Eubios Journal of Asian and International Bioethics - Eubios Ethics ...

12 Eubios Journal of Asian and International Bioethics 22 (January 2012)
chromosomal disorders (C. genetic/chromosomal
diagnosis). Finally, inseminated egg cells without genetic
diseases or chromosomal disorders are produced outside
the body and then transferred to the uterus (A. IVF-ET).
For the implementation of above C, the following three
diagnostics can be used.
Genetic disease diagnosis – in this case, genetic
amplification (polymerase chain reaction, PCR) is the
molecular biological technique utilized for the detection of
genetic mutations in a single genetic disease.
Pre-implantation genetic screening (PGS) – in this
case, fluorescence in situ hybridization (FISH), and
recently array CGH, are the molecular biological
techniques most frequently applied for the detection of
chromosomal disorders (structural and numerical).
Sex diagnosis – in this case, besides FISH, PCR
and cell recycling are the molecular biological techniques
applied for sex determination.
In short, embryo biopsy PGD 10 entails PGD of
inseminated egg cells by means of PCR, FISH and CGH.
3. Is embryo biopsy PGD the selection of life?
(a) Is the Japan Society of Obstetrics and
Gynecology (below, JSOG) endorsed embryo biopsy
PGD for the purpose of preventing “habitual
miscarriage (including recurrent miscarriage)
thought to be caused by structural chromosomal
disorders” actually the selection of life?
Some members of handicapped persons’ groups and
the mass communication community are criticizing
embryo biopsy PGD as a precaution against “habitual
miscarriage (including recurrent miscarriage) thought to
be caused by structural chromosomal disorders” to be,
from an ethical point of view, the selection of life.
As stated above, in embryo biopsy PGD, the first 1 or 2
blastomeres are taken from a 2 to 3 day old embryo (B.
embryo biopsy), or several chorionic cells are taken from
the blastocyst, followed by the examination for genetic
mutations and chromosomal disorders (C.
genetic/chromosomal diagnosis). Finally, inseminated
egg cells without genetic diseases or chromosomal
disorders are transferred to the uterus (A. in vitro
fertilization and embryo transfer (IVF-ET)). Those arguing
against PGD criticize this selection of inseminated egg
cells as the selection of life.
The people criticizing embryo biopsy PGD aimed at
preventing “habitual miscarriage (including recurrent
miscarriage) thought to be caused by structural
chromosomal disorders”, judge this to be a selection that
attaches qualitative differences to life. However, this is a
10 In recent years, Whole Genome Amplification (WGA) has
frequently been used as a treatment method in the event of
implementation of inseminated egg cell PGD and polar body
PGD. WGA is a DNA amplification method for which PCR, FISH
and CGH can be used, equally amplifying a minimum of the
DNA contained in inseminated egg cells and polar bodies
across the whole genome. A task force at Keio University
estimated that WGA is ‘a first step in the new era of
PGD/PGS’(T Sato, K Matsuoka, A Nakabayashi, Y Yoshimura :
Preimplantation Genetic Diagnosis by whole genome
amplification, PGD of the New Era, making a swift and easy
genome-wide numerical duplication analysis possible, The
Practice of Obstetrics and Gynecology 59 (4), Kanehara
Publishing, 2010
mistaken judgment. In the first place, in the case of
structural chromosomal disorder patients, inseminated
egg cells with structural chromosomal disorders are of
frequent occurrence. And inseminated egg cells with
structural chromosomal disorders either do not become
implanted in the uterus, or abort even when implantation
does occur. There are cases where this natural screening
process in the womb is sidestepped and pregnancy
occurs, but the number of such cases is extremely small.
Therefore, embryo biopsy PGD for patients suffering from
“habitual miscarriage (including recurrent miscarriage)
thought to be caused by structural chromosomal
disorders” is a selective relief action for the precious few
inseminated egg cells that are able to be saved and
should not be considered the selection of life.
(b) Is the JSOG non-endorsed embryo biopsy PGD
aimed at preventing “miscarriage thought to be
caused by numerical chromosomal disorders”
actually the selection of life?
There exists criticism that if the current JSOG nonendorsed
embryo biopsy PGD for the purpose of
preventing “miscarriage thought to be caused by
numerical chromosomal disorders” (for example, avoiding
Down’s syndrome’s trisomy-21) should come to be
implemented in future, that it would mean that a selection
attaching qualitative differences to life would occur. There
is some truth behind this criticism, but it is an unyielding
fact that the natural screening process inside the uterus
causes 80% of trisomy-21 to abort, and that an even
higher percentage of other kinds of trisomy (besides X, Y,
13, 18, 21, 100%) abort. Based on this fact, the current
JSOG non-endorsed embryo biopsy PGD for the
prevention of “miscarriage thought to be caused by
numerical chromosomal disorders” is a selective relief
action for the precious few inseminated egg cells that are
able to be saved and should not be considered the
selection of life.
In considering the above questions, it is necessary to
reconsider the origins of life and the definition of the
quality of life. My personal opinion is that the origins of
life lie at a time two weeks past insemination when the
primitive streak is formed in the embryo. However,
according to Anne McLaren, life begins at the moment of
insemination. Nevertheless, although it’s the same life,
there are undeniable differences in the dignity of life
within the period from insemination of the egg cell to the
birth of the human being. Both the existing laws and
social common sense have more respect for a born
human being than an unborn child, and more respect for
an unborn child than an inseminated egg cell. As proof of
this fact, in the real world memorial services are held for
miscarried/aborted fetuses, but none are held for
inseminated egg cells. However, embryo human rights
protagonists claim that, from inseminated egg cells to
born human beings, all life is qualitatively equal and
should be treated the same. If they are claiming though,
as the Vatican does, that the disposal of “frozen
redundant embryos” is “mass murder”, then these
embryo human rights protagonists should urgently lecture
on improvement measures against the current situation
of induced abortion, in which every year millions of
embryos are “massacred”. Also, since the contraceptive