The acronym stands for 'Clustered Regularly Inter-Spaced Palindromic Repeats'.
The technique involves a DNA cutting enzyme and a small tag which tells the enzyme where to cut.
Together, these genetic editors give scientists the remarkable ability to rewrite any mutated base pair in the genome.
CRISPR-Cas9 is a tool for making precise edits in DNA, discovered in bacteria.
CRISPR works but making cuts in the genome, and Dr Zheng's latest technique, REPAIR is essentially the same thing, but for RNA.
RNA editing avoids interfering with the genome itself.
While healthy people cough naturally, that does not happen for people with CF.
But, the simplicity of the system means that one wrong letter can throw off important parts of us.
ABE targets the ‘A,’ adenine, and rearranges its atoms to turn it into guanine.
Adenine is always paired with thymine, and guanine is always paired with cytosine.
The order and repetitions of three billion of these pairs – AT and GC – throughout the genome code for everything about us.