Sedge Lucas
10/21/11
Period 5
Sickle Cell Treatment, Gene Therapy or Bone Marrow Transplants
Sickle Cell disease or anemia is a inherited genetic disorder with the
blood. In sickle cell anemia, the HBB gene inside the hemoglobin molecule, is
mutated, and as a result of this, the red blood cells in the victim become hard
and sickle shaped. This sickling of the blood cells can cause, anemia, because of
sickle cells breaking down prematurely, jaundice, episodes of pain when the
sickle cells get stuck in a vein or artery, pulmonary hypertension, which can
lead to heart failure. Sickle cell disease is one of the most common blood
disorders, and millions of people are affected by it. It is estimated that around
70,000-80,000 Americans have sickle cell disease, and around 1 in 500 African
Americans and 1 in 1000 to 1400 Hispanic Americans have this disease. As this
disease effects so many, multiple studies have been done on it, and from these
studies, methods of treatment and possible methods of curing the disease have
been found.
The many symptoms of sickle cell disease can be treated in a multitude
of ways. Good hydration, the use of pain medication (for pain attacks) and the
drug Hydroxyurea, red blood cell transfusions, the use of penicillin and up to
date immunizations (as the sickle cell disease effects the immune system) can
all be used to treat both the primary and secondary symptoms. While these
methods can be quite effective for treating the symptoms, none of them truly
cure the patient of the sickle cell anemia. There are two main ways that sickle
cell anemia can truly be cured though. The first way that sickle cell anemia can
be cured is through the use of bone marrow transplants. The second way that
sickle cell anemia has been tested to be cured on mice, is through the use of
gene therapy.
The first way that sickle cell anemia can be cured is through bone
marrow transplants from a donor to the sickle cell victim. These bone marrow
transplants can cause the new normal red blood cells to be created by the
donated bone marrow, and as a result of this, the person with sickle cell will
essentially be cured. While bone marrow transplants can be effective, the donor
must match the patient genetically (usually a sibling or relative), and there are
many possible complications that can occur after the surgery, ranging from pain
to serious infections and internal bleeding. The second lesser know method of
curing sickle cell disease is through gene therapy. Through the use of a
harmless virus, scientists have been able to add a gene into mice who had the
sickle cell disease. In the mice, the addition of the gene in the hemoglobin
caused the mouse to have none of the symptoms of sickle cell anemia, and
essentially cured the test mice of Sickle cell disease. While this treatment has
only been done on lab mice, as they are mammals scientists believe that this
treatment could work for humans with sickle cell disease too.
Firstly, According to Chen, Y. (2011) for the curing of sickle cell anemia
by the use of bone marrow transplants, this method is a reliable way of
“replacing damaged or destroyed bone marrow with healthy bone marrow stem
cells” and by doing so efficiently cure sickle cell anemia. While this method has
been tested multiple times, and many people have been cured of their sickle cell
anemia, according to About sickle cell anemia, (2011), “the marrow must come
from a healthy sibling donor, and the procedure has many risks” ranging from
infections, internal bleeding, to heart damage. On the other hand, curing sickle
cell anemia using gene therapy, According to Gene therapy corrects sickle cell
disease in laboratory study (2008) “Using a harmless virus to insert a corrective
gene into mouse blood cells, scientists at St. Jude Children's Research Hospital
have alleviated sickle cell disease pathology”. While the mice were basically
cured, or at least all their symptoms of sickle cell disease left them, this
treatment has only been tested on mice, and therefore while mice and humans
are both mammals, humans can not actually be cured as of now from sickle cell
disease through the use of gene therapy, according to Gene therapy corrects
sickle cell disease in laboratory study (2008).
Overall, the use bone marrow transplants to treat sickle cell anemia
was effective in a quite a few cases, but the restrictions on those who could
donate, and the possible side effects make the use of bone marrow transplants
to treat sickle cell anemia not ideal. On the other hand the use of gene therapy
to treat sickle cell anemia, showed few or no side effects, and effectively would
be available to all people with sickle cell anemia, but the use of gene therapy to
treat sickle cell anemia has only been used on mice, and therefore the use of this
treatment is not available for humans yet. As the use of bone marrow
transplants to treat sickle cell anemia is the only method of curing the disease,
it is the most effective method of treating sickle cell anemia at this time.
Bone marrow transplants take the bone marrow from a healthy donor,
or fetal stem cell, and transplant that into a patient with sickle cell anemia.
Contrary to this, gene therapy is simply where a gene is put into a virus (all of
this done inside a laboratory), which is inserted into a human with sickle cell
anemia. From an moral stand point, treating sickle cell disease by using bone
marrow transplants from siblings, or fetal stem cells, involves taking the cells
from a living being and attempting to save a patient with sickle cell disease,
while taking, and possibly harming the donor. On the other hand the use of
gene therapy to treat sickle cell disease seems morally better, as the genes, and
the virus that would be injected into the patient with sickle cell disease, could
be made completely in a lab, and no one would come to harm, and doctors
administering this treatment could feel they were doing the morally correct
thing, if this method of treatment was perfected for humans. One possible
problem with this treatment though, would be that test would have to be done
on animals to perfect it, and that would be morally wrong.
