Some of the most promising, cutting-edge medical research falls under the broad field of genetics -- whether it's mapping the human genome or learning to identify cancer-causing genes. But over the last 70-odd years, some genetic experiments have, perhaps inevitably, attracted a fair amount of controversy. Controversy does not necessarily mean that a particular line of medical inquiry is unethical or not worthwhile -- many lawmakers and scientists, for example, favor some use of genetically modified crops -- yet there are some cases where genetic experiments clearly qualify as abhorrent. Take the Nazis' brutal medical experiments, which were inspired by Aryan-supremacist ideology and notions that certain ethnic groups possessed certain physical or mental advantages over other groups.
In this article, we'll take a look at 10 genetic experiments, all of which have faced some controversy, but some of which still represent important fields of study. We'll begin by tackling one of the most contentious, but fascinating, subjects of them all: cloning.
10. Animal Cloning
The seminal day in the history of animal clothing is, undoubtedly, July 5, 1996, when Dolly the sheep was born (although the event wasn't announced until the following year). Before Dolly, no mammal had been cloned from adult DNA. Earlier cloning efforts had used embryonic cells: By splitting two-cell embryos apart, scientists caused two genetically identical organisms to develop, a process that had been successfully performed almost a century earlier with both sea urchins and salamanders.
Since Dolly, scientists have cloned numerous other types of animals, including horses, rats, deer, cats, pigs and mice. In May 2010, a Spanish breeder of fighting bulls produced, for the first time, a cloned bull to serve as a stud. The seeming ease -- and increasing availability -- of animal cloning has raised a host of difficult questions. Should we only clone less intelligent animals? Should we clone beloved pets? Should cloned animals be allowed to reproduce and enter the food supply? Should we try to use cloning to save endangered species, to "improve" animals or to resurrect extinct species? Will cloning imperil biodiversity?
Some governments have addressed these questions via legislation -- in the U.S., the Food and Drug Administration regulates animal cloning -- but science and economics may have, to an extent, outstripped policy. As of summer 2010, meat from cloned livestock had found its way to market in several European countries, and the U.S. Department of Agriculture had outlined a framework for allowing the sale of cloned meat (from certain animals) in the U.S. [source: Kanter]. Just as we now choose between meat labeled organic or raised with hormones, we may soon be deciding whether to purchase meat accompanied by a "cloned" sticker.
9. Genetically Modified Crops
As with animal cloning, the debate over genetically modified (GM) crops often comes down to varying governmental or international regulations, as well as debates between scientists, lawmakers, farmers and agribusinesses. There are strong arguments to be made for GM crops, particularly from a humanitarian perspective. For example, in August 2010, a team of British scientists announced that they had decoded the wheat genome, allowing for a greater understanding of how to grow and manage wheat crops but also opening the door for potential customization of a wheat crop's DNA, which would allow it, for example, to thrive in environments affected by climate change [source: Satter].
In Europe, concern about the impact of GM crops, along with a raft of overlapping regulations -- from the European Union, the World Trade Organization and varying national law codes -- has allowed only a few GM foods to come to market.
The main virtue of GM food is that it can be "designed" to have certain built-in features. For example, a corn variety could produce a chemical that kills a certain fungus. However, activists and some scientists worry that GM food could produce unintended side effects, such as wiping out indigenous strains of crops or somehow proving harmful to human health. As of now, however, no scientific consensus exists stating that GM food is dangerous [source: Rosenthal].
In the United States, GM crops have found greater acceptance, but their place is still tenuous. In August 2010, a federal judge revoked approval of GM sugar beets, which had, until that point, represented 95 percent of all sugar beets in the country [source: Pollack].
8. Human Genetic Engineering
Just as with genetically modified foods, the genetic engineering of humans carries almost utopian potential. Disease and birth defects could be wiped out. We could live longer, be stronger and more intelligent. But there are also severe ethical concerns here. Would genetic improvements be limited to the wealthy? Similarly, would a discriminatory gap develop between the genetic "haves" and the "have nots"? Could there be other, unintentionally dangerous, side effects that are only seen when GM DNA is passed down to future generations?
In May 2008, a research team at Cornell University announced that it had created the first genetically modified human embryo, although the embryo was destroyed after five days [source: Templeton]. The scientists had added to the embryo a protein that glowed a fluorescent green. The announcement led to some debate about what governments should do to regulate the engineering of the human genome.
