What if these improvements were available only to the richest societies, or the richest people? Critics cite a host of fears. Children would be the subject of experiments. Parents would be influenced by genetic advertising from IVF clinics.
Germ-line engineering would encourage the spread of allegedly superior traits. And it would affect people not yet born, without their being able to agree to it. Others predict that hard-to-oppose medical uses will be identified. A couple with several genetic diseases at once might not be able to find a suitable embryo.
Treating infertility is another possibility. One cause is a genetic defect in which a region of about one million to six million DNA letters is missing from the Y chromosome. Although not all the details have been worked out, he thinks the technology could replace DNA letters essentially without side effects.
It can lead to augmentation. Another drastically cuts the risk of heart attacks. People with it never get dementia and remain sharp into old age. Church thinks CRISPR could be used to provide people with favorable versions of genes, making DNA edits that would act as vaccines against some of the most common diseases we face today.
Church tends to dodge questions about genetically modified babies. Some thinkers have concluded that we should not pass up the chance to make improvements to our species. A Pew Research survey carried out last August found that 46 percent of adults approved of genetic modification of babies to reduce the risk of serious diseases. Nick Bostrom, an Oxford philosopher best known for his book Superintelligence , which raised alarms about the risks of artificial intelligence in computers, has also looked at whether humans could use reproductive technology to improve human intellect.
What if everyone could be a little bit smarter? Or a few people could be a lot smarter? To some scientists, the explosive advance of genetics and biotech means germ-line engineering is inevitable. Of course, safety questions would be paramount. But ultimately, if the benefits seem to outweigh the risks, medicine would take the chance. But someone had to take the plunge. In January, on Saturday the 24th, around 20 scientists, ethicists, and legal experts traveled to Napa Valley, California, for a retreat among the vineyards at the Carneros Inn.
She had become aware that scientists might be thinking of crossing the germ line, and she was concerned. Now she wanted to know: could they be stopped? But that swings both ways. At the meeting, along with ethicists like Greely, was Paul Berg, a Stanford biochemist and Nobel Prize winner known for having organized the Asilomar Conference, a historic forum at which biologists reached an agreement on how to safely proceed with recombinant DNA, the newly discovered method of splicing DNA into bacteria.
Should there be an Asilomar for germ-line engineering? Doudna thinks so, but the prospects for consensus seem dim. Biotechnology research is now global, involving hundreds of thousands of people. Doudna told me she hoped that if American scientists agreed to a moratorium on human germ-line engineering, it might influence researchers elsewhere in the world to cease their work.
Doudna said she felt that a self-imposed pause should apply not only to making gene-edited babies but also to using CRISPR to alter human embryos, eggs, or sperm—as researchers at Harvard, Northeastern, and OvaScience are doing.
And I think those experiments can be done in nonhuman systems. I would favor a very cautious approach. Not everyone agrees that germ-line engineering is such a big worry, or that experiments should be padlocked. Greely notes that in the United States, there are piles of regulations to keep lab science from morphing into a genetically modified baby anytime soon.
There are thousands of mostly rare and nasty genetic diseases that can be pinpointed to a specific gene mutation. When it comes to more complex things like personality and intelligence, we know very little. Nearly anything you can measure for humans, he says, can be studied through genetics, and analysing the statistics for huge numbers of people often reveals some genetic component.
If the genetic basis of attributes like intelligence and musicality is too thinly spread and unclear to make selection practical, then tweaking by genetic manipulation certainly seems off the menu too. Greely suspects, even if it is used at first only to avoid serious genetic diseases, we need to start thinking hard about the options we might be faced with.
Others doubt that there will be any great demand for embryo selection, especially if genetic forecasts remain sketchy about the most desirable traits. All the same, societies are going to face tough choices about how to regulate an industry that offers PGD with an ever-widening scope. One of the easiest things to screen for is sex.
Gender-specific abortion is formally forbidden in most countries, although it still happens in places such as China and India where there has been a strong cultural preference for boys. But prohibiting selection by gender is another matter. How could it even be implemented and policed? By creating some kind of quota system? And what would selection against genetic disabilities do to those people who have them? Once selection beyond avoidance of genetic disease becomes an option — and it does seem likely — the ethical and legal aspects are a minefield.
When is it proper for governments to coerce people into, or prohibit them from, particular choices, such as not selecting for a disability? How can one balance individual freedoms and social consequences? But one must ground government action in a stronger set of concerns about promoting the wellbeing of all individuals while permitting the widest range of personal liberty of conscience and choice. Two technological advances are needed for this to happen, says bioethicist Henry Greely of Stanford University in California.
The production of embryos for IVF must become easier, more abundant and less unpleasant. And gene sequencing must be fast and cheap enough to reveal the traits an embryo will have. It sounds drastic, but would not be much worse than current egg-extraction and embryo-implantation methods. And it could give access to thousands of eggs for future use. An even more dramatic approach would be to grow eggs from stem cells — the cells from which all other tissue types can be derived.
Doctor Jeffrey Steinberg, founder of Fertility Institutes, says that parents can have a baby whose eye color is different from theirs, so long as they have the genetic code of different eye colors that can be transmitted to their child. Not everyone who has green eyes, for instance, has parents or even a single parent with green eyes, says Steinberg.
We are searching for the codes, hidden or otherwise that you may or may not carry that will allow you to produce a child with the eye color you seek…If the necessary building blocks or codes are present, based on the tested genetics, we allow parents the opportunity to enter the program to produce embryos destined to be tested for general genetic health euploidy , gender if desired and eye color genes. As in the case of many other human traits, eye color is not determined by a single gene but rather a complex combination of many genes.
The color of the iris can range from a very light blue to dark brown. Most of the time, eye color is described as blue, green, hazel, or brown. Brown is the most common eye color in the world. Lighter eye colors such as blue or green are found almost exclusively in people of European descent, according to the Genetics Home Reference of the National Library of Medicine. Some time ago, researchers thought that eye color was the result of a single gene, and they employed a simple hereditary model whereby parents who had blue eyes, for example, could not have a baby with brown eyes.
However, later studies demonstrated that this model was overly simplistic.
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