CRISPR/Cas9 Flashcards
(30 cards)
What is genome editing?
The intentional modification of an organism’s DNA at a specific location
What systems are powerful tools for genome editing?
CRISPR/Cas
What does CRISPR/Cas enable?
High efficacy targeting of nearly any site in the genome
What is the main Cas enzyme that people use?
Cas9 - Streptococcus pyogenes
What does Cas9 do exactly?
It complexes with RNAs that enable it to localize to specific locations in a genome and it has domains in it that can cleave nucleic acids
How do you program Cas9?
Program it with appropriate guide RNA and it will bind to a specific part of the genome and cleave a double strand break (DSB)
2 ways DSBs can be repaired?
With a donor DNA template
Nonhomolgous End Joining
What are the 3 types of Nonhomolgous End Joining
It can randomly:
Do a small insertion
Substitution
Small deletion
Basically put what CRISPR/Cas9 is for
You produce a double strand break in a location of the genome you want to change and then repair those breaks with genetic changes…
Can be used to fix diseases
What in Cas9 designates where it will go in the genome?
The protospacer
What is a PAM and why is it required?
What is the sequence?
Protospacer adjacent motif
It helps signal where cas9 can attach
“N”GG
N= any nucleotide
Who were the three principal investigators whose labs figured out how to use CRISPR/Cas systems to edit genomes?
Jennifer Doudna - Intellia
Emmanuelle Charpentier - CRISPR Theraputics
Feng Zhang - Editas
Name the three companies that are the first to attempt CRISPR/Cas-based genome editing therapies in humans
Editas, LCA10, in vivo
Intellia, ATTR amyloidosis, in vivo
CRISPR Theraputics, Sickle cell and B-thalessemia, ex vivo
Who started Editas?
Feng Zhang
What genetic disorder did Editas initially target?
EDIT 101: LCA10, in vivo
Also, EDIT-301 SCD
What is LCA and SCD?
Leber congenital amaurosis
and sickle cell disease
What is LCA10?
it is the most common form of Leber congenital amaurosis
What are 2 factors that contribute to EDIT 101 efficacy?
The retina is accesible to injection and since rods and cones do not divide, there is low risk for triggering genome instability and cancer.
What diseases does CRISPR Theraputics target?
Sickle Cell Disease and Beta-Thalassemia
What is the CRISPR Tx program that targets SCD and B-Thalass.
CTX001 / Exa-cel
What does CTX001/Exa-cel do at the molecular level?
It turns the fetal hemoglobin gene (HbF) back on to represses broken adult hemoglobin gene (HbA)
What disease does Intellia Theraputics target?
ATTR Amylodiosis
What is ATTR Amyloidosis?
Accumulation of misfolded TTR which affects nerves, heart, kidneys and eyes.
What program at Intellia targets ATTR Amyloidosis?
NTLA-2001
