Scientists push for fresh embryos in stem cell research
May 9, 2008
Governments worldwide should approve the use of fresh human embryos in stem cell research and should follow Canada’s guidelines for permitting the practice.
Bruce Brandhorst, a developmental biologist and chair of Simon Fraser University’s Department of Molecular Biology and Biochemistry, is among eight researchers who make that argument in a newly published article.
Their commentary, The Use of Fresh Embryos in Stem Cell Research: Ethical and Policy Issues, appears in the May 2008 issue of Cell Stem Cell, leading international journal on stem cell research.
Five of the authors are current or former members of the Stem Cell Oversight Committee (SCOC) of the Canadian Institutes of Health Research (CIHR). Brandhorst is a current member. The SCOC oversees the interpretation and application of guidelines for research involving human embryonic stem cells in Canada.
CIHR created the guidelines and SCOC to resolve policy and ethical issues. Canada is the only country with a policy that explicitly addresses the ethical use of fresh human embryonic stem cells to propagate new stem cell lines. The stem cells are derived from excess embryos created in fertility clinics. These embryos are normally stored frozen until patients no longer want them.
There is a worldwide demand for more new embryonic stem cell lines to test new therapies for diseases such as diabetes and Parkinson’s. The authors argue that fresh embryos, even those that are unsuitable for use infertility clinics, have proven to be useful sources of embryonic stem cells for research, such as drug testing for treatment of hereditary diseases. Yet few countries have policies concerning the use of fresh embryos and some ban their use.
The authors consider why some patients opt to donate spare fresh embryos for research and discuss the ethical issues related to their use. They argue that the CIHR’s guidelines provide appropriate ethical oversight, particularly with regard to informed consent by patients donating embryos.
“Approximately, 35 per cent of frozen embryos do not survive the freeze-thaw process,” says Brandhorst. “So more embryos are required to produce stem cell lines from frozen-thawed embryos than from fresh ones.”
Brandhorst adds that more than 100,000 potentially useful fresh human embryos are discarded by fertility clinics each year because they fail quality or genetic tests for implantation.
Brandhorst and the other authors argue that Canada’s CIHR policy model for using fresh human embryos to create new stem cell lines addresses two major concerns in many countries.
“The model ensures that in vitro fertilization patients and their partners have adequate time to make an informed decision about whether they want to have surplus fresh embryos donated to stem cell research,” explains Brandhorst. “The model necessitates a two-stage consent process that protects potential donors from being coerced by their treating physician to donate fresh embryos. Someone who wasn’t involved in their treatment asks patients, who initially consented to their spare embryos being used in stem cell research, for confirmation of their initial decision. The confirmation is sought if patients have decided against freezing and storing their unused embryos.”
— 30 — (electronic photo file available on request)