[Congressional Record Volume 151, Number 74 (Tuesday, June 7, 2005)]
[House]
[Pages H4179-H4184]
From the Congressional Record Online through the Government Publishing Office [www.gpo.gov]
STEM CELL RESEARCH
The SPEAKER pro tempore. Under the Speaker's announced policy of
January 4, 2005, the gentleman from Maryland (Mr. Bartlett) is
recognized for 60 minutes.
Mr. BARTLETT of Maryland. Mr. Speaker, a couple of weeks ago on this
floor there was a very prolonged and serious debate on stem cells. Now
that we have had time for emotions to subside, I thought it might be
productive to spend a little while this evening talking about the
subject of stem cells and why there is so much interest in it across
the country.
A few months ago there was so much interest in this subject in
California, for instance, that the voters voted favorably for a
resolution that would make $3 billion from California taxpayers
available to do research on embryonic stem cells.
What are stem cells? We have a chart here which kind of shows this.
{time} 2215
There are fundamentally two types of stem cells. There are adult stem
cells and there are embryonic stem cells.
I guess the ultimate stem cell is the fertilized ovum, which is
referred to here as a zygote, because from that cell develops all the
cells of the body. That single cell, produced from the union of the egg
and the sperm, divides and divides again and again until finally it is
a blastocyst; and then it goes to the gastrula stage, and at that stage
the three germ layers begin to sort out the cells that are already
differentiating, is the technical term that is used for that.
Every cell in our body, of course, has all of the same gene
complement. And by mechanisms that are not clearly understood, during
the embryonic process genes get turned on and get turned off, and the
cells that are destined to produce your skin, for instance, the genes
that are producing all the other tissues of the body are turned off,
and only those genes necessary for producing the skin are still active.
Here we have the three germ layers: The ectoderm, which is the outer
layer, and from that will develop your skin and your nervous system.
Then we have the mesoderm, that will be the middle layer, meso
meaning middle, and from that will develop most of the weight of your
body, all of your skeletal muscle, your cardiac muscle, much of the
kidney, the blood cells, the smooth muscle in your intestines and
stomach and so forth.
Then from the innermost layer of this inner cell mass as it is called
here, the mass of cells that differentiates into these three germ
layers, the endoderm, the internal layer, produces not very much of the
mass of your body, the pancreatic cell and the thyroid gland and the
line of the things like your lung and intestines and so forth are
produced from the endoderm.
Then, of course, there are the unique germ cells produced, the sperm
in the male and the egg or the ova in the female.
The reason for the intense interest in these stem cells is because of
the perceived potential for affecting the course of many diseases and
hopefully curing many of our diseases.
We have fundamentally two kinds of problems with our health. One is
from tissue deficiencies when the tissue no longer does the kind of
thing that it was destined to do and this embryonic development is
wearing out or diseased. Then we have diseases from pathogens. These
are organisms that can be outside that invade us.
Primarily, the hope is that stem cells will be useful in treating
diseases of tissue deficiency. Although if the pathogens have destroyed
a tissue and then the body has marshaled its resources with the help of
the doctors with the antibiotics and so forth so that the pathogen is
destroyed, then there is some hope that through the use of stem cells
that you might be able to repair or replace the tissue damaged by the
pathogen.
There are a lot of examples of diseases that might be amenable to
cure or at least assistance through these stem cells. One is diabetes,
which is a deficiency of insulin. Insulin is produced by some little
cells that look like islands under the microscope because they are very
dissimilar to the cells that they find themselves in. These cells are
distributed through the tissue of the pancreas.
The pancreas is a big gland that produces a lot of enzymes. When the
food leaves the stomach and goes into the small intestine, the pancreas
produces enzymes for the digestion of fats, carbohydrates and proteins.
So it is a very important digestive gland.
There is no real reason why these little islands of tissues, called
the islets of Langerhans, named for the person who first described
them, need to be in the pancreas, but that is where they are. They
could, in fact, be any part of your body and do the same thing, which
is secreting insulin.
We use insulin to treat persons with diabetes, but everyone knows,
particularly the family of those and the patients who have diabetes,
that insulin does not cure the disease. It simply prolongs life, but,
ultimately, even with insulin, many of the people who have diabetes
will end up having peripheral vascular problems with maybe amputation
of toes or limbs, usually the lower limb, have problems in the eyes
with the peripheral vascular there in the eyes and have vision
problems.
Diabetes is the most expensive disease that we have. It costs more to
[[Page H4180]]
maintain and treat the people with diabetes than any other disease.
