Mankind's increasing understanding of the way genes influence behavior and the issue's potential to cause ethical and moral dilemmas is one of the biggest dangers facing society, according to leading scientists. The concerns were voiced as part of an exercise by the Web site magazine Edge, which asked more than 100 scientists and philosophers: "What is your dangerous idea?"
The responses were published online recently.
Craig Venter, founder of the J Craig Venter Science Foundation, said the genetic basis of personality and behavior would cause conflicts in society. He said it was inevitable that strong genetic components would be discovered at the root of many more human characteristics such as personality type, language capability, intelligence, quality of memory and athletic ability.
"The danger rests with what we already know: that we are not all created equal," he said.
It is an idea echoed by Steven Pinker, a psychologist at Harvard University.
"The human genomic revolution has spawned an enormous amount of commentary about the possible perils of cloning and human genetic enhancement. I suspect that these are red herrings. When people realize that cloning is just forgoing a genetically mixed child for a twin of one parent, and is not the resurrection of the soul or a source of replacement organs, no one will want to do it," he said.
"Likewise, when they realize that most genes have costs as well as benefits [they may raise a child's IQ but also predispose him to genetic disease], `designer babies' will lose whatever appeal they have," he added.
Richard Dawkins, of Oxford University, said our increased understanding of how our brains work would lead to difficult questions in defining morality.
"As scientists, we believe that human brains, though they may not work in the same way as man-made computers, are as surely governed by the laws of physics," Dawkins said.
"When a computer malfunctions, we do not punish it. We track down the problem and fix it, usually by replacing a damaged component, either in hardware or software. Isn't the murderer or the rapist just a machine with a defective component? Or a defective upbringing? Defective education? Defective genes?" he said.
Other scientists chose to focus on people's relationship with the environment. Physicist Paul Davies puts forward the idea that our fight against global warming may be lost.
"The idea of giving up the global warming struggle is dangerous because it shouldn't have come to this. Mankind does have the resources and the technology to cut greenhouse gas emissions. What we lack is the political will." he said.
Samuel Barondes, a neurobiologist at the University of California, San Francisco, is concerned at the march of drugs that can control the behavior of the brain.
Medications such as Prozac have been used successfully for years to treat conditions from depression to more serious psychiatric illnesses.
"Despite the testimonials and apparent successes, the sustained use of such drugs to change personality should still be considered dangerous," Barondes said.
"The real danger is that there are no controlled studies of the effects of these drugs on personality over the many years or even decades in which some people are taking them," he added.
The president of UK science group Royal Society, Martin Rees, said the most dangerous idea was public concern that science and technology were running out of control.
"Almost any scientific discovery has a potential for evil as well as for good. Its applications can be channelled either way, depending on our personal and political choices.
We can't accept the benefits without also confronting the risks. The decisions that we make, individually and collectively, will determine whether the outcomes of 21st century sciences are benign or devastating," Rees said.
Rees argues that the feeling of fatalism will get in the way of properly regulating how science progresses.
The future will best be safeguarded by people who are not too fatalistic, he said.