Scientists may have found a new way of obtaining stem cells from human embryos that would help ease ethical controversy over the process.

Researchers collaborating at several universities nationwide have shown that stem cells obtained from an unfertilized monkey egg are nearly the same as the fertilized stem cells that researchers are currently using. Their findings appear in the Sept. 22 issue of the online Proceedings of the National Academy of Sciences.

Because they have the capacity to develop into any type of cell in the body, embryonic stem cells are currently researched for their therapeutic applications to a variety of different diseases, such as Parkinson’s and Alzheimer’s.

There are an estimated 11 existing embryonic stem-cell lines in the world, but federal law prohibits the production of any new lines because of ethical concerns. The current procedure for obtaining stem cells requires several days for growth of a fertilized embryo, which is often viewed as a controversial practice.

The new procedure, known as parthenogenesis, or the process in which an egg is triggered to develop into an embryo without the aid of a sperm, may be less controversial because the stem cells are obtained without creating or destroying a viable embryo.

“This research is very exciting. If this process (of parthenogenesis) can occur in humans, it probably eliminates all of the ethical concerns of current stem-cell research,” University of Wisconsin professor of Human Oncology Steven Clark said.

Some view this new process as much more ethical because there is no way a researcher can get an unfertilized embryo to grow into an animal, Clark said.

Parthenogenesis is a common mode of reproduction in lower animals, such as insects or lizards, so accomplishing this reproductive technology among primates is very interesting, Clark said.

Still others believe an embryo is an embryo, and that using parthenotes, or stem cells created from the “single-parent” embryos, is just as unethical as using the current embryonic stem cells.

“All of life is sacred, from conception to natural death. Stem-cell research is deciding which is to live and which is to die. This is playing God, and this is dangerous,” said Randy Timmerman, pastor of St. Paul’s University Catholic Center.

Although this research has only been performed in monkeys so far, the process has potential to work in humans. The current procedure for obtaining stem cells was first discovered in primates and this knowledge eventually led to the same procedure in humans.

“Once something like this has been done in primates, one must wonder if it can be done in [human primates] too,” UW law and medical-ethics professor R. Alta Charo said.

The parthenotes have been coaxed into mature cells such as muscle, nerve and heart cells, and they have been shown to survive indefinitely.

Cells from the unfertilized monkey egg have not yet been transplanted back to the monkey donor, so researchers are not entirely sure whether the animal will accept or reject the cells.

There is some concern that the DNA is not entirely the same as the donor’s because of genetic recombination, so further research is needed before researchers try this in humans.

If this research does lead to the production of stem cells in humans, therapeutic aid can only be applied to a distinct group of people, such as fertile females.

The process would not benefit men or post-menopausal women.