To make a comparison that would show which genes were uniquely active in the human egg, they used RNA of all parts of the human body - exceptthat of the ovaries, where eggs are produced.
Then the computer analysis began. In a highly sophisticated game of match, every gene in the egg that was found in other tissues was eliminated, so that only unique genes remained.
Cibelli said that the team identified 5,331 human genes that are overexpressed in the egg. Of those, 1,430 are mysteries - their functionunknown.
The group also compared the human egg genes with those of a mouse as well as human and mouse embryonic stem cells. On the final intersection,66 genes were found to be common between the four sets of data.
"There are thousands of genes that are redundant. We found about one in a thousand genes that are unique to the eggs - and some of them, theydon't have a known function yet," Cibelli said. "Now we can clone these genes and put them into cells and see if they may have a role in the creation of stem cells - without fertilization or destruction of human embryos."
Cibelli believes some of those genes know the big secrets - such as when a cell should slow down and later become a cell that can grow into anycell of the human body. The computer work of this preliminary search will give way to further experiments.
Source:Michigan State University