Gene Knockdown

When the mRNA has been targeted, a double-stranded RNA (dsRNA) interferes with the disrupted micro RNA which stops it from creating a new protein (3). This method does not completely block protein production but there are still residual amounts of protein produced, however in Daisy the cow, the protein for BLG was no longer detected in her milk. Daisy the cow was cloned by a technique called the somatic cell nuclear transfer (SCNT). This means that a somatic cell, or body cell, was taken from the original parent, in this case an ear skin cell from a high-merit cow named Aspen (4), and cultured in a low nutrient state. It then becomes dormant, where the nutrients are keeping the cell alive but it no longer undergoes cell replication. The nucleus of the dormant cell is now removed and is inserted into an enucleated oocyte (egg) cell, which is the reproductive cell of a donor cow. Enucleated means that the nucleus of this reproductive cell has been removed in order for the new one to be infused in it. The dormant somatic cell and the reproductive cell are then shocked with an electrical pulse which sends a surge of energy which allows them to fuse into one

Reproductive cloning is similar to IVF because it also brings embryo into existence. This potential infertility treatment involves the creation of embryo using the genetic material of the parent. This is done by extracting nucleus from the person’s somatic cell and transfer into an oocyte through somatic cell nuclear transfer. Thus, the processed oocyte

that goes into creating a clone. First, scientist remove a somatic cell from an animal that they

Somatic Cell Nuclear Transfer is the process of creating a cell, organ, or organism by using an egg cell from one donor and a body cell from another donor. It is used in therapeutic cloning, which is the creation of a healthy body cell to replace a faulty cell, allowing for patient-specific treatments. SCNT can also be used in reproductive cloning, which is used to clone full animals or possibly humans. The process of SCNT is completed by taking an egg cell from a female donor, and a body cell, any body cell, from another donor. The nucleus is removed from the egg cell, while the nucleus from the body cell is implanted into the egg cell as a replacement. The cell begins to divide, and eventually grows into a developed organism with the same

Cloning, or somatic cell nuclear transfer, involves complex maneuvering. A cell is first taken from the body of the person or animal to be cloned. It is then inserted into an egg cell whose nucleus has been removed, thus creating the equivalent to a zygote, or fertilized egg. After certain chemical adjustments, the cells of the zygote divide and multiply, as if it had been created from an egg and sperm. The zygote becomes a blastocyst, an early-stage, five-day-old embryo consisting of about 150 stem cells. If the blastocyst is placed into a surrogate mother’s uterus, it could possibly develop into a fully grown person, a replica of the original cell’s donor.

As for reproductive cloning the entire genetic code is reproduced from a single body cell of an adult individual. The most common technique is somatic cell nuclear transfer (SCNT). Scientist first take the somatic cell from the test subject they plan to clone, extract the cell’s nucleus, which includes the cell’s DNA and throw away the rest. Then they remove the nucleus of an egg cell and replace it with the somatic cell. After that step is complete they reconstruct the egg with a blast of electricity to simulate cell division. If the process is done correctly the cell then divides normally and forms a blastocyst, therefore, scientist will transfer it into a foster mother for her to flourish a new animal.

There are a variety of methods to produce a clone. One common laboratory technique in the present is somatic cell nuclear transfer (SCNT) which will be focus in the essay. In this process, the nucleus, which contains the genetic material is removed from the female donor egg cell (ovum) and discarded, leaving the enucleated egg cell. Next, the nucleus of somatic cell from another donor is removed but kept; the enucleated somatic cell is discarded. Then, the nucleus of the somatic cell is fused with the enucleated egg cell by applying electric current. The egg cell containing the somatic cell nucleus will begin to divide. After the single cell forms a blastocyst, it is implanted into a surrogate mother uterus for further development.

The two implications for gene knockdown I will be discussing are the Survival of population and the health or survival of individual. The survival of the population is affected if the calves die or becomes unhealthy without the BLG protein present in the cow’s milk. This will have a major effect on the survival of the cattle population. This is because if the majority of the calves being born are unable to survive without the BLG protein this means that rest of the calves cannot survive as well, as they are all genetically identical. Hence the population number will decrease significantly.

SCNT has a proven negative and positive health effect on cloned animals- not yet shown on Daisy- through telomeric differences. Telomeric differences is when the DNA sequence at both ends of the chromosome shrink in length as DNA replicates itself. It is the natural part of aging but in cloned individuals some have extra short chromosomes resulting in aging faster and therefore dying earlier than the expected lifespan. In other animals the lifespan was extended. According to “learn genetics” a chromosome from a cloned cow had longer telomeres and therefore potentially a longer lifespan though this has yet to be determined in Daisy due to other factors and she is currently only 11 or so months old.

