Wednesday 9 September 2020

Przewalski's horse cloned for genetic diversity

In 2015 I proposed cloning as a chance for the wisent's survival. Cloning pre-bottleneck wisents would greatly increase the genetic diversity of the species, since the modern population descends from a population of only about 50 individuals which itself descended from only 12 individuals. Adding the genetic diversity of wisents that lived before the dramatic bottleneck event in the 20th century would help the species to overcome its inbreeding depression. And if cloning is not possible, genome editing with CRISPR-Cas9 is a viable alternative. 

It seems that there are people who had the same idea for the Przewalski's horse, which descends from only 12 individuals as well. A stallion has been cloned from an individual that has been cryopreserved since 1980. For details, you can have a look at the article from Revive & Restore. 

I hope that cloning for conservation will not be restricted to this one individual. I hope this idea will be put into practice for other species as well, including the wisent. 

11 comments:

  1. As far as I know, there is no wisent material available from cryopreserved specimens, and consequently no living cells from which to make a clone. As such the CRISPR method is probably the only option. DNA from museum specimens or other sources could theoretically be procured, but the process for adding diversity would be different. If pre-bottleneck alleles could be identified that are absent from the modern wisent population, these could be manually inserted into a living cell line one at a time using CRISPR. The resulting embryo could then be brought to term. The downside there is just that it would be more difficult than traditional cloning. It would be much more practical to attempt genetic rescue through American bison introgression.

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    1. More practical but also a lot more controversial.

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    2. If we were creating true clones of living tissue then I would agree, but I think genetic engineering is pretty controversial in its own right

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  2. Be very careful with gene editing, unwanted consequences can pollute entire species.

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  3. I don't understand how introgression of Bison and cattle genes to supplement pre-bottleneck Wisent genes (considering the Wisent basically being a Bison Aurich hybrid) would be more controversial than the risky, complicated human endeavor of gene editing; in consideration that the former has been sanctioned by nature and the latter is a largely untested frontier

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  4. Does anyone here know if the cloned Przewalski horse represents an individual that isn't one of the founders? I get the impression the cloned individual was an ancestor of existing Przewalskis, which means the cloning process is simply bringing back the portion of his genome not passed on in his original progeny.

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  5. They should also clone the Asian lion to increase genetic diversity as the 600 Asian lions that exist today are descended from a small group of 20/30/40 lions

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  6. They should also clone the Asian lion to increase genetic diversity as the 600 Asian lions that exist today are descended from a small group of 20/30/40 lions

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  7. The world’s first successfully cloned Black-footed ferret has been born:
    https://reviverestore.org/projects/black-footed-ferret/
    https://www.youtube.com/watch?v=hJfDhMdCqug

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  8. Przewalski's horse:
    http://przewalskihorse.nl/
    https://www.takh.org/en/

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  9. Passenger Pigeon, etc.:
    https://reviverestore.org/
    https://reviverestore.org/about-the-passenger-pigeon/
    http://passengerpigeon.org/

    http://www.bucardo.es/

    https://www.quaggaproject.org/
    https://quaggaproject.org

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