RedskinRat
02-02-2014, 11:51 PM
Hurry it up!
Are We Too Close to Making Gattaca a Reality? - Scientific American (http://blogs.scientificamerican.com/brainwaves/2013/10/28/are-we-too-close-to-making-gattaca-a-reality/)
Preventing and treating diseases are not the only reasons people have turned to pre-implantation genetic diagnosis. PGD also makes it possible for parents to predetermine characteristics of a child to suit their personal preferences. In a few cases, people have used PGD to guarantee that a child will have what many others would consider a disability, such as dwarfism or deafness. In the early 2000s, lesbian couple Sharon Duchesneau and Candy McCullough—both deaf from birth—visited one sperm bank after another searching for a donor who was also congenitally deaf. All the banks declined their request or said they did not take sperm from deaf men, but the couple got what they were looking for from a family friend. Their son, Gauvin McCullough, was born in November 2001; he is mostly deaf but has some hearing in one ear. Deafness, the couple argued, is not a medical condition or defect—it is an identity, a culture. Many doctors and ethicists disagreed, berating Duchesneau and McCullough for deliberately depriving a child of one of his primary senses.
And:
Since Steinberg’s contentious proposal in 2009, researchers have developed a much clearer understanding of the various genes responsible for the pigments in our bodies. Forensic geneticist Manfred Kayser of Erasmus MC and his colleagues have published many studies in which they have accurately identified people’s eye and hair color by looking at their DNA. Their tests cannot recognize every possible shade, but they are specific enough to distinguish between brown, blue and mottled brown-blue eyes, as well as brown, black, blonde and red hair. Such studies are intended to help solve crimes, but clinicians at fertility clinics could easily adapt the strategies for PGD. Based on ongoing research, Manfred thinks he and other scientists will soon be able to confidently identify skin color by looking at someone’s genes as well. In the more distant future, he adds, researchers will probably learn enough to deduce the texture of a person’s hair, the shape of his or her face, and the person’s height.
Today, genetic analysis can also reveal the likelihood of various quirks of human biology that some people find fascinating and others might consider trivial. Take, for example, the probability that someone will experience “Asian glow.” The ALDH2 gene codes for an enzyme named aldehyde dehydrogenase that converts a toxic byproduct of alcohol metabolism into a benign acid. People with only one or no working copies of the gene feel nauseated and flush red when they drink alcohol. Around 50 percent of East Asians have underactive aldehyde dehydrogenases. Earwax consistency is also relatively easy to predict with a genetic test because it is controlled by a single gene: one version of the gene produces sticky amber ear wax; the other makes dry, gray, flaky earwax. A single gene also largely determines one’s ability to taste certain bitter compounds commonly found in Brussels sprouts, coffee, cabbage and other foods.
These examples of relatively straightforward relationships between genes and traits are exceptions to the daunting complexity of human genetics. Most characteristics of the human body—even seemingly simple ones like earlobe attachment, dimples and hair whorls—have stumped researchers with far more convoluted genetics than they anticipated. That’s why confidently reporting eye and hair color based on DNA is a relatively recent accomplishment. In high school, you may have learned that eye color is a simple Mendelian trait in which one or two dominant copies of a gene produces brown eyes whereas two recessive versions result in blue eyes. In fact, more than a dozen genes likely interact to determine the hue of your iris. So, when it comes to something as multi-faceted as intelligence or personality, we may never have a particularly useful predictive genetic test. For the foreseeable future, then, any possibility of designer babies may be limited to rather basic—though, to many parents, important—human features: essentially, the shape and color of a child’s face and body.
And finally:
“Unfettered development of PGD applications is providing parents and fertility specialists an increasing and unprecedented level of control over the genetic make-up of their children,” wrote Tania Simoncelli, Assistant Director for Forensic Sciences within the White House Office of Science and Technology Policy, in 2003. “Indeed, if ever there was a case for a ‘slippery slope,’ this is it. Advances in PGD, together with cloning and genetic engineering, are tending towards a new era of eugenics. Unlike the state-sponsored eugenics of the Nazi era, this new eugenics is an individual, market-based eugenics, where children are increasingly regarded as made-to order consumer products.”