But a different form of genetic engineering had been used several years earlier, and in that case, the embryos had developed to term. In 2001, the BBC reported that scientists had altered children's germ lines -- the genes that are eventually passed on through reproduction -- by adding material from a third-party cell to a mother's ovum [source: Whitehouse]. The procedure was performed to compensate for the mother's infertility problems, but one British expert said at the time that the procedure was of dubious medical value and fraught with ethical concerns.
7. Stem Cell Research
Imagine a doctor being able to take a batch of cells and make them into anything he or she needs -- cells to repair the spinal cord of a paralyzed patient, for example. Such is the promise of stem cells, a pluripotent cell type that many researchers believe could lead to better therapies, or even cures, for Alzheimer's disease, various cancers and Parkinson's disease. (The actor Michael J. Fox, who has Parkinson's, is a prominent booster for stem-cell research.)
But many Americans have expressed discomfort at using embryonic stem cells for research, saying that fertilized embryos constitute human life. Generally these embryos are only a few days old; many of them are fertilized embryos left over from in vitro fertilization procedures and would normally be thrown away.
Since 1996, U.S. lawmakers, presidents and federal courts have been performing a careful dance around the issue of embryonic stem cell research. Varying laws and rulings have left open the door for research (usually on what are known as existing stem cell lines), while generally restricting or eliminating federal funding for said research.
However, despite the great potential of embryonic stem cells, some scientists and activists say the debate is a false one [source: Kilpatrick]. Advances in adult stem cell research may open the door to equally fruitful stem--cell-based therapies that don't come with the accompanying ethical baggage. Adult stem cells are found in a number of human tissues, and scientists have been using them as part of bone marrow transplants for decades. Other uses have followed, but the key breakthrough will be finding ways to "reprogram" them in the laboratory, causing them to grow into the type of cells needed for the therapy at hand [source: NIH].
6. Nazi Medical Experiments
Some of the controversial genetic experiments in this article have scientific merit, but surely not the Nazis' brutal, torturous experimentation on innocent prisoners. A leader in these barbaric practices was Dr. Josef Mengele, who experimented on twins at the Auschwitz-Birkenau death camp. Mengele's procedures often involved extensive, invasive examinations, following which the twins would be murdered by a lethal injection of phenol. The twins were then dissected and their organs and parts comparatively analyzed [source: Jewish Virtual Library].
Other Nazi medical experiments included subjecting captured Russian soldiers to extremely cold temperatures and inducing hypothermia, based on a eugenics-inspired belief that Russians possessed an inherent genetic resistance to cold. The Nazi high command hoped that the studies would yield information that would help their soldiers fighting on the frigid eastern front [source: Tyson].
In the years since the war, there has been periodic debate over whether any useful information could be derived from these studies, despite the horrors they entailed. In 1990, a report published by the New England Journal of Medicine concluded that the Nazi hypothermia studies had "all the ingredients of a scientific fraud" and that the data had no scientific value [source: Altman].
5. Gene Therapy and Jesse Gelsinger
Gene therapy is predicated on the radical notion that people with genetic disorders can be cured -- or, at least, their conditions improved -- by having new genes inserted into their DNA. Generally these therapies are applied to disorders for which there is no cure, or for which current treatments have been insufficient or only marginally successful. There have been some successes in the field but also a number of tragic failures. One type of gene therapy has cured patients of rare genetic disorders, but in several cases also caused them to develop leukemia [source: Kolata].
The most infamous gene-therapy trial involved an 18-year-old patient named Jesse Gelsinger, who died in 1999 less than a week after receiving treatment for OTCD, a rare metabolic disorder affecting the liver. His death shocked researchers and has become associated with the perils of this nascent field [source: Philipkoski].
But some new types of gene therapy are showing promise. One therapy involves placing needed genes into a cell -- rather than inserting proteins into a patient's DNA -- where they can still produce vital proteins that can cure or arrest a condition. In November 2009, a group of French researchers announced positive results in altering the gene therapy method that caused some patients to develop cancer; in this case, they successfully treated several children with ALD, a degenerative nerve disorder that's fatal within five years [source: Kolata].
