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Is it possible for humans to wall off a branch of knowledge that is deemed too dangerous， risky or formidable to pursue？ That is what James Burke， the science historian， asked in his 1985 documentary series， The Day the Universe Changed. In light of a powerful new technology that is revolutionizing the field of modern genetics， Burke’s challenge is fresh on the minds of scientists across the world.
In April 2015， Huang Junjiu and his team at Sun Yat-sen University in Guangzhou published the results of their experiments in which， for the first time in history， human embryos had been genetically modified. As a result of the ferocious international debate over the ethical implications that the experiments had sparked， Huang has since declined any interviews with the media.
In his work， Huang sought to modify the genes responsible for the serious blood disorder beta-thalassemia. Huang used a technology called Crispr-Cas9 on embryos unable to result in live births. Nonetheless， the results were mixed， and not viable for effective treatment at present.
Since then， scientists have in the United Kingdom applied for a license to carry out experiments on human embryos. According to January 13 Reuters article， Kathy Niakan， a stem cell scientist from London’s Francis Crick Institute， would use Crispr-Cas9 in an attempt to improve infertility treatments， stating that “the only way we can understand human biology at this early stage is by further studying human embryos directly.”
The use of Crispr-Cas9 has provided scientists with the ability to edit genes with great precision， ease， and relative cheapness—setting it apart from previous gene-editing technology that was expensive and cumbersome in comparison.
The editing of genes that can be inherited， a technique known as germline modification， could also set the stage for the move from therapeutic modifications to human enhancements. From being able to change the color of your eyes， your intelligence or height， to the extreme application of a range of improvements to build human super-soldiers or bio-weapons， Crispr-Cas9 brings the realm of science fiction a leap closer to reality. Aside from germline modification， the technology could also be used to change non-inheritable or “somatic” cells to treat disease in a single person.
By altering the human germline， the technology—derived from the DNA of bacterial immune systems—also has the potential to eradicate hereditary illnesses， as well as enhance physical and mental characteristics. Nonetheless， scientists have sounded the alarm against the premature use of Crispr-Cas9 in humans， since alterations to the embryos could be passed on to future generations. Simmering debate
In an effort to debate the potential benefits and pitfalls of the technology， more than 400 participants from 20 countries gathered in Washington， D.C.， to attend the International Summit on Human Gene Editing. The event was organized by the U.S. National Academies of Sciences and Medicine， the Royal Society in London， and the Chinese Academy of Sciences， and underscored China’s eminence in the field of genetics. Attendees were joined by Jennifer Doudna of the University of California， Berkeley， and Feng Zhang of the Broad Institute of MIT and Harvard—two of the pioneers of the technology’s potential.
In a statement released at the summit on December 3， 2015， concerns over gene editing were portrayed as including “risks of inaccurate editing （such as off-target mutations）， the difficulty of predicting harmful effects that genetic changes may have...， and the fact that， once introduced into the human population， genetic alterations would be difficult to remove and would not remain within any single community or country.”
The statement also gave the possibility that“permanent genetic ‘enhancements’ to subsets of the population could exacerbate social inequities or be used coercively，” and warned of “the moral and ethical considerations in purposefully altering human evolution using this technology.”
Doudna， who helped organize the event， claimed in an article published in the journal Nature， “Opinion on the use of human-germline engineering varies widely. Some scientists favor the rapid development of the technology， whereas others advise banning it for the foreseeable future.”
“In my view， a complete ban might prevent research that could lead to future therapies， and it is also impractical given the widespread accessibility and ease of use of Crispr-Cas9，”claimed Doudna. “Instead， solid agreement on an appropriate middle ground is desirable.”
What would constitute a middle ground for the use of this breakthrough technology？ Regardless of the still heated debate， scientists around the world have continued to plunge head-first into the uncharted and precarious waters of genetic modification.
A sprout of hope
In China， the use of Crispr-Cas9 has been a boon to geneticists， and has opened up a number of possibilities for research and experimentation that may someday affect the food we eat.
Gao Caixia is the principal investigator at the Institute of Genetics and Developmental Biology in the Beijing-based Chinese Academy of Sciences. Gao has worked on engineering herbicideresistant rice， as well as corn designed to withstand drought. In September last year， her team’s work on establishing a virus-resistant immune system in plants through the use of Crispr-Cas9 was published in Nature Plants.“The Crispr system exists in bacteria to defend themselves from viruses， but plants do not have it，” stated Gao in an interview with Beijing Review. “So we thought about what if plants had Crispr—of course plants could protect themselves from viruses. So we borrowed this system and put it in plant cells.” Such applications of the technology could have a thoroughly transformative impact on modern agriculture， and world’s food production.
