Dr. Douglas A. Melton, a molecular biologist at HMS, made headlines in 2003 when he announced that he had developed 17 embryonic stem cell lines, which he will make available for research this year.

But since Melton’s batch doesn’t meet the criteria for federal approval, any scientist wanting to use these stem cell lines will need private funding, which is hard to come by.

Even with financial support, experts agree that the ethics of cloning continue to make new projects controversial. Some critics deplore the destruction of embryos for the sake of research, which they equate to abortion.

But Louis M. Guenin, who teaches ethics in science at HMS, contends that experiments with discarded embryos from fertility clinics can lead to important medical treatments.

“It seems difficult to deny that relieving widespread suffering is morally better than destroying embryos at no gain,” Guenin says.

Like discarded embryos from fertility clinics, cloned embryos for research are not meant for implantation in the uterus, says Guenin, addressing concerns that the practice will lead to reproductive cloning.

“[Therapeutic cloning] is an avenue for the humanitarian relief of suffering,” he says.

But despite the benefits, some are still weary.

Dr. Walter Robinson, associate director of the Division of Medical Ethics at Harvard, says that the current regulation could push stem cell research to become commercialized. He says the major emphasis would become “the financial game instead of the open and free exchange of ideas.”

“Ultimately,” Robinson adds, “it becomes a competition on who gets to make the announcement first.”

Despite the continued debate over research, and South Korea’s significant breakthrough, Harvard scientists say they are excited by the progress in the field.

“I was very pumped,” Daley says, recalling his reaction to the news.

“It’s really a small technical breakthrough, one that we’ve done with mammals, but to finally do it with human embryonic stem cells...it’s remarkable.”

—Jackeline Montalvo can be reached at montalvo@fas.harvard.edu.