4. Genetic Engineering in Animals
Use of animals for scientific and medical testing has long been controversial, so it's of little surprise that genetic engineering -- which often intersects with the world of genetically modified foods -- has attracted similar scrutiny. The FDA defines genetic engineering of animals as "a targeted and powerful method of introducing desirable traits into animals using recombinant DNA (rDNA) technology" [source: FDA]. That's a broad definition, reflecting the many ways in which scientists have experimented with animal DNA over the last couple of decades -- whether it's making pigs glow in the dark (scientists injected embryos with a fluorescent protein) or developing salmon that gain weight much faster than their non-modified brethren. (As of late August 2010, the FDA was considering whether to grant approval to a company called AquaBounty Technologies to sell one such salmon to consumers.)
But as with genetically modified foods, the genetic engineering of animals carries a host of potential complications, including fears of harming biodiversity, worries about effects on human health and ethical concerns over experimenting with healthy animals. When a French researcher created a glow-in-the-dark rabbit, protesters said that the experiment was both abusive and of little scientific value [source: ABC News]. Greenpeace in particular has warned of the unintended consequences of genetically modifying animals and says that their release into the wild would constitute a dangerous "genetic pollution" [source: Greenpeace]. Yet proponents say that we could genetically engineer livestock to produce less waste or to make better organ-donor candidates for humans, as some animal parts are already used in various transplant procedures.
3. Human-Animal Hybrid Research
At least two U.S. states -- Arizona and Louisiana -- have passed laws banning human-animal hybrids, and though these have provided fodder for some satirists, they are actually based in reality. Human-animal hybrids are already here. In 2004, scientists at the famed Mayo Clinic produced pigs that had human blood. The previous year, Chinese scientists bonded human cells to rabbit eggs, though the embryos were soon destroyed [source: Mott].
These sorts of combinatory specimens are called chimeras, calling to mind the mythical Greek creature composed of a lion's head, goat's body and snake's tail. However, don't expect to see centaurs -- horses with human torsos -- roaming your neighborhood anytime soon. Most human-animal hybrid research focuses on less dramatic experiments, such as adding a few human genes to a pig to produce better heart valves for transplant into humans (a procedure that's long been a standard medical practice). Still, many bioethicists, and some lawmakers, worry that we are crossing a line, tampering unnecessarily with animals or not setting adequate standards for what should and should not be done.
2. Henrietta Lacks and HeLa Cells
Henrietta Lacks died of cervical cancer in 1951, but her name has become associated with an immortal line of cells known as HeLa cells (the name derives from the first two letters of the patient's first and last names). Unbeknownst to Lacks, a doctor at Johns Hopkins University took a sample of her tumor, later offering it to researchers who saw the cells continue to multiply in culture -- up to this day. It was the first instance of a successfully established "immortal" cell line, although scientists remain baffled why the HeLa cells survived whereas others didn't [source: Skloot].
Since then, HeLa cells have been used in a number of groundbreaking medical experiments, such as the development of the polio vaccine and cloning studies. But the remarkable story of the HeLa cell line has been marred by some of the conditions surrounding it. First, Henrietta Lacks never gave permission for her cells to be given to researchers, nor were she or her family notified that they had. For decades, her family members were unaware of the role her cells were playing in medical science, nor had they benefited financially from the medical breakthroughs (and enormous revenues) associated with HeLa cells. Many of Lacks's relatives were poor and lacking in 2education; one of her sons has been homeless for decades [source: Skloot].
In February 2010, journalist Rebecca Skloot published a book, "The Immortal Life of Henrietta Lacks," which combined the various stories surrounding the HeLa cell line with extensive research into Lacks' life. The book was hailed by critics for humanizing an unintentional and forgotten heroine of science and for serving as a reminder that medical research cannot be divorced from respecting and honoring the human subjects who often make it possible [source: Garner].
1. Human Sexuality Studies
The question of whether there is a so-called "gay gene" that, when present, dictates that someone is homosexual is a popular line of inquiry for some researchers -- and a controversial one. The gay community is divided, with neuroscientist Steven Pinker describing two distinct camps: those who worry that discovery of a gay gene, or some other genetic basis for homosexuality, could lead to selective abortion; and those who justify the research on the grounds that finding homosexuality as genetically dictated would remove one justification for homophobia [source: Pinker].
There are, of course, other reasons researchers use to justify this particular area of research. For one, the search for a biological origin of homosexuality should be divorced from any questions of morality. For another, it's an imperative for scientists to study and explore the full range of human diversity, even -- or perhaps especially -- when thorny questions arise.
