> Despite claims by scientists and pharma companies there is little chance CRISPR will ever be widely used in the clinic to directly treat disease. That is because it suffers from all the same faults as its predecessors and maybe even more so. Gene editing has low efficiency in adult animals(yes humans are animals) no matter the technique used. For instance, if you have a disease that affects the brain you can probably only modify <1% of cells even using the best delivery techniques available. Really, the only way to get rid of genetically inherited diseases using gene editing is by modifying embryos.
> Misleading as it has been CRISPR can’t actually make specific changes to a gene easily in an adult animal. That is because it requires what is called a donor template, basically just a DNA template that cells can use to create the genome modifications. There is no efficient way to use donor templates in an adult animal so all genome edits would need to be gene knock-outs only i.e. you can only use CRISPR to destroy bad genes not modify them to make them good genes. As you can imagine this is very limited in scope when it comes to diseases that can and should be reasonably targeted using genome editing.