TORONTO, March 30, 2004 (LifeSiteNews.com) – In a review of relevant literature, Dr. John Shea of Toronto has found experts have determined that, despite huge media attention, there is little prospect for embryonic stem cell treatment for humans. Dr. John Gearhart of Johns Hopkins University has recently stated that embryonic stem cells are “surprisingly genetically unstable” in mice and perhaps in humans as well. He said that this “may complicate efforts to turn cells into cures. You may have to establish hundreds of cell lines to get the few you would want to have.” This would require destroying thousands of embryos, and replacing them with thousands more when the original cell line becomes too unstable for further use. It is difficult to prevent embryonic stem cells from turning into all kinds of cells and tissues. Bioethicist Glenn McGee has stated that “The potential that they would explode into a cancerous mass after stem cell transplant might turn out to be the Pandora’s box of stem cell research.” (E.Jonietz, “Innovation: Sourcing Stem Cells” Technology Review, Jan/Feb. 2001) A study published in Science, July/2001, showed that embryonic stem cells used in cloning mice created with embryonic stem cells had many faulty genes due to gene expression flaws. These faults were not due to cloning but to the embryonic cells. These genetic defects often led to severe abnormalities in the mice.
Rudolf Jaenisch of the Whitehead Institute for Biomedical Research in Cambridge, Mass., warned that gene expression flaws could affect personality, intelligence and other human attributes in cloned humans. In February 2004, he stated that embryonic stem cell research is not of practical use at this point. Dr. Carlo Croce M D., Director of the Kimmel Cancer Center, of the Thomas Jefferson University, Pa. stated on March 15, 2004, that a 100% identical clone that is not subject to tissue rejection can be produced only if one uses the patient’s own egg cells. Thus for male patients, or for women in menopause, the possibility of therapeutic cloning does not yet exist. Dr. Croce foresees other problems with embryonic stem cells. Animal experiments have shown that serious cancer frequently develops when animals receive manipulated embryonic stem cells. He believes that the carcinogenic risk is serious, and that it will be a long time before any patients could be treated with cloned embryonic stem cells.