As Pinker and others have pointed out, though, human sexuality studies in the U.S. have often been a victim of the "Culture Wars," dating back to the time of Alfred Kinsey. Consequently, European scientists -- and the agencies and universities that fund them -- often show a greater willingness to step into the field [source: Pinker].
As of now, no general consensus exists as to the possible genetic basis of homosexuality, though various theories have been floated. In 2005, a team at the University of Illinois announced that it believed that multiple genes were linked to homosexuality [source: BBC News]. In 2008, another study found that homosexuality in men may be caused by an inherited gene that boosts fertility in women [source: Moskowitz].
For more information about controversial medical experiments and other related topics, take a look at the links on the next page.
Lots More Information
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More Great Links
- ABC News. "Glow-in-the-Dark Pigs Make Debut." Jan. 12, 2006. http://abcnews.go.com/Technology/Health/story?id=1498324
- Altman, Lawrence K. "Nazi Data on Hypothermia Unscientific." May 17, 1990. http://www.nytimes.com/1990/05/17/us/nazi-data-on-hypothermia-termed-unscientific.html
- Barr, Andy. "Arizona legislature targets 'human-animal hybrids.'" Politico. April 30, 2010. http://www.politico.com/news/stories/0410/36594.html
- BBC News. "Non-sex genes 'link to gay trait.'" Jan. 31, 2005. http://news.bbc.co.uk/2/hi/health/4215427.stm
- Food and Drug Administration. "Genetically Engineered Animals." U.S. Dept. of Health and Human Services. Aug. 26, 2010. http://www.fda.gov/animalveterinary/developmentapprovalprocess/geneticengineering/geneticallyengineeredanimals/default.htm
- Food and Drug Administration. "Fact Sheet: Genetically Engineered Animals." Jan. 16, 2009. U.S. Dept. of Health and Human Services. Oct. 28, 2009. http://www.fda.gov/AnimalVeterinary/DevelopmentApprovalProcess/GeneticEngineering/GeneticallyEngineeredAnimals/ucm113597.htm
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- Kilpatrick, Peter. "The Ethics of Stem Cell Research." NY Times. Aug. 24, 2010. http://www.nytimes.com/2010/08/26/opinion/l26stem.html
- Kluger, Jeffrey. "A Brief History of: Cloning." TIME. Nov. 26, 2008. http://www.time.com/time/magazine/article/0,9171,1862459,00.html
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- Moskowitz, Clara. "Why Gays Don't Go Extinct." Live Science. June 17, 2008. http://www.livescience.com/health/080617-hereditary-homosexuality.html
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- National Institutes of Health. "What are adult stem cells?" Aug. 5, 2010. http://stemcells.nih.gov/info/basics/basics4.asp
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- Oak Ridge National Laboratory. "Cloning Fact Sheet." Human Genome Project Information. http://www.ornl.gov/sci/techresources/Human_Genome/elsi/cloning.shtml
- Oak Ridge National Laboratory. "Gene Therapy." Human Genome Project Information. June 11, 2009. http://www.ornl.gov/sci/techresources/Human_Genome/medicine/genetherapy.shtml
- Philipkoski, Kristen. "Another Chance for Gene Therapy?" Wired. Oct. 1, 2009. http://www.wired.com/science/discoveries/news/1999/10/31613
- Pollack, Andrew. "Judge Revokes Approval of Modified Sugar Beets." New York Times. Aug. 13, 2010. http://www.nytimes.com/2010/08/14/business/14sugar.html
- Popular Science. "Five Reasons Why Henrietta Lacks Is the Most Important Woman in Medical History." Feb. 5, 2010. http://www.popsci.com/science/article/2010-01/five-reasons-henrietta-lacks-most-important-woman-medical-history
- Satter, Raphael G. "Scientists: we've cracked wheat's genetic code." Associated Press. Seattle Times. Aug. 27, 2010. http://seattletimes.nwsource.com/html/businesstechnology/2012736484_apeucrackingwheatscode.html?syndication=
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- Zielinski, Sarah. "Henrietta Lacks' 'Immortal' Cells." Smithsonian Magazine. Jan. 22, 2010. http://www.smithsonianmag.com/science-nature/Henrietta-Lacks-Immortal-Cells.html