Stem cell hope

The WSJ (A1) features an article about stem cells, news of which was out on AP yesterday. Gautam Naik reports on this advance that "avoids destroying embryos."

Japan and U.S. researchers have separately come up with a way to create cells that behave just like embryonic ones (able to differentiate into any kind of cell in the body) out of a clever combination of retroviruses and skin cells. Retroviruses are special kinds of viruses that have been used in the past (as in this case) to replace the DNA of the cell they enter. Scientists can take four genes, insert them into a retrovirus, and inject those viruses into a skin cell harvested from the patient.

The good: This eliminates the dual ethical/moral issues of cloning and destruction of embryos; the technique theoretically has all the advantages of embryonic stem cells, with few of the disadvantages. The cells would also come from the patient, so the risk of immune rejection is minimal.

The bad: This is still theoretical. Also, retroviruses have been "linked with cancer," as have embryonic stem cells, which are prone to generate tumors.