Designer baby

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A designer baby is a baby that is the result of genetic screening or genetic modification. Embryos may be screened prior to implantation, or possibly gene therapy techniques could be used to create desired traits in a child.

Preimplantation genetic diagnosis[edit]

In medicine and (clinical) genetics pre-implantation genetic diagnosis (PGD or PIGD) (also known as embryo screening) is a procedure performed on embryos prior to implantation, sometimes even on oocytes prior to fertilization. PGD thus is an adjunct to assisted reproductive technology and requires in vitro fertilization (IVF) to obtain oocytes or embryos for evaluation. PGD used both medicine and science to increase reproductive choice of an embryo.

The in vitro fertilization procedure is carried out by removing one or two cells with a needle when the embryo is at the six to ten cell stage phase. It takes place at this cell stage because the risk of passing on a serious genetic disorder is extremely high then. This procedure helps to identify genetic defects in embryos and is mainly used for medical purposes.[1] During this process, the embryo is screened for any serious genetic defects. This can help select for positive traits by avoiding implanting embryos with genes that have potential serious diseases or disabilities.[2]

This is not a new technology - the first PGD babies, and thus also the first designer babies were created in 1989 and born in 1990.[3]

When used to screen for a specific genetic disease or for risk of getting a disease, its main advantage is that it avoids selective abortion as the method makes it highly likely that the baby will be free of the disease under consideration.

In some cases, the term "designer baby" refers to the proposed use of standard medical preimplantation genetic diagnosis to select for desired nonmedical traits of a child, such as sex, hair color and other cosmetic traits, athletic ability, or intelligence.[4] A 2012 article by Carolyn Abraham in The Globe and Mail stated that "Recent breakthroughs have made it possible to scan every chromosome in a single embryonic cell, to test for genes involved in hundreds of 'conditions,' some of which are clearly life-threatening while others are less dramatic and less certain". There is already a "microchip that can test a remarkable 1,500 genetic traits at once, including heart disease, seasonal affective disorder, obesity, athletic ability, hair and eye colour, height, susceptibility to alcohol and nicotine addictions, lactose intolerance and one of several genes linked to intelligence. It is still difficult to get enough DNA for such extensive testing but the chip designer thinks this technical problem will be solved soon.[5]

Regulation of Preimplantation Genetic Diagnosis[edit]

The possibilities of PGD applications can lead to potential problems when trying to make the distinction of when the procedure is needed or desired. For example, this procedure can select an embryo based on gender preferences.[1] Since changing a gender is not needed, but desired this could cause much debate. Additionally, the procedure is able to create a donor offspring, which can assist a pre-existing offspring for medical purposes. Artificially selecting traits through the use of PGD have caused the debate on whether there should be regulations of this procedure.

Currently, the United States federal law does not have any regulation of PGD. Those who are in favor of PGD believe the government should not be involved in the procedure and parents should have reproductive choice. The opposing side has argued that PGD will allow embryo selection based on trivial traits. While other critics believe that this procedure could lead to a new form of Eugenics.

In contrast to the United States, countries that have already prohibited the complete procedure of PGD, include Austria, Germany, Ireland, and Switzerland. While other countries have regulated PGD to only medical use, these countries include Belgium, France, Greece, Holland, Italy, Norway, and the United Kingdom.[1]

Genetic engineering of human gametes, zygotes, or embryos (aka germline modification)[edit]

The other use for designer babies concerns possible uses of gene therapy techniques to create desired traits of a child, such as disease resistance, sex, hair color and other cosmetic traits, athletic ability, and intelligence.[6]

Understanding of genetics for human traits[edit]

Genetics explains the process of parents passing down certain genes to their children. Genes are inherited from both biological parents, and each gene expresses a specific trait. The traits expressed by genes can be something physically seen—such as hair color, eye color, or height—or can be things such as diseases and disorders.[7]

Human genes are found within chromosomes. Humans have 23 pairs of chromosomes, 43 individual chromosomes. 23 chromosomes are inherited from the father, and 23 from the mother. Each chromosome can carry about 20,000 genes.[7]

Researchers have already connected the genes in the striped zebra fish which control the colour of the fish to genes in humans that determine skin colour.[8] Many other things could be discovered in further years especially with the new possibilities of cloning animals.

Scientists have been able to better understand the genetic traits for human through projects such as The Human Genome Project. This project was launched around 1990 and was an international research project that had an end goal of mapping and understanding every gene in the human body.[9] As a part of the Human Genome Project, we have been able to pin point specific locations for about 12,800 specific genes within different chromosomes.[7]

Germline modification[edit]

In order for germline modification to be successful, medical professionals must know how to introduce a gene into the patient's’ cell and the germline so that it will be transferred subsequent generations and still maintain the proper functionality.[10] The way in which genes are integrated into the DNA is what determines that difference between germline modification and somatic cell modification.[11] In order to be transferred to subsequent generations, these changes need to be carried out through the development of germ cells.[12] Changes in the germline result in permanent and heritable changes to the DNA.[11] While amplification of positive effects would occur, there is also the risk that amplification of possible negative effects would also occur.[12] Since the results are generational, it is more complicated to study the long-term effects and therefore it is not a simple task to figure out if the benefits of germline modification outweigh the harm.[12] Allowing families to have the ability to design their children and select for desirable traits is another major concern that germline modification presents.[12]

