These new embryonic cells are, like stem cells, capable of transforming into multiple different types of tissue.
Currently, retroviruses and genes are used to complete this transformation, but this carries the risk of cancer and other problems. Using microRNAs, which regulate gene expression, would be a potentially safer method, said researchers from the University of California, San Francisco.
There's more on stem cells at the U.S. National Institutes of Health.
SOURCES: Ji Wu, Ph.D., professor, Shanghai Jiao Tong University, Shanghai, China; Darwin J. Prockop, M.D., Ph.D., director, Texas A&M Health Science Center College of Medicine Institute for Regenerative Medicine at Scott & White, and Stearman Chair in Genomic Medicine and professor of molecular and cellular medicine, Texas A&M Health Science Center College of Medicine; George Attia, M.D., associate professor, reproductive endocrinology and infertility, University of Miami Miller School of Medicine; Paul Sanberg, Ph.D., D.Sc., distinguished professor, neurosurgery and director, University of South Florida Center for Aging and Brain Repair, Tampa; April 12, 2009, Nature Cell Biology, Nature Biotechnology