According to Chen, Y. (2011) there are two main ways of treating
patients with sickle cell disease. First of all, there is an allogeneic bone marrow
transplant, in which the “Stem cells are removed from another person, called a
donor”. Secondly, there is an umbilical cord blood transplant, in which stem
cells from a newborn baby’s umbilical cord are removed, and then administered
to people with sickle cell disease. This means that while an umbilical cord blood
transplant would not harm the donor, as the umbilical cord’s stem cells would
simply be used, if the allogeneic bone marrow transplant method was used, the
donor or patient could be harmed in some way, as according to, About sickle cell
anemia, (2011), “the procedure [of a bone marrow transplant,] has many risks.
As for gene therapy, according to, Gene therapy corrects sickle cell disease in
laboratory study (2008), the virus used to insert a corrective gene, would be
“harmless”(therefore not harming the mice), and also, this corrective gene
would be made in a lab, and therefore no one would be harmed by this
procedure.
Using a bone marrow transplant to cure sickle cell anemia in some
cases can have negative side effects on the donor and the patient with sickle cell
anemia, but on the other hand, using gene therapy would cause no negative side
effects (even for mice) and would not involve a donor being injured or even
having to donate anything, other than perhaps money for the treatment, to the
patient with sickle cell anemia. According to About sickle cell anemia, (2011),
the treatment of sickle cell anemia with a bone marrow transplant has many
risks, of which according to Chen, Y. (2011) include, Infections, pain, internal
bleeding, heart damage, and stomach problems, for the patient. Also, there are
possible complications for the donors, and with so many complications, and
possibilities of error, it may not be morally right to subject people with a disease
that is not fatal to this treatment. On the other hand, according to Gene therapy
corrects sickle cell disease in laboratory study (2008), the treatment of sickle
cell disease with gene therapy “alleviated sickle cell disease pathology” in mice.
As using gene therapy to treat sickle cell anemia, would not hurt the patient
with side effects, and there would be no need or a donor to be possibly injured,
and also, even the test mice would not be injured by the treatment, it would
seem that the use of gene therapy to treat sickle cell anemia is morally well
found.
While it has been determined that from a moral standpoint gene
therapy is a better cure to sickle cell disease, as there are many fewer risks and
side effects with gene therapy than with bone marrow transplants, from an
economic standpoint, the situation may be very different. From an economic
stand point though, treating sickle cell disease using bone marrow transplants
is quite cheap and could be afforded by many people as it is not that new of a
treatment, and it has been in use for a longer time. Not only is a bone marrow
transplant cheap for the service being done, but also, gene therapy as it is a very
new type of treatment, involving the work of quite a few scientists, the cost for
treatment of sickle cell disease using this gene therapy would be very high, and
not economically friendly to everyone.
According to Cost of bone marrow transplant (2010), “An allogeneic
transplant may range from $150,000 to $200,000”. This 150,000 to 200,000
dollars that would be spent, would be a one time thing, and if everything went
as it should, and there were no side effects, it would only cost the patient with
sickle cell anemia this relatively small sum of money, considering the treatment
being given, to be cured completely of their disease. On the other hand,
according to Maltzman, J. D. (2004)the price of gene therapy, as it is such a new
and complex treatment, is “exuberantly expensive and therefore not accessible
by all”. Also According to Lane, A. (2010) it is estimated that the treatment for
just the first year would cost 100,000 dollars, and to fully cure the disease in
humans, most likely multiple treatments would have to be done, amassing to
great sums of money being spent on multiple years of attempting to cure the
disease using gene therapy.
From an economic standpoint, a bone marrow transplant to cure sickle
cell disease is much more cost effective than using gene therapy to treat sickle
cell disease, this is the opposite of these two treatments effectiveness from a
moral standpoint. As a bone marrow transplant only costs 150,000 to 200,000
dollars, for a one time treatment that with no side effects, would cure the
patient of sickle cell disease completely, it is much more cost effective than
having to pay 100,000 dollars for multiple years, to use gene therapy to treat
sickle cell disease. The bone marrow transplant would with only one treatment
of 150,000 to 200,000 dollars cure the patient of sickle cell disease, and from an
economic standpoint be much more cost effective, and therefore better for many
people, than treating sickle cell anemia using gene therapy.
The use of a bone marrow transplant is a method of curing sickle cell
disease, that there are a few moral issues with. First of all, a bone marrow
transplant, has many possible side effects for the donor, from the surgery to
extract the stem cells or bone marrow, and for the patient who can have many
side effects ranging from simple ones like pain, and stomach problems, to
internal bleeding, and heart damage. The number of problems with using a
bone marrow transplant to cure sickle cell disease raise a moral dilemma over
whether it is worth it to use this treatment on people who have non-fatal
diseases. As for the use of gene therapy to cure sickle cell disease, the moral
implications are that, no one would be hurt or even would have the possibility of
being injured in the slightest as a result of this treatment, unlike a bone
marrow transplant, and therefore using gene therapy, with its lack of possible
side effects would be morally better than the use of bone marrow transplants as
a cure for sickle cell disease.