Germline modification can be accomplished through different techniques that focus on modification of the germinal epithelium, germ cells, or the fertilized egg.[11] One technique involves a specific sequence of cloned DNA being inserted into the fertilized egg using the microinjection technique.[11] The sequence in inserted directly into the pronucleus. The second technique uses the transfection process. Stem cells obtained from the embryo during the blastocysts stage are modified, combined with naked DNA, and the resulting cell is reinserted into the embryo that is developing.[11] The third technique focuses on carrying DNA into the embryo by using retroviruses.[11]

Feasibility of gene therapy[edit]

Main article: Gene therapy

Gene therapy is the use of DNA as a pharmaceutical agent to treat disease. Gene therapy was first conceptualized in 1972, with the authors urging caution before commencing gene therapy studies in humans.[13] The first FDA-approved gene therapy experiment in the United States occurred in 1990, on a four year old girl named, Ashanti DeSilva, she was treated for ADA-SCID.[14][15] Which is a disease that left her defenseless against infections spreading to and throughout her body. Dr. W French Anderson was a major lead on this clinical trial, he worked for the National Heart, Lung, and Blood Institute (National Institute of Health, R. 2016) Since then, over 1,700 clinical trials have been conducted using a number of techniques for gene therapy.[16]

Techniques in Gene Therapy[edit]

The techniques, which are also referred to as vectors (which is the considered delivery method for the healthy gene to the infected one). The amounts of techniques or vectors that have been used to conduct these clinical trials vary. A few of the techniques are basic processing, gene doping, and viral vectors. But the most beneficial ones up to this day and age are Naked DNA and or DNA complexes. The injection of the Naked DNA is the simplest method of the vector delivery method. This form of delivery is sometimes used as a natural compound, but the United States has been making large waves in synthetic compounds for gene delivery. The other form, which is DNA Complexes, is used when you cross a compound with a chemical mix in order to produce the desired compound. There are other studies that are currently underway that are considered a hybrid method, this when there is a combination of two or more gene therapy techniques used to instill the idea that the desired gene will stick during the delivery, transfer, and implant.

The techniques established by the field of gene therapy could potentially be used not to treat the disease, but to create "designer babies". This form of thinking about genetic make up being used for a non-health benefit, could also be considered cloning. Cloning means to make an identical copy of something, which by using the gene therapy vectors you can modify the DNA to be something or someone identical to a person, object, or an idea. This concept can be directly related to the idea of designer babies and choosing the path in an in vitro method, to create the perfect child.

Disease Control in Gene Therapy[edit]

Gene therapy can be used in both a genetic disorder path as well as an acquired disease. Some of the genetic disorders that can be tried in a clinical trial are ADA-SCID, which as stated earlier, is Severe Combined Immune Deficiency, CGD which is Chronic Granulomatous Disorder- inability to fight off bacterial and fungal infections, Hemophilia which is when the body cannot produce blood clots and this can be fatal, as well as many other genetic disorders that are being discovered. Some of the acquired diseases that can be potentially controlled in a clinical trial with gene therapy are Cancer, Neurodegenerative disease such as Parkinson’s Disorder or Huntington's Disease, as well as many other diseases that are still underway within current clinical trials.[17]

Ethics of proposed germline modification of humans[edit]

Lee Silver has projected a dystopia in which a race of superior humans look down on those without genetic enhancements, though others have counseled against accepting this vision of the future.[18] It has also been suggested that if designer babies were created through genetic engineering, that this could have deleterious effects on the human gene pool.[19] Some futurists claim that it would put the human species on a path to participant evolution.[18][20] It has also been argued that designer babies may have an important role as counter-acting an argued dysgenic trend.[21]

There are risks associated with genetic modifications to any organism. When focusing on the ethics behind this treatment, medical professionals and clinical ethicists take many factors into consideration. They look at whether or not the goal and outcome of the treatment are supposed to impact an individual and their family lineage or a group of people.[11] The main ethical issue with pure germline modification is that these types of treatments will produce a change that can be passed down to future generations and therefore any error, known or unknown, will also be passed down and will affect the offspring.[10] New diseases may be introduced accidentally.[8][22]

The use of germline modification is justified when it is used to correct genetic problems that can’t be treated with somatic cell therapy, stabilize DNA in a mating that has the potential to be high risk, provide an alternative to the abortion of embryos that genetically problematic for a family, and intensify the incidence of genes that are favorable and desirable.[11] This can ultimately lead to perfected lineages on a genotypic level and possibly a phenotypic level.

