JB: Speaking of cells, let's jump off this track for a minute and talk about the cloning experiment in Scotland. People are having a hard time getting their heads around it.

MADDOX: I look at the scientific importance of that experiment in the following way: it seems to me is that it is a demonstration that you can take an ordinary cell from a person's body, a somatic cell as it's called, and recreate the genome from that. The reason that's interesting and important is that up until now people haven't been sure whether the DNA in every cell of our body retains the power of making an embryo. This experiment shows that that happens. You can in principle take a cell from your skin or anywhere and make it into an embryo which then grows up into a person. That rules out a number of possibilities for the ways in which different tissues of our body have their different characteristics. Now a liver cell and a kidney cell are outwardly very different; a skin cell and a nerve cell are very different to look at, in their properties, and their behavior. But in practice, the difference could be because their genes have been changed in some way. This experiment in Scotland shows their genes have not been changed radically. They've been silenced, perhaps, but only temporarily. That's very important.

Now as to the practical importance, it seems to me that the immediate value of it is in animal husbandry, and that is in those fields where people have been trying to use sheep, or pigs, or cows, to generate biochemicals - to make medicines in sheep. There's a lot of interest in this. The procedure is quite simple: you introduce the human gene responsible shall we say for making insulin, into sheep, and then you collect the insulin from the sheep, and you find it's human insulin, not sheep insulin. Thus you have natural human medicine generated on a farm.

This kind of work is very difficult, because it's very much a matter of chance to where the human insulin gene will go. If you can take a successful chance, a case where the gene has gone in the right place and it's producing in the sheep a lot of insulin, then you can clone that sheep and get many many other sheep. You don't have to rely on chance any more. So that's going to be the immediate practical value.

The dangerous question is what happens when people start doing it to themselves - to people. For what it's worth, in Britain and many other countries, it's against the law to do this; it's a criminal offense to manipulate the human embryo beyond 14 days of life, and it's in fact a criminal offense to do so without the approval of a licensing authority. How effective that interdiction would be in other countries is anybody's guess. My guess is that countries like Morocco, which has been in the vanguard of sex change operations for many, many years will be in the vanguard of people cloning. So in that spirit, it's a question of waiting to see how the technology works out, and trying to get some kind of international understanding on the circumstances where it would make a lot of sense.

Are there any circumstances in which it would make a lot of sense? I can think of one. Coming back to one of the other questions I mentioned at the beginning, suppose we got into a situation where we had reason to believe that there was something wrong, something inherently wrong, with a set of genes that people have inherited, which have been evolved, of course, over the past four and a half million years, since we separated from the great apes. Suppose that we had reason to believe that one of those genes was going to cause trouble as time went on. For example, there is a case which one shouldn't make too much of, but's it's an illustrative case, of Huntington's disease, where there's a normal gene in every one of us, which makes a protein called huntington - nobody knows what its function is. This gene - this gene at cell division, when people procreate, produces a bit of nonsense at the end, and if the bit of nonsense is longer than a certain amount, it actually gives a person Huntington's disease - and he or she dies. That's bad news. There are half a dozen other diseases like that, same unbalanced mechanism. If there were a lot of those incidences, you could pretty well say that the time will come in the evolution of people when we'll all be dying of Huntington's. One way of avoiding it would be to clone people who didn't have this propensity. That's about the only circumstance in which I can see people cloning, as the last resort for the human race to avoid a calamity that would be brought about by gross instability of the human genome. I'm not saying that this is a real prospect now, but maybe in a hundred generations it could be.

JB: What other areas are causes of concern to you?

MADDOX: I've got a very simple view about the environmental problem that we all know about which is that a great deal of the excitement there's been in the past 25 years about the environment can be boiled down to this: one can say look, you can get whatever environment you wish, provided you are prepared to pay for it. You can get air as clean as you like, water as clean as you like provided that taxes, and the regulation of the private sector is tight enough to meet the standards laid down. This does mean, of course, that the countries that can afford a clean environment are the rich countries, and the environment they purchase is a big purchase - sometimes out of public funds, sometimes out of private funds. Poor countries can't afford a decent environment, but as they get rich they will enjoy the wealth necessary to make them see that a clean environment is good for them.

The real environment problems now, it seems to me, are things like infection. We've had AIDS pop up since the early 1980's; it's been a big shock to people that there could be such a completely novel disease doing such terrible damage and apparently untreatable by existing remedies. It's my belief that there must be many other diseases like this waiting for us as the centuries tick by. Suppose, for example, that there were a really infectious cancer virus, something which could just give you lung cancer if you took it in as if it were flu. There's only one known human cancer virus at present, but there are many in the cases of domestic animals like cats, such as the leukemia virus that's well known. The only human cancer known is papilloma virus which causes cervical cancer. And we all know that quite apart from these bizarre novel viruses, there are ordinary bacteria, like E. Coli, that from time to time acquire mutations that make them more virulent. The new E. Coli strain 170, for example, has caused a lot of damage in the United States, in Japan, and now in Britain. Dozens of people have died of food poisoning, in effect.

These bacteria are going to become more and more common as the years go by because we are putting the bacteria under such enormous pressure with the intelligent use of antibiotics in hospitals, curing the sick, and so on, the bacteria really have nowhere to go unless they become more virulent.

So we must expect that however good the defenses are - by defenses I mean the drugs, the hygiene - the bacteria are going to keep on getting more virulent unless they can be really hit hard. We have the prospect ahead of us of increasing threats from viruses and bacteria, and the organisms that cause diseases like malaria. It's actually part of the price we pay for living longer, for being healthier. It's just one of those things, something that one ought to reckon with, not wring one's hands about.

There's another worry, one which perhaps sounds unreasonable. I believe that it's only a matter of time before the world will have to plan to avoid catastrophe by the impact of asteroids. It's now known that 64 million years ago the Cretaceous Period and the dinosaurs were brought to an end because there was a big impact of an asteroid ten kilometers across - about six miles across - the impact site has been found on the Caribbean coast of Mexico, and the crater it left in the ground is 180 kilometers - about 110 miles across. It put up dust into the atmosphere, and the dust stayed there for so long that the vegetation died off, and the dinosaurs that ate grass died off with it, and lots of other species as well. That kind of event is likely to recur every few tens of millions of years.

Luckily, the techniques are good enough to be able to pick up about 90% of the objects that size in the neighborhood of the earth. They're called asteroids, or they may be comets. The biggest difficulty is that of a cometary impact because comets travel at a faster speed than asteroids and the warning would be less. But if you think that the whole world was put to an end 64 million years ago pretty well, by one impact, is it not sensible that the human race should do something to protect its own stake in the future? I believe we should be planning to do something about events like that that might happen in the future. Of course smaller impacts can do a lot of damage too. I think it's only a matter of time before people will be setting out to track those things, and to destroy them.