Extraordinary research that shows promise in altering mammalian DNA more efficiently than CRISPR-Cas9, but after multiple attempts, no one can recreate the experiment? What gives? There is a lot of speculation, but mostly complaints as to why researchers failed to replicate it.
There have been many controversial reports as to what the possible role of NgAgo is, but none of them involve editing of genes. One theory was that NgAgo was thought to clamp onto a gene and limit it's expression, noted in the experiment on eye development in zebrafish, but this were correct, the enzyme would not permanently change gene function that's passed down every generation.
Another theory was that temperature could play a key aspect to a successful experiment. The original experiment was carried out in a cool environment, which allows the bacteria, that makes the protein, lives.
Whether this protein's role is entirely different than what the original report says it is, needs to be kept in a cool environment, or just simply doesn't work, the debate surrounding this experiment is insane. Until the NgAgo experiment is published, we will never know whether this enzyme is used for gene editing.