robert krulwich: one of the most controversialscience stories of the year involves stem cells, cells that may one day cure terriblediseases. but the problem with stem cells is they often come from embryos, thus thephrase "embryonic stem cells." and embryos, while they start no bigger than a grain ofsand, can become babies, so there is a moral issue here. but what ifã³and we're just going to thinkout loudã³what if you could make an embryonic stem cell without creating an embryo? couldyou? should you? well, we know someone who's trying. reporter julia cort has the story. julia cort (correspondent): as he winds throughthe labs of m.i.t., alex meissner is trying
to sidestep an ethical minefield. he hopesthe tiny cells that float in his petri dish might hold the key to solving one of the biggestcontroversies facing science: whether it's ethical to use cells from human embryos inmedical research. rudolf jaenisch: i believe this research hasenormous potential. and it will revolutionize medicine in the years to come. thomas berg: i don't want to live in a world,i don't think anyone wants to live in a world, where we're destroying embryos...we're creatingthem and destroying them in mass quantities for research purposes. julia cort: while experts debated here, halfwayaround the world, south korea seemed to be
forging ahead. last august, they claimed aspectacular first, a cloned dog. but since then, the korean king of clones,hwang woo-suk, has been dethroned, accused of fabricating his results, including groundbreakingwork cloning human embryonic stem cells. the korean fiasco has cast a cloud over the field,but u.s. researchers still want to move forward, believing embryonic stem cells hold greatpotential for medicine, since they can become any kind of cell in the human body. but becausethey come from early human embryos, funding for the research is extremely limited. george daley (harvard stem cell institute):unfortunately, here in the united states, even though we're chomping at the bit to dothe work, the kind of funding restrictions
that we're under, the kind of presidentialpolicy that we're under, is really the hindrance. julia cort: physician and researcher georgedaley is eager to create stem cells that are an exact match to sick patients. to do that,he wants to try cloning technology, but so far, the only cloned cells he's made belongto mice. george daley: we're essentially frozen intime, at 2001, while the rest of the world has moved forward very, very aggressively. julia cort: the controversial cloning processwould work like this: take an egg from a woman's ovary, remove its genes or dna, then, geta cellã³like a skin cellã³from a patient, and put its dna into the egg. the egg is stimulatedto divide, as if it had been fertilized. after
a few days, the early embryo has 50 to 200cells. the goal is to turn some of these into embryonicstem cells that would be a perfect genetic match to a sick patient. but because the clonedembryo would be destroyed in the process, critics say this research is wrong. with thedestruction of human embryos at the center of the debate, a few scientists approachedthe new year asking if it might be possible to make both sides happy. what if they couldfind a way to create embryonic stem cells without destroying any embryos? william hurlbut (stanford university): i thinkit should be doable. julia cort: physician and ethicist williamhurlbut thinks the solution may lie in tinkering
with the cloning process. william hurlbut: there's a way to get thecells without creating embryos. we just have to have the constructive conversation to findthe way. julia cort: the challenge intrigued m.i.t.'srudolf jaenisch, a leading expert on stem cells and cloning. with the help of graduatestudent alex meissner, jaenisch tried to create something that would yield stem cells, butwas not an embryo at all. rudolf jaenisch: what is an embryo? what'simportant? i think an important part of the sense of an embryo is the potential to develop,to organize itself. julia cort: the jaenisch team set out to eliminatethat potential. first, they took a tiny bit
of skin from a mouse's tail and let it growin culture. with the skin cells growing in a petri dish, meissner concocted a specialvirus and added it to the skin cells. the virus went to work and inserted an extra bitof dna into the skin cell dna. meissner performed the cloning, sucking up a skin cell now containingthe extra dna and transferring it into a mouse egg. and then the team waited and watched.jaenisch's hope was that the extra bit of dna they'd added would shut down one key gene,a gene that's crucial for organizing the early mouse embryo and triggering the constructionof the placenta. rudolf jaenisch: the placenta, of course,is very important in signaling the fetus to develop. without the placenta, it cannot.and the experiment worked very straightforward.
it was actually surprisingly simple to us. julia cort: with that key gene turned off,the unorganized cluster of cells did not develop normally, and, jaenisch says, would neverbecome a baby mouse. but it could be turned into useful stem cells. rudolf jaenisch: the real question is, doesit solve the ethical problem? some people said yes, others said, "no. it's a particularlydevious way to murder an embryo." i would argue, from the biological point of view,it is not an embryo. it doesn't qualify to be called this. it doesn't have any potentialwhatsoever to ever organize itself to a fetus. julia cort: father thomas berg is encouragedby jaenisch's experiment.
thomas berg: i think the jury's still outas to whether it's an embryo or not. but i think it's incredibly interesting, from amoral standpoint, from a scientific standpoint, obviously. i think what rudy jaenisch didholds out some hope that those of us who do not want to live with a future of embryo-destructiveresearch, we might have a way out. julia cort: but so far, there is no consensusabout the moral status of what jaenisch created among stem cell opponents or supporters. arthur caplan (university of pennsylvaniaschool of medicine): the scientists who play along, i think, are playing the wrong card.they think, "yeah, maybe if i'm clever enough i'll satisfy all the critics." i think thecritics are not going to be satisfied. i think
they don't want to see embryonic stem cellresearch happen, and i don't think they want to see anything involving cloning happen. julia cort: ethical objections have slowedu.s. research. few labs have tried to use cloning to make human stem cells, and nonehave succeeded. the korean scandal means that the technique for humans is unproven. butthat, for many u.s. researchers, is all the more reason to keep moving ahead. george daley: i have patients, and i can seea way to apply this technology to study their disease and perhaps treat their disease. iwant to be able to use that process today. arthur caplan: if we get diverted into thedebate about, "can we make a pseudo embryo
or an embryo-like thing?," you could spendthe next five, 10 years trying to figure out how to tweak an egg or play with embryos.i think, to spend too much time trying to respond to every possible critic is a recipefor paralysis, not for breakthroughs. robert krulwich: around the corner, aroundthe world, more science stories in the news. hamburg, germany: toads are exploding at analarming rateã³1,000 believed dead. and why? maybe they were bitten and infected by crows,but, says german scientist heidi meyerhofer, "nein!" heidi meyerhofer (translation from german):i have been working here for 15 years and have never experienced a problem this bigwith amphibians. experts could give no advice
about the symptoms. robert krulwich: in short, scientists haven'tthe froggiest idea. meanwhile, back in the u.s.a. ã³if you drive,put down the cell phone because researchers discovered this past year that a normal 30-year-olddriver speaking on a cellular telephone has the reaction time of a 70- or 80-year-old.oh dear! phones and driving prove a deadly mixture. and that's no phony baloney.
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