Home Search First Look Rules Help TheDaddy.org BlogLogin/Register
By bye hackers
Cytoplastic hybrids (and all that jazz) - 1 to 8
Return To The Big Questions

Emo Squid
sanctus, sanctus, sanctus
Wed 5th Sep '07 5:47PM
624 Posts
Emo Squid's Avatar
Member Since
23rd Feb '07
Medical researchers believe that stem cell treatments have the potential to change the face of human disease and alleviate suffering.
Since stems cells have the potential to be differentiated into basically all cell types, they offer promise in the development of medical treatments for a wide range of conditions. These include damage to the brain, spinal cord, skeletal muscles, and the heart. Treatments that have been proposed follow either physical trauma (e.g. spinal cord injuries), degenerative conditions (e.g. Parkinson's disease), or even genetic diseases (in combination with gene therapy).

Much success and potential has been demonstrated from research using adult stem cells. Nevertheless, some are of the opinion that the differentiation potential of embryonic stem cells is broader than most adult stem cells. In addition, embryonic stem cells are considered more useful for nervous system therapies, as researchers have struggled to identify and isolate neural progenitors from adult tissues. Embryonic stem cells, however, might be rejected by the immune system - a problem which wouldn't occur if the patient received his or her own stem cells.

(Reuters) - Regulators decided today to permit in principle the creation of hybrid human-animal embryos for research into illnesses such as Parkinson's, Motor Neurone Disease and Alzheimer's. The resulting "cytoplastic hybrid" embryo would be 99.9 percent human and 0.1 percent animal. Two teams of British scientists have applied to the HFEA for permission to create such hybrids to overcome a shortage of donated human eggs.
The HFEA will now consider the two research applications in the coming months.
The HFEA regulators deferred a decision on other types of human-animal embryos, such as "true hybrids", created by the fusion of a human sperm and an animal egg, and "human chimeras", where human cells are injected into animal embryos.

(Wikipedia) - Arguments for embryonic stem cell research

(1) The utilitarianism argument

The benefits of stem cell research outweigh the cost in terms of embryonic "life"

* Embryonic stem cells have the capacity to grow indefinitely in a laboratory environment and can differentiate into almost all types of bodily tissue. This makes embryonic stem cells an attractive prospect for cellular therapies to treat a wide range of diseases.

* The social, economic and personal costs of the diseases that embryonic stem cells have the potential to treat are far greater than the costs associated with the destruction of embryos.

(2) The human potential vs humanity argument

The value of an embryo should not be placed on par with the value of a child or adult

This argument often goes hand-in-hand with the utilitarian argument, and can be presented in several forms:

* Embryos, while of value, are not equivalent to human life while they are still incapable of existing outside the womb (i.e. they only have the potential for life).

* Approximately 18% of zygotes do not implant after conception. Thus far more embryos are lost due to chance than are proposed to be used for embryonic stem cell research or treatments.

* Blastocysts are a cluster of human cells that have not differentiated into distinct organ tissue; making cells of the inner cell mass no more "human" than a skin cell .
* Some parties contend that embryos are not humans, believing that the life of Homo sapiens only begins when the heartbeat develops, which is during the 5th week of pregnancy, or when the brain begins developing activity, which has been detected at 54 days after conception.

(3) The consequentialism argument

The ends (i.e. new treatments and cures) justify the means (i.e. the destruction of embryos)

This can be seen as a more extreme view of the utilitarianism argument.

(4) The efficiency argument

If an embryo is going to be destroyed anyway, isn't it more efficient to make practical use of it?

* In vitro fertilization (IVF) generates large numbers of unused embryos (e.g. 70,000 in Australia alone). Many of these thousands of IVF embryos are slated for destruction. Using them for scientific research utilizes a resource that would otherwise be wasted.

* While the destruction of human embryos is required to establish a stem cell line, no new embryos have to be destroyed to work with existing stem cell lines. It would be wasteful not to continue to make use of these cell lines as a resource.
* Abortions are legal in many countries and jurisdictions. A logical argument follows that if these embryos are being destroyed anyway, why not use them for stem cell research or treatments?

(5) Arguments for the superiority of embryonic stem cells

Embryonic stem cells can be considered far more useful therapeutically than adult stem cells

This is usually presented as a counter-argument to using adult stem cells as an alternative that doesn't involve embryonic destruction.

* Embryonic stem cells make up a significant proportion of a developing embryo, while adult stem cells exist as minor populations within a mature individual (e.g. in every 10,000 cells of the bone marrow, only 10 will be usable stem cells). Thus, embryonic stem cells are likely to be easier to isolate and grow ex vivo than adult stem cells.

