Gene-editing technology to create virus-resistant cassava plant has opposite effect, researchers find

Gene-editing technology to create virus-resistant cassava plant has opposite effect, researchers find
Diseased (left) and healthy (right) cassava plants. Researchers are urging caution with using CRISPR gene-editing technology on the plant after their attempt to produce a virus-resistant variant resulted in mutated viruses that are resistant to gene editing. Credit: Hervé Vanderschuren

Using gene-editing technology to create virus-resistant cassava plants could have serious negative ramifications, according to new research by plant biologists at the University of Alberta, the University of Liège in Belgium and the Swiss Federal Institute of Technology.

Their research shows that attempts to genetically engineer the to fight off viruses resulted in the propagation of mutated viruses in controlled laboratory conditions.

"Because this technology creates a selection pressure on the viruses to evolve more quickly, and also provides the viruses a means to evolve, it resulted in a virus mutant that is resistant to our interventions," explained U of A post-doctoral fellow Devang Mehta.

The researchers used a new gene-editing technology called CRISPR-Cas9 in an attempt to design plants that could cut the DNA of the mosaic virus and make the plants resistant to its damaging effects. They weren't successful and decided to sequence hundreds of viral genomes found in each plant to understand exactly what happened.

"We discovered that the pressure that CRISPR-Cas9 applied to the virus probably encouraged it to evolve in a way that increased resistance to intervention," said Mehta, who noted CRISPR-Cas9 has many other applications in food and agriculture that do not pose the same risks.

CRISPR-Cas9 is found in nature, where bacteria use it to defend against viruses. However, the researchers found the technology results in different outcomes in plants—and researchers are stressing the importance of screening against these sorts of unintended results in the future.

The cassava plant is a starchy root vegetable that is consumed for food throughout the tropics. Cassava is a primary staple crop grown in South America, Africa and Asia, from which a billion people get most of their calories each day. Each year, cassava crops are plagued by cassava mosaic disease, which causes 20 per cent crop loss. It is the mosaic disease that Mehta and his colleagues endeavoured to engineer against.

The research team is encouraging other scientists who are using CRISPR-Cas9 technology to engineer -resistant plants, to test their plants to detect similar viral mutations.

"We need to do more research on these types of applications of CRISPR-Cas9 before we proceed with ," said Mehta.

The study, "Linking CRISPR-Cas9 Interference in Cassava to the Evolution of Editing-Resistant Geminiviruses," was published in Genome Biology.


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A light-based carrier system for CRISPR-Cas9 gene editing

More information: Devang Mehta et al. Linking CRISPR-Cas9 interference in cassava to the evolution of editing-resistant geminiviruses, Genome Biology (2019). DOI: 10.1186/s13059-019-1678-3
Journal information: Genome Biology

Citation: Gene-editing technology to create virus-resistant cassava plant has opposite effect, researchers find (2019, April 26) retrieved 18 July 2019 from https://phys.org/news/2019-04-gene-editing-technology-virus-resistant-cassava-effect.html
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Apr 26, 2019
When you screw around with the building blocks of life without really knowing what you're doing or the consequences of your ham-fisted bumbling, something is bound to go wrong. We need much stricter regulation of this relatively new and untested technology. It should be obvious by now that we are playing with fire and have no water available if things go sideways.

Apr 27, 2019
A 20% crop loss of Cassava plants per year is not a good enough reason for scientists to mess with Mother Nature. Surely they must have understood that the stress of the virus on the plants will cause them to develop new resistance to the disease and could eventually make the new crops stronger? That is how evolution works.
There is such a thing as "letting dogs lie" if one doesn't want to be bitten. In this case, the euphemism applies to scientists who are emulating the Doctor Frankenstein model while trying to improve the dying body. The plants that die from the virus are the sacrifice that preserves the health of the other 80% of the year's crop. They wished to create a quick panacea to prevent future ills of Cassava, but only resulted in creating a monster. Hopefully, they were able to CONTAIN and destroy that monster before it spreads.

Apr 27, 2019
Pussytard plops a big one
not a good enough reason for scientists to mess with Mother Nature. Surely they must have understood
"The progenitor of cassava (M. esculenta ssp. flabellifolia) exists today and is adapted to forest and savanna ecotones. The process of domestication improved the size and production level of its tubers, and increased the photosynthesis rate and seed functionality, by using repeated cycles of clonal propagation—wild manioc cannot be reproduced by stem cuttings... Identification of the Amazon as the point of origin was based on genetic studies of cultivated cassava and all various possible progenitors, and the Amazonian M. esculenta ssp. flabellifolia was determined to be the wild form of today's cassava plant."

-Cassava is an artificial plant you fucking moron.

Apr 27, 2019
"...Using gene-editing technology to create virus-resistant cassava plants could have serious negative ramifications, ..."

