The following glossary provides clear explanations of the most commonly used terms and concepts in DNA relationship testing.
Accreditation
A process by which an independent (often governmental) organisation verifies that a laboratory or testing body operates according to pre-defined rules and standards. Accreditation provides assurance that the work is carried out correctly and that the results issued are reliable.
Acknowledgement of Paternity
Where the law does not provide otherwise, paternity may be acknowledged by a formal declaration. In such cases, the person making the declaration is presumed to be the father and is entered into the child's birth register accordingly.
Allele
Variable-length units of the DNA molecule located on a chromosome, also referred to as a locus. Every allele coding for a given trait is inherited from two sources — the mother and the father — and enters the child's cell nucleus, DNA molecule and chromosome accordingly. During paternity testing, the lengths of specific alleles characteristic of each individual are compared.
Paternity Declaration
If the mother of a newborn child is not married and does not have a registered partnership, the child's father may declare in a formal statement that he is the father. In this case, the authority presumes the declarant to be the father, and he is entered into the child's birth register as such.
Paternity Test
The examination of the biological genetic relationship between a minimum of two individuals — typically a child and an alleged father.
Identity Verification
During a court-admissible paternity test, within the controlled chain of custody process, the identity of each person tested must be verified. This is carried out by an independent sample collector on the basis of identity documents, witnesses and photographs, and must be recorded in an official protocol. In court proceedings, the sample collector's declaration confirms that the biological material genuinely originates from the individuals named in the documentation.
Establishing Paternity
During a DNA paternity test, the lengths of a pre-defined minimum of 21 DNA markers (alleles, loci) are examined and compared between the child and the alleged father. If two or more allele lengths are incompatible, the alleged father can be excluded as the biological father. Conversely, if the markers are consistent, the probability of paternity is calculated based on the population frequency of the tested markers.
Challenging the Presumption of Paternity
If a person obtains information suggesting that the presumption of paternity affecting them is questionable, the presumption may be challenged in court within one year of becoming aware of the relevant facts.
Biological Father
The biological father is the person whose genetic material is clearly identifiable in the child's genetic profile — the child is descended from him by blood. In some cases, he may not be the presumed legal father, and a paternity test is able to resolve this question definitively.
Family Relationship Testing
DNA-based testing is not limited to the father–child relationship. Other relationships — such as grandparent–grandchild, sibling, uncle/aunt–nephew/niece, and others — can also be tested.
DNA
DNA (deoxyribonucleic acid) is a specialised molecule that forms the chromosomes of the cell nucleus and carries hereditary genetic information. A child inherits half of their genetic information from the mother and the other half from the father. The DNA molecule is made up of nucleic acid bases, of which there are four different types; their sequence determines the genetic information encoded.
DNA Profile
The genetic information encoded in DNA is unique to each individual — like a fingerprint. A person's DNA profile does not change throughout their lifetime. It is possible to have a DNA profile analysed, which can then be used in any future family, ancestry or legal proceedings.
DUO Test
A paternity test in which only the DNA samples of the child and the alleged father are processed.
Alleged Father
The individual being tested, in whose case the paternity test determines whether he can be excluded as the biological father of the child, or whether paternity can be confirmed.
Gene
The section of the DNA molecule that carries information relating to a specific trait.
Gene Locus
The precise location of a gene on the DNA molecule that carries information for a given trait.
Twin DNA Test
A DNA-based test used to determine whether twins are identical (monozygotic) or fraternal (dizygotic). In the case of identical twins, the DNA profiles of both individuals are the same, whereas fraternal twins share a level of DNA similarity comparable to that of ordinary siblings. DNA-based twin testing is the only accepted and reliable method for resolving this question.
Chromosome
A structure found in the cell nucleus, composed of DNA molecules carrying the genetic code. Every cell contains 46 chromosomes — 23 pairs — of which the child receives 23 from the mother and 23 from the father at the moment of conception. Their composition does not change and remains identical in every cell of the body throughout life.
