Many humans are immune to Cas9 that is used for gene therapy
Our immune cells attack Cas9 that is used for gene therapy - health science news

CRISPR-Cas9 is a new molecular gene editing technique that is used to make specific changes in the DNA of animals and plants, and could also be used in humans. However, scientists found that most of us have immunity to Cas9, so that the technique cannot be used safely in humans in its current form. Immunity is caused by infections of Streptococcus bacteria, from which Cas9 is derived. Thus, new solutions have to be found to prevent dangerous immunological reactions before CRISPR-Cas9 can be used safely in humans.

Read the full story: Charité Berlin
Scientific publication: Nature Medicine