John Gurdon

I think that I cannot immediately see the route by which we should really understand memory and the workings of the brain.

There's a danger of some of the best people saying, 'I don't want a career in science.'

The aim of a nuclear-transplant experiment is to insert the nucleus of a specialized cell into an unfertilized egg whose nucleus has been removed.

I have this rather amazing report which, roughly speaking, says I was the worst student the biology master had ever taught.

The earliest example known to me of replaced body parts is exemplified by a Mayan skull dating back to 1400 BC. In this skull, false teeth made of stone had been implanted.

For my part, I have worked all my life with eggs and embryos of frogs. Compared to other small animals, these have figured prominently in the world of literature.

As with most animal eggs, the early events of amphibian development are largely independent of the environment, and the processes leading to cell differentiation must involve a redistribution and interaction of constituents already present in the fertilized egg.

I take the view that anything you can do to relieve suffering or improve human health will usually be widely accepted by the public - that is to say, if cloning actually turned out to be solving some problems and was useful to people, I think it would be accepted.

It is particularly pleasing to see how purely basic research, originally aimed at testing the genetic identity of different cell types in the body, has turned out to have clear human health prospects.

The first point to remember is that attempts to clone mice have actually been very unsuccessful for at least a decade. Sheep have been successful. So one asks, 'Where do humans lie?' Most people think they are somewhere between the two, but at least there's a reasonable chance they might be clone-able.

The importance of the egg's non-nuclear material - the cytoplasm - in early development is apparent in the consistent relation that is seen to exist between certain regions in the cytoplasm of a fertilized egg and certain kinds or directions of cell differentiation.

I remember that, at an early age, I spent many months making a three-masted sailing boat with rigging in a half-walnut shell.