Only if you do it wrong. Obviously the trick is to do it right. This article, along with the usual moronic anti-GM propaganda, is STUPID. I just cannot stand this moronic "musn't mess with Mother Nature" ideology, as if anything we humans touch or change will be magically cursed as a result. We and all life forms on Earth are genetically engineered! By evolution! So why would it necessarily be a bad thing if we also did it? What is natural is often bad and what is unnatural is often good. Rabies is natural and bad. A life-saving designer drug is unnutural and good.

Apr 27, 2019
Another pinhead opines
When you screw around with the building blocks of life without really knowing what you're doing
That's the definition of domestication isnt it? Humans have been domesticating themselves for a million years in the context of the tribe.
genetically engineered! By evolution!
Domestication is not evolution. Artificial selection is not natural selection.

Apr 27, 2019
And apparently, domestication is a reason that these plants are susceptible to the virus.

"So far, the most successful approach used to control these viruses has been the transfer of a polygenic recessive resistance locus, designated CMD1, from wild cassava to cassava cultivars. Further progress in harnessing natural resistance to contain CMGs has come from the discovery of the dominant monogenic resistance locus, CMD2, in some West African cassava cultivars."

Apr 27, 2019
TheGhostofOtto1923
I just said "genetically engineered", NOT "domestication"
Domestication is not evolution.
Genetically engineered isn't domestication. And I didn't imply/believe domestication and/or genetically engineered is evolution.
Artificial selection is not natural selection.
Genetically engineered isn't necessarily consisting of artificial selection. And I didn't imply/believe domestication and/or genetically engineered is natural selection.

Apr 27, 2019
-although I DID imply evolution 'genetically engineered', that is giving a very none-standard meaning to the term 'genetically engineered' that doesn't imply intent involved. Obviously, that's not the normal or usual meaning of the term. But, using NONE-standard meanings, we can say "Evolution is nature's geneticist".

Apr 27, 2019
-although I DID imply evolution 'genetically engineered', that is giving a very none-standard meaning to the term 'genetically engineered' that doesn't imply intent involved. Obviously, that's not the normal or usual meaning of the term. But, using NONE-standard meanings, we can say "Evolution is nature's geneticist".
says humy

Certainly, you are correct in the above that evolution is nature's geneticist. The process of evolution in plants and animals has been happening since the first life forms developed in the waters of this planet.

"-Cassava is an artificial plant you fucking moron." says the Nazi arsehole

There are plants that can be eaten by animals (including humans) and other life forms. If it can be consumed by such life forms, it isn't artificial. Hybrids are those plants whose genetics have been changed, either by humans or nature. In Nature, it is most often done slowly and depend on several factors such as climate and resources.

Apr 27, 2019
"...Using gene-editing technology to create virus-resistant cassava plants could have serious negative ramifications, ..."

Only if you do it wrong. Obviously the trick is to do it right. This article, along with the usual moronic anti-GM propaganda, is STUPID. I just cannot stand this moronic "musn't mess with Mother Nature" ideology, as if anything we humans touch or change will be magically cursed as a result. We and all life forms on Earth are genetically engineered! By evolution! So why would it necessarily be a bad thing if we also did it? What is natural is often bad and what is unnatural is often good. Rabies is natural and bad. A life-saving designer drug is unnutural and good.

says humy

There are some things that need to be thwarted such as rabies, viruses and other diseases. But now the proof is there that science has messed up and the Cassava virus has become healthier and stronger. That will threaten the future healthof Cassava plants that are eaten by humans.

Apr 27, 2019
But now the proof is there that science has messed up and the Cassava virus has become healthier and stronger.
If that is true then the solution is to let science GM Cassava to be permanently completely immune to the virus and for all credible mutations the virus can have thus preventing it ever again evolving to be stronger. It must be possible and the science of genetic engineering is improving all the time thus its just a matter of when, not if, thus can and will happen.

Apr 27, 2019
I have thought of a way to GM all our crop plants and even ourselves to be permanently completely immune to all virus, both known and unknown ones. Its just a matter of changing the genetic codon language of our DNA. That way if any natural virus invades the cell, its DNA will be now written in the wrong language and will be mistranslated into arbitrary non-functional garbage chains of amino acids instead of functional viral proteins and no credible mutation of the virus could completely transform all of its essential genes to suddenly be written in the new language. We can only do this wonderful thing if we allow GM.

Apr 27, 2019
"But now the proof is there that science has messed up and the Cassava virus has become healthier and stronger. That will threaten the future healthof Cassava plants that are eaten by humans."

Ha! You should maybe try reading sometime: "controlled laboratory conditions".

