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Scientists should proceed cautiously before tinkering with human genome

Science has no morality. It just is. Discovery leads to discovery leads to discovery. It is futile and even undesirable to try to hold it back. All we can do is try to channel it, control it and encourage its ethical use.

That is the problem and the promise of a newly developed technique of genome editing, a process that can not only alter the characteristics of an individual, but can conjure inheritable changes that will be passed from generation to generation. It’s a promising and powerful advance, and a frightening one, too.

That’s why it is not only wise, but essential, that one of the creators of the new editing technique, Jennifer A. Doudna of the University of California, Berkeley, has called for controls over the technique. Indeed, a group of leading biologists has called for a worldwide moratorium on applying the technique to humans.

The potential uses are nothing short of mind-boggling. With this technique, which is relatively easy to employ – though not infallible – it would be possible to control human heredity. A family beset by cancers generation after generation could free its descendants of that curse. Or big noses could be banished.

The problem is that no one knows what the long-term consequences of such God-like tinkering could be. Would it be without unintended consequence? Maybe, but it would surely be the first scientific advance never to have one.

“We worry about people making changes without the knowledge of what those changes mean in terms of the overall genome,” said David Baltimore, a former president of the California Institute of Technology. “I personally think we are just not smart enough – and won’t be for a very long time – to feel comfortable about the consequences of changing heredity, even in a single individual.”

It’s a critical point, one over which governments in the United States and Europe already exert some control. But the scientists advocating a moratorium are worried about countries where regulations on the use of science are less stringent.

And also, the technique is not perfect. Although the new procedure is efficient, it sometimes cuts the genome at unintended sites. The consequences can be fatal, and there is no agreement on the question of how much mistargeting should be tolerated. That is among the issues that Doudna and her group want to see thoroughly examined.

The good news is that there is a history of scientists refraining, when asked, from employing new techniques. But humankind also has a history of scientific experimentation that lacked any inkling of ethical restraint. It will hardly be surprising if somebody, somewhere, begins prematurely toying with inheritable human genomes. In fact, given the predilections of human nature, it would be surprising if that didn’t happen. Call it the Kevorkian Effect.

That is why it is urgent for governments to act as restraints, not on the development of science but on its application, especially to humans and especially when the science offers – or threatens – to permanently alter the course of a particular bloodline.

The ability to edit genomes no doubt holds tremendous potential for mankind. But the more humans are able to tinker with the essence of life, the greater the risks for error, and perhaps catastrophic errors. The potential here is both too great to ignore and too terrible to proceed with anything less than deliberative caution.