Are We Too Close to Making Gattaca a Reality? - Scientific American (http://blogs.scientificamerican.com/brainwaves/2013/10/28/are-we-too-close-to-making-gattaca-a-reality/)
Preventing and treating diseases are not the only reasons people have turned to pre-implantation genetic diagnosis. PGD also makes it possible for parents to predetermine characteristics of a child to suit their personal preferences. In a few cases, people have used PGD to guarantee that a child will have what many others would consider a disability, such as dwarfism or deafness. In the early 2000s, lesbian couple Sharon Duchesneau and Candy McCullough—both deaf from birth—visited one sperm bank after another searching for a donor who was also congenitally deaf. All the banks declined their request or said they did not take sperm from deaf men, but the couple got what they were looking for from a family friend. Their son, Gauvin McCullough, was born in November 2001; he is mostly deaf but has some hearing in one ear. Deafness, the couple argued, is not a medical condition or defect—it is an identity, a culture. Many doctors and ethicists disagreed, berating Duchesneau and McCullough for deliberately depriving a child of one of his primary senses.
And:
Since Steinberg’s contentious proposal in 2009, researchers have developed a much clearer understanding of the various genes responsible for the pigments in our bodies. Forensic geneticist Manfred Kayser of Erasmus MC and his colleagues have published many studies in which they have accurately identified people’s eye and hair color by looking at their DNA. Their tests cannot recognize every possible shade, but they are specific enough to distinguish between brown, blue and mottled brown-blue eyes, as well as brown, black, blonde and red hair. Such studies are intended to help solve crimes, but clinicians at fertility clinics could easily adapt the strategies for PGD. Based on ongoing research, Manfred thinks he and other scientists will soon be able to confidently identify skin color by looking at someone’s genes as well. In the more distant future, he adds, researchers will probably learn enough to deduce the texture of a person’s hair, the shape of his or her face, and the person’s height.
Today, genetic analysis can also reveal the likelihood of various quirks of human biology that some people find fascinating and others might consider trivial. Take, for example, the probability that someone will experience “Asian glow.” The ALDH2 gene codes for an enzyme named aldehyde dehydrogenase that converts a toxic byproduct of alcohol metabolism into a benign acid. People with only one or no working copies of the gene feel nauseated and flush red when they drink alcohol. Around 50 percent of East Asians have underactive aldehyde dehydrogenases. Earwax consistency is also relatively easy to predict with a genetic test because it is controlled by a single gene: one version of the gene produces sticky amber ear wax; the other makes dry, gray, flaky earwax. A single gene also largely determines one’s ability to taste certain bitter compounds commonly found in Brussels sprouts, coffee, cabbage and other foods.
These examples of relatively straightforward relationships between genes and traits are exceptions to the daunting complexity of human genetics. Most characteristics of the human body—even seemingly simple ones like earlobe attachment, dimples and hair whorls—have stumped researchers with far more convoluted genetics than they anticipated. That’s why confidently reporting eye and hair color based on DNA is a relatively recent accomplishment. In high school, you may have learned that eye color is a simple Mendelian trait in which one or two dominant copies of a gene produces brown eyes whereas two recessive versions result in blue eyes. In fact, more than a dozen genes likely interact to determine the hue of your iris. So, when it comes to something as multi-faceted as intelligence or personality, we may never have a particularly useful predictive genetic test. For the foreseeable future, then, any possibility of designer babies may be limited to rather basic—though, to many parents, important—human features: essentially, the shape and color of a child’s face and body.
And finally:
“Unfettered development of PGD applications is providing parents and fertility specialists an increasing and unprecedented level of control over the genetic make-up of their children,” wrote Tania Simoncelli, Assistant Director for Forensic Sciences within the White House Office of Science and Technology Policy, in 2003. “Indeed, if ever there was a case for a ‘slippery slope,’ this is it. Advances in PGD, together with cloning and genetic engineering, are tending towards a new era of eugenics. Unlike the state-sponsored eugenics of the Nazi era, this new eugenics is an individual, market-based eugenics, where children are increasingly regarded as made-to order consumer products.”