Sunday 24 August 2008

Stem Cell Ethical Concerns

This particular post should be read after (at least!!) reading the previous 3 posts - Stems Cells 101, & the Potential Impact of Stem Cell Research Part1 & Part2.


I shall try to outline some of the concerns surrounding this issue. Again, this is done in a rather over-simplified manner.


Of course, I think almost everyone involved or interested in the whole debate, is hoping that the recent research where adult stem cells, or even cells harvested from the umbilical cord will prove to be a successful route in the future. This technique should remove many (but not quite all) of the concerns that people have on the issue. I promise you that no scientist is choosing to research this area because of the ethical issues, or merely to make use of spare blatocysts that there may be in his lab. Every researcher I have met in this field is fully aware of the sensitive nature of the research. Certainly none of them are the evil mad scientists, that some sections of the popular media try to portray them as! (Well OK, I cannot comment on some of the North Korean labs…)


The main concerns are:

  • Human embryonic stem cell research involves the destruction of a blatocyst, which some people regard as a human life.
  • Some people have an issue with creating a blatocyst with the sole intention of destroying it.
  • A concern is that this research could lead to the exploitation of women, as more and more donor oocytes may be needed.
  • Some people object to the mixing of human and non-human genetic material in the research.
  • Some sections of society even have objections to any advances in not only stem cell research, but genetics, molecular biology, and many other similar medical interventions are manipulations which undermine human dignity.
  • There are other concerns, certainly but I hope this touches on the main ones.

Any research on human embryos is going to raise profound questions about the status of the human embryo, the extent to which it is justifiable to use human embryos to expand knowledge and ameliorate human suffering, and the conditions under which these goals may be pursued. Many people hold the view that a human embryo (of any stage) is morally equivalent to a human life. Some claim that any manipulation of a human embryo undermines human dignity. These are philosophical views which should not just be ignored. However, these philosophical views do not always manifest themselves culturally in our societies. A natural miscarriage (which, I have had the misfortune to witness) is a harrowing experience, but we do not conduct a funeral afterwards. Similarly, for most couples, the excess blatocysts from IVF treatments can be disposed of without any need for ceremony or specific interventions that we may feel appropriate for, say, the death of a child. Many religions do not recognise the human embryo as human life until a specific stage (around 40 days after conception).


I do feel that any discussion on the ethics of stem cell research should respect these deeply held views. But I do not feel that these, alone, should bring all research in these matters to a complete halt, as the potential benefits to so many people are so huge. But I do feel that these views should assist us in developing workable ethical codes, which take into account the special status of the human embryo, and try to protect that status in a serious manner.


An excellent overview can be read at

http://books.nap.edu/openbook.php?record_id=11278&page=47

Potential Impact of Stem Cell Research (Part 2)

Right, so we have covered what stem cells basically are (Stem Cells 101), and I touched on their potential impact in the next post Potential Impact of Stem Cell Research Part 1. Now let's look at the more controversial issues of cloning. I think this is the area which is most misunderstood, and seems to cause most problems for many people.

There are two distinct subjects to cover:
a. Therapeutic Cloning.
b. Reproductive Cloning.

Therapeutic Cloning
This is where cloned tissue is used to "grow" replacement organs for people who have sustained damage to their organs (through disease, or injury, for example). It so happens that this month (August) is organ donors month. I would encourage everyone to consider signing up for organ donation. Discuss it with your family, as obviously your decision will effect them. But organ transplants are becoming more commonplace (as we know, the first heart transplant was performed in SA). Transplants are held back for 2 main reasons; the availability of organs, and also the fact that the human body tries to reject foreign tissue. To get around the second problem, the recipient has to be pumped full of very strong anti-rejection drugs (which also leaves the person with vastly weakened immune systems). This can often lead to complications, other infections and death. Our knowledge is increasing in this though. The concept of therapeutic cloning is to use (ideally stem cells derived from that person, from potentially umbilical cord cells, or from adult stem cells) tissue that has been grown from stem cells that have had the recipients own DNA introduced into them (by the use of Somatic Cell Nuclear Transfer - SCNT). This would negate the rejection problem. Recently, in Imperial College London, a heart valve was produced and transplanted into a patient. Because stem cells have the ability to grow into any cell, then it is hoped that almost any tissue or organ could be produced in this manner. The potential of this is huge, and could dramatically improve the survivability of people who are severely injured in car accidents, properly functioning pancreases may be grown for people with diabetes, brain tissue producing the right amount of dopamine for people with Parkinson's Disease, new kidneys for people in renal failure, eye tissue & retinas for people with different conditions causing blindness such as RP, the list is very long… Of course we have a long way to go, and it may well be that we have some more huge hurdles to overcome. The mass media has overplayed the timings (and ease) of this science. It is hugely complex, and the likely benefits are still some time away.

