Ethics of Stem Cell Research

illustration of stem cells

Submitted by Büsra Elkatmis to fulfill the ethics in science requirement for the Young Scientist Program at BMSIS.

What are stem cells?

Cells are the smallest known building blocks of living organisms. All of the cells in the human body have different functions. For example, white blood cells fight infection in the body while red blood cells carry oxygen, and heart muscle cells make the heart beat while neurons are used to transmit signals through the body and for the functions of the brain. On the other hand, stem cells are special cells with self-renewal and differentiation functions. Thanks to self-renewal property, stem cells can divide and produce more stem cells [1].

They are known as “undifferentiated” cells, which means that they can convert into specialized cell types. Stem cells can be classified according to how much they can differentiate into new cell types. The four main classifications are: totipotent, pluripotent, multipotent, and unipotent. Totipotent stem cells can turn into any other cell type. For example, the zygote, which is a fertilized egg cell, and the cells of the embryo up to the eight-cell stage are totipotent cells. These cells can form a complete and normal individual in the womb.

Pluripotent stem cells have the potential to differentiate into almost all cell types. For example, embryonic stem cells are formed from the inner cell mass of the blastocyst, which is a later stage of embryonic development.

Multipotent stem cells can differentiate into small groups of cells. For example, somatic stem cells are multipotent. This means that their differentiation potential is limited to a number of related cell types. Also, mesenchymal stem cells can be an example of multipotent stem cells. They have the potential to differentiate into cartilage cells, bone cells, and muscle cells [2]. The neural stem cells originate from the central nervous system. They can differentiate into nerve cells. The hematopoietic stem cells are another type of multipotent stem cell. They can differentiate into white blood cells and red blood cells.

Lastly, unipotent stem cells can only produce one type of cell. Even though they have a quite limited differentiation capacity, they’re still stem cells because of their self-renewal property. In this concept, they can maintain the undifferentiated stem cell pool as a result of this property.

Beyond these four main classifications, newly discovered induced pluripotent stem cells (also called iPS cells), are somatic cells that have reverted back to pluripotent stem cells under laboratory conditions.

Ethical Questions About Stem Cell Research

Stem cell research is an open area to scientific development and has the power to treat people with destructive diseases such as Parkinson’s, spinal cord injury, and more. For example, stem cell transplantation can be a good treatment for nervous system injuries, because they can maintain the function of damaged cells or tissues [3]. Despite this, there have been ethical questions raised as to the nature of stem cell research. One major question arises because of the methods used to obtain embryonic stem cells that in turn destroy the embryo.

Some people support that although the embryo is still under development, it is considered a potential person. The major problem with this is that the personhood criteria cannot be fully defined. It is claimed that the embryo should have respect and dignity since it would be human even if it did not have human characteristics yet. Others support that the fertilized egg is only an organic material just like our body parts until it can survive independently. If we destroy the blastocyst before it is attached to the womb, it cannot be mentioned of any harm or destruction, as it has no faith, desire, expectation, and purpose. Although both sides of the debate are interested in protecting human life, the position of the human blastula causes ethical problems [4].

Embryonic stem cells are obtained from cells within the blastula, one of the early stages of human formation. Just before the fertilized egg is implanted into the wall of the womb, it turns into a blastula that can survive for a short time. Blastula are harvested, isolated, and cultivated in a laboratory to use in stem cell research. They may even believe that when the egg is fertilized by sperm naturally or in vitro, personhood begins for blastocysts. Therefore, a moral dilemma arises in embryonic stem cell research.

Ethical Approaches to Stem Cell Research

Deontology Ethics Approach

The deontological approach is symbolized by Immanuel Kant’s principle of the Categorical Imperative, which underlined that persons must be treated as ends rather than as means. Individuals, as expressed in the Declaration of Independence, have been “endowed by their Creator with certain unalienable rights, that among these are life, liberty and the pursuit of happiness.” This argues that a person’s life cannot be sacrificed to achieve better things. Some people who assume both a deontological approach and the position that human life begins at conception may then argue that blastocysts are persons who have rights [5]. According to such a position, the destruction of the blastocyst to obtain stem cells is unethical.

During in vitro fertilization, many spare embryos are created that will not be implanted within the womb. These spare embryos may then be used in stem cell studies. This may also be incompatible with Kant’s Categorical Imperative ethical perspective for someone who believes that human life begins at conception since the destruction of these spare embryos to obtain stem cells means sacrificing human life. Proponents of this position may argue that spare embryos are still persons. Another important point here is stem cell lines. The use of stem cell lines that were created by destroying blastocysts is morally wrong from the Categorical Imperative standpoint because it represents the act of destroying human life.

However, some who argue from a deontological perspective while also supporting the concept that human life begins at conception may actually consider it ethical to use stem cell lines in research because they suggest that stem cell lines were created in the past and we can’t change that now. However, those arguing from that position may still be against creating new stem cell lines.

