Why is DNA prenatal paternity testing getting so much attention?

親子鑑定 NIPPT DNA鑑定 注目 なぜ 

Summary of this article

In recent years, interest in DNA prenatal paternity testing (DNA Prenatal Paternity Test: Non-Invasive Prenatal Paternity Test) has grown rapidly. Unlike conventional postnatal paternity testing, DNA prenatal paternity testing has many advantages because it can establish paternity from mid-pregnancy. In this article, we will explore why this technology is important to so many people, including an overview of DNA prenatal paternity testing, why it is gaining so much attention, and an explanation of some of the technical terms used.

Outline of DNA Prenatal Parentage Test

DNA prenatal paternity testing is characterized by its non-invasive nature and extremely low risk to the fetus. Conventional amniotic fluid and chorionic villus tests are invasive and carry a risk of miscarriage, making DNA prenatal paternity testing an ideal option for many pregnant women who wish to avoid the risks. The mother’s blood contains free fetal-derived DNA (cfDNA), which can be analyzed to determine the genetic information of the fetus.

Why DNA prenatal testing is attracting attention

2.1 Non-invasive and safe

Traditional methods of paternity testing require invasive methods to directly obtain fetal genes. These include amniotic fluid testing, in which amniotic fluid is extracted from the mother’s abdomen, and chorionic villus testing, in which villi are extracted from the placenta. DNA prenatal paternity testing avoids these risks because it extracts fetal DNA from the mother’s blood.

2.2 Early confirmation of parent-child relationship

DNA prenatal paternity testing can be performed after the 10th week of pregnancy, allowing for early confirmation of parent-child relationships. This allows for early planning regarding future legal procedures and family relationships. This is a particularly valuable technique for couples who wish to establish the parent-child relationship early in order to avoid confusion and anxiety within the family.

2.3 Improved accuracy

The accuracy of DNA prenatal testing has improved significantly due to advances in technology. Modern DNA prenatal testing determines paternity with high accuracy by analyzing specific DNA polymorphisms called SNPs (Single Nucleotide Polymorphisms) and comparing alleles between the fetus and the prospective father. SNPs are polymorphisms that occur when one base in a gene is replaced by another base, and are an important factor in determining an individual’s genetic characteristics.

2.4 Multiple Pregnancies and Vanishing Twins

In the case of multiple pregnancies, the results obtained by DNA prenatal paternity testing should be treated with caution. A phenomenon called Vanishing Twin may occur. This is a phenomenon in which one of the twins or multiples disappears early in pregnancy, which may affect the genetic analysis of the remaining fetus. When vanishing twins occur, there may be residual cfDNA of the vanished fetus in the mother’s blood, which may affect the results of the parent-child test. Therefore, careful judgment is required in cases of multiple pregnancies.

Technical Aspects of DNA Prenatal Parentage Testing

3.1 DNA polymorphisms and SNPs

A DNA polymorphism refers to several different alleles in the genome; SNP counts are used to indicate differences in these alleles. in DNA prenatal paternity testing, the DNA polymorphisms of the fetus and the potential father are compared and the number of matching SNPs is analyzed to confirm the paternity relationship.It is particularly important to identify how alleles inherited from the father are inherited by the fetus.

3.2 HLA Type and Genome Analysis

HLA type (Human Leukocyte Antigen) is a gene associated with the immune system and plays an important role in determining an individual’s immune response. As part of DNA prenatal paternity testing, HLA type analysis may be performed. This allows for a more detailed confirmation of the parent-child relationship by determining whether a particular genetic trait is present. The entire genome is also analyzed to detect specific insertion-deletion polymorphisms (Indel Polymorphisms), allowing for even more accurate parent-child identification.

3.3 Indel Polymorphisms are inserted

Insertion-deletion polymorphisms are mutations in which a short segment of DNA is inserted or deleted at a specific position in the genome. These polymorphisms may be used to identify genetic differences between individuals and are useful in DNA prenatal paternity testing. When comparing the genomes of the fetus and the prospective father, these insertion-deletion polymorphisms can be identified to more reliably determine the parent-child relationship.

Status of use and legal aspects of DNA prenatal testing4. status of use and legal aspects of DNA prenatal testing

4.1 Usage in Japan

In Japan, DNA prenatal paternity testing is gradually becoming more widespread, but its use still requires a cautious approach. It is important to seek accurate results because the results obtained from DNA prenatal testing can be used as evidence in a court of law.

4.2 Legal Procedure and Determination of Parent-Child Relationship

In Japan, a paternity test is generally conducted after birth in order to legally determine parent-child relationships. However, there is a movement to determine the parent-child relationship before birth based on the results of a DNA prenatal paternity test.This protects the welfare and future rights of the child, while also allowing legal proceedings to proceed when the parent-child relationship is established.

The future of DNA prenatal parentage testing5. the future of DNA prenatal parentage testing

DNA prenatal paternity testing is expected to further improve in accuracy and be used by more people in the future. In addition, advances in genome analysis technology will enable more detailed genetic information to be obtained, which may be applied not only to the determination of parent-child relationships but also to risk assessment of genetic diseases. This will make DNA prenatal paternity testing an important part of future family planning and health care.

6. Summary

DNA prenatal paternity testing (NIPPT) is a revolutionary technology for non-invasive and safe early confirmation of parent-child relationships, utilizing the latest genetic analysis technologies, including SNP counts, alleles, DNA polymorphisms, HLA types, and insertion-deletion polymorphisms, to determine parent-child relationships with high accuracy.The technology is flexible enough to handle complex cases such as multiple pregnancies and vanishing twins, and takes into account legal procedures and ethical aspects.With the further development of DNA prenatal parentage testing, more and more people will be able to utilize this technology to establish parent-child relationships with confidence.

Supervisor of the article


Dr. Hiroshi Oka

Director of CAP Laboratory

Graduated from Keio University, Faculty of Medicine

Doctor of Medicine

Medical Doctor