Scientists and advocacy groups view embryonic stem cell research as perhaps the best hope for finding cures for debilitating diseases like Alzheimer's and Parkinson's.

CNN: Bush to allow limited stem cell funding

Mr Obama repeated the claims of some scientists that embryonic stem cell research could lead to a cure for a whole host of diseases like Parkinson's, Alzheimer's and diabetes and that it could even help someone who is paralysed to walk again.

BBC: Another Bush policy overturned