Debate Urged On Gene Therapy

A genetics pioneer wants to try gene therapy on fetuses in hopes of curing them of deadly diseases before they're ever born. However, first he's asking scientists and ethicists to debate the experiment because it could for the first time alter a person's genes in a way that the changes are passed on to future generations.

"We're talking about something that is a radical departure from anything that's ever happened before in medicine," said Dr. W. French Anderson, who performed the first gene therapy in 1990 and now hopes to try it on fetuses. "This is something with profound ethical implications."

A federal panel of genetics experts begins reviewing Anderson's research plans this week. He's still two to three years away from the first experiment on human fetuses. But Anderson requested the unusual early review to force a national debate on whether society's ready.

The debate likely will be hot.

Anderson wants to inject a healthy gene directly into fetuses during the second trimester of pregnancy to try curing two rare diseases: ADA, which renders the body unable to fight even mild infections and is best known as the "bubble-boy disease"; and alpha thalassemia, a type of anemia that in severe cases kills the baby inside the womb. Both diseases are caused by flaws in a single gene.

Anderson, now with the University of Southern California, in 1990 used gene therapy on two girls with ADA. It did not cure them but did improve their condition, and today, with additional drug therapy, they're healthy.

Anderson says gene therapy should work better in fetuses because the healthy genes can slip into more of the tiny patients' cells than they can after birth.

There are some risks, Anderson said. The new gene could accidentally get into the fetus' reproductive cells, the so-called germline, meaning the genetic alteration would be passed on to that person's future children. That's never happened with gene therapy before all genetic changes have affected only the person being operated on.

If the experiment works and the new gene prevents disease, then being passed to future generations would be good for that particular family, Anderson said. However,"you open up the whole field of genetic engineering of future generations," he said. In addition, if somehow the gene messes up, his patients' descendants could face even more risk.

Or the gene therapy could work only partially, meaning a fetus with alpha thalassemia that would otherwise have died in the womb instead could survive a few sickly years before dying, Anderson said.

Anderson's animal experiments have shown for five years that the therapy is possible, but he hesitated to plunge into the controversy. After all, back in 1990, "I got death threats" over the first gene therapy. "It'll happen again."

"This will be a stressful time, but nobody else is going to do it, it needs to be done, the time is right," Anderon concluded.

Written By Lauran Neergaard