Two respected scientific journals today reported that Chinese researchers have created baby mice out of induced pluripotent stem cells ("iPSCs"), an advance that raises difficult ethical questions and could reignite the culture-war battles over stem cell research that have subsided over the last two years.
Many conservatives oppose human embryonic stem cell (hESC) research, and President George W. Bush severely limited its funding, because the five-day old embryos (called blastocysts) that are used are living organisms and, if implanted into a uterus, could mature into people. Although President Obama lifted the Bush funding restrictions, the NIH released new guidelines that are still solicitous of the discomfort many Americans feel about using blastocysts for medical research: the Obama administration will fund such research only if the blastocysts used are "extras" created in in vitro fertilization clinics and would otherwise be destroyed anyway. Want to create a blastocyst in a test tube in order to produce stem cells? Don't look for federal funding, even from a Democratic administration.
The new federal regulations have provoked relatively little media attention, in part because most scientists have believed for the last year or two that hESCs are a transitional technology about to be overtaken by a newer one. In late 2007, scientists succeeded in reprogrammed ordinary adult skin cells (and other types of adult cells) into cells that seem to behave, for all practical purposes, like hESC cells. Scientists still aren't sure that these new iPSCs will behave exactly the same as hESCs for purposes of medical research, but the available evidence looks good, and iPSCs have a number of advantages over hESCs. They are much easier to produce than hESCs, and unlike hESCs, iPSCs offer the potential of allowing scientists to one day use a patient's own cells as the basis for creating a stem cell treatment that would not create problems of immune system rejection. And, of course, iPSCs do not come from embryos that could develop into a person, so iPSC research has met with widespread approval by conservatives who oppose hESC research.
But what now? If an iPSC can develop into a baby, just as a blastocyst can, why is it any less troubling to use iPSCs for medical research than it is to use hESCs? One possible response is that iPSCs can't become people without human intervention, but the same can be said of the blastocysts created in test tubes that are used for hESC research, which need to be placed in a womb. A difference between iPSCs and blastocysts is that the latter have a new, unique genome, whereas the former have the same genome as their donor. But we don't think identical twins are any less morally valuable because they lack a unique genome, and we wouldn't think that a cloned person was not a person, just because she had the same genome as her genetic donor.
My view is that today's development underscores the logical problem with treating blastocysts as if they have the same moral worth as a person. If it seems implausible that we should treat every skin cell as if it were a person, this is because the foundation of personhood is not a human genome plus potential. There must be something more, whether it be a neuronal structure, sentience, consciousness, the ability to imagine a future, etc. But for the unconvinced — and especially those whose religious or ideological commitments make them opposed to any research using blastocysts — opposition to iPSC research might be the only internally consistent position to take.
If a scientist wants to grow you a new liver in a petrie dish, that is fine. If he wants to do that by cloning you, growing the blastocyst into a fetus and then killing the fetus to harvest the liver, that is another matter altogether.
You seem to be confusing two separate issues, there is nothing per se wrong with using hESCs for research - the problem comes about because there is no non-destructive way to acquire hESCs. Find a way to get hESCs without harming an embryo and you should have no problem acquiring federal funding for your research. Likewise, if to acquire PSCs you have to kill someone in order to harvest them there would be a significant problem.
Now, we can use the genetic material from a skin cell to create a new human organism. But this doesn't make the skin cell a potential human organism in any interesting sense. And again, it isn't potentiality that matters. The blastocyst IS a human organism, a skin cell is not.
QUERY: I've always been uneasy with the claim that iPSCs let us have our cake and eat it too. In particular, I've never seen anyone explicitly state that iPSCs aren't created by using the genetic material from some cell to create a new human being, and then to use that new human being's hESC cells. I'd be very happy if someone could convince me that that isn't so. Anyone?
I can never get anybody on the conservative side (where I am on most issues) to focus on real concrete specifics with therapeutic cloning (and the same technical aspects apply here, too):
In therapeutic cloning, you begin with two cells. One is a skin cell or cell from the stomach lining or somewhere similar. The other is an egg cell. Neither of those cells is "life" (in the sense that term is used in these debates). The haploid DNA from the egg cell is removed and discarded. This poses no significant moral issues. The DNA from the skin cell is also removed, and injected into the denucleated egg cell. The resulting hybrid cell is placed in a calcium bath and given a jolt of electricity (I'm simplifying the process, but this is the basics). It then becomes a pluripotent stem cell which, if placed in a receptive uterus, has the potential to develop into an infant.