“Take wheat for example—wheat always has diseases，” explained Gao enthusiastically. “If we do nothing， the yield will be decreased. So， what can we do？ Normally， we use fungicides—then we have to think about the environmental costs and the food itself which can be easily contaminated. But if we have a chance to modify a single gene， then the plant has resistance against a variety of diseases.”
Asked about the impact of Crispr-Cas9 on the future of food and human society， Gao responded that it will mainly have an impact on medicine， and may help end cancer and genetic diseases. “It also has a bright future for its use in agriculture，” she said. Gao pointed out that once the world’s population reaches a certain threshold， and as the environment deteriorates， the modification of genes through Crispr-Cas9 will offer a new hope for future food security.
In addition to Gao’s work on crops， other Chinese researchers have been using geneediting technology to pursue a variety of goals. Geneticist Huang Xingxu of the Shanghai Tech University was seeking permission to work on the genetic modification of human embryos， too， but told Beijing Review that “since it’s a very sensitive issue， we stopped the plan.” Huang’s motivation was “to test the specificity and safety of Crispr in humans’ primary cells—I believe it provides a powerful tool for the treatment of some diseases from genetic mutations.” Yet Huang was among many scientists who have voiced concerns over the possible use of geneediting technology to create “designer babies.”
Brave new genes
In his 1932 book Brave New World， author Aldous Huxley envisioned a dystopian world in which natural human reproduction had been abolished， replaced by a system composed of the artificial selection of traits desirable to its societies. Crispr-Cas9 has given humankind the means to pursue a new path of knowledge， and its destination may not be far off from what Huxley envisioned. Fran？oise Baylis， Professor and Canada Research Chair in Bioethics and Philosophy at Dalhousie University in Nova Scotia， was one of the organizers of the gene-editing summit last year. Baylis told Beijing Review of her belief—though not endorsement—that germline modification of mitochondrial and nuclear DNA will happen regardless of the debate surrounding it.
Baylis views this technology as a platform for human enhancement. She believes that“human genetic enhancements are inevitable because of capitalist forces， heedless liberalism， a desire for knowledge， a desire to outperform， and a fair amount of hubris that has us believing that ‘the future is ours for the shaping.’”
In a similar vein， James Burke claimed in his 1979 documentary series Connections， “Today， the people who make things change， the people who have that knowledge， are the scientists and the technologists， who are the true driving force of humanity.”
Humankind has developed the tools to control its progeny—is it possible to cordon off the technology， and would it even be in the best interest of the species to do so？ It is up to the concerted efforts of the global community to shape the discourse and foster debates as to whether this technology is to be used for the benefit or downfall of mankind.
In April 2015， Huang Junjiu and his team at Sun Yat-sen University in Guangzhou published the results of their experiments in which， for the first time in history， human embryos had been genetically modified. As a result of the ferocious international debate over the ethical implications that the experiments had sparked， Huang has since declined any interviews with the media.
In his work， Huang sought to modify the genes responsible for the serious blood disorder beta-thalassemia. Huang used a technology called Crispr-Cas9 on embryos unable to result in live births. Nonetheless， the results were mixed， and not viable for effective treatment at present.
Since then， scientists have in the United Kingdom applied for a license to carry out experiments on human embryos. According to January 13 Reuters article， Kathy Niakan， a stem cell scientist from London’s Francis Crick Institute， would use Crispr-Cas9 in an attempt to improve infertility treatments， stating that “the only way we can understand human biology at this early stage is by further studying human embryos directly.”
The use of Crispr-Cas9 has provided scientists with the ability to edit genes with great precision， ease， and relative cheapness—setting it apart from previous gene-editing technology that was expensive and cumbersome in comparison.
The editing of genes that can be inherited， a technique known as germline modification， could also set the stage for the move from therapeutic modifications to human enhancements. From being able to change the color of your eyes， your intelligence or height， to the extreme application of a range of improvements to build human super-soldiers or bio-weapons， Crispr-Cas9 brings the realm of science fiction a leap closer to reality. Aside from germline modification， the technology could also be used to change non-inheritable or “somatic” cells to treat disease in a single person.
By altering the human germline， the technology—derived from the DNA of bacterial immune systems—also has the potential to eradicate hereditary illnesses， as well as enhance physical and mental characteristics. Nonetheless， scientists have sounded the alarm against the premature use of Crispr-Cas9 in humans， since alterations to the embryos could be passed on to future generations. Simmering debate
In an effort to debate the potential benefits and pitfalls of the technology， more than 400 participants from 20 countries gathered in Washington， D.C.， to attend the International Summit on Human Gene Editing. The event was organized by the U.S. National Academies of Sciences and Medicine， the Royal Society in London， and the Chinese Academy of Sciences， and underscored China’s eminence in the field of genetics. Attendees were joined by Jennifer Doudna of the University of California， Berkeley， and Feng Zhang of the Broad Institute of MIT and Harvard—two of the pioneers of the technology’s potential.
