CRISPR is a family of DNA sequences found within the genomes of prokaryotic organisms such as bacteria and archaea. These sequences are derived from DNA fragments from viruses that have previously infected the prokaryote and are used to detect and destroy DNA from similar viruses during subsequent infections.

1. C R I S P R
A New Era of Genome Editing !
A Presentation By Ali Ahmadi , MSc of Nanobiotechnology, University of Tehran, Tehran,
Iran. E-Mail : Ali.ahmadii@ut.ac.ir
Course : Molecular Biotechnology | Instructor : Mahdi Rahaie, PhD
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2. Contents/Terminology
A Brief Introduction To Viral Pathogenesis
Bacteriophage Interference
A Brief History of Genome editing
What is CRISPR-Cas9 : A New Era of Genome Editing !
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3. A Brief Introduction To
Viral Pathogenesis
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4. Either Lytic or Lysogenic
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5. Bacteriophage Interference
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7. A Brief History of Genome editing
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8. Genome editing techniques make use of certain
proteins that can cut DNA in a precise,
targeted location. This family of proteins was
discovered in the 60s.
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9. How to Improve my Eye Sight
Quality ?
How To increase
My Lifetime?
I Want To Fly !
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10. Genome Editing Basic Stages :
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11. Mission Completed !
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12. What is CRISPR-Cas9 :
A New Era of Genome Editing !
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13. History
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14. Mojica’s theory (90s) was experimentally
demonstrated in 2007 by a team of
scientists led by Philippe Horvath.
In January 2013, the Zhang lab published
the first method to engineer CRISPR to edit
the genome in mouse and human cells.
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15. - CRISPR stands for Clustered Regularly
Interspaced Short Palindromic Repeats.
- it is a series of short repeating DNA
sequences with “spacers” sitting in between
them.
- RNA made from these spacers can bind to
invading DNA or RNA from viruses or other
pathogens.
- “Cas (cas9)" detects these bound fragments
and cuts the DNA to inactivate the gene. 1
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16. A defining feature of the bacterial genetic
code and its immune
system, functioning as a defence system
that bacteria use to protect themselves
against attacks from viruses. Reminds Us
The RNAi Mechanism (miRNA, siRNA).
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18. How Does it Work for Human being ?
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19. The 3 key players that help the CRISPR-
Cas9 tech do its work:
1.Guide RNA: a piece of RNA (a genetic
cousin of DNA) that locates the targeted
gene. This is engineered in a lab.
2.CRISPR-associated protein 9 (Cas9):
the “scissors” that snip the undesired
DNA out.
3.DNA: the desired piece of DNA that is
inserted after the break.
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21. Applications
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22. Any disease caused by a genetic mutation
Inherited diseases could be possibly
avoided by genetic modifications to
embryos or sperm and egg cells from
parents
Cancer
Sickle-cell anaemia
cystic fibrosis
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23. As An Instance
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27. Q & A
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28. References
Nature Methods : https://www.nature.com/nmeth
Broad Institute : https://www.broadinstitute.org/what-broad/
areas-focus/project-spotlight/questions-and-answers-about-
crispr
http://curiousaboutscience.net/crispr-factsheet-know-
genome-editing/
https://courses.lumenlearning.com/microbiology/chapter/
the-viral-life-cycle/
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29. Hope You Enjoyed !
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