Dr. Raghuram Badmi:

We can do it in multiple ways. Basically, the CRISPR-Cas9, which we are talking about, is a pair of scissors. We can tell the CRISPR where to go and bind and it then goes and binds at that specific sequence in the millions of base pairs in the DNA. It goes specifically and binds there and it cuts the DNA. That is what CRISPR basically does. Then the cell recognises that there is a cut in the DNA and it has to repair that, as it cannot be left unrepaired. When the cell tries to repair the DNA, that is when it introduces a different DNA base. Let us say there is a piece of DNA we want to change, when it tries to repair the cut DNA - we call it ligating - by trying to glue the different pieces, the cell itself changes the base from A to C, for example. When it changes from A to C the DNA core is changed. The single letter change out of millions of base pair changes will lead to loss of function of the gene which harbours this changed nuclear type. It stops functioning. What we are trying to do is to stop the gene from functioning by asking the cell to introduce a mistake or perhaps it is not a mistake to the cell.