Breakthroughs in Stem Cell Research Bring Us One Step Closer to Human Cloning
Several studies published in recent weeks have given researchers hope that obstacles facing stem-cell research may be overcome, as well as renewing concerns regarding the prospect of human cloning.
On April 28, researchers published a study in Nature regarding their creation of the first disease-specific diploid-state human embryonic stem cell for type I diabetes. They added the nuclei from the diabetes sufferer's skin cells to unfertilized donor oocytes in order to create a patient-specific treatment that would give rise to the cells lose in type I diabetes. This reprogramming of a cell into its pluripotent state and allowing it to create beta cells represents a major step towards cell replacement therapies.
Not only did these researchers overcome the obstacle of obtaining ooctyes to use for these studies, but they also made the process more efficient by adding histone deactylase inhibitors, which allowed them to use far fewer oocytes than have previously been used in these experiments.
They also did preliminary analysis of the possible reasons why some eggs are more successful in yielding embryonic stem cells than others: "Those of a little younger age were slightly more efficient that those of a little more advanced age. But I don't think this disqualifies eggs of that older age group entirely. They can work."
On April 17, researchers published their findings in Cell Stem Cell that using caffeine to postpone the cell division process gives scientists more time to reprogram the DNA of the cells before triggering activation. This solved one of the major problems in the cloning process, as previous studies had only given the cells approximately 30 minutes to incubate.
"DNA from terminally differentiated adult cells has to undergo massive genetic changes-it has to be brought back in time to an embryonic state. The two-hour incubation period gave the eggs more time to do this," said co-author of the study Robert Lanza. Using this method, the researchers were able to successfully replace the DNA in embryonic stem cells yielded from donor eggs and stimulate them to begin dividing.
These studies will likely renew interest in somatic cell nuclear transfer (SCNT), the method of cloning used in both of these studies, as opposed to the other method that has been in fashion, induced pluripotent stem cells (iPS), which occurs as a result of direct reprogramming of the cells. SCNT was used to create Dolly the cloned sheep in 1997, a major breakthrough in cloning technology.
But there have been a multitude of problems when attempting to perform the process on human cells, since it required many eggs in order to yield any stem cells at all. There have also been many moral and religious objections, as using human eggs for research can be interpreted as the destruction of human life. Further, the advancements in stem cell research have revived fears of reproductive human cloning. The FDA currently has control over stem cell research, but many want to take it a step further and outright ban human reproductive cloning.
While the benefits of stem cells in the treatment of a myriad of diseases can hardly be disputed, there is also a consciousness of the potential deleterious effects on society if flesh-and-blood human copies were ever created. Many works of literature and film have explored cloning as a dystopic concept, such as Aldous Huxley's "Brave New World" and the film/novel "Never Let Me Go." But the researchers insist that this concern is separate from the purely medical interest in treatments for diseases such as diabetes, and that nearly all professionals are opposed to human cloning.