This work was carried out by researchers at Harvard and Columbia universities, and published in the journal Science back in August. I wrote about it at the time: skin cells were taken from an 82-year-old ALS patient and made to de-differentiate into pluripotent stem cells, which were then reprogrammed to form motor neurons, the cell type which degenerates in ALS.
This research is significant for two reasons. First, it describes a method for generating patient- and disease-specific, which carry the mutations associated with ALS and so will likely prove to be very useful for to investigating disease processes and developing drug treatments.
Secondly, the method provides an alternative source of stem cells. It therefore overcomes the ethical and political obstacles to embryonic stem research, leaving researchers unhindered in their efforts to develop cell replacement therapies for ALS and other conditions.