Crispr-Cas9 explained: the biggest revolution in gene editing

Are designer babies with enhanced intelligence or strength just around the corner? The simple answer is no. The technology that makes this important conversation possible is called CRISPR.

A revolutionary gene-editing tool that allows scientists to make precise changes to the DNA in any cell or organism. So fairly early on in the development of the CRISPR technology, I had a dream in which a scientist was introducing me to a man in a dark room and when that man turned around it was Adolf Hitler asking me to describe to him how the CRISPR technology worked and tell him how it could be useful. And I woke up from that dream with a real start and that was one of the things that motivated me to begin discussing publicly the implications.

The same time over the last few years, I've come to feel that the greatest problem may be fear itself. I think that it's very important to understand that the CRISPR technology has the potential to do many beneficial things for society and to reject that technology because we are uncertain about the way it may be used in the future, I think would be a mistake. The CRISPR technology is based on a bacterial immune system that allows bacteria to fight viral infection.

How do they do this? They actually use a programmable enzyme called caste 9 that can be programmed with little bits of RNA, these are little copies of DNA sequences that allow the caste 9 protein to find a piece of DNA inside of a cell and cut it and when that cleavage occurs in the DNA, cells take over, repair the break and in the process introduce a change to the DNA precisely at that place in the genome. One of the reasons scientists are so excited about the CRISPR technology is that it can be used to correct mutations that cause genetic disease like cystic fibrosis or Duchenne muscular dystrophy.

Gene editing can also be used in the germline that means in eggs or sperm or embryos and when changes are made to DNA in those cells, the trait can be passed on to all of their future descendants. So, it gives us now the power to change the very nature of what makes us human. In reality, it's not going to be possible to design a human being.

We're too complicated and there are too many unknowns about the human genome. But I do think that in the not-distant future, we will correct disease-causing mutations. Given that this future for humankind is near, how do we prepare for it?

Here are a few of the most important questions that we all need to debate. Number one, safety. We need to ensure the safety of gene editing, especially if it were to be used in human embryos.

Number two, prioritisation. We should limit the use of CRISPR-based gene editing in embryos to cases where there's no alternative. Number three, access.

This technology should not only be available to the wealthy, it should be available to everyone and how do we ensure that that happens? I think that's a very important discussion to be having right now. Number four, engagement.

It's incredibly important that citizens everywhere have a voice in deciding how to use powerful technologies like CRISPR. It's important to understand that CRISPR gene editing is useful in many areas of biology and technology. I'm most excited right now about the ability to generate plants that are resistant to climate change, then perhaps have better nutritional value.

It has value has huge implications for human health globally and I think that's one of the areas where the CRISPR technology may have the most immediate impact.