In a statement released at the summit on December 3， 2015， concerns over gene editing were portrayed as including “risks of inaccurate editing （such as off-target mutations）， the difficulty of predicting harmful effects that genetic changes may have...， and the fact that， once introduced into the human population， genetic alterations would be difficult to remove and would not remain within any single community or country.”
The statement also gave the possibility that“permanent genetic ‘enhancements’ to subsets of the population could exacerbate social inequities or be used coercively，” and warned of “the moral and ethical considerations in purposefully altering human evolution using this technology.”
Doudna， who helped organize the event， claimed in an article published in the journal Nature， “Opinion on the use of human-germline engineering varies widely. Some scientists favor the rapid development of the technology， whereas others advise banning it for the foreseeable future.”
“In my view， a complete ban might prevent research that could lead to future therapies， and it is also impractical given the widespread accessibility and ease of use of Crispr-Cas9，”claimed Doudna. “Instead， solid agreement on an appropriate middle ground is desirable.”
What would constitute a middle ground for the use of this breakthrough technology？ Regardless of the still heated debate， scientists around the world have continued to plunge head-first into the uncharted and precarious waters of genetic modification.
A sprout of hope
In China， the use of Crispr-Cas9 has been a boon to geneticists， and has opened up a number of possibilities for research and experimentation that may someday affect the food we eat.
Gao Caixia is the principal investigator at the Institute of Genetics and Developmental Biology in the Beijing-based Chinese Academy of Sciences. Gao has worked on engineering herbicideresistant rice， as well as corn designed to withstand drought. In September last year， her team’s work on establishing a virus-resistant immune system in plants through the use of Crispr-Cas9 was published in Nature Plants.“The Crispr system exists in bacteria to defend themselves from viruses， but plants do not have it，” stated Gao in an interview with Beijing Review. “So we thought about what if plants had Crispr—of course plants could protect themselves from viruses. So we borrowed this system and put it in plant cells.” Such applications of the technology could have a thoroughly transformative impact on modern agriculture， and world’s food production.
“Take wheat for example—wheat always has diseases，” explained Gao enthusiastically. “If we do nothing， the yield will be decreased. So， what can we do？ Normally， we use fungicides—then we have to think about the environmental costs and the food itself which can be easily contaminated. But if we have a chance to modify a single gene， then the plant has resistance against a variety of diseases.”
Asked about the impact of Crispr-Cas9 on the future of food and human society， Gao responded that it will mainly have an impact on medicine， and may help end cancer and genetic diseases. “It also has a bright future for its use in agriculture，” she said. Gao pointed out that once the world’s population reaches a certain threshold， and as the environment deteriorates， the modification of genes through Crispr-Cas9 will offer a new hope for future food security.
In addition to Gao’s work on crops， other Chinese researchers have been using geneediting technology to pursue a variety of goals. Geneticist Huang Xingxu of the Shanghai Tech University was seeking permission to work on the genetic modification of human embryos， too， but told Beijing Review that “since it’s a very sensitive issue， we stopped the plan.” Huang’s motivation was “to test the specificity and safety of Crispr in humans’ primary cells—I believe it provides a powerful tool for the treatment of some diseases from genetic mutations.” Yet Huang was among many scientists who have voiced concerns over the possible use of geneediting technology to create “designer babies.”
Brave new genes
In his 1932 book Brave New World， author Aldous Huxley envisioned a dystopian world in which natural human reproduction had been abolished， replaced by a system composed of the artificial selection of traits desirable to its societies. Crispr-Cas9 has given humankind the means to pursue a new path of knowledge， and its destination may not be far off from what Huxley envisioned. Fran？oise Baylis， Professor and Canada Research Chair in Bioethics and Philosophy at Dalhousie University in Nova Scotia， was one of the organizers of the gene-editing summit last year. Baylis told Beijing Review of her belief—though not endorsement—that germline modification of mitochondrial and nuclear DNA will happen regardless of the debate surrounding it.
Baylis views this technology as a platform for human enhancement. She believes that“human genetic enhancements are inevitable because of capitalist forces， heedless liberalism， a desire for knowledge， a desire to outperform， and a fair amount of hubris that has us believing that ‘the future is ours for the shaping.’”
In a similar vein， James Burke claimed in his 1979 documentary series Connections， “Today， the people who make things change， the people who have that knowledge， are the scientists and the technologists， who are the true driving force of humanity.”
Humankind has developed the tools to control its progeny—is it possible to cordon off the technology， and would it even be in the best interest of the species to do so？ It is up to the concerted efforts of the global community to shape the discourse and foster debates as to whether this technology is to be used for the benefit or downfall of mankind.