Sunday, August 9, 2015
Greece: here we go again.
Greece is on the brink of default again. It is time for another payment (to the ECB or IMF - doesn't matter) and Greece can not pay unless it gets another loan. And the troika tries to use that leverage to wean Greece away from Socialism. Do you see the irony in this? A democratic Socialist entity (Europe) trying to moderate a leftist party (Syriza) toward some fiscal responsibility. It's a losing cause.
Saturday, August 8, 2015
Trump keeps on trucking.
The saying is that when your enemies praise you, it is imperative that you review what you are doing wrong. The Liberal Media has heaped praise on FOX over their conduct of the first GOP "debate." It was not a debate, but an ambush political interview much practiced by the likes of ABS, CBS, CNN or MSNBS. The clear objective of the "moderators" was to take Trump out. CNN even thought that it was Kasich who won the debate with his "sensitive" comments about increasing spending on Medicaid and participating in a same sex wedding, or now that the Supreme Court spoke (i.e. Justice Kennedy made the deciding vote for gay 'marriage') it was settled law that should not be challenged. Since when did the Left accept defeat when things did not go their way? Why should we?
FOX "Moderators" clearly had their orders and Megyn Kelly obliged with the ambush question to Trump. It was like Cathy Crowley lying to defend Obama or Stephanopoulos trying to create the "issue" of the GOP attacking contraception. Megyn Kelly was a stand in for Hillary Clinton charging the GOP with anti woman bias.
This was a black day for what is left of impartial journalism. That FOX would stoop to such lows bodes ill for the concept of a free election.
Despite all this, Trump prevailed. That is to say, his support has not deserted him. The reason is not because he is the best candidate, but because he champions the issues the people care about. Which are: 1. the refusal of the political class to defend the Country and 2. the moral decay fostered by the Ruling Class.
FOX "Moderators" clearly had their orders and Megyn Kelly obliged with the ambush question to Trump. It was like Cathy Crowley lying to defend Obama or Stephanopoulos trying to create the "issue" of the GOP attacking contraception. Megyn Kelly was a stand in for Hillary Clinton charging the GOP with anti woman bias.
This was a black day for what is left of impartial journalism. That FOX would stoop to such lows bodes ill for the concept of a free election.
Despite all this, Trump prevailed. That is to say, his support has not deserted him. The reason is not because he is the best candidate, but because he champions the issues the people care about. Which are: 1. the refusal of the political class to defend the Country and 2. the moral decay fostered by the Ruling Class.
Friday, August 7, 2015
FOX: debates one and two.
This was a much awaited (i.e. much hyped) "debate." How do you hold a debate with 10 participants? You can not. So, FOX opted for a confrontational assault on the candidates to see who could deflect it the most. And, FOX could not do a fair distribution of air time either. Ted Cruz and Ben Carson were virtually shut out; notwithstanding that Cruz is the only debater with debate credentials. Liberal outlets are elated. They didn't think that FOX had it in them.
On the other hand, FOX did the candidates a favor. It was a good preparation for a hostile Media. In the debate of the seven Fiorina was the standout.
On the other hand, FOX did the candidates a favor. It was a good preparation for a hostile Media. In the debate of the seven Fiorina was the standout.
Wednesday, August 5, 2015
Check if you are a Liberal.