* Embryonic stem cells divide more rapidly than adult stem cells, potentially making it easier to generate large numbers of cells for therapeutic means. In contrast, adult stem cell might not divide fast enough to offer immediate treatment.

* Embryonic stem cells have greater plasticity, allowing them to treat a wider range of diseases.

* Adult stem cells from the patient's own body might not be effective in treatment of genetic disorders. Allogeneic embryonic stem cell transplantation (i.e. from a healthy donor) may be more practical in these cases than gene therapy of a patient's own cell.

* DNA abnormalities found in adult stem cells that are caused by toxins and sunlight may make them poorly suited for treatment.

* Embryonic stem cells have been shown to be effective in treating heart damage in mice.

(6) Fertilization is not the beginning of life

* Clones can be produced without fertilization taking place, and the clones are alive.

* Before the "primitive streak" is formed when the embryo attaches to the uterus at approximately 14 days after fertilization, the fertilized egg can split in two to form identical twins. Also, rarely, two separately fertilized eggs can fuse together to form a tetragammetic chimera - a single human individual with half of his cells being male from the original male embryo, and half being female from the original female embryo.

* Therefore before the primitive streak is formed, an individual human life does not exist at fertilization, as it can go on to split into two separate individuals. Therefore, an individual human life begins when the primitive streak is formed - beyond which the cell group cannot split to make twins - and not before. Therefore the blastocysts destroyed for embryonic stem cells do not have human life, and it is ethical to use them.

Arguments against embryonic stem cell research

(1) Embryos are lives

An embryo is actually a human, therefore it should be valued as highly as a human life.

The reasoning can be summed up by the fact that, once an egg is fertilized, unless inhibited, it will develop into a fully-developed adult. This opinion is often related to religious doctrines which assert that conception marks the beginning of human life or the presence of a soul. Based upon this reasoning, the subsequent argument against embryonic stem cell research is that human life is inherently valuable and cannot be involuntarily destroyed to save another life.

As an extension of this, it is argued that the tendency by some supporters of embryonic stem cell researchers to dismiss the ethical significance of embryo destruction may act to devalue human life.[citation needed] Moreover, it has been argued that "the line at which an embryo becomes a human life remains as arbitrary as ever".

Viability is another standard under which embryos and fetuses have been regarded as human lives. In the United States, the 1973 Supreme Court case of Roe v. Wade concluded that viability determined the permissibility of abortions performed for reasons other than the protection of the woman's health, defining viability as the point at which a fetus is "potentially able to live outside the mother's womb, albeit with artificial aid." The point of viability was 24 to 28 weeks when the case was decided and has since moved to about 22 weeks due to advancement in medical technology. If further technological advances allow a sperm and egg to be combined and fully developed completely outside of the womb, an embryo will be viable as soon as it is conceived, and under the viability standard, life will begin at conception.

(2) Alternative therapeutic options should be better explored

Embryonic stem cells should be abandoned in favor of alternatives, such as those involving adult stem cells.

This argument is used by opponents of embryonic destruction as well as researchers specialising in adult stem cell research.

It is often claimed by pro-life supporters that the use of adult stem cells from sources such as umbilical cord blood has consistently produced more promising results than the use of embryonic stem cells. Furthermore, adult stem cell and cord blood stem cell research may be able to make greater advances if less money and resources were channeled into embryonic stem cell research.

Adult stem cells have already produced therapies, while embryonic stem cells have not. Moreover, there have been many advances in adult stem cell research, including a recent study where pluripotent adult stem cells were manufactured from differentiated fibroblast by the addition of specific transcription factors. Newly created stem cells were developed into an embryo and were integrated into newborn mouse tissues, analogous to the properties of embryonic stem cells.

This argument remains hotly debated on both sides. Those critical of embryonic stem cell research point to a current lack of practical treatments, while supporters argue that advances will come with more time and that breakthroughs cannot be predicted.

(3) Scientific flaws in embryonic stem cell research

The use of embryonic stem cell in therapies may be fundamentally flawed.

For instance, one study suggests that autologous embryonic stem cells generated for therapeutic cloning may still suffer from immune rejection. The researchers note that: "Our results raise the provocative possibility that even genetically matched cells derived by therapeutic cloning may still face barriers to effective transplantation for some disorders." In other words, therapeutic cloning may not always produce matched tissues. In contrast, there are reports of adult stem cells being successfully reintegrated into an autogenic animal.

