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Mission
Human Life, In-Vitro Fertilization, Cloning, The Human Genome Project &
Gene Therapy and Human Embryonic Stem Cell Research
The American Bioethics Advisory Commission consists of scholars who hold academic
positions in Biochemistry, Embryology, Endocrinology, Family Medicine, Obstetrics & Gynecology,
Transplant Surgery, Pediatrics, Neonatology, Law, Philosophy, and Theology. The function of the
ABAC is to render expert opinions on bioethical issues in accordance with absolute respect for the
innate dignity and unique nature of all human beings from conception until natural death.
I. Human Developmental Embryology
- A new human life begins when a sperm fertilizes an egg forming a zygote.
- At the moment of conception, a unique genetic and personal constitution is spelled out for the
specific human being created, whose personal constitution has not occurred before and will never
occur again. The zygote is the most specialized cell under the sun in that no other cell will ever have
the same instructions in the life of the individual being created. As the zygote develops, nothing new
is learned but progressively a lot of things are forgotten. The information is written in the zygote, and
it is not written progressively in the other cells. The new findings prove differentiation and from the
very beginning there exists an embryo. As soon as he has been conceived, a man is a man (the late
Professor Jerome LeJeune, M.D., Ph.D., Rene Descartes University of Paris Faculty of Medicine).
II. In-Vitro Fertilization (IVF)
- IVF is the fertilization of an egg by a sperm in a glass dish.
- IVF is unethical, because it violates the moral right of a child to be conceived directly as a result of
his parents conjugal actions in the context of marriage.
- Due to the poor success rate of IVF, numerous human embryos are typically generated. It is
estimated that there are 100,000 frozen human embryos in storage nationwide.
- Human embryos created by IVF are human beings with the same rights as all human beings which
include the absolute right to life.
- Frozen human embryos are not "potential persons." Frozen human embryos are unique human
beings at an early stage of development whose dignity has been assaulted by freezing them in liquid
nitrogen which exposes them to grave danger if not certain death.
III. The Biology of Mammalian Cloning
The sheep Dolly was cloned by a procedure called Somatic Nuclear Cell Transplantation which was
accomplished as follows:
- Eggs were collected after ovulation had been stimulated. The nucleus of the eggs (containing
DNA) was removed from the egg.
- A mammary gland cell was placed next to the egg and an electric shock was applied causing the
egg cell to fuse with the mammary gland cell.
- This resulted in a developing embryo which was transferred to the uterus of a ewe.
- Dolly was born and DNA microsatellite analysis has confirmed that Dolly is indeed a clone.
Recently, a cow egg was fused with a human cell resulting in a hybrid organism using a similar
technique. The goal of such technology is to generate cells, tissues, and organs which are suitable for
transplantation which reduce or eliminate immunological rejection.
IV. The Human Genome Project
- Human beings normally have 46 chromosomes.
- Specific genes are located on specific chromosomes. The ultimate product of a gene is a
protein.
- The Human Genome Project is a worldwide effort to map the 100,000 genes located on human
chromosomes.
- These genetic maps will identify which genes are located on which chromosomes; the linear order
of genes on a chromosome; and the DNA nucleotide sequence of a particular gene.
- Ethical concerns arise as to who will have access to the data of a person's genome (DNA) , how
the data might be used, and possible discrimination based on genes which wither cause disease or
increase the risk of developing a disease. Also of concern is eugenics: the attempt to alter normal
genes with "desirable" or "preferential" genes which is seriously unethical.
V. Gene Therapy
- Gene therapy offers the potential to correct genetic disorders such as cystic fibrosis which is
caused by 2 homozygous recessive genes.
- Vectors are used which are methods of getting a desired gene into a cell.
- The goal in cystic fibrosis is to get the normal gene (CFTR) into airway epithelial cells and to get
the gene "turned on" or expressed without adverse consequences such as those involving the immune
system.
- In humans with CF, it has been shown that gene transfer is safe; there is evidence of getting
healthy genes into defective cells; there is some indication that the gene turns on; an in some cases,
the genes are correcting the defective CF cells.
- Using fetal mice with CF showing the same gastrointestinal abnormalities as human CF patients,
viral vectors carrying the normal CFTR gene were introduced into individual amniotic sacs where
fetuses were developing. It was shown for the first time that the lethal CF phenotype could be
completely and permanently reversed by gene therapy in utero.
VI. Human Embryonic Stem Cell Research
- Since there is a significant disparity between the number of individuals needing organ transplants
and the availability of organs for transplantation, there is enormous pressure to generate cells, tissues,
and organs for transplantation sometimes using any "means" to achieve the desired "end."
- Using the bone marrow as an example, a stem cell may divide and give rise to new stem cells or
may differentiate into various blood cells: red cells, white cells, and platelets.
- In principle, stem cells offer the possibility of differentiating into various cells lines which could be
used for transplantation in diseases such as Parkinson's, Alzheimer's, diabetes, leukemia, etc.
- One procedure to obtain stem cells for manipulation has been to remove the Inner Cell Mass from
human embryos which results in their death. This procedure is gravely unethical because it destroys a
human life. It is never ethical to use a human being as a "means" to an "end." Every human being---
including human embryos---must be respected for himself and cannot be reduced in worth to a pure
and simple instrument for the advantage of others.
- Even when death does not occur, the removal of cell(s) from a healthy embryo is seriously
unethical because it is never moral to perform experimental procedures upon human beings which are
non-therapeutic. No parent can legitimately grant moral consent for experimental procedures to be
performed upon their child which are non-therapeutic at any stage of human development.
- Totipotent cells are "uncommitted." Isolated totipotent cells are clearly human beings because
totipotency mans in fact the ability of this cell to grow into a fully formed, birth-ready human being.
- Pluripotent cells are already somewhat "committed." A pluripotent cell which can be grown into
an entire liver which can be transplanted to a human body would not be an organism itself, anymore
than we would consider a fully formed liver an organism itself.
VII. Ethical Solutions
- Placental cord blood contains stem cells that can differentiate into blood cells which could be
used, for example, in the treatment of leukemia. It is possible that these same cells might differentiate
into muscle, bone, and connective tissue cells as well.
- Recent research in early 1999 demonstrated that it was possible in beagle dogs to remove urinary
bladder cells via biopsy and grow them in the laboratory and seed them onto polymers forming new
urinary bladders for transplantation. The urinary bladder was normal and functional for up to 11
months after surgery. We encourage this research as it could be applied to human beings.
The American Bioethics Advisory Commission will continue to follow all current issues in
biomedical ethics & technology and evaluate them accordingly. Should you desire any type of
specific information or have questions or be in need of an ethical consultation, we are always ready to
assist you.
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