Reproductive Cloning
Reproductive cloning is where a completely genetically identical embryo is produced. Think Dolly the sheep (whose stuffed body can be viewed in the Museum of Scotland), or Booger the pitbull. Again, I feel that the mass media are at fault in badly reporting the issues around reproductive cloning, with visions of armies of identical Aryan peoples. The media has also falsely reported that human cloning has already happened in some countries, but a more detailed look at the evidence would suggest that this is very unlikely. Reproductive cloning is also fraught with complex problems (aside from the ethical considerations). There is also a complete misunderstanding about what a clone is. A clone is a genetically identical twin. But this would not mean that the clone would think exactly alike to the donor. But, as we know in the nature / nurture observations, genes are only part of the make up of any characteristics. Identical twins, that have been separated at birth, while still displaying obvious visual similarities, can often grow up to have completely different characters, molded by the environments in which they grew up in. Dolly would not have had the same thought processes as her donor animal. Very few people see any benefit of producing human (or indeed any animal) clones, as there is no increase in the genetic profile. There is the theoretical possibility of producing a reproductive clone with the sole purpose of harvesting donor organs, but there are obvious moral & ethical issues to this. But nevertheless, it is important that any discussion on ethics and morals around this subject must also consider this possibility.

Potential Impact of Stem Cell Research (Part 1)

Stem Cells 101 gave a very brief, simple look at stem cells. Now we will look at the possible areas in which they may be used. I really want to unpack this before touching on the ethical issues. In this post I am concentrating on impairments and diseases. Part 2 will look at the potentially more contentious issue of cloning.

It is important to realise that while there are applications were adult stems cells are being used in medical procedures to good effect (in particular bone marrow transplants to treat Leukemia, and one of my friends is alive today because of that particular procedure!), presently there are no medical procedures being used based on Embryonic stem cells. So is all this noise a waste of time? Well, no. Research is still in the early stages. Indeed the first time that human stem cells were first derived was only in 1998. In the 10 years since then a lot has been found out, but this has also been hampered by restrictions, many political in nature. Certainly no one is doubting that this is a complex part of medical science. The mass media has not helped, by some of the very poor reporting, and exaggerated claims that they have fed the general public. Even if this research will produce cures & applications (which I am confident they eventually will), these are not "just around the corner", as has been reported in many instances in the previous decade. The reality is that I shall keep my wheelchair for the time being, and my father is probably too old for him to receive any cure for his Parkinson's Disease in time.

But the potential of stem cell research is enormous. Not only for the number of diverse conditions that may finally have a cure (or even a prevention), but also because of the nature of many of those diseases. Medicine has made some amazing advantages over the last century, and probably each of either would be, or have a close family member who would have died, if it were not for some medical intervention or other. Certainly 75% of my immediate family would be dead, including me. But there are still many really serious conditions and impairments that we just have no answers for yet. Many of these have a profound effect on peoples' lives. The possible diseases and impairments that stem cell research has the potential to effect includes (this list is not meant to be exhaustive!):

  • Neurological
    • Parkinson's Disease (think Michael J Fox, Muhammad Ali)
    • Spinal cord injuries (Think Superman…and...dissol!!?)
    • Retinal disorders (Stevie Wonder)
    • Multiple Sclerosis (up to 150 out of every 100,000 of the population)
    • Alzheimer's Disease (26.6million people worldwide think Ronald Reagan, Terry Pratchett), although it has to be said that some recent research in this particular field is painting a less promising picture than we had thought...
    • Motor Neurone Disease (Prof Stephen Hawking, David Niven)
    • Muscular Dystrophy
    • Huntington's Disease
    • Spinal Muscular Atrophy
  • Others (Blood & Pancreas mostly)
    • Leukemia (2% of all cancers)
    • Sickle-cell Anemia (especially important to us in sub-Saharan Africa)
    • Immunodeficiency (including HIV & AIDS)
    • Lymphomas (5% of all cancers)
    • Lupus (Michael Jackson, Elaine Paige Seal)
    • Arthritis (Nelson Mandela)
    • Bone Marrow Failure
    • Diabetes (171million people or 2.8% of the global population, and rising, rapidly)

Of course, I am not claiming for a moment, that stem cell research will find absolute cures for the above, or any of the above. That is a common mistake made by the mass media. It may be, that some of the hurdles that researchers are finding out about, that they are insurmountable. But the research is looking very exciting in many of these different areas. I doubt we shall see any cures in widespread use soon. The best estimates seem to be looking 3 - 10 years ahead. That is also sometimes used as a argument against stem cell research; they ask "where are the cures?" This is not unreasonable, but the reality is that we do have some (small) cures and advances already, but also that this whole area of research is very complex, and by the nature of the research much of it is slow moving. Remember human stem cells were only first isolated in 1998…a mere 10 years.

Next post will be looking at the more contentious (and I would suggest less well understood) issues of cloning, both therapeutic and reproductive cloning. Only then, once we can agree some baselines, should we begin to think about some of the ethical issues around this research.

