Prenatal paternity testing from semen.

Methods of DNA extraction from condom semen.

1. Sample collection:.

Semen is carefully collected from used condoms. Sample handling at this stage is very important as semen contains male genetic information. Try to collect as much semen as possible and place it in a clean container to avoid contamination.

2. Cell degradation:.

Collected semen contains a large number of sperm. Enzymes such as proteinase K are used to break down the sperm cell membranes and extract the DNA inside. At this stage, processing is often carried out in a temperature-controlled incubator, which allows DNA to be extracted efficiently.

3. DNA purification:

After DNA is extracted from semen, DNA purification is performed to remove other cellular components and impurities. Typically, phenol-chloroform extraction or silica column purification methods are used. This yields pure DNA, which is then used for subsequent analysis.

4. PCR amplification:

If the DNA sample obtained is small, the DNA is amplified using the polymerase chain reaction ( PCR); PCR is an important technique for replicating a particular DNA region thousands of times to ensure the required quantity for analysis.

5. DNA analysis:.

Amplified DNA is used for genetic analysis and DNA profiling. This involves analyzing the DNA pattern of a particular individual, confirming parent-child relationships and personal identification. In forensic science, semen DNA is often used in criminal investigations and plays an important role as evidence.

Relationship with prenatal paternity testing.

Prenatal paternity testing is carried out while the fetus is still inside the mother’s body in order to establish the parent-child relationship with the prospective father. DNA extraction from condoms and prenatal paternity testing have several similarities and differences.

Common denominators:.

  • Both methods use DNA to confirm parent-child relationships. DNA extracted from the semen contains the genetic information of the potential father, which is compared with the fetus’ DNA to confirm the parent-child relationship.
  • Both share the use of PCR amplification techniques to increase the amount of DNA and ensure sufficient sample volume for analysis.

Differences:.

  • The samples used differ. In DNA extraction from condoms, semen is used as a sample from which DNA is extracted. Prenatal paternity testing, on the other hand, requires the DNA of the fetus. This DNA is obtained from the mother’s blood, amniotic fluid and chorionic villi.
  • While DNA extraction from condoms is primarily used to obtain genetic information on adult males, prenatal paternity testing focuses on early confirmation of parent-child relationships during the foetal period.

The method of obtaining foetal DNA from the mother is particularly important in prenatal paternity testing. As foetal DNA is found in trace amounts in the mother’s blood, non-invasive prenatal genetic testing (NIPT) can be used to analyze the DNA without risk to the mother or fetus.

Conclusion

DNA extraction from condoms is an important technique in forensic evidence collection and personal identification. It can thereby play an important role in confirming parent-child relationships and in criminal investigations. Prenatal paternity testing, on the other hand, is a means of confirming parent-child relationships during the foetal period, and non-invasive NIPPT is becoming the norm. Both technologies are based on accurate analysis of DNA and are expected to evolve further in the future. There is a need to understand the impact of these technologies on society and the need to maintain a balance between science and ethics in their development. HIRO Clinic offers DNA collection from toothbrushes. Please note that this costs an additional JPY 33,000.

Supervisor of the article


Dr. Hiroshi Oka

Director of CAP Laboratory

Graduated from Keio University, Faculty of Medicine

Doctor of Medicine

Medical Doctor