The journal Nature announced today that scientists using cloning techniques were able to create a line of human stem cells that were derived from early-stage human embryos.
In traditional cloning, an adult egg is used and its one set of chromosomes removed. Then, two sets of chromosomes are inserted into the egg. With technique, the same that created Dolly in 1996, scientists found it nearly impossible to get human cells to divide more than a few times. But, according to Nature, scientists from the New York Stem Cell Foundation Laboratory found that leaving the egg's DNA in tact and inserting the additional two sets of chromosomes produced an embryo that they carried to the blastocyst (70 to 100 cell stage).
This means that the embryos the scientists created had three sets of chromosomes and would never be viable even if implanted in a womb. The stem cells derived from this embryo are also not compatible for uses in curing disease or spinal cord injuries.
The Wall Street Journal reports that this is the closest science has come to cloning humans since 2004:
[...] a Korean scientist who claimed to have created the first human embryonic clone and derived a stem-cell line from it. That work was shown to be fraudulent. While the latest study doesn't claim the same dramatic breakthrough that the 2004 experiment did, it is likely to spark controversy because it involves potential human cloning and embryo destruction.
"It's an early research step… towards curing devastating diseases," said Dieter Egli of the New York Stem Cell Foundation Laboratory in New York City and a co-author of the study, which pointedly doesn't use the word "cloning" to describe the results. "We really don't know how hard it's going to be" to eliminate the extra set of chromosomes.
Scientists continue to try a variety of techniques to remove the egg's DNA and still create a viable embryo. Robert Lanza, chief scientific officer at Advanced Cell Technology, a company based in Santa Monica, California, said to Nature that he believes the problem with removing the egg's chromosomes lies with removal of the spindle apparatus, which is required for cell division:
"Unlike in some other species, these are critical for an embryo to continue to divide. That's the problem, and that's why human cloning hasn't worked to date," he says.
Although the scientists were successful at creating human embryos using cloning techniques, it still is an inefficient process. Only 13 embryos were created from 270 eggs. The Daily Telegraph reports that the eggs used in this study were from women who were paid $8,000, which it notes is close to the same amount egg donors receive from in-vitro clinics.
This study was privately funded.
[h/t Fox News]