Dr Darren Grafham from the Sanger Centre in Hinxton, Cambridgeshire
Part of the show Genetics, DNA Extraction and the Human Genome Project
Chris - What is the importance of sequencing big tracts of DNA?
Darren - Clearly it's important to understand the basics of who we are. It begins with the four letter code, the only four letters of the alphabet that really matter, A, C, T and G. The importance of these is that they're the building blocks for everything we do and everything that makes us. Once we have this, we can build on it to make advances in technology and medicine. Without knowing the genetic code, doing these things is really expensive and time consuming.
Chris - People told us that when we sequenced the human genome we'd have an idea of where all the human genes were. They said that research would be catapulted into the next dimension because we'd understand all about genetic disease. But about 15 years ago, someone published the entire sequence of the herpes simplex virus, that causes cold sores, and it's relative, the chicken pox virus. 90% of the population are still infected with those viruses and they're a major problem. We know the genetic code for them inside-out. So when are we going to see spin-offs from this that are actually going to allow us to cure people?
Darren - It all starts by making a road map, that is the DNA sequence. That gives us a road map but it doesn't tell us who lives in the houses along those streets. Until we know who lives in those houses, or in the case of the herpes simplex virus, what it does and how it interacts with things, we're still pretty lost as to how to stop it and prevent it. So it will take a number of years and some more advances. But once you have a street map, you have a starting point and you can make decisions about where to start looking and begin work.
Chris - Have there been any direct repercussions of the Human Genome Project?
Darren - It's difficult to answer. I think the most recent thing has been a number of cancer drugs that are just coming out and will go into clinical trials in the near future that may have taken another 10 or 15 years to get onto the market. By being able to know the DNA sequence and see the cancerous changes, you can use targeted drugs to actually start to produce medicines.
Chris - So you take the gene and have a look at what the gene makes. The this gives you an idea of what drugs might work against that particular structure.
Darren - That's right. It gives you some idea of what that protein does, including how it's made and how it functions.