What we are called upon to consider regarding the acceptance of new prenatal testing methods

Opinion article by Prof. Waichiro Iwashi of Waseda University on the implementation of a new non-invasive prenatal genetic testing that uses maternal blood in Japan

Waichiro Iwashi
Professor, Faculty of Law, Waseda University

A series of reports have been released this March through April over the implementation of new prenatal testing. The first report is that on Martch 9th, five academic conferences—The Japan Society of Obstetrics and Gynecology, The Japanese Association of Medical Sciences, The Japan Medical Association, The Japan Association of Obstetricians and Gynecologists, and The Japan Society of Human Genetics—announced in a joint statement that says the implementation of these new prenatal tests should be carefully initiated as clinical research in certain medical facilities that have been approved and registered, and the Japan Society of Obstetrics and Gynecology announced guidelines for the implementation ("Guidelines regarding new prenatal genetic testing that uses maternal blood"). The latest one is that the implementation of the testing started on April 1st in three facilities throughout the country.

Prenatal testing refers to diagnosis a disease or abnormality in the fetus by obtaining information about the fetus before birth from inside the mother's body. There are some methods to achieve this end, including: diagnostic imaging using ultrasonic waves and MRI; amniocentesis, which tests fetal cells inside the amniotic fluid taken from a pregnant woman; chorionic villi sampling, performed by taking a placental villus; and maternal serum screening, performed by testing the protein concentration of blood taken from a pregnant woman. These methods differ in the type of specimen, the extent of invasiveness towards the mother's body and fetus, accuracy, and the like, as well as the content that can be diagnosed. Diagnostic imaging is mainly designed to detect external abnormalities in a fetus. Currently, however, it is widely used as a measure to check the health status of a fetus during pregnancy, rather than as a specialized test. Methods such as amniocentesis and maternal serum screening, on the other hand, are mainly designed to detect and diagnose chromosome abnormalities in a fetus when an abnormality is detected by diagnostic imaging, or in cases of late-in-life pregnancies. The new prenatal testing methods discussed here are also of this type.

A new testing method, whose guidelines have been determined at this time, is called the "new non-invasive prenatal genetic testing that uses maternal blood," and it is a method to analyze fetal DNA that exists in the mother's plasma, as well as to test for numerical abnormalities in fetal autosomes. As a method that uses maternal blood, although maternal serum screening that examines protein in the blood had already existed, this new method increased the accuracy of the tests by the use of fetus-derived DNA (the positive predictive value is considered to be 80 to 95%, while the negative predictive value is 99%). Also, it is rapid (approximately two weeks), and the invasiveness to the mother's body is far milder, as compared with amniocentesis, and the like. This method was developed and put to practical use by an American company in 2011, but there is currently no testing company that analyzes this kind of test sample in Japan, so private companies have started efforts such as mediation between medical institutions in Japan and American testing companies.

Determining any disease or abnormalities in the fetus before birth has great significance. For example, it is possible to prepare for treatment at an early stage, including before birth; and it is possible to prepare those who will become parents for having a child that might have a disease or disorder. On the other hand, the reality is that there are many cases where parents choose abortion because the range of possible fetal treatments, at present, is extremely limited. Although the Maternal Health Protection Law in Japan has not acknowledged abortion in the case of fetal abnormality, abortion due to "economic reasons" is possible (Maternal Protection Act, Article 14, Item 1), and in fact, many abortions have been performed on these grounds. Therefore, regarding prenatal diagnosis in general, the opinion to seek a cautious approach has traditionally been strong, from the viewpoint of protecting the life of a fetus.

There is also a strong awareness of this point in the guidelines, which specify that prenatal testing should only be practiced in limited facilities that can provide sufficient genetic counseling, and also provide the details of the requirements for facilities, standards regarding pregnant women who are the targeted patients, content of the genetic counseling, and the like. While such a careful approach attracted some positive responses, regarding the fact that these guidelines name the numerical chromosome aberrations of chromosomes 13, 18, and 21, and they were prepared as guidelines to test and detect those aberrations, The Japan Down Syndrome Society has expressed a concern that a misperception that it is unfortunate to be someone with Down Syndrome is likely to be formed.

The implementation of this new prenatal testing has already been discussed from various angles, such as in the reports mentioned above, so I probably do not need to repeat it. I would like to say, however, that the acceptance of the implementation of new prenatal testing requires us to be prepared to accept those who have diseases and disorders due to genetic causes, and to support them and their families. No matter how much the guidelines require the implementation of thorough genetic counseling, the decision whether to give birth based on the diagnosis is ultimately up to the pregnant woman (and her husband). As a result, easy self-responsibility theory, which says those who decided to give birth should be responsible for the child who was born, or those who decided on abortion should accept the burden of emotional distress caused by selecting abortion—because the woman herself decided to do so after thorough counseling—might be raised.

The important thing is the attitude to understand the disease, condition, or genotype based on genetic changes as being part of human diversity and to respect such diversity and uniqueness (Statement of the Japan Society of Obstetrics and Gynecology as of September 1, 2012). We should keep in mind that as a society to accept these guidelines, which intend to perform sufficient counseling, including explanations of the placement of tests and the meaning of having a disorder, means that it respects the decision made by the person after counseling and continues to support the life that was born.


Waichiro Iwashi
Professor, Faculty of Law, Waseda University


Courses: Civil Code III, Clinical Legal Education (Housework/Gender) I & II, Life Science and Law, Medical Law I
Alma mater, etc.: Faculty of Law, Waseda University; Graduate School of Law, Waseda University
Main background/overseas research, etc.: Visiting Scholar, Ludwig Maximilian University of Munich
Main research/practical theme: Civil Code; Medical law; Law of Germany
Main books, thesis, etc.:
(*Coauthored or edited books included)
Key Words of the Civil Codes [Mimpo Kiwado] (Yuhikaku Publishing)
Fundamental Law Commentary, 4th Ed., Kinship [Kihonho Konmentaru Dai 4 Han, Shinzoku] (Nippon Hyoron Sha)
Modern Medicine Spectrum, Forum Medical Law II [Gendai Iryo no Supekutoru, Foramu Iji Hougaku] (Shogakusha)
Family Law/Inheritance Laws [Shinzokuho/Sozokuho] (Shogakusha)
Lecture Note of the Inheritance Laws [Sozokuho Kogi Noto] (Seibundo Publishing) etc.

Published: 08 May 2013


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