Frequently asked questions about paternity test

How accurate is a DNA test?

The accuracy of a genetic test depends on the methodology used. At LabGenetics we use the most reliable and precise technology used nowadays, which allows us to reach a paternity probability of higher than 99,99% in all cases. If genetic profiles of a alleged father and child do not match in at least 2 analyzed genetic markers, the paternity is rejected with 100% of probability.

From which biological samples can a paternity test be done?

LabGenetics has the necessary technology to be able to analyze with guaranteed results, any kind of biologic sample: blood, saliva, hairs, semen, amniotic liquid, biopsy, skeletal remains, nails, cigarette butt, chewing gum, envelopes, toothbrush or other organic remains present in all kind of clothes or objects.

Is a blood sample test more reliable than one with saliva or other biological sample?

No. All cells of a person have the same DNA, so the accuracy and reliability of the results are the same, independent of the biologic material used.

Is hair a good source of DNA?

Yes and no. For a paternity test to be carried out, the individual hairs must have their root or bulb, which contain the necessary DNA required for a successful analysis (nuclear DNA). For this reason, hairs have to be pulled out and not cut off. A hair which is cut off, without the root, only has DNA named mitochondrial DNA, which is inherited from mother to child, so it will be useful only to do maternity test or maternal biological kinship.

Is it possible to have a paternity test done without a sample from the mother?

Yes. The sample from the mother is not necessary for a maximum guarantee paternity test, while a probability upwards of 99,99% paternity is maintained. If the mother is also analyzed, the probability of paternity is higher than if only the alleged father and child are analyzed, but it is not completely necessary.

Is there a minimum age for a test to be done?

No. A paternity test on a newborn children is possible, as the sample collection of cells from the buccal epithelium of the child is carried out painlessly using a cotton swab.

Is a paternity test possible if the alleged father is dead?

Yes. LabGenetics is equipped to carry out a prenatal paternity test, before the child is born. For this, a sample from the chorionic villus is required, obtained via chorionic biopsy (between the 10th and the 12th week of gestation) or from the amniotic liquid obtained by amniocentesis (between the 14th and 16th week of gestation). Unlike other laboratories, LabGenetics does not need to do a previous cells culture of the amniocytes, so the test results are obtained in just 72 hours after the prenatal sample collection.

Is it possible to do a paternity test if the alleged father is dead?

Yes. In this case, in order to establish the paternity several methodological approaches can be used:

It is possible to do a post-mortem paternity test using samples obtained in autopsy, or through skeletal remains of the alleged father. In the latter case, LabGenetics recommends analyzing teeth (molars) or long and compact bones (femur)
It is also possible to establish paternity through biological remains of the alleged father obtained from his familiar environment (toothbrush, hairs with root, clothes, cigarette butt, envelopes, stamps, etc.) or from hospital environments (biopsy, sperm or blood donations, etc.)
Finally, LabGenetics is prepared to do an indirect paternity test, in which it is necessary to rebuild the genetic profile of the alleged father from biological relatives of the deceased father (parents, brothers, etc.) In this kind of indirect test a correct statistical valuation of the test is fundamental and only a few laboratories are trained to do this.

Does a paternity test carried out by LabGenetics have judicial validity or capacity to be used as evidence in Court of Justice?

It depends. The acceptance of DNA evidence in Court of Justice is subordinated to a correct process of collection, identification and delivery of the samples to LabGenetics laboratories:

With reference to proof of age, it will be necessary to provide ID or any other document that proves their identity. For the identification of minors, either a recent photo will be required, or permission for the LabGenetics staff to take a photo in digital format.
For samples to be taken legally in the case of minors the petitioner is required to prove that he/she has the parens patriae or in the absence of it he/she must prove to be authorized to take samples from them.
In order to ensure the Chain of Custody from the moment the samples are collected until receiving them in the laboratory, the sample collection must be done by health professionals either in any of the sample extraction and collecting points found over the Spanish territory, or directly in the LabGenetics premises in Madrid.

Is it possible to do a paternity test with judicial validity without the express authorization from the mother?

Yes. Nowadays the express authorization from the mother of the minor concerned is not required in order to carry out a paternity test, able to be used in a Spanish court of justice. Due to the existing legal gap in this point, it is the judge himself/herself who has to accept or to reject the genetic report as evidence if the mother of the minor did not give her express consent. It is worth mentioning that, to date, the Court of Justice has accepted all the reports that have been issued by LabGenetics, without express authorization from the mother, as expert evidence.

How can I order a sample collection kit for an anonymous paternity test without judicial validity?

If you wish, LabGenetics will send a sample collection kit together with the necessary instructions and recommendations to your home address, free of charge and anonymously. You only have to fill-in this formulary or print out the application request, filling it in with your personal data and sending it by ordinary mail, fax or e-mail to our center:

LabGenetics
Av. Cerro del Águila, 9 - 28700 San Sebastián de los Reyes (Madrid)
Fax: +34 91 659 22 99 · E-mail: info@labgenetics.com.es

What is the cost of a paternity test?

In LabGenetics we analyze each request individually and depending on the kind of requested test, we adjust our prices to the needs of each client. Call us and ask for your budget.

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