Marker
A well-defined short segment of the DNA molecule that can be used to describe a particular trait — including, for example, paternity.
Sampling Kit
A self-contained package containing everything needed to collect a DNA sample and submit it for testing: the swabs required for buccal sample collection, the documentation needed to carry out the test, a pre-addressed return envelope, and a unique barcode for payment identification. The kit can be ordered by post or collected from a participating pharmacy.
Polymerase Chain Reaction (PCR)
A fundamental laboratory technique used to amplify nucleic acids (DNA, RNA), enabling most genetic tests — including paternity testing — to be carried out with a high degree of accuracy.
Buccal Swab
A specialist sampling swab, similar in appearance to a cotton bud, supplied in pairs. It is used to collect epithelial cells from the inner surface of the cheek by rubbing the cotton-tipped end firmly against the buccal mucosa approximately 10 times. The procedure is painless, leaves no marks, and can even be performed on a sleeping infant without waking them. Once dried (stored in a paper envelope), the sample remains stable at room temperature for several months and can be sent conveniently by post, sealed in an envelope.
TRIO Paternity Test
A paternity test that includes DNA samples from the child, the child's mother and the alleged father.
Presumed Father / Presumption of Paternity
Under the Hungarian legal system, paternity is established on a presumptive basis. The father of a child is the person who was — or is presumed to have been — the mother's spouse or registered partner at the time of conception, or who acknowledges paternity by formal declaration. The presumed father is not necessarily the child's biological father.
Blood (EDTA Blood)
An anticoagulated laboratory blood sample that can be used for paternity testing. Historically, paternity tests were conducted using blood samples; today, this is used only as a specialised sample type, and testing costs are higher in such cases. The result of a blood-based paternity test is identical to that obtained from a buccal swab ("saliva") DNA sample.
Non-Invasive Test
A testing method that does not require any invasive procedure (such as needle insertion or amniocentesis). Non-invasive prenatal paternity testing, for example, is performed using the mother's blood sample and is therefore entirely safe for both mother and foetus.
Prenatal Paternity Test
A paternity test performed before the birth of the child, using the mother's blood sample. This modern method makes it possible to establish biological paternity at an early stage of pregnancy.
Foetal DNA
DNA fragments originating from the foetus that circulate freely in the mother's blood during pregnancy. By analysing these fragments, it is possible to determine certain genetic characteristics of the foetus — such as its sex or biological father — before birth.
Genetic Fingerprint
The unique pattern of an individual's genetic information, by which they can be unambiguously identified. This forms the basis of a DNA profile.
Court-Admissible Test
An official DNA test in which samples are collected under controlled conditions, the identity of participants is verified, and results are issued in a form of certified documentation that is admissible before a court of law.
NIPP (Non-Invasive Prenatal Paternity Test)
The abbreviation for a paternity test performed during pregnancy using the mother's blood sample. The method analyses cell-free foetal DNA fragments (cfDNA) circulating in the mother's blood and therefore poses no risk to either the mother or the foetus — unlike amniocentesis or chorionic villus sampling. The test can be performed from the 7th week of pregnancy.
cfDNA (Cell-Free DNA)
The collective term for small DNA fragments circulating freely in the mother's blood plasma. As pregnancy progresses, approximately 10–15% of these fragments originate from the foetus. The non-invasive prenatal paternity test (NIPP) analyses this foetal cfDNA fraction and compares it with the alleged father's DNA profile.
Probability of Paternity
When the alleged father cannot be excluded, the result of a DNA paternity test is expressed as a probability value. This value is calculated on the basis of the population frequency of the tested DNA markers. In tests carried out by DNA Központ, this value is at least 99.999%, meaning the likelihood of a coincidental match falls below one in a million. This figure should not be confused with 100% certainty: DNA-based paternity confirmation is a statistical probability, not an absolute proof — however, a 100% exclusion (where the alleged father is excluded) is a mathematically exact result.