Victor Volsky
As a great fan of Jeff Foxworthy, it occurred to me that it might be a good idea to use his hilarious you-might-be-a-redneck comedy routine in an attempt to characterize the liberal mindset (tweaking Jeff's formula a bit to convert it from the suppositional to the unconditional). So, with apologies to the wonderful country comedian, here are some of the notable features of the liberal's mental landscape: If you believe that freedom of expression is sacrosanct but would like nothing better than to deny it to anyone who doesn't share your views, you are a liberal. If you believe that the 1st Amendment separates church from state, but not state from church, you are a liberal. If you believe that the 2nd Amendment was the founding fathers' big mistake and that the 10th Amendment shouldn't be taken seriously, you are a liberal. If you believe that endlessly discussing a problem amounts to actually solving it, you are a liberal. If you believe that the results of progressive programs are irrelevant and that only good intentions count, you are a liberal. If you believe that Mark Foley, who wrote salacious e-mails to a young but legally adult congressional page, was an evil libertine, while Gerry Studds, who had sex with an underage congressional page, was a knight in shining armor, you are a liberal intellectual. If you believe that Obama is an intellectual giant whose IQ is off the charts even though you have no idea what his IQ actually is, you are a liberal. If you believe that a decades-old drunk-driving episode in George W. Bush's biography comes under the "people's right to know" doctrine while the entire past of Barack Obama is protected by his right to privacy, you are a liberal. If you believe that we can spend and borrow our way out of the recession in keeping with the thoroughly discredited Keynesian model, you are a liberal. If you believe that taxpayers don't change their behavior when the government tries to squeeze more tax money out of them, you are a liberal. If you believe that Americans are undertaxed, while carefully hiding your own money in offshore tax shelters, you are a liberal. If you believe, with Nancy Pelosi and Valerie Jarrett, that unemployment benefits are a boon to the economy (but without taking this brilliant insight to its logical conclusion: that the path to unprecedented prosperity lies through 100% unemployment), you are a liberal. If you believe that affirmative action improves the lot of poor minorities rather than miring them in perpetual misery and dependence, you are a liberal. If you believe that Lyndon Johnson's War on Poverty failed because not enough money (a trifling $16 trillion) was spent on it, you are a liberal. If you believe that God's middle name is Kennedy, you are a liberal. If you believe that Jimmy Carter, who has been working indefatigably over the last three decades to subvert his country's foreign policy, is the best ex-president ever, you are a liberal. If you believe that the Fox News Channel is the modern-day equivalent of Völkischer Beobachter and The New York Times a light unto the world, and whatever the Times publishes is God-given truth while whatever it deems unfit to print doesn't deserve to be known, you are a liberal. If you angrily castigate your compatriots for being profligate with their energy consumption while generously allowing yourself to use more than 20 times as much energy as a regular household (see Gore, Al), you are a liberal. If you believe that your choice of a car affects the planet's climate while sunspot activity doesn't, you are a liberal. If you are notoriously stingy with personal charitable giving but deliriously generous with other people's money while proudly posing as the true benefactor of the poor, you are a liberal. If you believe that human nature is infinitely malleable and that nurture easily trumps nature, you are a liberal. If you believe that your women's studies degree is superior to a Ph.D. in engineering, you are a liberal. If you believe that the anarchists, hoodlums, and hobos who make up the Occupy movement are noble idealists who truly represent the 99 percent of America while the Tea Partiers are Nazi troglodytes and of course racists, you are a liberal. If you believe that perjury is not a crime if it is about sex, you are a liberal. If you believe that Bill Clinton defended the Constitution as he repeatedly perjured himself, you are a liberal. If you believe that Hillary's rather primitive bribery scheme with cattle futures was so complicated as to be beyond human comprehension and thus ought to be shoved into the memory hole, you are a liberal. If you believe that Chuck Colson, who served seven months behind bars for procuring a single FBI file, got away with murder, but the Clintons, who demanded from the FBI some 900 files, were defenseless lambs relentlessly persecuted by cruel Republicans, you are a liberal. If you believe that the mountains of corpses and rivers of blood that have been the chief result of all communist "experiments" are merely collateral damage, a possibly regrettable but unavoidable byproduct of the high-minded attempts to build paradise on earth and thus nothing to talk about, you are a liberal. If you believe that Alger Hiss or Julius and Ethel Rosenberg were innocent victims of McCarthyism, you are a liberal. If, to reinforce your salon cred, you bedeck your infant in a T-shirt bearing the likeness of that murderous sadist, Che Guevara, you are a liberal. If you believe, against plentiful historical evidence to the contrary, that appeasement works and that America's unilateral disarmament will surely mollify enemies by demonstrating our peaceful intentions and shame them into following our example, you are a liberal. If you believe that negotiations are the be-all and end-all of international relations and that as long as our adversaries deign to talk to us, everything is fine and dandy, even if they clearly use the negotiations as a smokescreen to pursue their nefarious schemes unmolested, you are a liberal. If you believe that the Palestinians sincerely want an accommodation with Israel and that only the stiff-necked Jews' obduracy stands in the way of Middle East peaceful settlement, you are a liberal. If you believe that all cultures are equal but that Western culture is less equal than the others, you are a liberal. If you believe that a crucifix immersed in the "artist's" urine or a bucket of paint splashed onto a canvas is genuine art, you are a liberal. If you believe that a murderous hoodlum is not really guilty because he grew up in a tough neighborhood and that "judgmentalism" is really the only crime deserving of opprobrium, you are a liberal. If you reflexively sympathize with the criminal while scornfully ignoring the crime victim, you are a liberal. If you believe that Bill Maher is indeed politically incorrect and Warren Buffet is dying to pay more taxes, you are a liberal. If you love the "people" but despise the "populace," you are a liberal. If you believe that you and your ilk will be able to fool the American people indefinitely...well, you may have a point there. | |
Tuesday, August 4, 2015
Puerto Rico defaults.
