Post by Bozur on Nov 15, 2005 17:43:24 GMT -5
Scientists' Rift on Stem Cells Surrounded by Mystery
By GINA KOLATA
Published: November 15, 2005
American stem cell experts are baffled by a break between an American researcher and the South Korean research team that has reported producing the first, and so far the only, stem cells derived from cloned human embryos.
The researcher, Gerald P. Schatten of the University of Pittsburgh, announced Saturday that he was suspending his ties with the South Korean team, led by Woo-Suk Hwang of Seoul National University. Dr. Schatten said Dr. Hwang might not have been completely truthful with him in answering questions about possible "ethical violations in the way oocytes were obtained for research." Oocytes are cells from which eggs develop.
The Associated Press quoted Dr. Hwang as saying that he would eventually "divulge everything" and that "all research up until now has been conducted in strict observance of the government-set guidelines." Dr. Hwang did not reply to voice-mail messages or to an e-mail message sent yesterday requesting comment.
In a news release Saturday, Dr. Schatten said he was not questioning the research results. "I continue to believe in the scientific accomplishments of Professor Hwang and his research team at Seoul National University," Dr. Schatten wrote.
At issue is the source of the human eggs the South Koreans used to produce cloned embryos. Sixteen women donated a total of 242 eggs for the experiment, and Dr. Hwang said they were unpaid and had nothing to gain from the experiment. They donated out of altruism, he said.
Dr. Schatten's concerns about how the eggs were obtained led him to suspend his 20-month collaboration with Dr. Hwang's laboratory, he said.
Dr. Schatten has declined requests for interviews, providing only a vague description of the problem in his news release: "The nature of this information mandates confidentiality. I have contacted appropriate academic and regulatory agencies regarding this new information and accordingly, have suspended my collaborations with Professor Hwang."
American stem cell experts said they were in the dark on details of the split.
"I don't know much more" than what was in the news, said Rudolf Jaenisch, a stem cell researcher at the Whitehead Institute in Cambridge, Mass.
They also were reluctant to comment on Dr. Schatten's statement, saying that the questions were serious and that they needed to know more about what had happened.
Dr. Schatten's statement referred to a news article published in the journal Nature in May 2004, two months after Dr. Hwang's group published a paper in Science reporting that they had produced human embryos by cloning and had extracted their stem cells.
The Nature article reported that one of the doctoral students in Dr. Hwang's laboratory said she and another woman there had donated eggs for the experiment. If true, it could be an ethical breach, since the donors were supposed to have no connection to the experiment and no possibility of benefiting from it. As a Ph.D. student, the woman might have felt pressured to donate eggs and might have benefited from it.
The article said, however, that Dr. Hwang had denied that the woman was an egg donor and that the woman then said she had not donated eggs. She said there had been a misunderstanding because her English was poor. Dr. Hwang told a reporter for Science that the woman had tried to say she would like to donate eggs to other research groups, not that she had donated eggs to her own group.
Dr. Schatten said in his news release: "Professor Hwang told me that he had no knowledge of ethical violations in the way oocytes were obtained for his research. Because of my trust in him as a colleague, I believed him." That changed, he wrote, when "information came to my attention suggesting misrepresentations might have occurred."
Human eggs are needed for cloning because they are the only way scientists know to take a specialized adult cell, like a skin cell, and revert it to the state it was in when sperm fertilized egg.
In the United States, ethical guidelines issued by the National Academy of Sciences say that women who donate eggs for embryonic stem cell research must be anonymous and cannot be paid for their eggs.
By GINA KOLATA
Published: November 15, 2005
American stem cell experts are baffled by a break between an American researcher and the South Korean research team that has reported producing the first, and so far the only, stem cells derived from cloned human embryos.
The researcher, Gerald P. Schatten of the University of Pittsburgh, announced Saturday that he was suspending his ties with the South Korean team, led by Woo-Suk Hwang of Seoul National University. Dr. Schatten said Dr. Hwang might not have been completely truthful with him in answering questions about possible "ethical violations in the way oocytes were obtained for research." Oocytes are cells from which eggs develop.
The Associated Press quoted Dr. Hwang as saying that he would eventually "divulge everything" and that "all research up until now has been conducted in strict observance of the government-set guidelines." Dr. Hwang did not reply to voice-mail messages or to an e-mail message sent yesterday requesting comment.
In a news release Saturday, Dr. Schatten said he was not questioning the research results. "I continue to believe in the scientific accomplishments of Professor Hwang and his research team at Seoul National University," Dr. Schatten wrote.
At issue is the source of the human eggs the South Koreans used to produce cloned embryos. Sixteen women donated a total of 242 eggs for the experiment, and Dr. Hwang said they were unpaid and had nothing to gain from the experiment. They donated out of altruism, he said.
Dr. Schatten's concerns about how the eggs were obtained led him to suspend his 20-month collaboration with Dr. Hwang's laboratory, he said.
Dr. Schatten has declined requests for interviews, providing only a vague description of the problem in his news release: "The nature of this information mandates confidentiality. I have contacted appropriate academic and regulatory agencies regarding this new information and accordingly, have suspended my collaborations with Professor Hwang."
American stem cell experts said they were in the dark on details of the split.
"I don't know much more" than what was in the news, said Rudolf Jaenisch, a stem cell researcher at the Whitehead Institute in Cambridge, Mass.
They also were reluctant to comment on Dr. Schatten's statement, saying that the questions were serious and that they needed to know more about what had happened.
Dr. Schatten's statement referred to a news article published in the journal Nature in May 2004, two months after Dr. Hwang's group published a paper in Science reporting that they had produced human embryos by cloning and had extracted their stem cells.
The Nature article reported that one of the doctoral students in Dr. Hwang's laboratory said she and another woman there had donated eggs for the experiment. If true, it could be an ethical breach, since the donors were supposed to have no connection to the experiment and no possibility of benefiting from it. As a Ph.D. student, the woman might have felt pressured to donate eggs and might have benefited from it.
The article said, however, that Dr. Hwang had denied that the woman was an egg donor and that the woman then said she had not donated eggs. She said there had been a misunderstanding because her English was poor. Dr. Hwang told a reporter for Science that the woman had tried to say she would like to donate eggs to other research groups, not that she had donated eggs to her own group.
Dr. Schatten said in his news release: "Professor Hwang told me that he had no knowledge of ethical violations in the way oocytes were obtained for his research. Because of my trust in him as a colleague, I believed him." That changed, he wrote, when "information came to my attention suggesting misrepresentations might have occurred."
Human eggs are needed for cloning because they are the only way scientists know to take a specialized adult cell, like a skin cell, and revert it to the state it was in when sperm fertilized egg.
In the United States, ethical guidelines issued by the National Academy of Sciences say that women who donate eggs for embryonic stem cell research must be anonymous and cannot be paid for their eggs.