A team of South Korean researchers has found that being on the cutting edge of controversial research brings both plaudits and scrutiny. In March they garnered headlines for the first successful production of a human embryonic stem cell line from cloned human cells (Science, 12 March, p. 1669; published online 12 February). But in a news story in the 6 May issue of Nature, the group was blasted for possible ethics violations. Specifically, Nature reported that the group, led by veterinary cloning expert Woo Suk Hwang and gynecologist Shin Yong Moon of Seoul National University, may have improperly used one of the 15 co-authors as an egg donor. Hwang emphatically denies that charge. But since then, other questions have arisen, suggesting that scientists involved in such sensitive research are going to have to carefully toe the line to avoid gray areas of ethical impropriety.

According to the paper and accompanying online material, 16 volunteers underwent hormone treatment to stimulate overproduction of maturing eggs, creating a total of 242 eggs. The authors say that the women donated specifically for this experiment, were not compensated, and were informed that they would not personally benefit from the research.