by Richard M. Doerflinger
August 26, 2005
New advances in stem cell research are rebutting politicians' claim that taxpayers must be forced to subsidize the killing of human embryos.
Some advances involve "reprogramming" adult cells to act more like embryonic stem cells. In one study, published in Science on August 26, researchers fused existing embryonic stem cells with adult skin cells, producing a new embryonic stem cell with the genetic makeup of the adult cell.
Ethical and practical problems remain. The technique still uses a stem cell originally obtained by destroying a human embryo. Some think this ethical problem may ultimately be solved by isolating the factors in stem cells that achieve this "reprogramming" and manufacturing them directly. Researchers also have to determine the best way to remove the DNA of the old stem cell, so the new fused cell has only the genetic makeup of the adult cell.
Already, however, this advance is undercutting two arguments for government-sponsored destruction of human embryos.
First, it undercuts the argument that new embryos must be destroyed in the name of embryonic stem cell research. Regrettably, even current federal policy funds research using stem cells that were obtained by destroying embryos before August 2001. Many in Congress say that policy must now expand to promote the killing of new embryos, because the old cell lines are limited in number and becoming genetically abnormal over time. But if those old cell lines can be used to make brand new stem cells with the normal genetic makeup of adult cells, at least the argument for destroying new embryos falls apart.
Second, it undercuts so-called "therapeutic cloning," where human embryos are cloned and then destroyed for their stem cells. Patients' own cells can be used to make new embryonic stem cells that are a perfect genetic match to them, without making an embryo who is then destroyed. The medical argument against a complete ban on human cloning becomes obsolete.
Let's also not forget the broader question: Why do we need embryonic stem cells at all? Despite a quarter-century's research in mouse embryonic stem cells, and seven years in the human variety, even the latest studies show disappointing results and a troubling tendency for these cells to form tumors. South Korean cloning expert Curie Ahn recently said that developing therapies may take "three to five decades" (AP, 5/20).
That makes new advances in non-embryonic stem cells even more important. For example, British and American researchers have discovered a stem cell in umbilical cord blood that seems as versatile as embryonic stem cells. According to the August issue of Cell Proliferation, they also learned how to multiply these cells in the lab for clinical use, using "microgravity" technology developed by NASA for experiments in space – and the U.S. team is working to make these cells produce islet cells for treatment of diabetes.
Any way you look at it, good news is popping up all over on the stem cell front – except for those who keep insisting we must kill to cure.
(Mr. Doerflinger is Deputy Director of the Secretariat for Pro-Life Activities, U.S. Conference of Catholic Bishops.)