CGS-authored

A global consortium designed to pursue a controversial type of stem cell research involving cloned embryos is collapsing amid ethical questions surrounding human egg donations in South Korea.

Pacific Fertility Center, an in-vitro fertilization clinic in San Francisco that was planning to be part of the consortium, said Monday it was pulling out after the withdrawal Friday of the South Korea-based cloning network's primary U.S. organizer, Gerald Schatten of the University of Pittsburgh School of Medicine.

The collapse is a setback for advocates of creating "disease-specific" lines of stem cells, which involves insertion of DNA from patients into human eggs whose own DNA is first removed, a cloning technique known as "somatic cell nuclear transfer." Researchers say disease-specific cell lines can be powerful tools for studying the origins of genetic disease and finding new drugs to cure them.

Laboratories at South Korea's Seoul National University are at the forefront of the nuclear transfer field under the leadership of cloning specialist Woo Suk Hwang. He and colleagues announced the creation of a "world stem cell hub" on Oct. 19 that was...