What about those with the deontological perspective, but who do not consider human life to begin at conception (and thus the blastocyst to not be a person)? In such a case, even though they accept the Categorical Imperative, they may see there being no personhood rights for blastocysts, and so no issue with recovery of stem cells at that stage. Meanwhile, for those who take such a stance, they may hold positions that human life begins at a variety of later stages of development (such as the development of the primitive streak or even at birth).

In either case (human life beginning at conception or at a time later in development), some will still take that position that even if it can be argued that blastocysts are not yet human, they are still part of human life, and thus they may still find that destroying blastocysts for stem cell research is unethical. For instance, U.S. President George Bush’s Council on Bioethics in 2001 reminds one of such positions and of Kant’s Categorical Imperative as it stated that “it is morally wrong to exploit and destroy developing human life, even for good reason” [6].

Virtue Ethics Approach

Virtue ethics is an approach that tells us what kind of people we should strive to be and how we can be such people. For example, using something known as the eudaimonia perspective can be useful for this topic. Eudaimonia can be described as achieving self-realization and happiness. People struggle to improve their character and prevent suffering on the way to eudaimonia.

Applying eudaimonia to stem cell research may go something like this:

Stem cell research offers a curative way to treat destructive diseases such as spinal cord injury, Parkinson’s, Alzheimer’s, and more.
Having these disease conditions does not match the ideal of eudaimonia, as achieving this state is not possible with the pain and burden of these diseases.
As we are trying to improve our character, we must eliminate situations that prevent eudaimonia.
If the treatment of these diseases will be improved through stem cell research, then virtue ethics may find this research ethical from the point of view of eudaimonia and achieving a virtuous state.

Conversely, some virtue ethicists find it unethical to terminate embryo life for stem cell research. The argument they support for this can be described as a duty to respect the value of human life. Based on this concept, they consider that not harming human life is a virtuous human behavior. And they believe that people should strive accordingly.

Utilitarianism Ethics Approach

The basis of utilitarianism is “the greatest happiness”. The fraction of the population suffering from diseases such as Alzheimer’s, Parkinson’s, and diabetes increases every year. It can be argued that these diseases cause pain, discomfort, suffering, and burdens for those who have the disease as well as for their families and communities. Thus, for a utilitarian approach, it may be worth sacrificing embryos to save these people’s lives and reduce the prevalence of disease through conducting further stem cell research.

In the big picture, utilitarianism focuses on the maximum benefit that all of humanity will achieve through some action. The important thing here is to save as much life as possible, and it is very important to have lives that can be saved. When we look at stem cell research from this point of view, there is no problem in using embryos. Stem cell research provides for the greatest happiness by saving lives while reducing overall suffering.

After examining the purpose of stem cell research, it can be stated that it has a morally right consequence from a utilitarian approach. Stem cell treatment contributes to saving many people’s lives, prolonging human life, reducing health care costs, and more. Since the research and treatments carried out will serve the benefit of many people, they are supported by the utilitarian perspective.


Stem cell research has been a controversial topic for some time. When this topic is analyzed by different ethical approaches, all of them reveal different ethical results, and may even be used to argue both for and against this type of research. It is important to understand the ethical implications of stem cell research to respect the benefit and fundamental humanity of all interested sides. Although stem cell research has provided improvements for the quality of life of some, these actions can still be questioned morally. In addition, stem cell research continues to be an ethical dilemma within both political and religious ideologies. For example, each country has different legal regulations on stem cell research based often on their own internal dialogue on what is right. While reaching a common understanding about when personhood begins may cause this issue to be more tractable within an ethical framework, it is likely that questions will still persist as to the moral right to conduct embryonic stem cell research.


  1. He S, Nakada D, Morrison SJ. Mechanisms of stem cell self-renewal. Annu Rev Cell Dev Biol. 2009; 25:377-406. doi:10.1146/annurev.cellbio.042308.113248
  2. Mesenchymal stem cells: the ‘other’ bone marrow stem cells. (2004). Retrieved from
  3. Mirahmadi, M., Rezanejadbardaji, H., Irfan-Maqsood, M., Mokhtari, M., Naderi-Meshkin, H. (2016). Stem Cell Therapy for Neurodegenerative Diseases: Strategies for Regeneration against Degeneration. Cell Therapy and Regenerative Medicine Journal. 1. 3. 10.15562/ctrm.11.
  4. Embryonic stem cell research: an ethical dilemma. (2008). Retrieved from
  5. The Ethics of Embryonic Stem Cell Research. (2005). Retrieved from
  6. Bernard Lo, Lindsay Parham, Ethical Issues in Stem Cell Research, Endocrine Reviews, Volume 30, Issue 3, 1 May 2009, Pages 204–213,

Büsra Elkatmis is an undergraduate student studying molecular biology and genetics at Gebze Technical University and a Research Associate in the BMSIS Young Scientist Program. She’s interested in plant science and the origin of life and enjoys growing plants in her spare time.