It happened this Saturday. Puerto Rico failed to make a $58M payment. PR's govt argued that missing payment should not be considered default. Unfortunately for them, that IS the definition of default. The US Congress has no plans to bail them out. Like Greece, PR had spent beyond its income.
Monday, August 3, 2015
Rewriting genetic sequences
Discussion by experts on what it is.
https://www.youtube.com/watch?v=p-t5VrCtY1Q
How the CRISPer system works.
https://www.youtube.com/watch?v=SuAxDVBt7kQ
Examples of its use.
https://www.youtube.com/watch?v=FYNkbW3lMYo
My comments.
1. This is a very useful technology when used by sane people for sane purposes.
2. Will this be used as a biological weapon? You betcha.
3. Is this how evolution took place? There was NO MACROEVOLUTION. This mechanism can introduce new mutations and even steal genes from other organisms, but not MAKE genes that are not present in organisms living already. Going from organism to organism involves different mechanisms that simply can not evolve by random mutations. All these experiments prove that an intelligent entity can change the design.
https://www.youtube.com/watch?v=p-t5VrCtY1Q
How the CRISPer system works.
https://www.youtube.com/watch?v=SuAxDVBt7kQ
Examples of its use.
https://www.youtube.com/watch?v=FYNkbW3lMYo
My comments.
1. This is a very useful technology when used by sane people for sane purposes.
2. Will this be used as a biological weapon? You betcha.
3. Is this how evolution took place? There was NO MACROEVOLUTION. This mechanism can introduce new mutations and even steal genes from other organisms, but not MAKE genes that are not present in organisms living already. Going from organism to organism involves different mechanisms that simply can not evolve by random mutations. All these experiments prove that an intelligent entity can change the design.
Gene drives. The implications.
Gene Drives" And CRISPR Could Revolutionize Ecosystem Management
A note from the authors: With this guest blog post we want to share the key features of an innovative method for the high-precision genome editing of wild populations that has been outlined by our team at the Wyss Institute, Harvard Medical School, and the Harvard School of Public Health. Our technical description of the proposed method was published today in eLife, while an accompanying essay on regulation and governance was published today in Science. We aim to introduce the technology – well in advance of any concrete implementation – in order to start a public conversation on how we might collectively explore ways to responsibly develop and use it for the betterment of humanity and the environment.
Genome engineering technologies have revolutionized genetics, biotechnology, and medical research. We may soon be able to alter not just domesticated species, but entire wild populations and ecosystems. Why, when and how might we use these novel methods to reshape our environment?
The story begins with a new technology that has made the precise editing of genes in many different organisms much easier than ever before. The so-called “CRISPR” system naturally protects bacteria from viruses by storing fragments of viral DNA sequence and cutting any sequences that exactly match the fragment. By changing the fragments and delivering the altered system into other organisms, we can cut any given gene. If we also supply a DNA sequence that the cell can use to repair the damage, it will incorporate this new DNA, precisely editing the genome. When performed in the cells that give rise to eggs or sperm, these changes will be inherited by future generations. Because most altered traits don't improve and may even decrease the organism's ability to survive and reproduce, they generally can't spread through wild populations.
