From BBC News:
A US team created the lines by removing single cells from embryos, a process that left them intact, they report in the journal Nature. At present, growing this type of stem cell results in embryo destruction. The researchers say their findings may remove some of the ethical barriers to this field and provide a way of bypassing current US legislation. In 1995, the US Congress passed an amendment stating that the government would not fund research in which human embryos were destroyed.
And in 2001, President George W Bush declared federal funding would only be available for research using the 61 human embryonic stem cells lines already in existence, where a “life or death decision had already been made”. This meant no funding for the creation of new lines – whether from existing embryos or cloned embryos. US stem cell researchers said the funding limits had ensured the US lagged behind in this field of research, limiting new studies to private companies, while pro-lifers hailed the decision. Scientists believe stem cells may one day help to combat a range of diseases, such as Alzheimer’s or Parkinson’s disease, or to repair spinal cord injury.