Stem cells offer great hope for curing degenerative diseases like Alzheimer's and Parkinson's, and restoring damaged spinal cords.

The researchers have pioneered a way of reprogramming adult cells into embryonic stem cells that can replace cells in nerves, tissue and organs lost through disease or accident.

The embryonic stem cells are laboratory grown from existing lines and do not require destroying embryos. That would surmount a principle moral objection to stem-cell research.

Other Countries Have Stepped Up Research

Under an order from President Bush, federal funds for stem-cell research are limited to a few pre-existing lines that researchers have said are inadequate.

The states have aggressively moved to fill the gap, with California allocating $3 billion to fund research projects.

With the US government -- the largest underwriter of medical research in the world -- on the sidelines, other countries have aggressively stepped up their own research programs.

The Senate is likely to vote next month on whether to overturn the president's ban, which Bush has said he'll veto if the bill passes.

Great Hope for Curing Degenerative Diseases

Although by no means a foregone conclusion, stem cells offer great hope for curing degenerative diseases like Alzheimer's and Parkinson's, and restoring damaged spinal cords.

The Harvard researchers stressed that "formidable" technical hurdles remain, the technology is still preliminary, and it is not a replacement for existing stem-cell research being done on embryonic cells discarded by fertility clinics.

Said researcher Kevin Eggan: "This is the first step down a long and uncertain road." Still, it is an important and promising first step.