The nucleus containing the donor cells will produce an embryo with the exact same genetic information as the donor cow. In Further detail, the nucleus which contains the organisms DNA of a somatic cell (a body cell other than sperm or an egg cell) is removed and the rest of the cell is seemingly discarded. At the same time the nucleus of an egg cell is removed. Afterwards the nucleus of the somatic cell is then inserted into the egg cell. After being inserted into the egg cell, the somatic cell nucleus is reprogrammed by the host cell. The egg now containing the nucleus of a somatic cell, is stimulated with a shock called mild electric pulse and will begin to divide. After many mitotic divisions, this single cell forms a blastocyst (an early stage embryo with about 100 cells) with almost identical DNA to the original organism. To make Daisy, researchers isolated a somatic cell from an adult female cow. Next they would have removed the nucleus and all of its DNA from an egg cell. Then

“Clones are organisms that are exact genetic copies. Every single bit of their DNA is identical” (Cloning). Clones can range anywhere from clones of whole organisms to clones of cells. “There are two ways to make an exact genetic copy of an organism in a lab: artificial embryo twinning and somatic cell nuclear transfer” (Cloning). Artificial embryo twinning is the “low-tech” way to create clones (Cloning). Artificial embryo twinning mimics the process in nature that creates identical twins (Cloning). In nature, twins in the first days after the egg and sperm join (Cloning). The embryo at this point is still made of a small number of unspecialized cells (Cloning). Identical twins are genetically identical because they are developed from the same fertilized egg after the embryo splits in half (Cloning). “Artificial embryo twinning uses the same approach, but it is carried out in a Petri dish instead of inside

There are a few ways in which cloning can be achieved, one of which is somatic cell nuclear transfer, SCNT. SCNT has become the most practical way of reproductive cloning. Although the success of somatic cell nuclear transfer is very low, 0.1% - 0.5%, the few successes in cloning have been with the use of SCNT. Somatic cell nuclear transfer is a technique that transfers the nucleus of a cell into the cytoplasm of another cell which has no nucleus. Once inside the egg, the nucleus is reprogrammed by egg cytoplasmic factors to become zygote nucleus, a fertilized egg. Since the nucleus holds all the DNA, or the directions for life, the cell will proceed to grow into the organism of which the nucleus came from. Scientists needs more than just a method of cloning to bring back an extinct species. They need an intact DNA strand, and the longer a species has been

Have you ever wondered what it would be like to have a second you? The process of cloning is something that is not necessarily very new but is something that is constantly being researched and improved. Most commonly in cloning the somatic cell nuclear transfer method is used.This is when you take a somatic cell(any cell other than the sex cells) from the person being cloned and a donor egg cell and extract the nucleus from the donor egg cell replacing it with the nucleus from the somatic cell. This fuses the donor egg and somatic cell together and next is placed in a surrogate organism that gives birth to that cell that was created. That is the process of cloning an organism. The world of cloning is new and mysterious but is something that could very

The cell grows into a normal egg and the egg grows into a normal baby that is then born (Tamang). The third way a clone can be created is the “Honolulu Technique.” It is the most recent and most effective technique. Donor nuclei are enucleated and inserted into egg cells. There is no vitro (fertilization of an egg in a laboratory dish or test tube) like nuclear transfer. The egg cells are placed in a chemical culture to jumpstart the cell’s growth, just like fertilization in nature. The cells develop into embryos which will be transplanted into a surrogate mother and born like a normal baby ("Three Ways…”).

Cows produce a protein in their milk called BLG and many infants are allergic to this protein. Two to three hundred infants are allergic to cow’s milk, and BLG allergies are seemingly a large part of this. Various organizations are trying to investigate ways to manipulate the genetic material in the modified dairy cattle with the main goal of producing milk that doesn’t contain the lethal BLG protein. Daisy is a genetically modified cloned cow and whom does not produce milk containing the BLG protein but does however have the gene for it. But the mRNA for the BLG protein has become nonfunctional. Once the protein has been manipulated the cow containing the modified gene is cloned to produce a calf with the same genetic material. This cloned cow will then not produce the protein. This technique is very useful to produce a herd without the protein to gather more milk. Because of this protein produced (BLG) this causes a lot of people and infants to become very sick and ill. Therefore by creating a herd of cows using the processes of Gene Knockdown and Cloning this would not only cut out the lethal protein of BLG, but this will also create cows that don’t possess the BLG protein and therefore creating healthy milk for all to drink.