Gene Drives: Conservation Savior or Mad Science?

Gene Drives are a new technology that radically skew inheritence probabilities in favor of the introduced genes using CRISPR to insert the gene and then to copy in into the unaffected allele in the offspring. This process increases of the probability of passing the gene from 50% to 100%. Most people have heard of this technology in its use on mosquito populations to eradicate malaria. Using gene drives we could introduce genes that would create population of plants that are pesticide resistant or animals that are more adapted to city life within a few generations instead of hundreds of years if at all...but is this ethical? We could accidentially kill a whole species if a target population escaped into other habitats or we could create more super bugs as plants and animals evolved resistence. Will this technology become the superhero of the conservation field? Or will the potential consequences eradicate gene drives instead of mosquitoes?

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https://baynature.org/article/re-coding-conservation/An adorable comic from an amazing article found here: 

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Amazing image explaining gene drives found at https://www.islandconservation.org/economist-features-island-conservation-promise-peril-gene-drives/

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A article looking at eradicating a species other than mosquitoes.

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Taking a scientific look at the “silver bullet” of conversation: gene drives and how they need to be carefully controlled to avoid disaster.

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Opinion: Is CRISPR-based gene drive a biocontrol silver bullet or global conservation threat?

Scientists have recognized the potential for applying gene drive technologies to the control of invasive species for several years (1, 2), yet debate about the application of gene drive has been primarily restricted to mosquitoes (3). Recent developments in clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 technology have restarted discussions of using gene drive for invasive species control (4)...

This PNAS article lays out the issues with gene drives and looks at some other applications for the technology as well!

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Scientists working in the vanguard of new genetic technologies have issued a cautionary call to ensure that possible applications in conservation will only affect local populations. Experts have now examined the possible consequences of the accidental spread of existing self-propagating gene drive systems.

New Zealand is looking to use gene drives on species outside of just mosquitoes

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Gene editing can now change an entire species – forever | Jennifer Kahn

 CRISPR gene drives allow scientists to change sequences of DNA and guarantee that the resulting edited genetic trait is inherited by future generations, opening up the possibility of altering entire species forever. More than anything, this technology has led to questions: How will this new power affect humanity? What are we going to use it to change? Are we gods now? Join journalist Jennifer Kahn as she ponders these questions and shares a potentially powerful application of gene drives: the development of disease-resistant mosquitoes that could knock out malaria and Zika.

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In September 2018, a research team at Imperial College, London, led by Andrea Crisanti and featuring pioneer Austin Burt, revealed it had generated a CRISPR gene drive that caused a total population collapse in lab-bred Anopheles gambiae mosquitoes.

The researchers targeted a gene known as doublesex, which acts like a gatekeeper that decides whether a mosquito becomes a male or a female. By altering this gene, the team was able to breed female mosquitoes that were infertile and had mouthparts that could not draw blood. In essence, they flipped a genetic switch that caused females to develop more like males.  

After starting with 600 mosquitoes, the gene drive spread through the population within 7 to 11 generations, causing a total collapse. The research team had created a similar drive in 2015 targeting a different gene, but it hadn’t been as successful in crashing the population because genetic mutations arose over time. This, then, was the most powerful drive yet. (x)

Per this article on CRISPR machines, In theory, we could eliminate species that are harmful to humans. In practice, will it work? Should we do it? 

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Today the World Health Organization called Zika virus a “public health emergency of international concern.”

Zika, like many other illnesses, is spread by mosquitoes. And a new genetic technology called the CRISPR gene drive, could potentially keep mosquitoes from transmitting a disease, or eradicate a population of mosquitoes altogether.

The question now is: Should we use it?

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GM mosquito trial sparks ‘Sorcerer’s Apprentice’ lab fears

Burkino Faso malaria test raises stakes at UN biodiversity conference

“Thousands of genetically modified mosquitoes are to be released in Burkina Faso as a step towards the world’s first field test of “gene-drive” technology.The trial, which has been funded by organisations linked to the Gates Foundation, Facebook, and – indirectly – the Pentagon, is part of a project to eradicate malaria, but it has prompted concerns among local civil society organisations, who say their country is being set up as a laboratory for “Sorcerer’s Apprentice” technology before the risks are fully understood.“

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Gene drives thwarted by emergence of resistant organisms

Until this obstacle is overcome, the technology is unlikely to succeed in the wild.

A test population of mosquitoes developed resistance to CRISPR by changing the target DNA sequence. Hurdles like evolution of immunity are very interesting but also slow down the development of gene drives. 

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‘Gene drive’ moratorium shot down at UN biodiversity meeting

Freeze on genetic technology would have been a disaster, say scientists, but activists plan to renew the fight.

The debate on whether or not this technology is useful or too dangerous has wins and loses on both sides. What do you think about this new technology?

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A CRISPR-Cas9 gene drive system targeting female reproduction in the malaria mosquito vector Anopheles gambiae

Development of a CRISPR/Cas9-based gene drive system in Anopheles gambiae, the main vector for the malaria parasite, paves the way for control of this pest insect.

“Gene drive systems that enable super-Mendelian inheritance of a transgene have the potential to modify insect populations over a timeframe of a few years” (Hammond et al., 2016).

This article’s first sentence nails the issue on the head of why gene drives are so attractive and so potentially dangerous.

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CRISPR-Cas9: Gene Drives from Wyss Institute on Vimeo. This amazing video by Wyss institute shows the mechanisms behind gene drives and how a single copy of a single gene can take over a whole population.

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A pedigree figure showing how gene drives are intended to work. If remember from high school biology, alleles (copies of genes) are equally as likely to be inherited by the next generation. Gene drives skew the probability in their favor. Ensuring that the allele is passed on from one generation to the next, rapidly increasing frequency in a population. 

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New technologies have played an important role in protecting life on earth, and we the undersigned support innovation and science in conservation. However, we believe that a powerful and potentially dangerous technology such as gene drives, which has not been tested for unintended consequences nor fully evaluated for its ethical and social impacts, should not be promoted as a conservation tool.

These notable scientists have come down on the side of being against gene drives.  

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US defence agencies grapple with gene drives

National security community examines the risks and benefits of technology to quickly spread genetic modifications.

“The JASONs, a group of elite scientists that advises the US government on national security, has weighed in on issues ranging from cyber security ​to renewing America’s nuclear arsenal. But at a meeting in June, the secretive group took stock of a new threat: gene drives” (Callaway, 2017).

Many scientists are picking sides of this issue some for and some against. Will this be a conservation tool of the future?