same loci. Comparison of genetic fingerprints can yield information on consanguinity because each half of our genotype for every genetic markers is inherited from one parent.

What are STR analyses?

STR stands for Short Tandem Repeats or short equally oriented repetitions in the DNA sequence. STR loci are loci whose alleles differ in the number of repetitions of successive base pairs, which makes them easier to distinguish because the difference between two alleles is an integer multiple of the length of the repetition. The loci that are in standard use in the forensic world and that are used in the big DNA databases of international law enforcement agencies and the FBI, are all STR loci.

What is a sample kit and how do I obtain a sample?

You may order a kit using our web form, or by telephone at +32-485-471309. 
The kit contains everything you need to take one or more samples under optimal conditions. These should then be forwarded to us. 

I have a toothbrush, cigarette butt, saliva stain... that needs to be analyzed. What now?

If you already have our sample kit, just follow the enclosed instructions and put the sample in the tube, label the kit and mail it to us.

We do not accept hair or finger/toe nails for analysis.

Take care to protect the sample as much as possible against contamination with other human DNA. Try, in the mean time, to keep the sample dry, to prevent bacterial breakdown of the human DNA. Use clean tweezers to insert the sample in the vial or sample pouch.

Preferably use the cotton swab (bud, Q-tip), included in our test kits, to harvest cells from the mouth by rubbing the swab a few times vigorously against the inside of the cheek. Then put the swab , cotton end first, in the vial and use scissors to cut any excess length such that the vial can be closed. After shutting the vial, label the sample with a reference number of your choice (use the label provided with the kit). If necessary use transparent adhesive tape to fix the label.  

How soon can the analysis results be available?

Under normal circumstances you will receive the results from the DNA analysis within two or three weeks after our receipt of the samples. The limiting factors here are the quality of the samples and the capacity of the lab equipment.

Express Service

We can't guarantee a maximum turnaround time, but in urgent cases, and with good quality samples results can be available in a few days after receipt of the samples.
Call us at +32-9-241 5636 to discuss how to most efficiently get the samples to the lab.

What kinds of samples can be analyzed?

In principle, anything that contains human cellular material, even a smear or a smudge, can be used. To take a sample in ideal conditions, it is best to use a cotton swab or Q-tip and rub it gently on the inside of the cheek and under the tongue (cf. the sample kit for the parental testing)

Even traces of DNA (very small quantities) are sufficient for a successful analysis. A post-stamp that was licked will usually contain sufficient amounts of saliva to contain human cellular material. A cigarette butt, a toothbrush, the stick of a lollipop, a dummy teat (pacifier), a razor blade, a stain on underwear, scales of skin from a sheet or pillow case, a used handkerchief, a worn garment, a used condom, 0.1 ml of urine, a blood stain on paper or cloth are acceptable as well. These are all examples of samples that can yield DNA profiles and can serve for identification or kinship analysis.

Hairs and fingernails contain very little or no genomic DNA and are not accepted for analysis. 

How long will a sample retain its quality?

DNA is quite stable, and, under most circumstances can be stored for a long time with no degradation. It is always a good idea to keep samples dry. Humidity can cause bacteria and fungi to grow, and consume human DNA traces.
So send your samples quickly, or dry them first!

How to properly collect DNA samples

Use a clean cotton swab (Q-tip) to scrape some saliva from the inside of the cheek of each test participant. Make sure that every sample only contains DNA from one single person and package the samples separately to prevent cross-contamination. Label each sample, indicating whether it contains DNA from the child or the alleged father. Include the analysis fee (or proof of payment) with the samples and label the envelope with an identification code of exactly 8 alphabetic characters ('A'-'Z'). Download, print and fill out the order form.

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