U.S. researchers at Advanced Cell Technology have developed a method to make embryonic stem cells that do not harm mice embryos. It is likely that the method can be applied to human embryos.
In their experiment, the ACT researchers, headed by Robert Lanza, let a fertilized mouse egg divide three times (one cell to two cells; two to four; and four to eight).
With eight cells inside the egg (at the stage before a cell mass, called a blastocyst, becomes implanted in the womb—or the embryonic stage), they remove one cell and, then, let the remaining seven cells grow normally just like the eight-cell egg would nominally grow.
They state that the removal of one cell did not change the way the seven-cell egg developed when compared to the eight-cell egg. In fact, it was stated that one cell is already used as a test called preimplantation genetic diagnosis (PGD, also called Embryo Screening), which is used to evaluate for genetic defects within the human embryo.
It is being reported that the PGD test has been shown not to affect the development of the seven-cell egg any differently than the eight-cell egg.
If this technique can be applied successfully to humans, then it could provide scientists with a new source of cells and allow children born using the PGD test to have the one cell divide once—using one cell for the test and the other cell for growing embryonic stem cells to combat future degenerate diseases .