Another concern with embryonic stem cell treatments is a tendency of stem cells from embryos to create tumors. However, the tumorigenic potential of embryonic stem cells remains poorly described.

(4) Overstatement of research potential

Scientists have long promised spectacular results from embryonic stem cell research, and this has not yet occurred

Conspicuously, such criticism has even come from researchers themselves. For example, in November 2004, Princeton University president and geneticist Shirley Tilghman said, "Some of the public pronouncements in the field of stem-cell research come close to overpromising at best and delusional fantasizing at worst." Similarly, fertility expert and former president of the British Association for the Advancement of Science, Lord Winston has warned of a public backlash against stem cell research if it fails to deliver on some of the "hype" surrounding potential treatments.

I do quite a bit of work with the Manchester Medical School (videos, seminars, etc) and this seems to be a subject that academics are greatly divided on. I'm having a lot of trouble deciding which side of the fence to sit on. On the one hand, I think that research into all potential treatments for the diseases mentioned above is emmensely important, should be persued and that such research should not be so reliant on public funding (that's another debate all together). On the other hand - and this applies to most areas of medical advancements - I'm left wondering where the balance between human intervention and the process of natural selection lies. I'm no authority on this what so ever, but so long as we blinkeredly continue to prolong/'improve' the lives of those around today, I can't help think we're paving the way for a much more complicated future. Yet, conversely, I harbour hopes that this kind of research will lead to a quantum leap in disease therapy - largely because cancer and heart trouble runs in the family and my uncle (a wonderful human being) is being tested for Parkinson's at the moment. It's very difficult to have a personal attachment to something and maintain objective, I guess.

Thoughts?

Diziet
optical moose
Wed 5th Sep '07 5:59PM
2522 Posts
Diziet's Avatar
Member Since
20th Jul '05


Emo Squid was bold enough to comment:

Thoughts?



yep. put that in a shortened form that i can understand easily and i'll let you know what i think.

Ginger fury
i sing chaka khan songs while wearing my white stilettos
Wed 5th Sep '07 10:44PM
278 Posts
Ginger fury's Avatar
Member Since
5th Jul '06
Oh this debate always gives me a head ache!!

On the one hand I can see how Embryonic stem cells are incredibly plastic and therefore so much more useful and willing to change into more complex structures, and on the other I guess I'm a lapsed Catholic Po-lifer (for my sins). I don't want to be a pro lifer to be honest and I don't really think I am, but I'm indoctrinated !! However if I was to have a child with a debilitating or degenerative illness I'm pretty sure I'd be after me getting my unborn child some stem cells well prior to birth if it was congenital or genetic and I'd want the best!!

But Ohh the embryos - every life is sacred!!

I have to say I normally come down on the umbilical cord side as this seems to have shown some excellent results as far as I can see. It also solves some of the ethical issues, for me and has massive plasticity (even if it can be rejected).

I do suspect that one day they will have the breakthrough that they have promised and then like you say, thats natural selection out the window

Oh by the way you sounded like a professor yourself on that subject lol

Clara
Even red onions have a silver lining
Thu 6th Sep '07 10:32AM
838 Posts
Clara's Avatar
Member Since
27th Sep '04
This is a particularly strong issue in the Catholic church just now. Last weekend my priest gave a sermon on the subject.

It's a really tough one to call. I do believe that every life is sacred and that includes unborn children, from the moment of conception. (I've never had any kind of moral dilemma with the use of contraception, conception is the key point for me - not the opinion of all Catholics, I grant you.) For this reason my gut always screams no when any sort of research on embryos is mentioned.

However, as GF says, I've never been put in the position where my life, or the life of a relative or friend, depends upon such research. Therefore I really don't know how I would react and I cannot condemn the research because of this.

It's also why, although I would never consider an abortion myself, I would never condemn anyone else for making that choice. Also, at the present time I could never see myself having IVF, but then again I am not trying for a family or aware of any problems that I may have in doing so. Until I am faced with such a choice, I have no idea how I will react.

Sorry, gone a little off topic there. But it all seems linked, somehow.
 

Ginger fury
i sing chaka khan songs while wearing my white stilettos
Fri 7th Sep '07 12:23AM
278 Posts
Ginger fury's Avatar
Member Since
5th Jul '06
It's not off issue for a Catholic though is it, thats the point - there all interrelated topics.

I too have no issues with contraception and If my daughter came home pregnant aged 14, I'd no doubt try to march her down the clinic. But regarding my daughter, are they are just words?! Because I know they make sense.

