We don’t want to sound alarmist, and are not saying that CRISPR-Cas9 is bad or dangerous. This is clearly going to be a major tool for use in medicine, so it’s important to pay attention to potential safety concerns
- Jussi Taipale
The team, led by Professor Jussi Taipale, now at the Department of Biochemistry, Cambridge, found that CRISPR-Cas9 triggers a mechanism designed to protect cells from DNA damage, making gene editing more difficult. Cells which lack this mechanism are easier to edit than normal cells. This can lead to a situation where genome-edited cell populations have increased numbers of cells in which an important mechanism protecting cells against DNA damage is missing.
Discovered in bacteria, the CRISPR-Cas9 system is part of the armoury that bacteria use to protect themselves from the harmful effects of viruses. Today it is being co-opted by scientists worldwide as a way of removing and replacing gene defects.
One part of the CRISPR-Cas9 system acts like a GPS locator that can be programmed to go to an exact place in the genome. The other part – the ‘molecular scissors’ – cuts both strands of the faulty DNA so that it can be replaced with DNA that does not have the defect.
However, in a study published today in the journal Nature Medicine, researchers found unexpected consequences from using CRISPR-Cas9.
Image: Scissors cut metal
Credit: ulleo
Reproduced courtesy of the University of Cambridge