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Parahuman



 

A parahuman is a human-animal hybrid. Scientists have also done extensive research into the combination of genes from different species, e.g. adding human (and other animal) genes to bacteria and farm animals to mass-produce insulin and spider silk proteins. Note that individual genes can be transplanted between species without the transplantation of whole cells.

Contents

Human-animal hybrids

Parahumans are also referred to as "human-animal hybrids." The term "parahuman" is not used in scientific publications. The term is sometimes used to sensationalize research that involves mixing biological materials from humans and other species. It was used in a National Geographic article to describe an experiment in 2003, during which Chinese scientists at the Shanghai Second Medical University successfully fused human cells with rabbit eggs.[1]

Rationale

There are several possible reasons that parahumans or chimeras might be created. The current forms of chimera exist for medical and industrial purposes, e.g. production of drugs and of organs suitable for organ transplantation. Other experiments aim to reveal knowledge about the function of the human body, e.g. by creating mice with a human-like immune system to study AIDS or with a brain incorporating human nerve cells. Restrictions on cloning and stem cell research makes chimera research a more attractive alternative in some researchers' eyes.

If parahumans are created using germline engineering, they breed true, and are different enough from ordinary humans to be unable to breed with them, this would qualify them as being a distinct species. Parahumans created using only somatic genetic engineering would have "normal" children. Another key difference is that a germ-line parahuman would most likely be modified before birth, while a somatic parahuman could be an adult human who chose to be modified. The latter is sometimes seen as more ethical because the changes are made with informed consent; a counterargument is that no harm is done to a person born with modified genes because the person had no control over their genetics in the first place.

Human-animal hybrids for scientific research

Scientists in Britain have been granted permission to create human-animal hybrid embryos by injecting human DNA into cows' eggs for stem cell research.[2][3][4][5] Researchers from Newcastle University and King's College London submitted the application to the Human Fertilization and Embryology Authority (HFEA), an independent regulatory body that oversees embryo research and fertility treatment in Britain. The scientists said the hybrid human-bovine embryos could prove useful in pursuing treatments to prevent Parkinson's disease and Alzheimer's, as well as spinal cord injuries, diabetes and arthritis. Instead of using human eggs, the researchers will remove the nuclei from cows' eggs and replace them with cells from the patients to create cloned stem cell lines that contain the same genetic mutation that results in these neurological disorders.

"We feel that the development of disease-specific human embryonic stem cell lines from individuals suffering from genetic forms of neurodegenerative disorders will stimulate both basic research and the development of new treatments for devastating brain diseases," Dr. Stephen Minger, of the stem cell biology laboratory at King's College London, said in a release.

Minger cited the short supply of human eggs left over from in vitro fertilization, which have been used for stem cell research but have to be acquired through surgery on the women. "The hybrid embryo would be 99.9 percent human. The only bovine element would be found in DNA outside the nucleus of the cell."

The proposal has appalled critics of stem cell research, who slam the idea of creating so-called "chimera" (see: Chimera (genetics)) embryos as an unethical and potentially dangerous practice.

Ethics

There is no scientific field of "parahuman research". Ethical, moral, and legal issues of "parahuman research" are speculative extensions of existing issues that arise in actual research. Some individuals, particularly those with deep religious ideals, see the creation of chimeras to devalue the uniqueness of human life or to be tampering with a divine plan.

In contrast, some transhumanists see this technology as one of many ways to overcome fundamental human limitations, such as disease and aging, and point out the many potential commercial and medical benefits. [6] The debate can also be seen in terms of individual freedom to use germinal choice technology or reprogenetics.

Other ethical issues (shared with genetic engineering in general) involve the legal and moral status of a hybrid individual or race, whether the decision-making power over its creation should lie with governments or individuals, whether a distinction should be drawn between strictly medical treatments (restoring lost function) and those enhancing humans above some "normal" standard, whether medical ethics allow doctors to offer parahuman-related treatments, and whether xenotransplantation poses risks of cross-species disease transfer.

Parahumans in fiction

Science fiction authors sometimes use the term "parahuman" to refer to distinct "races" of human-like creatures created through genetic engineering. A parahuman created starting from a nonhuman animal template could be considered a biological uplift, as in the works of David Brin, while a parahuman based more closely on the human form and genome might also be called posthuman or transhuman. The role-playing game Transhuman Space and the related book "GURPS Bio-Tech" use the term "parahuman" interchangeably with "variant human" to refer to a wide array of heavily-modified "racial templates." These range from a "Gilgamesh-Series" resembling normal humans but with increased lifespan; a "Lepus-Series" resembling anthropomorphic rabbits; and a "Tek Rat" described as a mix of human, raccoon, and possum. The television series Dark Angel featured a group of parahumans (referred to in the series as "transgenics") with animal DNA selected to enhance their abilities to serve as supersoldiers.

Parahumans are a useful concept for the science fiction writer because they offer ways to explore issues such as racism, alienation, religion, and freedom, and to justify colonization of exotic environments such as the ocean or planets with non-Earthlike properties.

One famous work involving parahumans (though not referred to as such) is The Island of Doctor Moreau by H.G. Wells. During the "Golden Age" of Science Fiction Cordwainer Smith's parahuman "underpeople" (humans derived from animal stock) were an important part of his Instrumentality stories. More recently, Caitlín R. Kiernan, who has described herself as a parahumanist, has explored the subject of parahumans in a number of sf stories, including The Dry Salvages, "Riding the White Bull," and "Faces in Revolving Souls". John Crowley, in his novel Beasts, centered his plot around lion-human hybrids, with a lone fox-human hybrid acting as a kingmaker.

Humor authors such as Lewis Carroll in English and Sukumar Ray in Bangla have had parahuman characters in their writings. More recently Teenage Mutant Ninja Turtles and Full Metal Alchemist are themed around human-animal hybrids.

See also

References

  1. ^ Mott, Maryann (January 25 2005). Animal-Human Hybrids Spark Controversy. National Geographic News. Retrieved on 2006-03-22.
  2. ^ British regulators say yes to human-animal (hybrid) embryo research - CBC News, Canada, September 5, 2007
  3. ^ British scientists plan to create human-cow embryos - CBC News, Canada, November 8, 2006
  4. ^ Ministers bow to hybrid pressure - Ministers have bowed to pressure to allow the creation of human-animal hybrid embryos for research. – BBC News, 17 May 2007, UK
  5. ^ Mott, Maryann (January 25 2005). Animal-Human Hybrids Spark Controversy. National Geographic News. Retrieved on 2006-03-22.
  6. ^ Position on Human Germline Genetic Modification (December 24 2005). Retrieved on 2006-12-14.
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Parahuman". A list of authors is available in Wikipedia.
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