Paternity Index (PI)
A statistical indicator appearing on DNA test reports that shows how many times more likely the tested alleged father is to be the biological father of the child compared to a randomly selected, unrelated male of the same ethnic background. For example, a PI of 1,000,000 means that the tested individual is one million times more likely to be the biological father than a random man from the population. The combined PI is the product of the individual PI values calculated for each DNA marker.
Exclusion and Inclusion
The two possible outcomes of a DNA paternity test. In the case of exclusion, the alleged father's biological paternity is definitively ruled out: the DNA profiles of the child and the tested man are incompatible at two or more markers, meaning the individual tested cannot be the biological father. In the case of inclusion, the result does not exclude paternity, and the statistical probability (at least 99.999%) confirms the biological relationship.
Turnaround Time
The period of time between the laboratory's receipt of the sample and the issue of the completed report. For tests carried out by DNA Központ, this is typically 5–7 working days from the date the sample is received. Express testing may be completed more quickly; sibling testing typically takes longer (approximately 21 working days). Turnaround time does not include postal transit time.
Chain of Custody
A controlled sampling and documentation process applied to DNA tests intended for legal use, which guarantees that the sample tested unambiguously originates from the named individual and that every step of its transfer is documented. Sampling is carried out by an independent, authorised collector who verifies the identity of all parties using official documents, seals the samples in labelled containers and delivers them to the laboratory. This procedure makes the results admissible before a court, guardianship authority or other official body.
Court-Ordered / Official DNA Test
A paternity or relationship DNA test whose results can be used as evidence in official legal proceedings — including court cases, guardianship authority matters, inheritance proceedings or other official processes. This requires the chain of custody to be followed, identity to be verified, and results to be issued as a certified, signed expert report. An important distinction: the result of a private, home-sampled paternity test is not, in itself, admissible as evidence in court.
Guardianship Authority and DNA Testing
In certain circumstances — such as when establishing child maintenance obligations, in adoption proceedings, or when initiating a paternity suit — the guardianship authority (child protection authority) may order or request a DNA paternity test. In such cases, the test must comply with the requirements for official evidence, meaning it must be conducted using controlled, court-admissible sampling procedures.
STR Analysis (Short Tandem Repeat Analysis)
The methodological foundation of modern DNA paternity and relationship testing. STR analysis examines short, repetitive segments (markers) of the DNA molecule: the lengths of these segments form a unique pattern for each individual. During the test, a minimum of 21–24 such markers are compared between the child and the alleged father. The STR method is highly sensitive and specific, delivering reliable results even from small quantities of partially degraded samples.
Hair as a DNA Source
Paternity testing can be performed using hair, but only hair strands that retain a visible white bulb (hair follicle / hair matrix) at the root are suitable for this purpose. DNA is not present in the hair shaft itself but in the cells contained within the follicle. Cut, broken or shed hair without a root will in most cases not contain sufficient DNA for testing. Hair sampling is classified as a specialist sample type, is subject to higher testing costs, and there is a risk that the laboratory may be unable to extract sufficient DNA — in which case the extraction fee may still apply even if the test cannot be completed.
Special Sample
A collective term for objects and materials other than buccal swabs that contain DNA and may be used for paternity testing. Examples include: a glass or cup the person has drunk from; chewing gum; a used tissue; a toothbrush; a razor; a blood glucose test strip; a cigarette butt; or a hair strand with a root attached. Processing specialist samples incurs higher costs, results are not guaranteed (DNA content and quality vary), and the extraction fee may still apply even if testing cannot be completed. In all cases involving a specialist sample, it is strongly recommended to consult DNA Központ in advance to assess the suitability of the material.
