How to make ethical embryonic stem cells

One cell can be safely removed
to make an embryonic stem cell line.
One kind of stem cell is controversial-- embryonic stem (ES) cells. The controversy comes from the fact that scientists have to destroy an embryo to get its stem cells. To people who view the 8-cell embryo as a life, this is not acceptable.

What if we could get ES cells without destroying the embryo? Then there wouldn't be so much controversy. In fact it would be hard to argue against using them unless someone is opposed to in vitro fertilization (IVF).

For a number of years now scientists have been able to take a cell from an embryo and test it for genetic problems. The procedure is called preimplantation genetic diagnosis or PGD.

People have this done if they are having trouble conceiving. Or if they carry in their genes some awful disease that will kill the child very early in life. (Or, more frivolously, to make sure a family has equal numbers of boys and girls-- family balancing.)

Imagine that instead of taking that cell and testing it you instead grew it into a stem cell line. Now the embryo can develop into a child. And the cell can be made into an ES cell line.


This actually worked in mice back in 2005. They took a cell from an 8-cell stage mouse embryo. The 7 remaining cells grew into a healthy pup. And the 8th cell grew into a stem cell line.

Then last year a biotech company called Advanced Cell Technology (ACT) said they repeated the experiment in humans. But they didn’t really. They only did half the experiment.

What they did was make an ES cell line from a single embryonic stem cell taken from a human embryo. But then they didn't go on to grow the embryo to term.

Now there is no reason to think that the embryo could not have grown to term. People do PGD every day and those embryos can grow.

One cell can be safely removed
to make an embryonic stem cell line.
But since ACT didn't do the experiment, everyone focused on that. Instead of the fact that they made a stem cell line from a single embryonic stem cell. And the fact that any child that undergoes this procedure would have a great resource-- his or her own personalized embryonic stem cells.

See, besides the controversy, one other problem with ES cells is that they come from someone else. Which means like any organ transplant, there may be rejection problems.

But this would not be the case for this child. The child would have ES cells perfectly suited for him or her. So when scientists figure out how to cure diseases with ES cells, this child will have them stored away for later use. Lucky kid.

Dr. Barry Starr is a Geneticist-in-Residence at The Tech Museum of Innovation in San Jose, CA.