Science visions, dark and bright

Talk about change was more plentiful in 2008 than loose coins in an old couch.

Despite all the lip-flapping, that place where gods and devils dwell -- the details -- was largely unexplored.

The Obama administration will soon offer its ideas for reviving the economy and reshaping America's foreign policy. But politicians aren't the only ones who can remake the world.

Scientists have at least as much power to transform our lives and history. What "game-changing scientific ideas and developments" do they expect to occur during the next few decades?

That's the question John Brockman, editor of the Web site edge.org, posed to about 160 cutting-edge minds in his 11th annual Edge Question. As in years past, they responded with bold, often thrilling, sometimes chilling, answers.

Some see the dawning of a new era in which machines replace most human labor and we kick our addiction to oil with the help of the mighty sun and hungry microorganisms. Others envision us colonizing distant galaxies, developing immensely powerful quantum computers and redefining the notion of empathy as being able to know how birds feel when they are soaring across the sky.

A few offer darker forecasts, of a world crippled by nuclear weapons and our unwillingness to act forcefully on global climate change.

Echoing the 2008 political campaign, hope was far more prevalent than gloom among Brockman's respondents. While detailing an array of ideas, the greatest number of responses focused on medical breakthroughs that may allow us to live 150 years or more, replace broken body parts like flat tires and tap the full potential of our minds.

Those prospects seem probable because they are based on two current lines of research: those involving stem cells and the human genome.

A key to longevity could be found in the first days after conception, when we were all cute little fertilized eggs whose few cells (aka stem cells) had limitless possibilities -- they might become any part of our bodies. That's exactly what they do as cell division continues and some form lungs, others hearts, arms or legs.

By working with these undifferentiated stem cells, researchers have grown mouse hearts and pig bladders, reports Juan Enriquez, founding director of the Harvard Business School's Life Science Project. Other scientists have transformed adult skin cells into stem cells, providing, perhaps, a limitless supply of them while avoiding the politics that surround abortion.

While discussion of stem cells centers on their use in combating disease, Enriquez said healthy people may turn to them for enhancement. Just as some lizards and crabs can regrow limbs, humans may be able to regenerate entire arms, legs and organs that are better than those provided us at birth.

"Many of our grandchildren," Enriquez writes, "will likely engineer themselves into what we would consider a new species, one with extraordinary capabilities."

The unlocking of the human genome will make medicine radically more effective. Today it costs about $350,000 to sequence an individual's genome; a few years ago, it cost $1 billion. Further price drops will spark an era of "personalized medicine in which drugs are prescribed according to the patient's molecular background rather than by trial and error," writes Steven Pinker, a psychology professor at Harvard University.

It will also eliminate many genetic diseases.

"Just as Tay-Sachs has almost been wiped out in the decade since Ashkenazi Jews have tested themselves for the gene," he writes, "a universal carrier screen ... [may] eliminate hundreds of other" disorders."