Apr 27, 2019
I just said "genetically engineered", NOT "domestication"
Domestication is not evolution
Genetically engineered isn't domestication. And I didn't imply/believe domestication and/or genetically engineered is evolution.
Artificial selection is not natural selection.
Genetically engineered isn't necessarily consisting of artificial selection. And I didn't imply/believe domestication and/or genetically engineered is natural selection
And I wasnt calling you a pinhead. Not many pros make a distinction. Few recognize our own domestication.
Certainly, you are correct in the above that evolution is nature's geneticist
-Says the clueless imbecile who also tends to say things like
"We have not grown a third eye, a huge skull and much larger brain than what we already have, nor have we evolved to reproduce by splitting into two equal parts similar to amoebae"
-So much fun to pretend isnt it? Do you also have a lab coat with 'pussytard' embroidered on it?

Apr 27, 2019
Its just a matter of changing the genetic codon language of our DNA
Yes, because little mounds of goo rarely get sick. And if they do, how can you tell, really?

Jesus christ.
There are plants that can be eaten by animals (including humans) and other life forms. If it can be consumed by such life forms, it isn't artificial
-And I remember when you pretended to own a sweet sorghum farm. And you were a black psychiatrist. And also a NASA engr who had many patents.

Do we need to feel sorry for such extremely demented people, or confront them with their own sickness? Mods dont seem to care. Traffic is traffic I suppose.

Apr 28, 2019
@TheGhostofOtto1923 - I have noticed in your postings that you often make quite valid and reasonable scientific points. I suspect if you weren't so caustic and free with your name calling you would generate a lot more respect than you obviously do (as based on your down-votes).

Apr 28, 2019
@TheGhostofOtto1923 - I have noticed in your postings that you often make quite valid and reasonable scientific points. I suspect if you weren't so caustic and free with your name calling you would generate a lot more respect than you obviously do (as based on your down-votes).
You've been around a long time. Perhaps you're not familiar with this particular individual, who has posted 1000s of posts under many socks such as pirouette, pussycat_eyes, russkiye, obama_socks, racistblackguy, jewsrule, etc. Initially myself and many others respond politely and logically to this troll and others but it always escalates in response to general disrespect and ignorance.

Continued shaming and insults seem to be the only way of getting rid of them. I am certainly not the only one who does this and I am sure you know this.

People who make up facts, play games, disrespect science, and flood the site with inanity have no place here. Once exposed they can expect no peace.

Apr 28, 2019
Ha I just had a similar encounter. I heard this thumping and went outside. There was a canadian goose attacking its reflection in a window in the building next door, about 30 yards away. I yelled 'Hey bird!' and it turned and looked at me. 'Yeah you!' I yelled. 'Stop it.' It honked and started walking away. It hesitated and I yelled 'Keep going. Stupid bird!' and it waddled off. At least for now.

See that's the difference between natural and artificial.

Apr 29, 2019
@TheGhostofOtto1923:

Don't be so dishonest. Aside from any failings, both real and imagined, of your chosen adversaries, you are quite simply a pathologically pugnacious person - you deliberately pick fights and arguments, simply for the sake of it. I have seen you derange topics without any further provocation than someone not wholeheartedly accepting your views, and I have personally had you call me weak and similar things for refusing to continue with a fruitless argument over the relative size-to-weight-ratio of early- and high medieval swords, illustrating that you are in it for the thrill of the fight.

Apr 29, 2019
@TheGhostofOtto1923:

Don't be so dishonest...you are quite simply a pathologically pugnacious
You forgot Pusillanimous and Perspicacious and parsimonious.
person - you deliberately pick fights and arguments, simply for the sake of it. I have seen you derange topics without any further provocation than someone not wholeheartedly accepting your views, and I have personally had you call me weak and similar things for refusing to continue with a fruitless argument over the relative size-to-weight-ratio of early- and high medieval swords, illustrating that you are in it for the thrill of the fight

-Kind of like the goose who attacks its reflection in the window? Tell me to go away and see what happens.

Youve been around a long time too. Youre fully aware of the asshole known as pirouette, pussycat_eyes, russkiye, obama_socks, racistblackguy, jewsrule. You defend her because you ARE weak. Show a backbone and criticize liars and vandals.

Apr 30, 2019
See? There you go again. I'm not defending anyone, I'm talking about YOUR issues. And you turn it into a chance to fight.

Apr 30, 2019
See? There you go again. I'm not defending anyone, I'm talking about YOUR issues. And you turn it into a chance to fight.
-It was a REASON to fight, not a chance.

You're attacking me because I attacked someone else, whether they deserved it or not. And you do so for selfish reasons, because I have attacked you in the past for similar reasons.

If you were honest you would acknowledge that this troll deserves to be attacked for the garbage she regularly posts, instead of taking the opportunity to make it about you.

Apr 30, 2019
Double post

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