It looks like the work they were given supports the cas9 issue you were mentioning:
> Several scientists reviewed materials that He provided to the AP and said tests so far are insufficient to say the editing worked or to rule out harm.
> They also noted evidence that the editing was incomplete and that at least one twin appears to be a patchwork of cells with various changes.
> Several scientists reviewed materials that He provided to the AP and said tests so far are insufficient to say the editing worked or to rule out harm.
> They also noted evidence that the editing was incomplete and that at least one twin appears to be a patchwork of cells with various changes.