I read this article https://www.quantamagazine.org/20150206-crispr-dna-editor-bacteria/ and am slightly puzzled as to why the CRISPR/Cas 9 system is seen as being so revolutionary. It seems like the very same thing that micro RNA and short interfering RNA does- cleaves synthesised mRNA strands by attaching to the complementary part of the mmRNA strand, and the restrictive enzymes combine to this RNA and cleave it. I don't see how the CRISPR system is any different or better...
Thank you in advance :)
EDIT: Also, does anyone know whether Cas 9 cuts both DNA strands at the same place, or whether it leaves 'sticky ends'? Thank you.