The fundamental question which must be asked is at what point does that hybrid cell become "life"? Is it with the calcium bath? The jolt of electricity?
The same question applies with this new discovery. At what point does one of my skin cells become independent "life"? I suspect that few would want to say that the scientists who do this are actually creating "life" where it did not previously exist.
For myself, I adopt a dual-level definition of when "life" begins (those aren't scare quotes, I just want to emphasize the distinction between things that are "living" or "alive" and things that constitute separate "life"). When we're talking about the combination of egg and sperm cells to form a new genetic entity which never previously existed (in the entire history of mankind), then "life" begins at the moment of that conception. However, when we're talking about manipulating the individual cells of an existing independent being (with no new genetic combination involved -- and please no quibbling over mitochondrial DNA from the egg), then it's not "life" unless and until it's implanted in a uterus.
I would say by some objective standards... Not all by any stretch.
I disagree, potentiality is the point, not beside the point at all. A blastocyst is the embodiment of human potentiality in a way that a skin cell isn't, or at least wasn't before the work that triggered this post.
There are few biological differences other than the inherent potentiality between a blastocyst and a similar-sized ball of skin cells. Neither is sentient, both need similar environmental conditions, etc. THE major difference is that a blastocyst generally develops into a mature individual while a skin cell just makes more skin cells (or occasionally a tumor).
I would actually put point Y well beyond birth, and many don't even reach it, despite being a fairly low standard even then. Certainly not as rigorous as Frank Herbert's definition.
What are eggs and sperm if not alive? Obviously they belong to the animate world not the inanimate one, so the question becomes what species are they? Obviously h.sapiens. They are the haploid phase in the lifecycle of the species h.sapiens. As far as biologists have been able to determine life started once, billions of years ago. All living things on Earth are linked by a web that stretches back to a universal common ancestor.
Now do you start to see the problem? If you'll notice what I did there, I took one stage of the development of a human being and replaced it with another.
The difference is between destroying a human being in the embryonic stage of development and destroying cells from a human being in a later stage of development that have been manipulated in order to become pluripotent.
Even now that these cells are pluripotent they will not simply grow into an adult human being given proper nutrients and oxygen and those things that human beings need to survive (this would be done by placing a tiny human being in a receptive womb, which would then provide those nutrients via blood from the mother until the human being had advanced enough to be able to receive those nutrients via the mother's milk). That is what a human being in the embryonic stage of development would do.
No, a batch of pluripotent cells that came from an adult human beings skin will not do that. However, potentially, we may possibly be able to someday manipulate them yet again and get them to become a human being in the embryonic stage of development. At which point of course it would become wrong to experiment upon them and destroy them without just cause.
Cheers,
Cheers,
Furthermore, that this is possible in humans is questionable due to the biological differences in mice and human embryos and stem cells.
But by comparing embryos to skin cells, you miss the crux of the opposing argument. Rights are conferred based upon what we are as human beings, not by some ability we will eventually take possession of or acquire.
Har, har. Besides the lame attempt at a joke you also don't seem to have a proper grasp of biology. A human being in the embryonic stage of development does have a heart...and a brain...and everything else...and they all look exactly as you'd expect the brain and heart and everything else to appear at that stage of development in a human being. It would be imbecilic to expect a human being in that stage of development to have a heart that looks like your heart. We do know that it is there, we do know that it is functioning exactly as expected for that stage of development. We know this because at no point does someone have to implant a heart or a brain in order for that human being to have a brain or heart some days later. It was already there!
I think I see your problem a bit. It's very common. You mistake living organisms (individual living cells) with living organisms that are made up of many different living organisms (a complete human being). Maybe it would be best to refer to a human being as a system of living organisms and each individual cell as a living organism. Without that distinction we could arbitrarily kill all human beings because when you take each individual set of living organisms (skin cells, blood cells, nerve cells, etc.) you do not see anything that must be protected. You could then legally destroy all of those. Yet if you did that you would kill that system of living organisms and thus kill that person.
A new system is started every time a spermatozoa from a male joins with an ovum from a female. Before that joining they were simply parts of separate systems of living organisms. After that joining they now become a new unique individual system of living organisms (well at first that entire system is one living organism which then divides to two and then four and so on and so on).
