What's New :
IAS Mains 2024: Complete (GS & Optional) Syllabus Revision & Updation. Get Details

Why human cells grown in monkey embryos sparked ethics debate

Published: 26th Apr, 2021

Recently, scientists and researchers at Salk Institute of Biological Studies, USA for the first time grew human cells in monkey embryos.


Recently, scientists and researchers at Salk Institute of Biological Studies, USA for the first time grew human cells in monkey embryos.


  • The study was conducted by the Scientists with an aim to study how the two types of cells develop with each other.
  • The research has a potential to progress in what has been termed as ‘chimeric research’, but it has also ignited an ethical debate on such studies.
  • Though Chimeras had been created using different techniques that involve fusing of embryos of two different animals for over 20 years now, it has never been done on humans. 


What have the researchers done?

  • The embryos were derived from Macaques and then were injected with human stem cells.
  • This mixture was then allowed to grow for 20 days before being destroyed.
  • The chimera, if implanted into a monkey uterus, could theoretically develop into a live-born animal, which will have cells from both a human and a monkey.
  • This type of life form is termed as an ‘Chimera’. Chimera is a hypothetical organism from Greek mythology, which was part lion, part goat and part snake. In this case, a part-human chimera.
  • Scientists have created, what can be called as a ‘Chimeric tool’, by integrating human cells into embryos of macaque monkeys.

Stem Cells


  • Stem cell is a premature unspecialized cell which can -
    • Split and create more stem cells
    • Develop into specialized cells like Brain cells, Muscle cells etc.


  • They are of three types:
    • Embryonic Stem Cells: These exist only during embryonic or early stages of development.
    • Adult Stem Cells: They are found in almost all tissues and organs of the body and are used to repair damaged organs.
    • Induced pluripotent stem cells or iPSC’s: They are made in laboratories and are not found naturally in the human body. They have properties similar to embryonic stem cells.

Stem Cell Therapy:

  • It is a regenerative medicine, which promotes repair of dysfunctional, diseased or damaged tissue.

 Stem Cell Therapy in India:

  • Currently, India does not have any laws or regulations with regard to Stem cell therapy.
  • “National Guidelines for Stem Cell Research” jointly formulated by the Department of Biotechnology and the Indian Council of Medical Research.
  • As per the National Guidelines for Stem Cell Research (2017), at present, there are no approved indications for stem cell therapy other than the hematopoietic stem cell transplantation (HSCT) for hematological disorders.
  • Accordingly, all stem cell therapy other than the above shall be treated as investigational and conducted only in the form of a clinical trial after obtaining necessary regulatory approvals.
  • Use of stem cells for any other purpose outside the domain of clinical trials will be considered unethical and hence is not permissible.

What’s the purpose of chimeric study?

  • It has been argued that this ability to grow cells of two different species together, can have following uses,
    • research and medicine,
    • advancing current understanding about embryonic development,
    • Understanding disease onset and progression
    • Understanding ageing
    • Drug evaluation and
    • Address the critical need for organ transplantation
  • This research can be used to build new animal models to study human diseases like Alzheimers and develop new treatments.
  • Researchers also argue that chimeric tools provide a new method which can help in studying how certain diseases originate.
    • A particular gene causing a certain type of cancer can be engineered in a human cell. This cell can then be inserted in a chimeric model. This chimeric model can be then used to study the disease progression. It will help us in understanding the disease better and obtaining better results than an animal model.

What are the Ethical Concerns regarding the study?

The study starts an ethical conundrum, on how a life- form should be treated.

  • Moral Status:
    • Moral Status is a concept which states that life forms should be treated based on interest and capabilities.
    • According to this, humans have a higher moral status than monkeys.
    • But the moral status, the rights and obligations of human-non-human Chimera is not defined.
  • Hybrid Futures:
    • It is also a possibility that human chimeras could give humans capabilities that exist in the animal kingdom, like bat’s sonar.
    • Such enhanced capabilities can make these lab-grown life-forms superior to humans in future.
  • Increasing injustice against animals:
    • Chimera research has a potential to increase injustice against animals, by using more and more animals in labs.
    • It will also justify using part-human animals as research subjects in labs.

Though the topic faces many ethical conundrums, its utility particularly in organ transplantation has been a major factor to push this research forward.

Way Forward

  • Proper regulations and global and national level: There is a need to have proper regulations for stem-cell research, so that researchers can follow a proper guideline.
  • Opinion of Public: Scientists have advised to open ethical debate regarding Chimeras for general public for their opinion.


Genetic research has opened new avenues for understanding of human beings. But on the other hand, it has been surrounded by ethical debates. Chimeric studies are of major concern as they have a potential to change how humans interact with life-forms around it. Thus, it becomes important that comprehensive guidelines are developed keeping in mind the ethical and scientific concerns.


Verifying, please be patient.

Enquire Now