Group urges gov't to strictly limit chimp research

Chimpanzees should hardly ever be used for medical research, a prestigious scientific group told the government Thursday - advice that means days in the laboratory may be numbered for humans' closest relatives.

New ethical questions are being raised in stem cell research

A groundbreaking discovery two years ago that turned ordinary skin cells back into an embryonic or "pluripotent" state was hailed as the solution to the controversial ethical question that has plagued stem-cell science for ...