But this would mean we could kill with impunity newborn infants, people in deep sleep, those in comas, etc. That is why we should protect any creature, no matter how small, strange looking, mindless or deformed, who, in normal development, will become a human being with sentience in time. This is the only definition that protects all human beings and avoids the problems listed above. And that's why an embryo that is created and has the innate ability to become a human being is a developing human being and must not be killed, and indeed must be provided (by the creator) with the proper nourishment and environment to be kept alive until adulthood.
Rights are not "conferred" but "recognized", and necessarily on the basis of discernable attributes. The problem is that we are moving from an age when those were the simple attributes of having been born to a human female, and the more complex and subtle attributes that must soon define the boundaries between "personhood" and "nonpersonhood".
Suppose some of those science fiction scenarios actually occur, and court appearances are made by genetically enhanced speaking animals, or androids, or space aliens, or disembodied computer programs that manifest the downloaded personality of a formerly embodied human, and that entity demands the rights of due process of a person. What do we do then? We need to get ready for that, because it is coming.
Once we establish tests for personhood that include the above, we are going to have biologically human progeny failing the tests, and we have to get ready for that, too.
So prior to cell differentiation it's not a person? In that case, you shouldn't have a problem with stem cell research, as the entire point of fetal stem cells is that they're undifferentiated tissue.
MatthewM: But this would mean we could kill with impunity newborn infants, people in deep sleep, those in comas, etc.
Someone whose brain functions have ceased is dead, and there's no moral issue with turning off life support. For that matter, I don't have an issue with turning off life support for someone in a persistent vegetative state, such as Terri Schiavo. The fetal brain won't reach those levels until the 3rd trimester.
Incidentally, it's worth pointing out that hESCs are generally derived from medical waste from fertility clinics. These are not cells that would otherwise turn into a human, they're cells that would otherwise be incinerated as medical waste.
There's your difference.
Something doesn't have to be a "person" to be protected under the law. We also protect animals, historic relics, and other things that are not "persons". See this blog post for a more expansive discussion.
Cheers,
You do know that the "homunculus" theory died a just death a century ago, right?
Cheers,
And some would argue that "outside intervention" (in the form of a uterus) is necessary even in the case of an in vivo blastocyst.
Cheers,
For example, at various times, people have travelled to Paris in both Shermans and 747s. While the destination was the same, the meanings of the journeys were completely different.
Some hold that how a cell came to be matters as well, not just where it might go in the future.
I see the arguments about blastocysts not having the same moral equivalent as humans, but I see arguments that they do have it, and I think society is better off if we err on the side of life. A more-or-less arbitrary line has to be drawn, and will be drawn, and the only question is where. I remember something that happened over 20 years ago: a man in California had Parkinson's disease, and his daughter wanted a court order to allow her to become pregnant by him so that the fetus's brain tissue could be harvested and implanted. The court refused, but it's kind of hard to see why on a strictly objective basis, since abortion was legal at that time (as it is now.) Certain things are icky, and they need to stay icky, or we'll slide down that slippery slope to hell. Because one thing you cannot count on is "nobody would ever..." anything, anything at all.
I don't understand. The brain is doing exactly what a brain does at that stage of development.
This is so utterly different than someone who once had a fully functional brain that is now brain-dead. Please don't tell me that you are going to say that a human being whose brain is functioning perfectly in the pre-born stages of development (i.e. exactly as you'd normally medically expect the brains to function at those stages), is anything remotely like a post-born human being whose brain has been irreparably damaged?
Yes, and not provided with the nutrients necessary to continue the cellular division and development necessary to develop into an adult human being. You nailed it!
Are you trying to say that if I examine something brought into my biological disposal facility with my microscope and only notice a clump of cells that it is perfectly alright to incinerate it?
Well then please come on into my biological disposal facility Anthony! You and I are merely clumps of cells!!
I was not referring to differentiated structures. Even before differentiation the heart and the brain are there. If you were to record the division of the cells from conception forward and then after you are happy with there definitely being a brain and a heart in the developing human being, you rewind the video footage, watch the cells that make up that heart and that brain, observe backwards these cells and all of the other cells that make up this unique collection of cells, this system of living organisms. What you see is that you can follow a complete system all the way until the zygote.
One cell. One whole and complete system of living organisms. Before that two separate living organisms that were parts of separate systems of living organisms.