There is the hope that if we could generate islets of Langerhans cells
from these stem cells that you could eradicate diabetes, that you could
implant these cells in the body, and it could be in any tissue. It
could be in muscle tissue or under the skin. You could implant these
islets of Langerhans cells there that produce insulin and whatever else
these cells do that is not done simply by replacing the insulin which
is lost. We might be able to eradicate diabetes, which, of course,
would be an enormous contribution.
This is one of the most heart-wrenching things that the congressmen
see, is when these little kids come to your office, they have to prick
their finger maybe a dozen times a day, and they need insulin so
frequently that they have an embedded little pump under their skin,
about the size of a hockey puck. They may have to wake up during the
night and prick their finger so that they can set the pump so it
produces the right amount of insulin.
This is just one of many diseases that authorities in medicine and
the general public believes might be helped with stem cell research:
multiple sclerosis, lateral sclerosis, Lou Gehrig's disease.
That is one that I am personally very familiar with. My grandmother
died from that disease. This was a long time ago, and it took quite a
long time to diagnose that disease. She was falling. For quite a while
they did not know why, and finally they diagnosed it as Lou Gehrig's
disease, as was the common name for it then. I remember watching my
grandmother deteriorate until the only motion that she had left, that
she could communicate with us, was blinking her eyes: once for yes and
two for no. Then she slowly died when she could no longer eat or drink.
She did not want to be force fed.
We did not have any dream then of stem cells and what they might do
for that disease, but I can understand the hope that families have who
have a loved one who has a disease like this and the hope that they
have that there may be a medical advance and a miracle cure for the
disease.
Alzheimer's disease, my mother had Alzheimer's disease. How nice it
would have been to have turned back the clock in her mind so that she
was the mother that I spent the first 60 years with.
Then, of course, there is a very large category of autoimmune
diseases. I have a list here of 63 autoimmune diseases. That is an
interesting type of disease. When we are developing in our mother's
womb very early and our heart is beating and we have a circulatory
system and we have white cells, there is a particular kind of white
cell called the T cells. Very early in our embryonic development those
T cells are imprinted with who we are, and that is very necessary
because they have to understand who we are, who you are, who I am, so
that if some foreign invader comes in there or virus or bacterium or
something, they recognize that as being foreign so that they can reject
it.
For reasons that we do not understand, occasionally our autoimmune
mechanisms get confused, and they see some of us as not being us, as
being foreign, and so they attack it. We call those autoimmune
diseases, and there are a lot of those autoimmune diseases: Addison's
disease, autoimmune hemolytic anemia, autoimmune hepatitis. It goes on
for 63 of these diseases.
Multiple sclerosis is one of those, by the way. Lupus was one of the
first of these diseases that was identified as an autoimmune disease.
There is a hope that stem cells could be useful in treating all of
these diseases.
Then, of course, there are the injuries of central nervous tissue. We
have two kinds of nervous tissue in our body, the central nervous
tissue that is in our brain and spinal cord and then the peripheral
nerves. That is the nerves that run to and from the brain and spinal
cord. For reasons that is difficult to understand, they have two very
different responses to injury.
Peripheral nerves regrow very easily. There is a classic phenomenon
known as Wallerian degeneration and then regeneration of the nerve. If
you cut a nerve well up in your leg that goes to your toe, it may be a
long while before you get feeling back to your toe, almost always,
unless a lot of scar tissue develops where the nerve was cut.
But for some reason that we do not yet understand central nervous
tissue has no power to regenerate. Of course, what we are trying to do
medically is to find out why central nervous tissue is different than
peripheral nervous tissue, but absent finding out why so that you can
turn that around there is the hope that with these stem cells we could
grow nerve tissue that could then be placed in the body, injected in
the body to help repair.
So there are a lot of diseases out there that medical specialists and
the public generally believe could be cured or at least the course of
the disease quite favorably changed with the use of stem cell
technology.
There are, of course, two kinds of stem cells: embryonic stem cells
and adult stem cells. Most of the work that we have done so far is with
adult stem cells because we have been working with them for over three
decades. We have been working with embryonic stem cells just a little
over 6 years, and so the techniques for using adult stem cells are far
better developed.
So there are more medical applications from adult stem cells than
there are from embryonic stem cells, but we have not had enough time
working with embryonic stem cells to determine whether or not they have
the increased potential that most people believe they should have. The
medical specialists believe this. The general public understands this.
If you are dealing with a cell that is not differentiated, that is,
that it has not developed far enough along so that genes are turned
off, a lot of leads are turned off, it could then develop into anything
and everything with proper manipulation in the laboratory. So that if
you are using embryonic stem cells there is the hope that they should
have a wider application than adult stem cells.
