I was a close observer of the developments in molecular biology.

From an early age I was told that I was expected to do more than continue to run a small business. Education was important and seen as a way of moving forward.

I had changed from being a mathematician to a practicing scientist. I was increasingly embarassed that I could no longer follow some of the more modern branches of pure mathematics.

I am delighted to have had students, friends and colleagues in so many nations and to have learned so much of what I know from them. This Nobel Award honours them all.

Our children were mostly brought up and educated in the Churchill suburb east of Pittsburgh. Each summer, we took them back to England for an extended period.

I have had many opportunities to visit universities all over the world in the past 50 years.

I was a close observer of the developments in molecular biology.