New Criticism Rages Over South Korean Cell Research

A new round of criticism has broken out in South Korea over the accuracy of a recent article that reported a striking advance in human stem cell research.

In the June 17 article, Hwang Woo Suk, a veterinary researcher at Seoul National University, reported that he had developed embryonic stem cell colonies from 11 patients. The article, published in the journal Science, was hailed as a major step toward the goal of treating patients suffering from many serious diseases with their own, regenerated tissues.

But Dr. Hwang's research, though praised by the South Korean government, faces mounting criticism from some Korean scientists. The newest questions about the paper concern DNA fingerprint tests carried out to prove that the embryonic stem cell colonies were indeed derived from the patient in question. The test, demanded by referees for Science, was necessary because cell colonies often get mixed up or overgrown by other cells in even the best laboratories.

Usually any two DNA fingerprint traces will have peaks of different heights and alignment and different background noise. But in several cases the pairs...