Genome editing Flashcards
What is genome editing?
A type of genetic engineering in which DNA is inserted, deleted or replaced in the genome of a living organism using engineered nucleases.
What do nucleases do?
Cut the DNA double helix at a particular recognition sequence. The cut can be repaired in a way that introduces mutations.
How is genome editing used in drug development?
Allows target validation; helps confirm a molecule is going to be a good drug target. Gene KO replicates what a drug would do.
How is genome editing used in animal models?
Introduce a mutation thought to be associated with a disease and observe whether the disease phenotype occurs in the animal.
How is genome editing used in the food industry?
Making crops resistant to pathogens or with increased yields.
What is gene surgery?
Using genome editing in cells from patients to correct a defect (cells edited in vitro and then injected back into patient, or nucleases injected and act in vivo).
Why is engineering zinc finger proteins (ZFs) difficult?
ZFs bind 3 nucleotide sequences. Design of specific ZFs was hard because binding a string of ZFs on a longer target sequence interfered with the specificity of each ZF. Also it was hard to find a ZF in vitro that behaved how you wanted to base your design off.
Which proteins have been used for gene editing?
1990s - 2012: zinc fingers
2010 - 2014: TAL effectors
2013 onwards: CRISPR
Why was synthesising TAL effector DNA target proteins hard?
Each nucleotide required a separate TAL effector domain for binding, and synthesising all these domains together was complex. No interference though!
Why was CRISPR design so easy?
CRISPR involves RNA sequences recognising DNA sequences, and the interactions between RNA and DNA are well characterised so easy to design.
Got to slide 5, 10 mins in
