If you've followed the latest medical research, you know that stem cells are a big deal. They let you repurpose cells so that you can theoretically grow them into whatever you need. However, scientists just got a good reason to be more cautious than they have in the past. A Harvard team has discovered that five of the 140 human embryonic stem cell lines registered for research use in US labs have cells whose mutations can cause cancer. Two of the lines have been used in human trials, too. None of those patients has developed cancer, thankfully, but there's a "very real risk" it could happen.
This doesn't mean that the medical community is about to hit the brakes on stem cell research. There's still some review necessary to decide what happens next. And there are ways to make sure cells are healthy before they're used. However, this raises the possibility that there are other, less common mutations that haven't been caught. And these stem cell lines have been in use for nearly 20 years -- that's a lot of time for risks to go unchecked.
If the discovery holds up, researchers may have little choice but to look for mutations through DNA sequencing, which is expensive at about $1,000 for every genome. That screening could soon be government-mandated, in fact. Still, it might be necessary to make sure that stem cell treatments aren't just substituting one disease for another.