Hybridizing with extinct species: George Church
art 1: Primary Post (Read the information and watch the video in Part 1 and answer the questions in Part 2)
Watch this video first and then write up your discussion
Hybridizing with extinct species: George Church at TEDxDeExtinctionLinks to an external site.
https://www.youtube.com/watch?v=oTH_fmQo3Ok
Hybridizing with extinct species: George Church at TEDxDeExtinction
Scenario: Cloning
Cloning can have multiple meanings and conjures up images of Sci-Fi movies where humans are cloned relatively quickly in the laboratory and appear as adults with the same abilities, memories, etc. as the person whose cell(s) were used to provide the genetic information. Of course, in reality, clones would start as a single cell and would have to go through the same stages of embryonic development and growth to adulthood that you did.
Useful Links:
Cloning fact sheet from ORNL
https://web.ornl.gov/sci/techresources/Human_Genome/map.shtmlLinks to an external site.
https://www.discovermagazine.com/planet-earth/5-reasons-to-bring-back-extinct-animals-and-5-reasons-not-toLinks to an external site.
http://www.independent.co.uk/news/science/the-big-question-could-cloning-be-the-answer-to-saving-endangered-species-from-extinction-1543657.html (Links to an external site.)
Part 2: Your Discussion - Secondary Post
Discuss and explore the scientific, moral, and ethical aspects of whole animal cloning. You will take on the role of consultants who has been hired to “sell” the idea of a park called ‘Preservation Land’ to rich investors. At this park, endangered and extinct animals will be cloned and put on display and used to restock wild populations.
1. General Introduction: Start off the meeting with the investors by explaining the steps involved with using somatic cell nuclear transfer (SCNT) for whole animal cloning. You may want to use Dolly the sheep as a successful example.
2. Can cloning help to save endangered species?: At the end of your introductory presentation, one of investors asks whether this has been done yet with endangered animals and if there are any potential drawbacks to using this process for preserving or restocking endangered animals. Below, relate what you would tell the investors about successful attempts to clone endangered animals, as well as the pros and cons of the use of cloning to help reverse species loss.
3. Cloning of extinct animals: One of the potential investors says that she had heard that wooly mammoths could be brought back from extinction. Below, document the basic steps it takes to theoretically clone an extinct animal that you would make the potential investors aware of. Also, note the problems that have emerged with the cloning of endangered and extinct animals, especially when forced to use surrogate mothers of a different species.
4. Human cloning: After your presentation, one very interested investor takes you aside and asks if this could be done with humans. He has a terminally ill child and wants to clone this child. Note the ethical issues associated with cloning humans that you would inform the potential investor about and how you would explain to the investor the similarities and differences that would exist between the clone and the child he has now. Do these cloned animals cause changes to humans if we happened to eat them, like cloning cows?
- Introduction: Somatic Cell Nuclear Transfer (SCNT) for Whole Animal Cloning
- Nucleus Extraction:We take a somatic cell (e.g., skin cell) from the desired animal, containing its genetic information.
- Egg Cell Preparation:We remove the nucleus from an unfertilized egg cell of a closely related species.
- Nuclear Transfer:The nucleus from the somatic cell is carefully inserted into the enucleated egg cell.
- Electrical Stimulation:The combined cell is stimulated to begin cell division and development.
- Embryo Implantation:The resulting embryo is implanted in a surrogate mother of the same species, who carries it to term.
- Can Cloning Help Endangered Species?
- Gaur, a wild ox:In 2001, scientists successfully cloned a gaur using SCNT and a surrogate mother cow.
- Pyrenean ibex, a wild goat:In 2009, an ibex was born via SCNT, though it sadly died shortly after birth.
- Technical challenges:The success rate of SCNT remains low, leading to high costs and ethical concerns about animal welfare during failed attempts.
- Genetic diversity:Cloning doesn't address the root causes of endangerment, like habitat loss and human activity. Introducing clones with limited genetic diversity into existing populations might even be detrimental.
- Reintroduction challenges:Cloned animals, raised in captivity, might lack the necessary skills and instincts to survive in the wild. Reintroduction efforts require careful planning and habitat improvement.
- Cloning Extinct Animals: The Case of Woolly Mammoths
- Ancient DNA retrieval:Scientists would need to extract well-preserved DNA from frozen mammoth remains.
- Nuclear transfer:This DNA could be inserted into the enucleated egg cells of a close relative, like an Asian elephant.
- Gestation:However, ethical considerations arise regarding using another species as a surrogate mother.
- Incomplete DNA:Mammoth DNA might be fragmented and require complex reconstruction.
- Surrogate mother health:Introducing an extinct species' embryo into a different species could pose health risks to the surrogate.
- Ethical Issues and Human Cloning
- Playing God:Cloning humans raises serious questions about playing God and manipulating human life.
- Psychological impact:The psychological impact on both the "clone" and the original individual is unpredictable and potentially harmful.
- Unintended consequences:The long-term consequences of human cloning are unknown and potentially detrimental.