The Promise of Stem Cells
Normally, cells develop from stem cells into a myriad of increasingly more specialized cell types during early development and throughout a lifetime. In humans and other mammals, these developmental events are usually irreversible. This means that when tissues are damaged or cells are lost, the body has limited means by which to replenish them.
Having a source of stem cells would be useful in many medical situations because these cells are "pluripotent," having the ability to become any of the body's cell types. Pluripotent stem cells would potentially provide physicians with the ability to replace or repair damaged tissues throughout the body. For example, pluripotent stem cells could be differentiated into the damaged cell type and transplanted.
Much research on pluripotent stem cells to date has been conducted on human embryonic stem cells, which are harvested from discarded embryos (those created but not used for the purposes of in vitro fertilization, a technique to help couples conceive). However, recently another source of pluripotent stem cells has come onto the scene. These cellscalled induced pluripotent stem cellsare created by taking a sample of skin cells or another type of differentiated cell and using chemicals and molecular biology techniques to coax them back into a pluripotent state.
The current analysis included 47 human embryonic stem cell lines collected from labs located around the worldincluding Korea, Australia, and Finland. The analysis also included five induced pluripotent stem cell lines.
Ancestors Forgotten and Remembered
To determine the ethnic origins of the stem cell lines and to link them to genetic "signatures" that might affect medical outcomes, the scientists drew o
|Contact: Keith McKeown|
Scripps Research Institute