The limitations from a moral standpoint for a bone marrow transplant
are the many possible side effects on the donor or patient, and also lack of
compatible donors for this procedure to take place. As the procedure has so
many risks, and so few people are able to complete it safely, and effectively, the
moral question is with all these limitations, is it right to attempt to cure people
using a bone marrow transplant, if their disease is not fatal. As for the
limitations of gene therapy, successful tests have as of lately only been done on
mice, and therefore, while the implications are the treatment would work on
people, the limitations of not being tested on humans are in the mix.
Overall, from a moral stand point, it would seem that if the use of gene
therapy for humans, not mice could be perfected, it would be better morally, as
people would have a cure that would have no side effects that could make
disease they have even worse. The gene therapy, as it has no known problems
now would be ideal, and would involve no moral issues over the possibility of
making someone’s disease worse, as is possible with a bone marrow transplant.
As gene therapy for humans has not been perfected yet, the bone marrow
transplant, while it does have many possible negative side effects, is the only
method of curing sickle cell disease currently. So until human gene therapy has
been perfected, people with diseases will have to live with the moral dilemma of
whether or not to attempt to cure your disease with a bone marrow transplant,
when that transplant could make your disease even worse.
From a economic stand point, there are many implications of which
treatment, a bone marrow transplant, or gene therapy would be more cost
effective. The implications from multiple articles are that a bone marrow
transplant, with no side effects, would cost from 150,000 to 200,000 dollars, and
no more, as with luck the disease the patient would be treated for would have
been cured by the transplant. On the other hand, it seems that as gene therapy
is a relatively new idea, and it takes the work of quite a few scientists to make
the virus to inject into the patient, estimates are that it would cost at least
100,000 dollars for the first year of treatment, and it is assumed that multiple
years of treatment would be in store for those who had gene therapy to cure
their disease. The implications of many articles are that bone marrow
transplants while less reliable, and with more side effects, would cost quite a lot
less than gene therapy to cure sickle cell disease.
There are quite a few limitations, in an economic context, to curing
sickle cell disease with both methods. First of all, with the use of bone marrow
transplants to cure sickle cell disease, while the initial treatment with no side
effects is not terribly expensive, the possible need to cure the side effects of a
bone marrow transplant, could make the cost of getting a bone marrow
transplant much higher than 150,000 to 200,000 dollars. As for the use of gene
therapy to treat sickle cell disease, as gene therapy has only been done to cure
mice of sickle cell disease, there are only estimates at the cost of treatment for
humans, and therefore the real cost if a gene therapy is made for humans could
be much higher than estimates, and therefore only be available to the very rich.
Overall, from an economic standpoint, the use of bone marrow
transplants to cure sickle cell disease seems to be much more cost effective than
the possible use of gene therapy for humans in the future. While bone marrow
transplant’s possible side effects could cause the cost of treating sickle cell
disease with bone marrow transplants to rise, the high cost, and possibility of a
higher cost, and multiple years of paying for gene therapy make bone marrow
transplants while not the safer or less risk free way of treating sickle cell
disease, the cheaper, or more cost effective way. All in all, it seems that treating
sickle cell disease using a bone marrow transplant, or gene therapy both have
good parts to them, but problems as well. While bone marrow transplants have
many possible negative side effects they are cheaper than gene therapy which
has many fewer side effects. Overall if the money is available to the patient, and
the technology is available, gene therapy is the safer, and more reliable option,
but to those who do not have enough money to get this finer way of curing sickle
cell disease, only have the cheaper, but negative side effect full method of bone
marrow transplants.
References
About sickle cell anemia. (2011). Sickle cell anemia. Retrieved from
http://rarediseases.about.com/od/rarediseasess/a/sicklecell.htm
Chen, Y.-B. (2011, March 17). Bone marrow transplant. Retrieved from
http://www.nlm.nih.gov/medlineplus/ency/article/003009.htm
Cost of bone marrow transplant. (2010). National bone marrow transplant link. Retrieved
from http://www.nbmtlink.org/resources_support/rg/rg_costs.htm
Gene therapy corrects sickle cell disease in laboratory study . (2008, December 4). Science
daily. Retrieved from http://www.sciencedaily.com/releases/2008/12/
081203184643.htm
Lane, A. (2010). Healing the wounds that never heal. In Access to gene therapy. Retrieved
from http://www.scu.edu/ethics/publications/iie/v10n1/wounds.html
Maltzman, J. D. (2004, February 22). Gene therapy: Where are we today. Retrieved from
http://www.oncolink.org/resources/article.cfm?c=3&s=38&ss=154&id=348