{time} 2230
There is another interesting characteristic of embryonic stem cells,
and I do not know how important it will be. Only research will
determine that.
At least 50 years ago, embryologists had determined that you could
take a mother white mouse and a mother black mouse, each of which was
pregnant and they have multiple babies in their uterus, and you could
go into the uterus of the black mouse and take a little patch of skin
out of the black mice, you could sew it into the skin of one of the
white mice. When the white mouse is born, it has a little patch of
black skin. Quite amazingly, it is not rejected.
Everybody knows when you transplant an organ from one person to
another, there is a big rejection reaction to that. So we have a lot of
anti-rejection drugs that we give. The person who gets that organ
transplant must take those anti-rejection drugs. As soon as they stop
taking them, the T-cells recognize this thing as foreign and start to
attack it. Its use in the body is destroyed.
I do not know whether this little mouse experiment, whether the
miracle of no rejection is a donor phenomenon or host phenomenon; but
when you take skin from one embryo to another, there is no rejection.
So using embryo stem cells, they might be less rejected. That would be
good news.
I would like to spend just a couple of moments reflecting on some of
the elements of a debate here in this Chamber. These debates are a bit
like a battle. They are a battle; you are fighting for your position.
Like all battles, emotions rise and sometimes things are exaggerated a
little by one side or another. Now that emotions have subsided and we
are dealing with other issues, I thought it might be instructive to
look at some of the arguments made on both sides.
The argument on the pro-life side was that life is sacred, that these
little embryos are human life, and the President has a position which I
very strongly support, that it is just morally wrong to take one life
hoping you can help another life. There has got to be another way to do
it.
The bill we were debating said we should take some of those 400,000
surplus embryos that were produced in the in vitro fertilization
clinics that were going to be discarded anyhow, we should take those
embryos and use them to produce embryonic stem cell lines. For the last
4 years we have been dealing with what started out as maybe 60 cell
lines, which has now
[[Page H4181]]
dwindled down to 22, all of them contaminated with mouse feeder cells
so they are only good for research. They would not be good for medical
use so there is a need for additional embryo stem cell lines. These are
the only stem cell lines we can use Federal money exploring. The
private sector can destroy all of the embryos they wish; there is no
prohibition. You just cannot use Federal money so there are only 22
cell lines we can use Federal money to explore.
The argument on the pro-life side, and I subscribe to that argument,
that for any one embryo, there is no certainty that embryo is going to
be destroyed, that it is going to be abandoned. The argument on the
other side is there are 400,000 of them. Of course they are, you cannot
keep them frozen forever, and by and by they will be discarded. But not
all of them, because we now have, I understand, over 100 babies who
have been born from adoption of these snowflake embryos.
We have surplus embryos because when you go for in vitro
fertilization, under hormone stimulation the mother produces more than
one ovum; and they are put in a petri dish and exposed to sperm and
fertilized. Then the doctor watches their growth, and the doctor
chooses generally several because they do not all adhere to the uterus
and grow to become babies, and so he wants to be sure there will be at
least a baby. So he implants several in the uterus, and there are
several left over that are then frozen in the event none of those take
or the mother wants to have a baby later.
I remember when I was running a farm several years ago, I was
breeding cattle to a bull that had been dead for 8 years. I do not know
how long the sperm and the ovum or these embryos will survive frozen,
but they will survive for quite a long time.
The argument on the pro-life side is that for any one of those
embryos, it could be adopted; and that is true. If you have a reverence
for life, as I do, you need to find another way to pursue embryonic
stem cell research without destroying embryos, and we have a bill that
does just that. We have talked to experts from NIH and others around
the country, and in a few moments I will be talking about that bill.
One of the arguments made by the pro-life people is we have had 58
medical applications from adult stem cells and none from embryonic stem
cells, and that is true. But as Paul Harvey would say, the rest of the
story is maybe the reason it is true because we have spent 3 decades
working with adult stem cells and only about 6 years working with
embryonic stem cells, and you will not know if they have the same
potential until you have an equivalent amount of time to work with
them.
The arguments on the other side were that these cells are going to be
thrown away anyhow and why not get some use from them. I have just
reiterated my argument, which is the argument of the pro-life
community, which is for any one of those embryos, they could be
adopted. In fact, some of these snowflake babies came to the White
House during this debate, so they can be adopted.
There was another bill that we voted on that night and that was the
umbilical cord blood bill which many mothers are now having frozen
because there are some stem cell-like cells there that might be useful.
