Postnatal DNA Testing

Reasons for Conducting Postnatal DNA Testing

Legal Reasons
In cases such as inheritance, asset division, or succession, it may be necessary to confirm whether the individual believed to be one’s child has indeed inherited their DNA.
The primary concern in these cases is often financial.

Psychological Reasons
Even if individuals have been told they are parent and child or siblings, they may wish to confirm the biological relationship.
It may also be used to rule out the possibility of a spouse’s infidelity.

Accidental Exchange with Others
In situations where there is suspicion of a child being switched at birth or during artificial insemination due to sample mix-ups, postnatal DNA testing can be used to verify identity.

Paternity Testing

Postnatal paternity testing is a DNA test conducted to determine whether an individual has a specific parent-child relationship.
This test analyzes specific regions of DNA (commonly STR regions) to assess whether the tested individuals (parent and child, or either one) are genetically related.
Since the child inherits half of their genetic material from each parent, comparison based on these genetic characteristics allows for a highly accurate determination of parentage.
Usually, either the father or the mother is tested, making it the most direct method for confirming biological relationships.

Samples must be collected from both the parent and the child — two individuals in total.

Sibling Testing

Postnatal sibling testing is a DNA test conducted to determine whether two individuals share the same biological parents.
Compared to paternity testing, sibling testing is slightly more complex and generally has a lower level of precision.
It involves comparing the DNA of the individuals and assessing the degree of similarity in shared genetic markers (typically STR regions) to estimate the likelihood that they have the same biological parents.

In sibling testing, the absence of the parents’ DNA information can sometimes limit the amount of genetic data available, meaning that the results may involve some degree of inference rather than absolute proof.
Nevertheless, sibling testing remains an effective method for estimating the probability of a shared parentage.

Samples must be collected from the two siblings and the common parent — three individuals in total.
DNA is typically collected from buccal swabs or other available biological materials.

Method

Postnatal paternity testing primarily involves collecting cells from the oral mucosa (inside of the cheek) for DNA analysis.
This method determines parentage by comparing the DNA profiles of the parent and child to verify matching genetic patterns.

In addition to buccal swabs, other samples containing DNA — such as blood or hair — can also be used.
The testing process employs highly advanced techniques, ensuring high reliability. Therefore, results can be used not only for personal confirmation but also for legal purposes, inheritance claims, and immigration procedures.

The STR (Short Tandem Repeats) analysis used in paternity testing examines specific regions of DNA where short sequences of base pairs (typically 2–6 base pairs) are repeated.
Because the number of repeats at these locations varies between individuals, comparing the STR patterns of the parent and child enables confirmation of their biological relationship.

Specifically, between 23 and 52 STR loci are typically analyzed.
Since a child inherits half of their DNA from each parent, the matching STR patterns provide strong evidence of parentage.

Why Is STR Analysis Used?

• High Reliability:
  Because STR patterns vary between individuals, they are extremely suitable for determining biological relationships such as parentage.
• Convenience:
  STR analysis requires only a small amount of DNA and can easily extract DNA from samples like buccal swabs, blood, or hair.
• Legal Proof:
  Due to its high reliability, STR analysis is recognized in many countries for use in legal documentation of parent-child relationships.

This method is not only used for parentage testing but also for determining other familial relationships, such as grandparent–grandchild or sibling relationships.

Results

High Accuracy: If a parent-child relationship exists, a match is confirmed with over 99.99% probability. If no parent-child relationship exists, it is ruled out with over 99.99% probability.

Test reports are typically returned within an average of 5.5 days.

Use Cases

Legal:
Custody disputes and child support determinations.

Personal:
Confirming family relationships and understanding genetic risks.

Such testing is highly reliable and can be used as evidence in court.

Under a physician’s supervision, it is also possible to conduct a legal test.

If you wish to request a paternity test, please contact us.

Test results are typically provided by email within an average of 5.5 days.

In the case of legal testing, a document with the physician’s handwritten signature will be mailed to you after the test report is sent by email.

Fees