Francis Collins

The brain is the most complicated organ in the universe. We have learned a lot about other human organs. We know how the heart pumps and how the kidney does what it does. To a certain degree, we have read the letters of the human genome. But the brain has 100 billion neurons. Each one of those has about 10,000 connections.

A cardinal principle that we must not stray from - no exceptions - is that your genetic information is your business in terms of who sees it. Nobody should be gaining access to that information without your explicit permission, and nobody should be requiring you to take a genetic test unless you decide that that's what you want to do.

Genes are effectively one-dimensional. If you write down the sequence of A, C, G and T, that's kind of what you need to know about that gene. But proteins are three-dimensional. They have to be because we are three-dimensional, and we're made of those proteins. Otherwise we'd all sort of be linear, unimaginably weird creatures.

It is only when you watch the dense mass of thousands of ants, crowded together around the Hill, blackening the ground, that you begin to see the whole beast, and now you observe it thinking, planning, calculating. It is an intelligence, a kind of live computer, with crawling bits for its wits.

It's terrifying the way molecular biology has become more and more jargon ridden. But I strongly believe that my book can be read by the intelligent layman. I want everyone who bought a copy of 'A Brief History of Time' to buy a copy of 'Genome'.