But the argument is although they might be useful, they would not be as
useful as the embryonic stem cells themselves.
``As a physician-scientist,'' and this is a direct quote from Curt
Civin, co-director, Division of Immunology and Hematopoiesis Sydney
Kimmel Comprehensive Cancer Center, one of the centers at John Hopkins
University School of Medicine, and we are fortunate in our State to
have one of the best universities and one of the best medical schools
in the world, that is Johns Hopkins, he says, ``As a physician-
scientist who has done research involving umbilical blood cord stem
cells for over 20 years, I am frequently surprised by the thought from
nonscientists that cord blood stem cells may provide an alternative to
embryonic stem cells for research. This is simply wrong,'' he says.
By the way, all of the 58 diseases that have had applications from
adult stem cells, all of them are represented by organizations that
support embryonic stem cell research because the general belief is
there ought to be more potential from embryonic stem cells than from
adult stem cells.
Just a little history why I am standing here this evening and how I
got involved in this. I did not come to this Congress until, and this
was 13 years ago, until I was 66 years old, and so I had a former life.
In that former life, I was a scientist. I have a Ph.D. in human
physiology. I taught medical school and postgraduate medicine and spent
a number of years doing research at medical schools and at the National
Institutes of Health.
Several years ago, in 2001, I believe it was, there was a little like
symposium at the National Institutes of Health where staff and members
went out. I went out with a fairly large number of staff members where
the experts from NIH were briefing the staff and members who were there
on stem cell research. This was just before the President came down
with his executive order on stem cells, and this was kind of an
educational activity on the part of NIH. There were several researchers
there; and as we can see in the next chart, I suggested it ought to be
possible to take cells from an early embryo without hurting the embryo
and that was because of my knowledge of what happens in twinning.
Now, the first chart here shows the usual type of twinning. That is
where you have two zygotes. That is the mother sloughed two ovum, not
just one, and both were fertilized and both came down and were
implanted in the uterus and they grew two fetuses, and they are called
womb mates because they share the womb.
Well, we also can have twins, and the next chart shows identical
twins and what happens with identical twins.
This can occur apparently in at least two different stages in the
development of the embryo. Here we have the zygote, which is the union
of the egg and the sperm, and that then divides to two cells; and they
have left out a lot of stages here because there is a lot of stages
between the two cell and the inner mass cell stage.
These embryos can split at the two-cell stage or later on when they
grow two inner cell masses. You can tell at what time they split by how
they present themselves. If they are presented in two placenta, they
split early and they go their separate ways. If they split later, they
are generally presented at birth in a single placenta so the doctor
knows the approximate time they split.
I recognized what was really happening here was in a sense you were
taking half of the cells away from the original embryo, and both halves
went on to produce a perfectly normal baby. So it seemed perfectly
logical to me that you ought to be able to take a cell or two from an
early embryo without hurting the embryo. There has been a lot of
research since that.
By the way, the experts at NIH said, yes, that should be feasible. I
mentioned this to the President at an event where we had just a few
moments to talk about it, and he turned the pursuit of this over to
Karl Rove who went to NIH and asked them about my suggestion that you
might be able to take cells from an early embryo, and he came back and
called me and said they tell me they cannot do that.
I said either they did not understand the question or there is some
confusion, because these are the same people that can take a single
cell and take the nucleus out of that cell and put another one in it.
That is what you do in cloning. If you can do that in a single cell,
obviously you have the capability of taking a single cell out of a
fairly large mass of cells.
So he went back a second time and asked them and they told him the
same thing, and so the President came down a few days later with his
executive order that all the stem cell lines we have produced by
destroying embryos; and since he was opposed to taking one life with
the hope that you might help another life, he could not support the
destruction of any additional embryos, but that Federal money could be
used in pursuing research and medical applications using what he was
told was roughly 60 lines of stem cells that were in existence at that
time.
{time} 2245
Several years later in my office, just this year, as a matter of
fact, talking
[[Page H4182]]
with the people from NIH, they explained how this misunderstanding
occurred. It is awfully easy to have misunderstandings when your
backgrounds are very different, which is one of the problems we have in
dialogues, of course. You can think that you are carrying on a dialogue
when you are really carrying on simultaneous monologues, which was
apparently sort of what happened in this discussion between Karl Rove
and NIH. Because what they had really told him was that they did not
know if they could make a stem cell line from such an early embryo, and
that is true, and that is why I wanted animal experimentation to
determine whether you could do that or not.