Saturday 16 August 2008

A nice quote to get you thinking

I happened across this wonderful quote by Susan Wendell, from her book "The Rejected Body: Feminist Philosophical Reflections on Disability". I think it is worth sharing:

Not only do physically disabled people have experiences which are not available to the able-bodied, they are in a better position to transcend cultural mythologies about the body, because they cannot do things the able-bodied feel they must do in order to be happy, ‘normal,’ and sane….If disabled people were truly heard, an explosion of knowledge of the human body and psyche would take place.

Monday 11 August 2008

Stem Cells 101

This post is an attempt to explain what stem cells are, and the differences between the different types. I am not going to touch on the ethics of stem cell research in this post, but leave that for a later discussion. I do think it is important that people understand what a stem cell is before they are able to make a judgment call on the ethics surrounding the subject. That may sound obvious; but experience has shown me that again, and again, people (including very powerful people) will make a really serious decision, without fully understanding the issue behind stem cells.


I am also going to try to keep this short and therefore I may be accused of over-simplifying. I apologise in advance for that, and should be able to give more information if anyone requires it. I am not going to talk about the research at this stage either. It is just looking at the stem cell themselves, what they do, and where they come from.


Almost all living organisms have stem cells. The name comes from the fact (like a plant) these are the stem, that have the capability to produce different types of cells & therefore tissue. They are of course the cells which allow animals to grow (both in the womb, and later in life). They are also the cells which allow our bodies to repair damage. So if you want to see them at work, then you can cut yourself. Eventually the cut will heal over, and new tissue will be grown to heal the cut. Clever things…we would be in trouble without them.


Now there are different types of stems cells, and they are identified by the number of different types of tissue that they are able to produce.

  • Totipotent - can produce any cell within the body
  • Pluripotent - can produce almost any cell of the 3 germ layers.
  • Multipotent - can produce any cell of a particular family of cells
  • Unipotent - is only able to produce one type of cell

The potentially most useful cells are the ones that can produce the most type of cells - the first 2 (actually the focus is mostly on pluripotent) groups. And indeed it is these cells (and how they are harvested) that cause almost all the controversy.


In humans, pluripotent stem cells are taken from blastocysts, which are 3-5 day old embryos. The embryos are provided by fertility clinics. When females are receiving certain fertility treatments then they are given drugs to cause them to super-ovulate (or to produce many eggs). These are removed from the uterus and fertilised with the sperm. In other words, these embryos have never been inside a human body and would never go on to produce a foetus. If they were not to be used for stem cell research then they would be discarded, thrown out with any other organic waste.


A really exciting recent development from 2 separate pieces of research from last year, is the possibility to use adult multipotent skin stem cells, and alter them so that they could become pluripotent. Should this technique be fully successful, then it may remove almost all of the objections that people may have against stem cell research.


In the next post I would like to discuss the different research areas, and the lists of diseases / impairments / medical advantages that may be possible through this research. I think only when there is a full understanding of the facts, and issues that we can then go on to discuss the ethics.

Sunday 3 August 2008

Accessibility

Is your house accessible? Probably not. A recent survey in the UK found that 98% of all new, privately built dwellings are inaccessible (to wheelchair users). My anecdotal (therefore untrustworthy) experience, would suggest that that figure would be similar here in SA. What about your place of work? Or you local restaurant / café? What about your place of worship? Cinema? Doctor's surgery? Post Office?


So let's assume that your house is inaccessible. So what? No one in your house is disabled, and you certainly would not entertain the idea of inviting me around!!! Why go to the expense of making it accessible when it will never have a use?


Great question. Well, here comes the answer. A recent piece of research in the US (yes, I know all these are overseas figures, and things are different here…but please bear with me), has some fascinating findings. They predict that by 2050 (due to aging populations etc.) that 21% of all households will have at least one resident with a “long-lasting, severe mobility impairment” . Therefore (as people move houses) there is a 60% chance that any house will have to accommodate a long term disabled occupant, during the lifetime of the dwelling. However the figures are even more compelling when both short term impairments (such as injuries) & visitors are taken into account - they estimate that the figure rises to 93%.


The interesting point is that the trend towards accessible housing (so called lifetime housing) is being driven by the insurance industry in terms of cost saving. It is much more cost effective to design a house from the outset, to be accessible, rather than have to bolt on later. The sort of figures that are generally accepted is that to design any facility to be fully accessible from the outset adds 0.2% to the capital costs. Later adaptations can be as high as 10%.


It is not expected that every part of every house would be fully accessible (although that would be nice!), rather there are 3 main issues:

  1. At least one level entrance into the dwelling (can be front, back or side).
  2. All doors on the main floor, all doorways wide enough (>800mm) for easy access.
  3. At least an accessible half (but preferably full) bathroom accessible on the main floor.

The bottom line, is that it makes financial sense to design, and build our houses (and all other built environments, by extension) to be fully accessible to all. Any of us may benefit from this accessibility one day…indeed, one could suggest that we all hope that we live long enough that we will benefit.


The research paper can be read here.

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