Animal Cloning Research

Basic Research - Stem cellSourcesStem cell Stem cells are unspecialized cells. Therefore, Stem cells can differentiate by having various potentials. Stem cells are the only cell that has a natural ability to produce new cell types and becomes specialized. This property of stem cells serves as a repair system of the body. Daughter cells are formed by the division of stem cells and become specialized cells with a specific function. ex) blood cells, neuron, heart muscle cells, and skin cells Sources of stem cells

1. Embryonic stem cells: Obtained from early-stage embryo

2. Cord blood stem cells: Obtained from umbilical cord and placenta after a baby is born

3. Adult stem cells: Obtained from fully developed tissues (ex. brain, skin, and bone marrow)

Why are stem cells needed? Stem cells are useful for stem cell transplant as therapeutic use. Leukaemia and Osteopetrosis are examples of a disease that can be cured with therapy using stem cells. Leukaemia is Osteopetrosis is Stem cells are necessary as the body cannot produce blood and the components needed for the immune system's functioning. The new healthy stem cells develop and create every different part of blood that both the body and the immune system require. Not only for humans, but also animals use stem cell treatment. A disease that can be found in organ systems, respiratory systems, renal systems, and others in animals can be treated by stem cells. Pros and Cons with each sources of stem cells Embryonic stem cellsCord blood stem cellsAdult stem cellsPros- Unlimited growth potential - Can differentiate into any type of cells - Less chance of genetic disease- Easily obtained and stored - Commercial collection and storage are available - No rejection problems- Less chance of tumor development - No rejection problem - Does not kill the adultCons- Risk of becoming tumor cells - Removal from the embryo can destroy the embryo - Likely to be genetically different from an adult patient who is receiving the stem cell- Limited quantities from one baby’s cord - Limited capacity to divide - The umbilical cord is discarded- Difficult to obtain - Less growth potential - Limited capacity to develop

• https://www.mayoclinic.org/tests-procedures/bone-marrow-transplant/in-depth/stem-cells/art-20048117

• https://medlineplus.gov/stemcells.html

• https://www.dana-farber.org/health-library/articles/why-are-stem-cell-transplants-performed-/

• https://www.unmc.edu/stemcells/educational-resources/prosandcons.html

• https://theguyerinstitute.com/2020/10/06/how-effective-is-stem-cell-therapy/

Basic Research - cloningSourcesClone

• Offspring that is produced by a single parent

• a living organism, for instance, a plant or an animal, that has genetic information in common with another organism

• three different types of cloning:

1. gene cloning: the process of making duplicates of genes or DNA segments.

2. reproductive cloning, the process of making duplicates of entire creatures

3. therapeutic cloning, the process of making embryonic stem cells

Why are scientists doing it?

• some animals have been cloned to contain gene mutations that support scientists in studying animal diseases

• can research how diseases progress

• in order to study and understand the genes better

• to mass-produce organisms with desired qualities

Animals that have been cloned by scientists Cattle, swine, sheep, and goats have all been successfully cloned by scientists. Mice, rats, rabbits, cats, mules, horses, and one dog have also been cloned. It is not possible to clone chickens or other poultry. Somatic Cell Nuclear Transfer (SCNT)

• a scientific technique that involves transferring the nucleus of a somatic cell to the cytoplasm of an enucleated egg, which is an egg that has had its own nucleus removed in order to create a clone

1. transfer DNA from a somatic cell of an animal to an egg cell which has had its nucleus and DNA removed

2. the egg grows into an embryo with the same genes as the cell donor

3. The embryo is then implanted into the uterus of an adult female to develop

example of somatic cell nuclear transfer case: Dolly experiment

• SCNT's main practical application is in reproductive cloning of agricultural animals with extraordinary traits (for example, the capacity to produce enormous amounts of milk).

Animal reproductive cloning

• achieved by implanting a blastocyst produced from SCNT into the uterus of a surrogate mother, where the embryo grows into a fetus that is brought to term

• a method used to produce a clone or an identical copy of an entire multicellular organism

• clones are superior breeding animals used to produce healthier offsprings

Causes of low success rate on cloning experiments

• embryonic death

• failure during the implantation process

• development of a defective placenta

• https://bio.libretexts.org/Bookshelves/Microbiology/Book%3A_Microbiology_(Boundless)/7%3A_Microbial_Genetics/7.12%3A_Tools_of_Genetic_Engineering/7.12D%3A_Reproductive_Cloning

• https://www.nationalgeographic.org/encyclopedia/cloning/#:~:text=To%20make%20a%20clone%2C%20scientists,adult%20female's%20uterus%20to%20grow.