I would really struggle myself however, to have one of those trips down the clinic! It just would not sit well with me. I still remember the Latin masses and can still sing in Latin even if I can't still talk in it!! I'm far too indoctrinated but I know my children are not, in spite of going to a Catholic college and all that jazz.

I have to say though if my child or grand child needed help from anyone or anything, I would never underestimate the the drive of maternal protection.

Didn't mean to be so heavy, I'll go squash myself with the fridge lol

Religion and logic rarely make a good combination!! It's a ecumenical matter lol (spelled incorrectly no doubt)



By the way someone has put a spell check on my posts and it's brill, now I can say more of what I mean!! So thanks to who ever did it

Mrsham
I lost my toes in a game of blackjack
Fri 7th Sep '07 7:47AM
505 Posts
Mrsham's Avatar
Member Since
5th Jan '07
Someone on a debate I've been following elsewhere stated, essentially, that the hybrid embryos could never be brought to term. Because of the animal cell used in the process, they would be rejected by any human mother's womb in which they were implanted, and terminated "naturally". Any one else know for sure one way or t'other?

The question therefore, for me, isn't the same as the abortion question -- whether a potentially viable human foetus should be terminated -- but rather different, namely whether a never-will-be-viable human embryo should be created for harvesting in this way.

I'll say straight away that I don't believe in the transfer at fertilisation of a soul to a human embryo. If I did believe that then the abortion / hybrid embryo questions become, as you say GF, essentially similar. I see the soul as being something that grows along with the body (in fact inseparable from the material that houses it i.e. I'm not a dualist. Don't ask me how I square that with a belief in God and the afterlife or you'll get a lengthy off-topic essay!). Essentially, I don't see the hybrid embryo, at the stage it's terminated, as being a human being in and of itself -- it has none of the complexity necessary to be a "person" -- whatever we take that to mean!

Nor does it have the potential to become a person -- for me this is pretty important -- so I come out in favour. (Interestingly I believe that researchers have been using human eggs until now, which -- I think -- means any resulting embryos had the potential of being viable if implanted a la Dolly! Not that anyone has tested this obviously. So from my perspective the ethics of the hybrid embryo are more clear-cut than the method researchers have been following until now anyway.)

This all rests on some slightly shaky assumptions so feel free to correct my second hand knowledge of the biology of this and I'll think again!

(There's the beginnings of a debate starting on the Ship of Fools that gave me much of the fuel for this post)
 

Mrsham
I lost my toes in a game of blackjack
Sun 9th Sep '07 8:45PM
505 Posts
Mrsham's Avatar
Member Since
5th Jan '07
Sorry to double post, but anyway:



Emo Squid was bold enough to comment:
On the other hand - and this applies to most areas of medical advancements - I'm left wondering where the balance between human intervention and the process of natural selection lies. I'm no authority on this what so ever, but so long as we blinkeredly continue to prolong/'improve' the lives of those around today, I can't help think we're paving the way for a much more complicated future. Yet, conversely, I harbour hopes that this kind of research will lead to a quantum leap in disease therapy - largely because cancer and heart trouble runs in the family and my uncle (a wonderful human being) is being tested for Parkinson's at the moment. It's very difficult to have a personal attachment to something and maintain objective, I guess.

Thoughts?



This is interesting; my gut reaction is that medical research shouldn't be influenced by any sort of social engineering. Medicine, it seems to me, is about caring for and improving quality of life for the rest of us, and society and politics -- and indeed medical researchers! -- have to try to keep pace with the consequences of that in a positive rather than a suppressive way. I agree that prolonging life doesn't necessarily equate to greater quality of life; but at the same time I think that stem cell research seems to be the best shot at improving the quality of life of the ever-aging population, and cracking some horrible diseases that are associated with old age. (But then I'm also biased!)

EDIT: and may have bought into the stem cell hype too much
 

Emo Squid
sanctus, sanctus, sanctus
Tue 9th Oct '07 4:01PM
624 Posts
Emo Squid's Avatar
Member Since
23rd Feb '07
Not quite stem cell research, but this story does involve antibodies that have been engineered from a single cell:

http://news.bbc.co.uk/1/hi/health/7035883.stm


Bookmark With: Post to DiggDigg   Post to DeliciousDelicious   Post to RedditReddit   Post to FacebookFacebook   Post to StumbleuponStumbleupon
Return To The Big Questions

Time Zone is Greenwich Mean Time You are Visible
Html Tags are On Smileys are On
Anonymous Posting is Not AllowedMagina is The Daddy