Our next chart shows some of this progression, and it shows what we
are talking about and what we were talking about there. This is half of
the reproductive life of a mother. It shows an ovary, and there is one
on each side, of course. Then it shows a funnel-like thing that sweeps
over the ovum, it is called the infundibulum, and then the fallopian
tube and down to the uterus. This shows just half of the tract. There
is a mirror image of this over on the other side.
By the way, there is an interesting thing that sometimes happens.
These sperm are very energetic. They are released, of course, in the
vagina of the mother, and they then make their way up into the uterus,
through the cervix into the uterus, and then they swim all the way up
the fallopian tube, and they can swim out through the end of the
fallopian tube out into the body cavity. Sometimes the egg is not
picked up by the cilia in the fallopian tube, and it also floats out
into the body cavity, and the egg can be fertilized there. We call this
an ectopic pregnancy and, of course, the baby cannot grow there, so
that has to be removed.
The ovum starts down the fallopian tube and very high up in the
fallopian tube, it is fertilized. Then it divides into two cells and
four cells and eight cells. It is at the eight-cell stage in the
laboratory. This same process of fertilization and growth occurs in the
petri dish in the laboratory, and it is at the eight-cell stage in the
laboratory that they ordinarily implant the embryos. This goes on, of
course, to produce the inner cell mass that we saw in the earlier chart
there which then differentiates into the germ layers. It is at these
later stages that it actually implants in the mother's uterus.
The convention is ordinarily that implantation is done at the eight-
cell stage. So my suggestion was that you could take a cell from the
eight-cell stage, and it would not harm the embryo. As a matter of
fact, if the embryo splits at this stage or at the two-cell stage or
down here at the inner cell mass stage of the two inner cell masses,
both groups of cells go on to produce a perfectly normal baby. So,
obviously, there was the potential that you could take a cell from an
early embryo without harming the embryo.
I have been carrying on this dialogue with the pro-life community and
with the scientists at NIH now for these 4 years. During one of these
discussions, the representative of the Catholic bishops, Mr.
Dorflinger, made a suggestion. There are some things that you see in
life that are just so obvious that you say, gee, why didn't I think of
that. His contribution was just that kind of thing. He said, in
addition to taking a cell out of that inner cell mass, and, by the way,
this is now done more than a thousand times around the world. We do not
know how many more than a thousand times. But in the laboratory they
want to know that this embryo they are going to implant in the mother
does not have any genetic defects so that they are going to have a
healthy baby. So they take a cell out of the eight-cell stage and they
do a preimplantation genetic diagnosis on it and then they implant
those remaining cells in the mother and more than a thousand times they
have had a normal baby born.
Mr. Dorflinger's suggestion was, and in addition to doing that
preimplantation genetic diagnosis that you also establish a repair kit.
That is kind of what you hope you are doing when you freeze umbilical
cord blood. You hope that there are some stem-cell-like cells in there,
that if there are future medical problems and stem cell research
development has gone on to the point that you can make some meaningful
applications that you could then be using tissues that would not be
rejected like the tissues from an embryonic stem cell from another
person.
But clearly if the repair kit was established from a cell taken from
an early embryo, it would be exactly the genetic composition of the
child, of the person, of the adult as they grew, and so any defect
could then be very effectively treated with tissues that would not be
rejected.
The President has a group of people, the President's Council on
Bioethics, and because of the enormous expected potential from stem
cell research, they have been looking at alternatives for embryonic
stem cell research that might be ethically acceptable and they have
just fairly recently issued a report, Alternative Sources of Human
Pluripotent Stem Cells. It is called a white paper. In the body of that
white paper they describe four different techniques.
The next chart shows a little paragraph from that, and I have
highlighted a part of it.
It says it may be some time before stem cells can be reliably derived
from single cells extracted from early embryos and in ways that do no
harm to the embryo, thus biopsied. But the initial success of the
Verlinsky's Group's efforts at least raises the future possibility that
pluripotent stem cells could be derived from single blastomeres. A
blastomere is simply a cell from the blastula. It merely means a cell
removed from the early human embryos without apparently harming them.
Then there is a little asterisk. If you go to the bottom of the page
you see, ``A similar idea was proposed by Representative Roscoe
Bartlett of Maryland as far back as 2001.'' This is the proposal that I
made to the President that was pursued by Karl Rove with the
misunderstandings that we talked about a few minutes ago.
In the body of their paper, they talk about four different
approaches. One of the approaches is to use embryos that obviously are
not going to live because they are really bad and they are going to
die. You could take cells from them like taking an organ from a person
who is brain dead. I would have a little concern, Mr. Speaker, about
how good a stem cell I was getting from an embryo that was dead.