Gene drives
Genes can sometimes gain a fitness advantage that doesn't rely on the organism. Most genes in sexually reproducing species have a 50% chance of being inherited by each offspring. But many genes in nature have evolved ways to beat the odds: by being passed on more than half of the time, they gain an evolutionary advantage. This can allow an inheritance-biasing “gene drive” that is initially present in a single individual to spread over many generations until it is present in all members of a population.
One type of gene drive influences inheritance by copying itself onto chromosomes that previously lacked it. When an organism inherits such a gene drive from only one parent, it makes a cut in the chromosome from the other parent, forcing the cell to copy the inheritance-biasing gene drive—and any adjacent genes—when it repairs the damage (see the figure and additional details below).
Now imagine we want to edit a particular gene—say, one controlling the immune response of mosquitoes to malaria. We could make a mosquito with an edited version of this gene and insert the CRISPR system right next to it along with a fragment directing CRISPR to cut the original—but not the edited—gene. When our altered mosquito mates with a wild mosquito, the offspring will inherit one edited and one normal copy. CRISPR will then cut the normal copy and the cell will attempt to repair the cut by copying the edited version and the CRISPR system. The offspring will now have two copies of the edited version plus CRISPR.
This insect will mate with other insects in which the same process of turning the normal genes into edited genes will be repeated. Given enough generations, CRISPR will spread the edited gene through the entire population of mosquitoes—and this is key—even if the edited gene reduces the odds that each mosquito will reproduce.
Since CRISPR can be directed to cut essentially any gene at a precisely determined location and works in every organism we've tested, CRISPR gene drives may allow us to spread nearly any type of genome alteration through many sexually reproducing populations. We describe this possibility in detail in a paper published today in the journal eLife.
Because CRISPR itself is so precise, we can envision a number of safeguards. Alterations can be reversed by releasing a new drive with an updated version of the change. It's effectively a slow-motion “undo” button for genome alterations and could work on any type of change. Similarly, only populations that have the sequence targeted by CRISPR can be altered by a drive, potentially allowing us to target subpopulations with unique sequences. This also means that deliberately altering the sequences needed by another drive can provide protection against it, allowing us to immunize populations against specific drives and their associated changes.
Limitations
There are fundamental limits to what gene drives can do. First, they cannot under any circumstances affect species that reproduce exclusively asexually, because there is no inheritance to bias. Viruses and bacteria are not susceptible, while many plants, fungi, and some animals will be resistant because they frequently reproduce without sex.
Second, gene drives can make only temporary changes. We can use them to spread traits that we consider desirable even if they are deleterious to each organism, but natural selection will eventually undo our best efforts if we give it long enough.
Third and most importantly, gene drives require many generations to spread. We could alter entire populations of fast-reproducing insects in a couple of years—depending on how many we release—but it would take decades or centuries for long-lived organisms. That's why gene drives won't be able to affect human populations without taking centuries. They're also easily detected by genome sequencing and can't spread accidentally through populations in which mate choice is artificially controlled, which greatly limits their potential to affect crops and domesticated species.
Implications
The ability to manage ecosystems by altering wild populations will have profound implications for our relationship to nature. Selective breeding and genome engineering have in many ways defined agriculture, human living and medicine, but have had comparatively little impact on most ecosystems due to the inability of domesticated crops and animals to survive in the wild. With CRISPR gene drives, we may be able to directly alter the traits or influence the population size of many non-domesticated species, which constitute the vast majority of key players in ecosystems worldwide. Given the importance of ecosystem integrity and vitality to human flourishing and the balance of life on our planet, the availability of these techniques will come with tremendous responsibility. The decision of when and where to apply this technology, and for what purposes, will be in our collective hands.
Potential Applications
Why and how might we use gene drives to intervene in a particular ecosystem? Our earlier example is perhaps the most compelling: we might use gene drives to control malaria by altering Anopheles mosquitoes that transmit the disease. Anti-malarial medicines and insecticides are losing effectiveness due to evolving resistance, while a vaccine remains out of reach despite intense research and investment. Gene drives, in contrast, might spread genes conferring malaria resistance through the mosquito populations with few if any effects on other species. Alternatively, they might be able to reduce or even eliminate the mosquitoes for long enough to permanently eradicate the malaria parasite. Similar strategies could work for other organisms that spread disease.
