What is Cloning?
"Cloning" is a very general term--it has been done by researchers for over 120 years, and there is more than just one type. In fact, cloning can mean any of the following things:
Henrietta Lacks's cells were the first human cells to be cloned; this was done using the method described in the third bullet point above.
Besides general curiosity, cloning can be used in a number of ways. It can reproduce desirable traits in an organism, can be used to study and preserve endangered species, and can be used to harvest stem cells. The last point is one of significant debate; below, and article describes conflicting opinions on this topic.
- Separating a developing embryo into two different embryos, resulting in two organisms
- Somatic cell cloning, or transferring a complete nucleus into an nucleus-free egg, and letting the embryo develop in a surrogate
- Separating a group of cells into various colonies, and letting those colonies grow
Henrietta Lacks's cells were the first human cells to be cloned; this was done using the method described in the third bullet point above.
Besides general curiosity, cloning can be used in a number of ways. It can reproduce desirable traits in an organism, can be used to study and preserve endangered species, and can be used to harvest stem cells. The last point is one of significant debate; below, and article describes conflicting opinions on this topic.
Recently, researchers have pioneered new methods for extracting and using stem cells--in this case, by cloning. Scientists took samples of somatic skin cells from 35 and 75 year old adult males, and used the somatic cell cloning technique to make a stem cell-producing embryo (not allowed to grow into a fetus). Many scientists, like Young Gie Chung from CHA University in Seoul, believe that this could pave the way for revolutionary new techniques in transplants and other similar emergency surgeries.
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Final Opinions: In this case, the potential benefits of cloning far outweigh the possible negative effects. It is important to remember that the hypothetical "fetus" in this situation would, realistically, never be viable, and the stem cells in this case would save the lives of many people in need of transplants.
Cloning, of course, is one of the things that gives Henrietta Lacks's cells their fame. They were the first human cells to be cloned (through the separate colony method described above), and many different types of HeLa cell lines resulted. Though "cloning" has been a valid process since the 1890s, the cloning of human cells marked a huge change in biotechnology; now, it could be applied to human cells (or, more specifically, Henrietta's).
"Scientists wanted to grow cellular clones--lines of cells descended from individual cells--so they could harness those unique traits. With HeLa, a group of scientists in Colorado succeeded, and soon the world of science had not only HeLa but also its hundreds, then thousands, of clones."--Rebecca Skloot (Skloot, 100).
Prenatal Genetics Testing
Prenatal genetics testing is something that many pregnant women undergo--it can help detect many genetic and chromosomal disorders, such as Down's Syndrome (three copies of the 21 chromosome), Klinefelter Sydrome (two x chromosomes and one y chromosome), and Turner Syndrome (only one x chromosome).
This article from the New York Times summarizes two basic methods for prenatal genetic testing--amniocentesis and chorionic villus sampling. In these two procedures, small cell samples are taken from fluid in the uterus or the placenta (respectively), and are tested for any glaring chromosomal disorders. This article also talks about potential applications of these procedures--mothers can choose to simply assuage their fears with these tests, or they may choose to terminate their pregnancies.
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Final Opinions: While many pro-life advocates worry at the possibility of terminated pregnancies, prenatal genetics testing can help to broaden women's informed consent for their pregnancies. In fact, banning prenatal genetic testing on the grounds of pro-life ideals would be an ethical issue in itself; to do so would be to deliberately lessen women's education and choice surrounding their pregnancies.
So, how would this have helped Henrietta? We know that she was planning to have more children at the time of her death, and that she and her husband, Day, were first cousins. Since this would have increased the risk of chromosomal and genetic disorders, Henrietta might have used prenatal genetic testing to learn about possible chromosomal or genetic disorders in her children.
So, how would this have helped Henrietta? We know that she was planning to have more children at the time of her death, and that she and her husband, Day, were first cousins. Since this would have increased the risk of chromosomal and genetic disorders, Henrietta might have used prenatal genetic testing to learn about possible chromosomal or genetic disorders in her children.