Another suggestion is to manipulate the genes of the cells so that if
they develop they will never produce a baby. It would be kind of a
freak, I guess, and since it is not going to be a baby, then you could
take cells from that. Again, I would have a little concern, was I
really getting a normal cell when I was taking it from something that
was genetically engineered so that it was not going to grow to be a
baby?
In the text of their white paper, they do a very good job of talking
about developing the repair kit and the fact that the cells could
probably be taken without hurting the embryo. They look at all of the
pluses and minuses of this.
But then it looks like almost, Mr. Speaker, that somebody else wrote
the recommendations, because let me read from the recommendations here.
The recommendations say, the second proposal, blastomere extraction
from living embryos, we find this proposal to be ethically unacceptable
in humans owing to the reasons given in the ethical analysis: We should
not impose risk on living embryos destined to become children for the
sake of getting stem cells for research.
I agree. That is not what they talked about in the text of their
white paper. There they talked about preimplantation genetic diagnosis.
This clearly has to be for the benefit of the baby. The mother does not
want to have a baby that is going to have a less than optimum
opportunity for a good life with a genetic defect, and she has the
opportunity to determine that and so she does it. And then they also
talk about developing the repair kit.
So what we were proposing is that there would be cells made
available, surplus cells from the repair kit, only after the parents
had made three decisions which were in the interest of their baby. The
first decision was to do in vitro fertilization. I know that there are
those who do not believe that we ought to be doing in vitro
fertilization. They kind of think that is like playing God. But there
is an old axiom that I really subscribe to, Mr. Speaker, and that is
that man's extremity is God's
[[Page H4183]]
opportunity and God is not going to do for us what we can do for
ourselves. And these parents have made the decision they want a baby
and in vitro fertilization is the only way they are going to get one,
so they have made the decision.
Then they have made the decision they really want a healthy baby, so
they are going to do preimplantation genetic diagnosis. And, by the
way, they refreeze the embryo that was defective. It could be adopted.
There are some families and, God bless them, that are really fulfilled
by taking into their home handicapped babies, babies with defects, that
they are going to be with them for a lifetime and these people feel
fulfilled in taking these children into their homes, children who have
HIV, crack cocaine babies and so forth and so these embryos could be
adopted.
By the way, this is not genetic engineering. There have been some
suggestions that this is an unacceptable technique. Just looking at
what kind of genes are there, Mr. Speaker, that is not genetic
engineering. That is not a very believable argument against this.
Then the parents have made a third choice, and that is to establish a
repair kit for their baby. And only after the parents have made those
three what I think are ethical choices, they want to have their own
baby, they do not want their baby to have a genetic defect and they
want their baby to have a repair kit and only after they have made
those three decisions, then we would ask for some surplus cells from
the repair kit to establish a new stem cell line.
There are two things that I want to refer to here. One is a letter
from Dr. Battey, who is the spokesperson at NIH for stem cell research.
He wrote me on May 23, fairly recently, a three-page letter in which he
says, live births resulting from embryos which undergo preimplantation
genetic diagnosis and are subsequently implanted seem to suggest that
this procedure does not harm the embryo. At least for a thousand times
we have had a normal baby. They are not adults yet, and so the clock
has to run for a while before we determine whether there is any defect.
I would be very surprised, Mr. Speaker, if there is a defect. Because
you can take half the cells away from an early embryo to produce
identical twins, and both halves produce what looks like perfectly
normal people. So I would be surprised if there is any long-term
effects from this.
Also, it is not known if the single cell removed from the eight-cell
stage human embryo has the capacity to become an embryo if cultured in
the appropriate environment.
Then I would like to turn, Mr. Speaker, to the Science section,
Monday, June 6, just yesterday, Stem Cell Advances May Make Moral Issue
Moot. A Dr. Lanza, and our office has spoken to Dr. Lanza, he is
publishing a paper imminently. Some of the details could not be in this
article because he was holding those for his paper.
In one approach pioneered by Robert Lanza and colleagues at Advanced
Cell Technology in Worcester, Massachusetts, researchers plucked single
cells from eight-cell embryos, embryos so young they do not have stem
cells yet. Stem cells are ordinarily derived from inner cell mass. I do
not understand saying that these are not the conventional stem cells
but they certainly, I think, have the capacity to produce stem cells.
Fertility doctors have known for years that early embryos seem
unfazed by the removal of any one of their eight virtually identical
cells called blastomeres. In fact, it is common today to remove a
single representative blastomere from a laboratory conceived embryo and
test that cell for diseased genes before deciding whether to transfer
that embryo into a woman's womb.