Gene drives might directly benefit biodiversity by controlling populations of environmentally damaging invasive species such as rats, cane toads, or lionfish. Unlike most of our current chemical or biocontrol methods, they would be specific to the target species and might be able to fully eradicate invasive populations. They might also promote more sustainable agriculture by controlling insect pests and reversing herbicide resistance in weeds, thereby supporting no-till farming.
Evaluation
Ecological changes caused by gene drives will be overwhelmingly due to the particular alteration and species, not by the CRISPR drive components. That means it doesn't really make sense to ask whether we should use gene drives. Rather, we'll need to ask whether it's a good idea to consider driving this particular change through this particular population. While gene drives could tremendously benefit humans and the environment if used responsibly, the potentially accessible nature of the technology raises concerns about the risks of accidental effects or even intentional mismanagement. In a new paper published in Science, we specifically address the regulation and risk governance of gene drive applications to promote responsible use.
The recent ecological concept in ethics may provide a framework for analysis and decision-making that can accommodate for a broad spectrum of moral values and worldviews.
Conclusion
The ability to alter populations and ecosystems using gene drives is around the corner—but not yet here today. As scientists and bioethicists, we have a professional obligation to inform society of the potential consequences of our work as early as possible. We judged the eventual development of RNA-guided gene drives to be inevitable due to the landmark theoretical work by Austin Burt, who first described the possible uses of endonuclease gene drives more than a decade ago, and the rapid advancement of CRISPR-based genome editing. After extensive discussions with experts in many fields, we elected to publish our findings in order to provide time for informed public discussion, regulatory review, and the establishment of guidelines for the safe development of the technology.
Because we are all affected by the state of our ecosystems, public oversight of technologies capable of ecological management will be essential. We recommend that all future research involving gene drives and other technologies capable of altering populations and ecosystems be conducted in full public view, with all empirical data and predictive models freely and openly shared with the global community in a transparent and understandable format. Only through broadly inclusive and well-informed public discussions can we as a society decide how best to manage our shared environment. We hope that many of you will join.
George Church is a member of Scientific American's Board of Advisors
-----------------------------
How Endonuclease Gene Drives Work
Standard drives spread introduced genes or specific patterns of genome changes through populations. They might be used to drive a gene that interferes with the spread of a disease, such as an anti-malarial peptide, or to disrupt a natural gene important for disease spread.
Suppression drives reduce the number of organisms in a target population. Naturally occurring suppression drives are always found together with a resistance element that allows the species to survive. It is believed that the emergence of drives in the past may have driven species all the way to extinction when resistance did not develop in time. There are many different ways to build a suppression drive, some of which have quite different effects. They could be used to control the populations of environmentally destructive invasive species such as mosquitoes, rats, cane toads, or lionfish that currently threaten many ecosystems. They might even be able to render pest populations uniquely vulnerable to molecules that don't affect other organisms.
Reversal drives undo earlier genome changes caused by natural evolution, human-inserted transgenes, earlier gene drives, or even naturally evolved mutations such as those conferring pesticide or herbicide resistance in pests and weeds.
Immunization drives immunize existing populations to prevent them from being affected by other gene drives.
Precision drives can only spread alterations through populations of organisms that have a unique DNA sequence.
5
Invasive cane toads might one day be controlled with CRISPR gene drives. Photo Credit: U.S. Geological Survey
A note from the authors: With this guest blog post we want to share the key features of an innovative method for the high-precision genome editing of wild populations that has been outlined by our team at the Wyss Institute, Harvard Medical School, and the Harvard School of Public Health. Our technical description of the proposed method was published today in eLife, while an accompanying essay on regulation and governance was published today in Science. We aim to introduce the technology – well in advance of any concrete implementation – in order to start a public conversation on how we might collectively explore ways to responsibly develop and use it for the betterment of humanity and the environment.
Genome engineering technologies have revolutionized genetics, biotechnology, and medical research. We may soon be able to alter not just domesticated species, but entire wild populations and ecosystems. Why, when and how might we use these novel methods to reshape our environment?
