Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.

Ancient viral invaders help make us, us. The cells of our ancestors millions of years ago may have found a way to turn viral invasion into a good thing. This genetic lemons-to-lemonade tale comes from a team in Singapore that meticulously looked at 650,000 bits of virus genes that have been left behind in our cells after viral infections.

Retroviruses like HIV can only replicate by integrating their genes into ours and getting our cellular machinery to make new copies of themselves. Biologists have long known that they often leave behind bits of their genes, but had assumed this became part of the “junk DNA” that does not serve any function and that makes up the bulk of the genetic material in our cells. That scenario has started to change over the past few years as teams have reported examples of those retroviral genetic elements playing a role in the regulation—the turning on and off—of our functional genes.

Jonathan Goke, the lead researcher on the project at the Genome Institute of Singapore, wrote that roughly 1,400 of those viral gene elements were involved in the very early stages of embryo development, helping determine how cells decide to mature into different types of tissue. They seem to be needed for determining who we are.

In an article on the website science 2.0 Goke speculated that these viruses may have been able to speed-up evolution by making changes in gene function faster than random mutation.

Blood stem cell transplants under used. Even as the number of blood stem cell transplants ever performed has passed the one million mark, a new report warns that lives are at risk because too many patients that could benefit are not getting these transplants. Blood stem cell transplants, which started as bone marrow transplants, provide the only shot at life-saving therapy for many patients, mostly those with blood cancers.

An international team, led by Dietger Niederwieser of the University Hospital Leipzig in Germany, found a dramatic under use of donor cells for transplants that varied widely around the world. Writing in the Lancet they reported that just 0.4 people per 10 million in the Philippines get such transplants, but in Israel the number shoots up to 506. The report noted both uneven distribution of resources needed to perform the complex procedure and inconsistent support for and participation in donor registries. Niederwieser was quoted in a press release from the journal picked up by ScienceDaily:

“Patients, many of them children, are facing a life and death situation. Ultimately they will die if they cannot get the treatment they need. All countries need to provide adequate infrastructure for patients and donors to make sure that everyone who needs a transplant gets one, rather than the present situation in which access remains restricted to countries and people with sufficient resources.”

What is real with stem cells and joint pain? Bethesda Magazine, the local publication for the county that is home to the National Institutes of Health (NIH), produced a good piece giving the perspective of patients wanting to avoid joint replacement surgery as well as scientists leery of cell-based procedures that have very little evidence to back them up.

The magazine reached out to its neighbor, the NIH to provide some perspective. It quotes Pamela Robey, the co-coordinator of the NIH Bone Marrow Stromal Cell Transplantation Center—those stromal cells are one type of cell often touted by clinics offering to treat joint pain.

“There are a huge number of clinical trials, but there has been next to no published information. The bottom line is there’s no real rigorous data showing it is actually repairing the joint.”

The author also talked to CIRM grantee Larry Goldstein of the University of California, San Diego, in his role as a member of the Ethics and Public Policy Committee of the International Society for Stem Cell Research. He notes that what clinics are offering is unproven and the author directs readers to the ISSCR web site’s “Closer Look” section to get more information on how to evaluate potential therapies they may be considering.