Despite its promise, stem cell research in the U.S. has been stymied, time and again, by bioethical landmines. The explosive debate revolves around the fact that, until recently, the only way to get pluripotent stem cells was to extract them from human embryos left over from in-vitro fertilization—a process that destroyed the five-day-old embryo. The ongoing debate about when life begins has led many to oppose stem cell research on the grounds that it is immoral to destroy something that could eventually grow into a person. On the other hand, promoters argue that the potential to help millions of people with stem cell therapies outweighs the sanctity of cells that are not viable outside the womb and that often go unused. Arguments on both sides are based on personal beliefs that may never be reconciled, so the debate hinges on whether the federal government should fund research that many citizens find morally objectionable. The following box chronicles stem cell research regulation in the U.S. 


The Supreme Court legalizes abortion in 1973. The ensuing debate on the ethics of experimenting on fetal tissue prompts Congress to issue a moratorium on federal funding for research on human embryos the following year.


In 1995 President Clinton lifts the ban on funding for study of stem cells left over from in-vitro fertilization, but leaves other restrictions in place. In response, Congress passes the Dickey-Wicker Amendment, prohibiting funding for all research “in which a human embryo or embryos are destroyed, discarded, or knowingly subjected to risk of injury or death,” regardless of the source of the embryo.


President George W. Bush announces that federal funding will be made available for research on the approximately 60 existing embryonic stem cell lines, but not new ones. Congress twice votes to loosen the restrictions on funding for research using embryonic stem cells left over from in-vitro fertilization but President Bush vetoes the legislation both times.

In 2009, early in his first term, President Barack Obama removes the ban on federal funding for new stem cell lines but signs an omnibus bill preserving the Dickey-Wicker Amendment. The move retains restrictions against federal funding for the direct creation of new stem cell lines, but opens up funding for research on newly created lines developed with private or state money. 


In 2012 stem cell biologist Shinya Yamanaka wins the Nobel Prize in Physiology or Medicine for discovering how to reprogram adult skin cells into pluripotent stem cells. Going forward, policy makers will have to determine whether Yamanaka’s induced pluripotent stem cells (iPS) will face the same regulations as human embryonic stem cells or if new legislation is needed.