Safety is a major concern when it comes to the gene editing and mitochondrial transfer. Since the effects of germline modification can be passed down to multiple generations, experimentation of this treatment brings forth many questions and concerns about the ethics of completing this research.[11] If a patient has undergone germline modification treatment, the coming generations, one or two after the initial treatment, will be used as trials to see if the changes in the germline have been successful.[11] This extended waiting time could possess harmful implications since the effect of the treatment is not known until it has been passed down to a few generations. Problems with the gene editing may not appear until after the child with edited genes is born.[23] If the patient assumes the risk alone, consent may be given for the treatment, but it is less justified when it comes to giving consent for future generations.[11] Germline modification is considered a more ethically and morally acceptable treatment when a patient is a carrier for a harmful trait and is treated to improve the genotype and safety of the future generations.[11]

Since experimentation of the germline occurs directly on embryos, there is a major ethical deliberation on experimenting with fertilized eggs and embryos and killing the flawed ones.[11] The embryo cannot give consent and some of the treatments have long-lasting and harmful implications.[11] Germline modification would be more practical if sampling methods were less destructive and used the polar bodies rather than embryos.[11]

See also[edit]

References[edit]

  1. ^ a b c Stankovic, Bratislav (2005-02-07). "'It's a Designer Baby!' - Opinions on Regulation of Preimplantation Genetic Diagnosis". Rochester, NY: Social Science Research Network. 
  2. ^ Walker, Mark (2008-01-01). ""Designer Babies" and Harm to Supernumerary Embryos". American Philosophical Quarterly. 45 (4): 349–364. 
  3. ^ Handyside AH, Kontogianni EH, Hardy K, Winston RM (1990). "Pregnancies from biopsied human preimplantation embryos sexed by Y-specific DNA amplification". Nature. 344 (6268): 768–70. doi:10.1038/344768a0. PMID 2330030. 
  4. ^ Naik, Gautam. "A Baby Please. Blond, Freckles -- Hold the Colic". The Wall Street Journal. Retrieved 18 October 2012. 
  5. ^ Carolyn Abraham, Unnatural selection: Is evolving reproductive technology ushering in a new age of eugenics?, January 07, 2012, The Globe and Mail
  6. ^ Gordon JW (1999). "Genetic enhancement in humans". Science. 283 (5410): 2023–4. Bibcode:1999Sci...283.2023G. doi:10.1126/science.283.5410.2023. PMID 10206908. 
  7. ^ a b c "What is Genetics?". News-Medical.net. 2009-12-11. Retrieved 2016-11-15. 
  8. ^ a b Green, Ronald M. (2007). Babies By Design: The Ethics of Genetic Choice. New Haven: Yale University Press. pp. 96–97. ISBN 978-0-300-12546-7. 129954761. 
  9. ^ "An Overview of the Human Genome Project - National Human Genome Research Institute (NHGRI)". www.genome.gov. Retrieved 2016-09-27. 
  10. ^ a b Anderson, W. French (1985-08-01). "Human Gene Therapy: Scientific and Ethical Considerations". Journal of Medicine and Philosophy. 10 (3): 275–292. doi:10.1093/jmp/10.3.275. ISSN 0360-5310. PMID 3900264. 
  11. ^ a b c d e f g h i j k l m n o Lappé, Marc (1991-12-01). "Ethical Issues in Manipulating the Human Germ Line". Journal of Medicine and Philosophy. 16 (6): 621–639. doi:10.1093/jmp/16.6.621. ISSN 0360-5310. PMID 1787391. 
  12. ^ a b c d Dresser, Rebecca (2008-01-01). Gordijn, Bert; Chadwick, Ruth, eds. Medical Enhancement and Posthumanity. The International Library of Ethics, Law and Technology. Springer Netherlands. pp. 191–205. doi:10.1007/978-1-4020-8852-0_12. ISBN 9781402088513. 
  13. ^ "Gene therapy for human genetic disease?". Science. 178 (4061): 648–9. 1972. Bibcode:1972Sci...175..949F. doi:10.1126/science.178.4061.648. PMID 4343766. 
  14. ^ Sheridan, C. (2011). Gene therapy finds its niche. Nature Publishing Group, 29(2), 121–128. Nature Publishing Group. doi:10.1038/nbt.1769
  15. ^ "Gene Therapy". 
  16. ^ J. Gene Med. Gene Therapy Clinical Trials Database.
  17. ^ "Gene Therapy for Disease". 
  18. ^ a b Silver, Lee M. (1998). Remaking Eden: Cloning and Beyond in a Brave New World. Harper Perennial. ISBN 0-380-79243-5. 
  19. ^ Baird, Stephen L. (April 2007). "Designer Babies: Eugenics Repackaged or Consumer Options?" (PDF). Technology Teacher. 66 (7): 12–16. Archived from the original on March 28, 2014. 
  20. ^ Hughes, James (2004). Citizen Cyborg: Why Democratic Societies Must Respond to the Redesigned Human of the Future. Westview Press. ISBN 0-8133-4198-1. 
  21. ^ Lynn, Richard; Harvey, John (2008). "The decline of the world's IQ". Intelligence. 36 (2): 112–20. doi:10.1016/j.intell.2007.03.004. 
  22. ^ Agar, Nicholas (2006). "Designer Babies: Ethical Considerations". ActionBioscience.org. 
  23. ^ Pang, Ronald T.K (January 2016). "Designer babies". Obstetrics, gynecology and reproductive medicine. 26 (2): 59–60. doi:10.1016/j.ogrm.2015.11.011. 

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