Preliminary results of the ground-breaking research were disclosed yesterday evening on the Science magazine web site and the Harvard researchers arranged to discuss their findings in more detail today.

They said they were able to show in their early research that the fused cell "was reprogrammed to its embryonic state."

"If future experiments indicate that this reprogrammed state is retained after removing the embryonic stem cell DNA - currently a formidable technical hurdle - the hybrid cells could theoretically be used to produce embryonic stem cells lines that are tailored to individual patients without the need to create and destroy human embryos," said a summary of the research reported on the Science site.

That could lead to creation of stem cells without having to use human eggs or make new human embryos in the process, thereby sidestepping much of the controversy over stem cell research.

The Harvard researchers used laboratory grown human embryonic stem cells - such as the ones that President George W Bush has already approved for use by federally funded researchers - to essentially covert a skin cell into an embryonic stem cell itself.