The story begins with a new technology that has made the precise editing of genes in many different organisms much easier than ever before. The so-called “CRISPR” system naturally protects bacteria from viruses by storing fragments of viral DNA sequence and cutting any sequences that exactly match the fragment. By changing the fragments and delivering the altered system into other organisms, we can cut any given gene. If we also supply a DNA sequence that the cell can use to repair the damage, it will incorporate this new DNA, precisely editing the genome. When performed in the cells that give rise to eggs or sperm, these changes will be inherited by future generations. Because most altered traits don't improve and may even decrease the organism's ability to survive and reproduce, they generally can't spread through wild populations.
Gene drives
Genes can sometimes gain a fitness advantage that doesn't rely on the organism. Most genes in sexually reproducing species have a 50% chance of being inherited by each offspring. But many genes in nature have evolved ways to beat the odds: by being passed on more than half of the time, they gain an evolutionary advantage. This can allow an inheritance-biasing “gene drive” that is initially present in a single individual to spread over many generations until it is present in all members of a population.
One type of gene drive influences inheritance by copying itself onto chromosomes that previously lacked it. When an organism inherits such a gene drive from only one parent, it makes a cut in the chromosome from the other parent, forcing the cell to copy the inheritance-biasing gene drive—and any adjacent genes—when it repairs the damage (see the figure and additional details below).
Now imagine we want to edit a particular gene—say, one controlling the immune response of mosquitoes to malaria. We could make a mosquito with an edited version of this gene and insert the CRISPR system right next to it along with a fragment directing CRISPR to cut the original—but not the edited—gene. When our altered mosquito mates with a wild mosquito, the offspring will inherit one edited and one normal copy. CRISPR will then cut the normal copy and the cell will attempt to repair the cut by copying the edited version and the CRISPR system. The offspring will now have two copies of the edited version plus CRISPR.
This insect will mate with other insects in which the same process of turning the normal genes into edited genes will be repeated. Given enough generations, CRISPR will spread the edited gene through the entire population of mosquitoes—and this is key—even if the edited gene reduces the odds that each mosquito will reproduce.
Since CRISPR can be directed to cut essentially any gene at a precisely determined location and works in every organism we've tested, CRISPR gene drives may allow us to spread nearly any type of genome alteration through many sexually reproducing populations. We describe this possibility in detail in a paper published today in the journal eLife.
Because CRISPR itself is so precise, we can envision a number of safeguards. Alterations can be reversed by releasing a new drive with an updated version of the change. It's effectively a slow-motion “undo” button for genome alterations and could work on any type of change. Similarly, only populations that have the sequence targeted by CRISPR can be altered by a drive, potentially allowing us to target subpopulations with unique sequences. This also means that deliberately altering the sequences needed by another drive can provide protection against it, allowing us to immunize populations against specific drives and their associated changes.
Limitations
There are fundamental limits to what gene drives can do. First, they cannot under any circumstances affect species that reproduce exclusively asexually, because there is no inheritance to bias. Viruses and bacteria are not susceptible, while many plants, fungi, and some animals will be resistant because they frequently reproduce without sex.
Second, gene drives can make only temporary changes. We can use them to spread traits that we consider desirable even if they are deleterious to each organism, but natural selection will eventually undo our best efforts if we give it long enough.
Third and most importantly, gene drives require many generations to spread. We could alter entire populations of fast-reproducing insects in a couple of years—depending on how many we release—but it would take decades or centuries for long-lived organisms. That's why gene drives won't be able to affect human populations without taking centuries. They're also easily detected by genome sequencing and can't spread accidentally through populations in which mate choice is artificially controlled, which greatly limits their potential to affect crops and domesticated species.
Implications
The ability to manage ecosystems by altering wild populations will have profound implications for our relationship to nature. Selective breeding and genome engineering have in many ways defined agriculture, human living and medicine, but have had comparatively little impact on most ecosystems due to the inability of domesticated crops and animals to survive in the wild. With CRISPR gene drives, we may be able to directly alter the traits or influence the population size of many non-domesticated species, which constitute the vast majority of key players in ecosystems worldwide. Given the importance of ecosystem integrity and vitality to human flourishing and the balance of life on our planet, the availability of these techniques will come with tremendous responsibility. The decision of when and where to apply this technology, and for what purposes, will be in our collective hands.