Anonymous Paternity Test
A paternity test in which the names of the individuals tested do not appear on the report, or the order is placed anonymously. It is important to note that an anonymous test is suitable for private informational purposes only and cannot be accepted as evidence in court or official proceedings, as verification and documentation of identity is a fundamental requirement for legal admissibility. Where an anonymous test is carried out by DNA Központ, the report is issued to the person placing the order, and the result is produced to the same standard of accuracy as a named test.
Paternity Test from a Pharmacy
What is available to purchase at a pharmacy is not the DNA test itself, but the sampling kit — which contains the buccal swabs needed for sample collection, the return envelope, the unique barcode and the documentation to be completed. The actual DNA testing is performed by the accredited partner laboratory once the sample has been submitted. A kit purchased at a pharmacy enables exactly the same test as one ordered by post; the only difference lies in the method of obtaining the kit.
ISO 17025 Accreditation
An international standard that serves as independent verification of the competence, impartiality and consistent operation of testing and calibration laboratories. ISO 17025 accreditation means that the laboratory is regularly audited by an independent national accreditation body, and that its testing methodology, equipment, staff qualifications and documentation comply with international requirements. The partner laboratories of DNA Központ (AlphaBiolabs, Eurofins) hold this accreditation, which provides an independent guarantee of the reliability of all results issued.
AABB Accreditation
AABB (formerly the American Association of Blood Banks) is an internationally recognised independent organisation that accredits laboratories specialising in relationship and paternity DNA testing. AABB accreditation is particularly important in legal proceedings in the United States and other countries where submission of results from an AABB-accredited laboratory is required at an official level. The partner laboratory used by DNA Központ for NIPP testing holds AABB accreditation.
Free Paternity Test
A genuinely free, home-based DNA paternity test does not exist: the test requires accredited laboratory work, reagents and professional analysis, all of which carry a cost. What some platforms describe as a "free test" is typically a sampling kit that can be requested at no charge, with the actual testing fee payable separately — or an offer tied to other conditions (such as mandatory data sharing or a subscription). At DNA Központ, the test price includes the analysis itself, processing by an accredited laboratory and the issue of a certified report.
Child Maintenance and DNA Testing
Where paternity is legally disputed, a court may order a DNA paternity test in connection with establishing or modifying child maintenance obligations. In such cases, the test must be conducted using controlled, court-admissible sampling procedures. The result of a private home test is not, in itself, admissible as evidence in child maintenance proceedings.
Indirect Paternity Testing (Father Unavailable)
If the alleged father is unavailable or deceased, paternity may still be investigated indirectly using DNA: samples from the father's parents (grandparents), siblings or other biological relatives can be used. In such cases, the statistical certainty of the result is lower than in a direct father–child comparison, and detailed professional consultation is recommended before placing an order.
Half-Sibling and Full-Sibling Testing
DNA-based sibling testing can distinguish between a full-sibling relationship (both parents in common) and a half-sibling relationship (only one parent in common). Full siblings show a greater degree of DNA similarity than half-siblings; however, the difference requires statistical evaluation — the test does not produce a straightforward yes/no result in the same way as a direct paternity test. The reliability of the result can be improved if a sample from one of the parents is also available.
Earliest Week of Pregnancy for NIPP
The non-invasive prenatal paternity test can be performed from week 7 of pregnancy. Prior to this point, the quantity of foetal DNA fraction (cfDNA) circulating in the mother's blood is not yet sufficient for reliable analysis. Gestational age is counted from the first day of the last menstrual period. If a test is ordered before week 7, the laboratory may return the sample with a request for re-sampling.
Using Test Results Abroad
Reports issued by the partner laboratories of DNA Központ (Eurofins Medigenomix, AlphaBiolabs) originate from internationally accredited institutions, and results are therefore generally accepted in official proceedings in other countries. Depending on the legal requirements of the country in question, a certified translation or apostille authentication of the report may be required. Before using a result in a specific foreign jurisdiction, it is advisable to check the requirements with the relevant authority in that country.