What is CRISPR? Animation.

What is CRISPR? Animation.

CRISPR is the newly discovered REVOLUTIONARY
tool that would allow scientists to change AT WILL any DNA sequence of, presumably, any
living organism in a precise manner. Unlike any other previously developed techniques
of gene editing, CRISPR is REMARKABLY simpler, faster and cheaper.
CRISPR is part of a naturally occurring defense mechanism found in many bacteria. The bacteria
use CRISPR to SPECIFICALLY snip the DNA of invading viruses. CRISPR stands for “Clustered
Regularly Interspaced Short Palindromic Repeats” – a region of bacterial genome that contains
short DNA repeats with unique sequences, or spacers, in between. These spacers are derived
from DNA of viruses that prey on the bacteria. The CRISPR region is essentially a DNA library
of all enemies that need to be RECOGNIZED and destroyed. After being transcribed, individual
pieces of spacer RNAs form complexes with a protein named Cas, for CRISPR-ASsociated
protein. Cas is an endonuclease – an enzyme that cuts DNA. These RNA/protein complexes
then drift through the cell, looking for matching viral DNA. If a match is encountered, the
RNA latches on, base-paring with it; Cas protein then cuts the viral DNA, disabling the virus.
Scientists have isolated this system, and by designing their own spacer-RNAs, they can,
in theory, target any DNA sequences in any organism. The system has indeed worked in
all organisms tested so far. The current CRISPR system consists of two components: a guide
RNA and a Cas protein named Cas9. The guide RNA is a short synthetic RNA composed of a
“scaffold” sequence necessary for Cas9-binding and a user-defined “spacer”, or “targeting”
sequence of about 20 nucleotides long. One can change the genomic target of Cas9 by simply
changing the targeting sequence present in the guide RNA. The entire system is designed
in a plasmid that is subsequently used to transfect living cells.
Some applications of the CRISPR system include: – Disabling, or knock-out, a particular gene:
After Cas-9 cuts the DNA, the cell would try to repair the break. The more efficient repair
pathway in the cell is ERROR-PRONE and would most likely result in a loss-of-function mutation
in the gene of interest. As CRISPR modifies BOTH copies of the gene at the same time,
generation of knock-out animals and cell lines for gene function studies has never been more
efficient. Moreover, MULTIPLE genes can be targeted in one manipulation, making this
technique an extraordinarily powerful tool for studying complex genetic traits or diseases
that involve many genes, such as cancers. – Introducing precise modifications to the
target DNA: If a desired DNA sequence is provided together with the CRISPR/Cas-9 system, it
can be used by ANOTHER repair pathway as a TEMPLATE to reconstruct the disrupted gene
sequence. The desired changes stay permanently and are also transmitted to future generations.
This can be used, for example, to swap a mutated copy of a gene with the good version, thereby
restoring the gene’s function. – Modifications to the Cas9 enzyme have extended
the application of CRISPR to selectively turn ON and OFF target genes, fine-tune their expression
WITHOUT permanently altering the gene sequence. Since its discovery, CRISPR technology has
been used extensively in animal research to engineer disease-resistant livestock; bring
back extinct species; introduce deleterious genes into malaria-carrying mosquitoes; and
modify pig genome to make pig’s organs suitable for transplant into human. Due to its relative
simplicity, CRISPR has also been employed to create “custom designed” pets such
as mini-pigs with customized coat patterns, colorful koi fish and dogs with certain desirable
traits. The CRISPR zoo is growing rapidly but so are the ethical concerns and fears
of possible ecological disasters. In human, while CRISPR is proven to be a powerful
tool to study various diseases, it is deemed NOT YET ready for clinical applications. This
is because the Cas enzyme occasionally still cuts in the wrong place and hence cannot be
used to introduce permanent changes to people. Modification of human germlines to alter genetic
heritage of future generations may also lead to unwanted far-reaching consequences and
is prohibited by most countries.

David Anderson

Related Posts

23 thoughts on “What is CRISPR? Animation.

  1. TeddyVoodoo says:

    Thanks to this video I finally understood how to edit the genom, as it's part of a presentation I have to prepair.

  2. CryonicsInstitute says:

    It would be interesting to use deep learning and advanced AI to tease out crispr tools…such as editing of the human genome to replace disease and aging with the genes that code for health and longevity.

  3. Aboreus says:

    Can the targeting sequence for the guide RNA be less than 20 nucleotides long?


    My grandaughter has a defective gene which causes cancer in your twenties, both her mother and grandmother died of cancer in their twenties, can this work to remove defective genes after birth.

  5. Friedrich Will says:

    Great job. Really nicely done introductory video! I studied molecular bio in college but have been out of the field for years. This video reminds me of my college days. Very interesting and nicely done

  6. sanderson alberto says:

    Why not an autologous bone marrow
    transplant using the patient's own stem cells that have been modified
    using CRISPR /Cas9 to impart the gene for HIV resistance?

  7. IAMTHEO says:

    could it fully cure a genetic disease in a human being ?

  8. Imagination At Work says:

    whats difference between cas and cas9?
    correct me if i am wrong
    cas is the gene and cas9 is the nuclease that binds with viral dna and cuts it

  9. Tundrus says:

    So people cannot really be cured from genetic diseases this way right? The only way to stop the death from a genetic disease would be from editing it at birth so when the stem cell splits, it will be contained in all of the cells throughout the body. Is this correct? If so, the future generation will be pretty lucky.
    Another question. Could you make the changes to the gene permanent? I know the video said the edited genes may not be permanent, but is it possible to pass on a gene that has been repaired?

  10. Alila Medical Media says:

    Thank you for watching! Follow us on Twitter https://twitter.com/AlilaMedical for instant notification of our new videos!

  11. Why Not CR says:

    Nice video. Keep it up

  12. Kevin Pham says:

    does the crispr/cas9 system do the insertion of the desired gene or is that another system? What handles that part of the procedure?

  13. Ferry Jap says:

    Which hospital is ready to use CRISPR??

  14. Hambal Uba says:

    this new technology is more interesting and it will get better soon the science to be more confident on biotech

  15. Billy Willy says:

    Not really sure whether we'll destroy the plant with nuclear weapons or CRISPR in the hands of ideologues and idiots. Kind of a tossup at this point.

  16. charge61 says:

    This is the greatest discovery in all of human history. God like powers are now in our hands and this science is still n it's infancy. The question is, will we eventually destroy ourselves by basically creating our own extinction. CRISPR is irreversible and all consuming. Once the genie is out the bottle there is no getting it back in when it comes to CRISPR genetic manipulation.

  17. Em Miller says:

    The animation was extremely helpful, and the voiceover (while sounding like a serial killer) was useful to help explain the process of how CRISPR works.

  18. Alila Medical Media says:

    Help us make more videos like this! Support us on Patreon and get FREE downloads and other great rewards: https://www.patreon.com/AlilaMedicalMedia/posts
    Thank you so much!

  19. Rahul Paul says:

    Is it possible to change skin color genetically?

  20. Workdove says:

    God only knows what this will end up doing to the environment- isn't it bad enough as it is?

  21. Justin D'murcielago says:

    gotta love bio engineering. they only say not with humans LOL.

  22. A normal guy With a beard says:

    Your are invited to join LinkedIn “CRISPR Forum” group: https://www.linkedin.com/groups/5064109

  23. Chupria says:

    Come over to crisprcas9cure dot com. I am trying to spread the word about crispr cas9. Looking to do a public stunt!

Leave a Reply

Your email address will not be published. Required fields are marked *