Designer baby is a term that refers to the product of a genetically engineered baby. These babies are "designed" (fixed/changed) while still in the womb to achieve more desired looks, skills, or talents.
Preimplantation genetic diagnosis
In medicine and (clinical) genetics pre-implantation genetic diagnosis (PGD or PIGD) (also known as embryo screening) refers to procedures that are 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.
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. 
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. As of 2009, selecting for the sex of a child was already feasible since it requires only identifying an X or Y chromosome, but selecting for nonmedical traits was not due to the amount of genetic material required, and one example has been described where a deaf couple used to PGD to select for a deaf baby. 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.
Genetic engineering of human gametes, zygotes, or embryos (aka germline modification)
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, or intelligence.
Understanding of genetics for human traits
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Researchers have already connected the genes in the striped zebra fish which control the color of the fish to genes in humans that determine skin color.
Feasibility of 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. The first FDA-approved gene therapy experiment in the United States occurred in 1990, when Ashanti DeSilva was treated for ADA-SCID. Since then, over 1,700 clinical trials have been conducted using a number of techniques for gene therapy.
The techniques established by the field of gene therapy could potentially be used not to treat the disease, but to create "designer babies".
Ethics of proposed germline modification of humans
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. 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. Some futurists claim that it would put the human species on a path to participant evolution. It has also been argued that designer babies may have an important role as counter-acting an argued dysgenic trend.
- Human enhancement
- Human genetic engineering
- Eugenics in the United States
- Genetically modified organism
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- Hughes, James (2004). Citizen Cyborg: Why Democratic Societies Must Respond to the Redesigned Human of the Future. Westview Press. ISBN 0-8133-4198-1.[page needed]
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