Potential Applications
Why and how might we use gene drives to intervene in a particular ecosystem? Our earlier example is perhaps the most compelling: we might use gene drives to control malaria by altering Anopheles mosquitoes that transmit the disease. Anti-malarial medicines and insecticides are losing effectiveness due to evolving resistance, while a vaccine remains out of reach despite intense research and investment. Gene drives, in contrast, might spread genes conferring malaria resistance through the mosquito populations with few if any effects on other species. Alternatively, they might be able to reduce or even eliminate the mosquitoes for long enough to permanently eradicate the malaria parasite. Similar strategies could work for other organisms that spread disease.
Gene drives might directly benefit biodiversity by controlling populations of environmentally damaging invasive species such as rats, cane toads, or lionfish. Unlike most of our current chemical or biocontrol methods, they would be specific to the target species and might be able to fully eradicate invasive populations. They might also promote more sustainable agriculture by controlling insect pests and reversing herbicide resistance in weeds, thereby supporting no-till farming.
Evaluation
Ecological changes caused by gene drives will be overwhelmingly due to the particular alteration and species, not by the CRISPR drive components. That means it doesn't really make sense to ask whether we should use gene drives. Rather, we'll need to ask whether it's a good idea to consider driving this particular change through this particular population. While gene drives could tremendously benefit humans and the environment if used responsibly, the potentially accessible nature of the technology raises concerns about the risks of accidental effects or even intentional mismanagement. In a new paper published in Science, we specifically address the regulation and risk governance of gene drive applications to promote responsible use.
The recent ecological concept in ethics may provide a framework for analysis and decision-making that can accommodate for a broad spectrum of moral values and worldviews.
Conclusion
The ability to alter populations and ecosystems using gene drives is around the corner—but not yet here today. As scientists and bioethicists, we have a professional obligation to inform society of the potential consequences of our work as early as possible. We judged the eventual development of RNA-guided gene drives to be inevitable due to the landmark theoretical work by Austin Burt, who first described the possible uses of endonuclease gene drives more than a decade ago, and the rapid advancement of CRISPR-based genome editing. After extensive discussions with experts in many fields, we elected to publish our findings in order to provide time for informed public discussion, regulatory review, and the establishment of guidelines for the safe development of the technology.
Because we are all affected by the state of our ecosystems, public oversight of technologies capable of ecological management will be essential. We recommend that all future research involving gene drives and other technologies capable of altering populations and ecosystems be conducted in full public view, with all empirical data and predictive models freely and openly shared with the global community in a transparent and understandable format. Only through broadly inclusive and well-informed public discussions can we as a society decide how best to manage our shared environment. We hope that many of you will join.
George Church is a member of Scientific American's Board of Advisors
-----------------------------
How Endonuclease Gene Drives Work
Gene drives for ecosystem management (click to enlarge)
Standard drives spread introduced genes or specific patterns of genome changes through populations. They might be used to drive a gene that interferes with the spread of a disease, such as an anti-malarial peptide, or to disrupt a natural gene important for disease spread.
Suppression drives reduce the number of organisms in a target population. Naturally occurring suppression drives are always found together with a resistance element that allows the species to survive. It is believed that the emergence of drives in the past may have driven species all the way to extinction when resistance did not develop in time. There are many different ways to build a suppression drive, some of which have quite different effects. They could be used to control the populations of environmentally destructive invasive species such as mosquitoes, rats, cane toads, or lionfish that currently threaten many ecosystems. They might even be able to render pest populations uniquely vulnerable to molecules that don't affect other organisms.
Reversal drives undo earlier genome changes caused by natural evolution, human-inserted transgenes, earlier gene drives, or even naturally evolved mutations such as those conferring pesticide or herbicide resistance in pests and weeds.
Immunization drives immunize existing populations to prevent them from being affected by other gene drives.
Precision drives can only spread alterations through populations of organisms that have a unique DNA sequence.
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