• https://www.bio.org/sites/default/files/legacy/bioorg/docs/files/Cloning_onepager.pdf

• https://hms.harvard.edu/news/improving-cloning-efficiency

• https://medlineplus.gov/cloning.html

• https://www.ed.ac.uk/roslin/about/dolly/facts/cloning

• https://learn.genetics.utah.edu/content/cloning/whyclone

• https://www.britannica.com/video/189165/change-video-DNA-nucleotide-sequence-amino-acid#:~:text=A%20mutation%20is%20a%20change,mutation%20is%20a%20point%20mutation

• https://www.genome.gov/genetics-glossary/Somatic-Cells

• https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/in-depth/placenta/art-20044425#:~:text=The%20placenta%20is%20an%20organ,umbilical%20cord%20arises%20from%20it.

• https://archive.bio.org/articles/value-therapeutic-cloning-patients#:~:text=Therapeutic%20cloning%20could%20allow%20an,lab%20into%20the%20doctor's%20office

• https://www.britannica.com/science/somatic-cell-nuclear-transfer

Basic Research - Statistic & DataSourcesRates of success and failure of somatic cell nuclear transfer in sheep Figure1: Percentage of successful Dolly experiment 1/277 = 0.361% A survey on agree and disagree about stem cell research The value of the total global stem cell therapy market in 2018 and 2029 The total global stem cell therapy market was valued at around $755 million in 2018 and it will reach around $11 billion by 2029. The success rate of stem cell treatment It has achieved positive results in over 45% of patients for one trial.

• https://www.researchgate.net/figure/Ethical-issues-around-stem-cell-research_fig13_241248923

• https://www.statista.com/statistics/1095690/stem-cell-therapy-market-worldwide-by-treatment-type/

Basic Research - Advantages and Disadvantages of Stem Cell Treatment and Animal CloningProsSourcesConsSourcesPreserve endangered animal species (environment)https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3092149/#:~:text=Stem%20cells%20are%20most%20commonly,to%20preserve%20endangered%20animal%20speciesDecrease in gene diversity (environmental)https://www.centerforfoodsafety.org/issues/302/animal-cloning/biodiversity Stem cells are usually used as a therapeutic application for the treatment of musculoskeletal injuries in dogs and horses in clinical veterinary medicine. This can prevent disease-induced extinctions. Moreover, new technology is being developed that uses stem cells to conserve endangered animals.A university researcher warned that “if there is no genetic diversity, decrease can affect all the animals simultaneously,”. When a herd has naturally occurring genetic variances, certain animals will have an inherent resistance to particular illnesses, but when clones are genetically identical, the diversity that diversity gives is gone. Cloning's commercialization would make it difficult, if not impossible, to remove flaws or negative effects that have been bred into an animal population or species.Great benefits to consumers and patients (social/economic)https://www.fda.gov/animal-veterinary/animal-cloning/primer-cloning-and-its-use-livestock-operations High cost for cloning an animal (economic)https://forbes.com/2001/06/29/0629clone.html#:~:text=Some%20scientists%20believe%20clones%20would,our%20estimates%3A%20about%20%241.7%20millionSince adult and cord blood stem cells are limited, they are very expensive. If the number of stem cells increases by animal cloning, the cost would get lower.Cloning a dog costs more than $50,000 and the estimated cost for cloning a human is $1.7 million. As such, since the cost of cloning an animal is very expensive, the research and development of this technology may be limited, and it may not be used well.Production of healthier animals from superior breeding animals that is useful for stem cell production (environmental)https://www.bio.org/sites/default/files/legacy/bioorg/docs/files/Cloning_onepager.pdf Cloned animals suffering from health problems (ethical)https://www.genome.gov/about-genomics/fact-sheets/Cloning-Fact-Sheet#:~:text=Reproductive%20cloning%20is%20a%20very,total%20of%20277%20cloned%20embryosIt is possible to produce healthier stem cells through superior breeding animals, which increases the chances of obtaining healthier stem cells. They can be used therapeutically.Most cloned animal embryos cannot develop into healthy individuals because reproductive cloning technology is inefficient. Dolly, for example, was the only alive clone out of a total of 277 cloned embryos. The chances of obtaining adult stem cells are very low because the cloned animals are less likely to become healthy adults.Stem cells from cloned animals have identical DNA with the recipient. https://www.practicalethics.ox.ac.uk/cloning-and-stem-cell https://www.scientificamerican.com/article/body-rejects-transplant-human-embryonic-stem-cells/ Stem cell rejection after transplantation is high. By cloning the patient’s DNA, it is possible to reduce tissue rejection by creating stem cells with the same DNA as the patient.