Genome editing, or genome editing with engineered nucleases (GEEN)

■ It is a type of genetic engineering in which DNA is inserted, deleted or replaced in the genome of a living organism using engineered nucleases, or “molecular scissors.”

■ These nucleases create site-specific double-strand breaks (DSBs) at desired locations in the genome.

■ The induced double-strand breaks are repaired through nonhomologous end-joining (NHEJ) or homologous recombination (HR), resulting in targeted mutations (‘edits’).

■ Four families of engineered nucleases being used:
A) meganucleases,

:sunglasses: zinc finger nucleases (ZFNs)

C) transcription activator-like effector-based nucleases (TALEN), and

D) #Clustered_regularly_interspaced_short_palindromic_repeats (CRISPR)-Cas system.