In my second year, after moving to the Medical School, I began the courses of Anatomy and Physiology. I had begun to see that I was interested in cells and their functions.

I completed the first three years of primary school in one year and was admitted to the local school the age of six directly into the fourth year, some two years younger than all my contemporaries.

I lived at home and I cycled every morning to the railway station to travel by train to Johannesburg followed by a walk to the University, carrying sandwiches for my lunch and returning in the evening the same way.

In my second year, after moving to the Medical School, I began the courses of Anatomy and Physiology. I had begun to see that I was interested in cells and their functions.

So that's when I saw the DNA model for the first time, in the Cavendish, and that's when I saw that this was it. And in a flash you just knew that this was very fundamental.

I set up a laboratory in the Department of Physiology in the Medical School in South Africa and begin to try to find a bacteriophage system which we might use to solve the genetic code.

It is now widely realized that nearly all the 'classical' problems of molecular biology have either been solved or will be solved in the next decade. The entry of large numbers of American and other biochemists into the field will ensure that all the chemical details of replication and transcription will be elucidated. Because of this, I have long felt that the future of molecular biology lies in the extension of research to other fields of biology, notably development and the nervous system.