h+ Magazine

Fall 2008

Issue link: http://cp.revolio.com/i/393

Contents of this Issue

Navigation

Page 11 of 41

12 #1 Fall 2008 Bio Simple Questions/ Challenging Answers Moira A. Gunn, Ph.D. Is the product of a cloned cow, cloned milk? Or real milk? Is the offspring of a cloned cow and a "natural" bull, a half-clone? And then when they mix again, as cows and bulls of all persuasions are apt to do, do we get quarter-clones? ree-quarter clones? e parlor game must obviously stop in a very few generations, but the melody lingers on. Like genetically modified seeds that have jumped the fence and are mixing and matching in the wild, once the progression begins, it's a little hard to follow. So now let's look at some interesting challenges that emerge on the human scale. In the United States, women are free to pursue in vitro fertilization, and American clinics have really gotten good at it. When they treat young women – who might be motivated because they are about to undergo chemotherapy or other medical procedures that might compromise fertility – it is not unusual for a woman to emerge with a dozen or more viable eggs. Today we know better than to implant more than two at any one attempt, and so we find our- selves with hundreds of thousands of fer- tilized eggs on ice. No one knows exactly how many, because while the federal gov- ernment will only permit federal research funds to be expended on the stem cell lines derived as of August 9, 2001, when Presi- dent George W. Bush issued his Executive Order, the government does not regulate this particular end of the techno-human reproductive supply chain. Not so with the Brits. I have just re- turned from the international BIO confer- ence, where I had the great good fortune to moderate a panel of fellows including the illustrious Dr. Lyle Armstrong, who heads the Institute for Human Genetics at Newcastle University. With the recent pas- sage of an update to the UK Human Fer- tilisation and Embryology Act of 1990, his group has now proceeded on to something rather controversial. Under the original act, the government had regulatory control over private citizens' frozen embryos, which re- quired that they be tracked and that each private citizen make a decision about these "frozen potentials" within a reasonable time frame. No frozen potential went unnoticed. But that's not the story. Despite the absolute tracking of each and every embryo, the UK permits stem cell research on any viable line. is is where Dr. Armstrong and the latest revision of the act enter the picture. And wouldn't you know it? So do the cows. It turns out that the UK researchers can get only a few human eggs each week, while he – or rather his lab – can get per- haps 200 per day from local cows. To quote: "We have a lot of cows." And here… it gets interesting. Under the new approvals, researchers may now take an animal cell, remove its nucleus, and inject it with a nucleus ex- tracted from a human cell. is suits Dr. Armstrong just fine. He and his fellow sci- entists can then proceed to study how early cells develop. e law determines that these cells may not be permitted to live beyond fourteen days, although Dr. Armstrong tells us that they seldom live half that long in any event. Still, in that short time, these cow-cell -- human-nucleus hybrids give scientists a direct way to study cell differen- tiation at its earliest stages. To date, Dr. Armstrong's group has cre- ated 271 human–animal hybrid embryos. By his estimation, they are 99.9% human, 0.1% cow. So where does that leave us? I asked Armstrong directly if we could FedEx him our extras to save him the involvement of the cow, and he very specifically indicated that after eighteen-vplus hours, the human eggs were no longer of use. And yes, if we found another way for him to do the re- search, he would. Expediency. Cows. Humans. e inexo- rable call of science. And there are a whole number of people who find this entire con- versation simultaneously wonderful and Researchers may now take an animal (cow) cell, remove its nucleus, and inject it with a nucleus extracted from a human cell.

Articles in this issue

Archives of this issue

view archives of h+ Magazine - Fall 2008