That one zygote differentiates and divides, repeatedly over and over. The old cells die off. In 10 years we will not exist as all of the cells in our bodies currently will have been replaced (well with a small percentage of cells being exceptions of course). I began dividing over 34 years ago and continue to do so today.
If you mean feeding then, yes, "outside intervention" is required. Just like with my newborn boy and girl they also needed "outside intervention" in order to advance towards the adult stage of development.
Providing the nutrients necessary to continue, however, is the bare minimum that humans ought to be required to provide for fellow humans.
I smell a movie in the making.
The issue of when life begins, and even if it could begin from other sources besides a woman's egg fertilized by a man's sperm, are kind of secondary to the issue of if we are going to allow other methods of creating people besides by joining a man and a woman's unmodified genes.
As to when life begins, the bible says the life is in the blood. The heart pumping blood is distinct from chemical reactions of cellular life, in that it is sheer will power of a whole-organism to pump the life around. Life ends very soon after the heart stops pumping fresh blood through the body, the life that is in the blood is still in the blood, but it stops being pumped into the body.
Right. Essentially nothing.
Please don't tell me that you are going to say that a human being whose brain is functioning perfectly in the pre-born stages of development (i.e. exactly as you'd normally medically expect the brains to function at those stages), is anything remotely like a post-born human being whose brain has been irreparably damaged?
One is pre-person. The other is post-person. Neither is a person.
Yes, and not provided with the nutrients necessary to continue the cellular division and development necessary to develop into an adult human being. You nailed it!
You're missing the point. If those cells are a person, it's obviously wrong to destroy them. In addition, there is no way an IVF clinic can function without producing such waste cells. So, should IVF clinics be banned?
Right, the whole body is in every cell in the body. The DNA is (supposedly) identical and complete in every cell. It just takes getting a cell containing a complete diploid genome to start dividing like zygotes do and putting it in an environment where it can come to life and exert will to live as an organism and become human.
Yes, there would be lots of biotech people out of work, but we can pay them half their salaries for a little while, while we retrain them as farmers and craftsmen.
Oh and for the record, to some commenter above, it's "eat your cake and have it to". Once I found the true quote that phrase made a lot more sense to me.
I read this and immediately thought:
Beware of trying to extend "personhood" to black people. Suppose you do. What do you do if an elderly widow depends on her slave for her livelihood?
I seem to recall that abortion was outlawed in this country at one time, with no such actions happening on a routine basis.
Ding! Ding! Ding! Ding! Give that man a medal! You nailed it! Yes, IVF clinics need to be banned. Next question?
Cheers,
JOOC, though, to plumb your 'logic' to even greater depths: If cell "growth" is the result of cell division, and you have 10^10 cells back then and 10^10 now (giver or take an order of magnitude), how are these all "new" cells?!? !? Where'd they come from? Alien spores?
Cheers,
Cheers,
Actually, there's plenty of evidence that the stem cell research debate is just a byproduct of opposition to abortion. Killing a blastocyst doesn't "stop a beating heart", a blastocyst doesn't let out a "silent scream", etc. It would be really easy to oppose abortion while permitting stem cell research, as the Mormon Church does.
But because "life begins at conception" imposes greater controls female sexuality, pro-life advocates have ended up taking a completely incoherent and intellectually indefensible position that we can't even destroy a clump of cells to cure cancer and save millions of people.
Since there's no logic or humanity in that position, it sure looks like the real motivation is controlling women's sexuality.
Because an iPSC is not a blastocyst and is not obtained by eviscerating blastocysts or human beings in any other developmental stage.
Moreover, I fail to see what's so remarkable or morally challenging about this new technique with regard to the pro-life position. A human ovum can develop into a baby by being fertilized by a human sperm. I've personally triggered this transformation multiple times, starting over 6 years ago - without even needing a nano-pipet! (ok, ok, I hear your snickering). Also, I frequently use spermicide, but sperm != human being, so I remain morally consistent here.
Note to Dilan: "life begins at conception" is a scientific fact. That, not any of your messed-up ad hominem (i.e. logically fallacious) attacks, is the basis of the pro-life movement.
Then again, given that you were dumb enough to take the bait set out for you, I'm not sure that I would credit you with intelligence beyond that of your average mouse.
No, the scientific fact is that life began billions of years ago and has been a continuous process ever since. Life comes only from life, all the way back to the first bubble of self-catalytic RNA.
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