Daley's talk will also highlight the differences between embryonic stem cells and iPS cells, which were first created from adult human cells in 2007. The iPS strategy is an important tool because it can be used to create disease-specific stem cell lines that, like embryonic stem cells, can develop into many cell types. Daley and other scientists are using iPS technology to reprogram cells from patients with diseases such as Lou Gehrig's disease (amyotrophic lateral sclerosis), Huntington's disease, and diabetes. With these "disease-specific" iPS cells in hand, researchers can learn more about how such diseases develop and hopefully identify new therapeutic strategies.

Despite the promise of iPS cells, scientists are still struggling to understand whether their developmental potential is equivalent to that of embryonic stem cells. Some studies have suggested that iPS cells have more fragile genomes or are more prone to DNA abnormalities than embryonic stem cells. This fragility could make them unsafe to use therapeutically. The bottom line, says Daley, is that research on both types of stem cells must continue, because it's too early to predict where the safest and most effective cell-based therapies will come from.

"It's a remarkably fast paced and exciting field," says Daley. "We've had a decade of diversions and distractions, and we as a scientific community are relieved to have a more rational scientific policy, which allows us to focus almost exclusively on the science."

Source: Howard Hughes Medical Institute