If this technique were applied to humans, and I skipped a couple of
paragraphs where he talks about work with animals, if this technique
were applied to humans, then a single cell taken from an eight-cell
fertility clinic embryo could give rise to a self-replicating line of
embryonic stem cells without compromising the donor embryo's odds of
someday growing into a baby.
So the thing that Dr. Battey said had not yet been, and he was
correct because this paper is yet to be published, I think it may be
published today or tomorrow, but he has now in mice, and if it is
doable in mice it is probably doable in higher animals, including
humans, that they have developed stem cell lines from a single cell
taken from an early blastomere.
I would just like to spend a few moments now talking about the bill
which we have filed. It has a number of cosponsors, and I am very
pleased that several doctors in the House have signed on to our bill.
{time} 2300
Our bill really has nothing to do with working on humans because we
think that we ought to do some animal experimentation before we start
working with humans. So what our bill does is simply to make some
moneys available for a several-year study, and we ought to go up to
nonhuman primates. These are animals like chimpanzees and the great
apes. To make sure that what has been done in mice and what has been
done more than 1,000 times in these clinics, and what has been done, of
course, is taking cells from an early embryo without apparently hurting
the embryo, that we could develop these cells into a stem cell line.
That has now been done, as was noted in the paper yesterday. This is
the science section of The Washington Post. So the potential is there
to do this. And all that our research does is to ask for animal
experimentation so that we can check and double-check and make really
sure that this is a safe procedure for humans.
I would like to put up the last chart that we are going to refer to
now. This is a little bit like one that we looked at previously. This
shows again half of the reproductive tract of the female; and, of
course, what we are talking about are procedures that are done in the
laboratory. But they are mimicking what happens in the body. By the
way, when the little baby girl is born, she has in her ovary all of the
ova that will ever be there, and they mature generally during her
reproductive life, which may span 30, 40 years. They generally mature
from one side or the other one a month. But they are all in there. And
this shows the development of these ovum. And finally they grow and
there is like a little blister on the side of the ovary, and then it
breaks and the ovum is free.
In the laboratory, of course, these have been washed out of the
reproductive tract of the female, and they are now put in petri dishes
and exposed to sperm. In the body, the sperm is deposited in the
vagina, makes its way through the cervix, up through the uterus, and
swims clear up through the Fallopian tube. In a laboratory, of course,
they simply with a pipette put the sperm in the petri dish with the
ovum. And there will be many sperm. There are millions of sperm. And
really quite a miraculous and very rapid transformation takes place. As
soon as one sperm enters the egg, the egg then sets up a defense so
that no more sperm can enter because if another sperm were able to make
its way in and they had three sets of chromosomes instead of two, that
would be fatal.
By the way, in flowers that is not fatal. That is called polyploidi,
and that is how we get bigger flowers and better smell and so forth.
But plants react very differently to extra hormones than humans do.
Tisomy-21 produces mongoloid babies. That is just having one extra of
one chromosome. So we do not react well to extra chromosomes; and so
the ovum, after one sperm has entered, it sets up this defense so that
no more sperm can enter.
The same thing happens in the laboratory. And then it divides, and
the doctor watches that division. And down at eight-cell stage, they
take a cell out and do preimplantation genetic diagnosis; and as recent
research has demonstrated, the paper that is going to be published very
shortly by Dr. Lanza, they have done this in mice, but if it is
possible there, it ought to be possible in higher animals, and our
research would determine that. They have produced stem cell lines from
a single cell taken. What this means is, Mr. Speaker, that we now have
been able to produce, we will be able to produce, embryonic stem cell
lines without harming an embryo.
I have heard people say that they are just unalterably opposed to
embryonic stem cell research. I hope that is not what they mean. I hope
what they are
[[Page H4184]]
mean is that they are unalterably opposed to embryonic stem cell
research if it means killing an embryo. I am unalterably opposed to
embryonic stem cell research if it means taking one life with the hope
that we will be able to help another life. But with these recent
advances in medicine and research in the laboratory, there is the real
hope that we can take cells from an early embryo to benefit the embryo.
And I would like to say again the reasons that the parents are taking
cells from this early embryo, the fundamental reason they are taking
the cell is to do a preimplantation genetic diagnosis. And the
President's Council on Bioethics mentions the possibility of creating a
repair kit, which certainly would benefit the baby. So the parent has
now done three things which they think is ethical. I think that they
are ethical, and there ought to be surplus cells from the repair kit,
and it is those surplus cells that would be made available for
additional stem cell lines.
