Serendip is an independent site partnering with faculty at multiple colleges and universities around the world. Happy exploring!

Sickle Cell Anemia

dchin's picture

Biology: Basic Concepts
Web Paper Assignment # 2
Sickle Cell Anemia
            The understanding of life at a small scale has revolutionized modern science for better and worse. One of the most infamous examples of a negative result is the manipulation of the atom, which led to the creation of the atomic bomb, and ultimately the death of millions of people. However, this same understanding of cells on such a miniscule scale has also led to the development of effective cancer treatments that have saved lives. Like so many other aspects of recent scientific progress that live in the grey, in-between area of ethics, understanding life at a small scale is a tool that can either be used for the overall good of humanity or cause harm to itself or other entities. Difficulties arise because people have varied opinions on what is helpful or harmful, and these opinions change as the attitude of a society changes. All this debate over how the understanding of life’s most basic building blocks should be applied presupposes that we have a right to tamper with our constituent parts. Our large ability to control and affect the environment around us has fostered the societal belief that we are at the top of the food chain, when in actuality we are composed of just as improbable an assembly as any other organism. Life as a whole will continue to exist long after humanity passes on, which is a tribute to the resilience of Mother Nature. Therefore, is it acceptable for us to try to change what Mother Nature has given us? Many of the ailments that we seek cures for can be viewed as natural methods of population control. It is a natural response to humanity’s continuing encroachment on all the resources that Earth has to offer. An interesting lens through which we can explore this question is sickle cell anemia.
            Sickle cell anemia is a disease that takes place at a very small scale for which humanity has not found a cure. Hemoglobin is a protein that carries oxygen from your lungs to the rest of your body. (1) There is only one difference between normal hemoglobin and sickle cell hemoglobin: one amino acid out of 287. In normal hemoglobin, the amino acid codes for glutamic acid, but in sickle cell hemoglobin, the amino acid codes for valine. (2) As a result, the body produces red blood cells that are shaped like sickles and do not flow through blood vessels well. Instead, the sickle-shaped cells block blood vessels, subsequently stopping the transport of oxygen. On a larger scale, this results in anemia, stroke, infections, and pain in hands, feet, stomach, back, or chest. There is only one known cure for this disease, although it is manageable with care. Those diagnosed with sickle cell anemia at a young age must be immunized, but as carriers of the disease age, their only course of treatment is to learn how to manage the symptoms. (3) Despite the current lack of treatment, there is a lot of innovative research taking place. One such project involves the use of stem cells to cure sickle cell anemia. The experiment was performed successfully on mice with the disease. Two aspects of this research were especially significant to me because they tampered with so basic a part of human biology that my initial reaction was one of discomfort. Scientists have converted skin cells into “induced pluripotent stem” cells by introducing the skin cells to viruses that were designed to make them identical to embryonic stem cells. Then, they cut out the parts of DNA that result in sickle cell anemia, and replace them with normal DNA. (4) A proven method of treatment is bone marrow transplantation. It is, again, the only known cure, but it comes with the risk of death if complications occur. (5)
            These two actions caused such discomfort because they modify human biology on such a small scale. Perhaps this should not even be quite as shocking as it is, but there is something very unappealing about not only forcefully changing your DNA or bone marrow, but also using a virus as a tool to achieve something positive. The ease with which researchers can simply switch out a part of your genetic makeup invokes thoughts of megalomaniacal scientists conducting Frankenstein-ian experiments. The myriad number of ways that using a virus, something with a connotation of harm and destruction, to cure sickle cell anemia can end horribly is simply daunting. While it is true that this could prove to be the cure, and end up saving millions of lives, I cannot help but feel that there must be a line drawn somewhere. There must be a respect for the preservation of our humanity, because otherwise, where will the experimentation end? We are a very improbable assembly of atoms, but since the majority of us are the way we are, is there nothing to be said for the beauty that lies in our original forms? It is practical to utilize the knowledge that we gain of life at small scales, but this must be tempered with a commitment to ensuring that the pursuit of progress does not result in the loss of our humanity. To take a harsher view, humanity will not survive indefinitely. All the cures and stresses that we put on the environment are simply measures to delay our inevitable passing. Even the formation of sickle cell hemoglobin is an improbable assembly that nonetheless has occurred and the fact that the problem lies with so basic a structure as a blood cell, possibly says that attempts to find a cure are only delaying the unavoidable triumph to Mother Nature.


Paul Grobstein's picture

sickle cell anemia: past and future

New knowledge is indeed a two-edged sword.  Advances based on it seem inevitably to good perceived as valuable in some contexts, not so in others.  I wonder whether recognizing that may be important in thinking about the value of new knowledge, as well as when/how to make use of it.  In this context, its interesting that sickle cell anemia itself seems to be the result of a mutation that was beneficial in some contexts but is lethal in others.