But I want to reiterate again that the bill which we have just looks
at animal experimentation. Although human research, human developments,
human applications have gone beyond some of the exploration that we
have done with animals, we still think that it is prudent to work with
animals where we can determine with more cases and more intense
experimental observation to make sure that there are no untoward
effects of doing this.
I hope that this research can bring the two sides together. We had a
couple of weeks ago a very heated debate. The emotions on both sides
were rather obvious: those who wanted to take some of these more than
400,000 frozen embryos that they said were going to be discarded anyhow
to get some good from them, and they were so convinced of this in
California that they voted for $3 billion to proceed with this. The
argument on the other side, which position I take, is that morally I
have big problems with taking one life, and this little embryo could
become under the right circumstances a baby. More than 100 times it
has. From these frozen 400,000, there are about 100 or so, we call
Snowflake babies, because this is a program to offer these embryos for
adoption, and more than 100 times they have been adopted, and the
President had some of those babies at the White House a couple of weeks
ago when we were having that debate, and they came to the Hill also
when we were having that debate here on the floor.
With the ability to take cells from an early embryo not to establish
a stem cell line, that is not why the parents took it. They took the
cell to do a preimplantation genetic diagnosis. They then would like to
establish a repair kit. We know they would like to do that because they
are more and more freezing umbilical cord blood, which, as the one
doctor I read from said, is a poor second choice to an embryonic stem
cell line, but it is better than nothing. So we know that parents would
like to do that. And it is only after that if the animal
experimentation supported by our bill shows that this is efficacious
and will not harm the baby, only after that would stem cell lines be
derived from surplus cells from repair kits that the parents had
decided to establish for the benefit of their baby.
I think, Mr. Speaker, that this ought to remove all of the ethical
objections. But there is just one more, and I just want to spend a
moment talking about that, and this is a good chart to talk about it
from. Since these cells at the eight-cell stage are quite
undifferentiated, which means they have not really decided what they
are going to be, it is possible that they might take that one cell and
establish another embryo. The President's Council on Bioethics thinks
that is very unlikely. But what I would like to see them pursue is the
development of stem cell lines and the preimplantation genetic
diagnosis from the inner cell mass stage.
Now, that is the stage at which embryonic stem cells are ordinarily
taken from when the embryo is destroyed. That is before the embryo is
implanted in the normal process. Here is the inner cell mass, and here
is where it is implanted a couple of days later, 2 or 3 days later, in
the uterus.
{time} 2310
Ordinarily, and I am not sure why they use the eight cell stage in
the clinical laboratories, but I would like to see cells taken from the
inner cell mass. There is no ethical question involved there because
these cells in the inner cell mass cannot produce a baby because they
have already lost their ability to produce decidua. The decidua is the
amnion and chorion which is commonly known as the placenta, and they
have lost the ability to do that, so they cannot produce a baby, but
they can produce all of the tissues of a person, because these are what
produce, back to our first chart that shows the inner cell mass
differentiating into these three germ layers.
So the last possible ethical objection to deriving stem cells from
pre-implantation genetic diagnosis and the development of a repair kit
would be gone if we could take the cell from the inner cell mass,
because the inner cell mass, those cells could not possibly produce a
baby, because they are sufficiently differentiated that they cannot
produce the decidium.
I have used this term ``differentiation'' a number of times, and what
we try to do with adult stem cells, because they are already
differentiated, we try to de-differentiate them. We try to confuse them
with ques, with chemicals, with exposing them to other cells and the
products from other cells so that they can kind of forget their
development and they now go back to a prior less-differentiated state
where they could produce more variety of cells. But you avoid those
problems with the embryonic stem cell, because it has the capability to
produce any and every cell in the body.
Mr. Speaker, I believe that with these recent medical advances, with
the knowledge that we have, that it is perfectly feasible to ethically
develop embryonic stem cell lines from embryos which should have, in
the view of many of the experts, and clearly in the view of most
Americans if you poll them, should have more potential than adult stem
cells. Only research will tell that, and only time will tell whether or
not that is true.
But with the hope that these large numbers of diseases so devastating
to our people could be affected or maybe cured with embryonic stem
cells, we really must pursue this, and now we have the opportunity to
do that without offending those who have a problem with taking one life
so that we might help another life.
I think, Mr. Speaker, that we now are on the cusp of advances that
will bring these two sides together. We have enough things to be
concerned about and to discuss in our country, we do not need to be
discussing this, and I think the two sides with these present advances
can come together. I hope that we will have an early vote on our bill
and it will reach the President's desk so that he has a bill that he
can sign that will promote embryonic stem cell research.
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