When we think of extinct animals, probably the first one that comes to mind is a dinosaur. But most of us are likely happy to think of these enormous creatures being exactly where they will remain – in the past.
Yet other animals have sadly become extinct and the rate at which species are lost is an alarming one, often due to human actions as well. One approach for scientists has been to look at the potential of stem cells to revive rare animals and increase the diversity of our animal kingdom. But just how can this be accomplished exactly and what are their challenges?
How the Process Works
To simply summarise how it works, the process involves using frozen material from a dead animal and then reprogramming this material to become sperm and eggs. After, the theoretical outcome is that an extinct animal could be ‘brought back’ to life.
Collaboration to Revive Rare Animals
A zoo in San Diego and the Scripps Research Institute are currently working together to discuss the potential to revive rare animals. In fact, there was a yearly international meeting on stem cell research, where scientists from the Scripps Research Institute talked about current experiments.
In these experiments, researchers had created stem cells from the frozen skin cells of a dead male drill. This animal is a type of endangered monkey found in parts of the world such as Nigeria. The stem cells that scientists had created are known as pluripotent stem cells, which were induced from the skin cells.
Challenges of Creating Stem Cells
To actually create these induced pluripotent stem cells, researchers had to use special viruses. These viruses had been engineered to transport four human genes. The human genes are ones that are known to be able to reprogram an adult cell into an embryonic stem cell format.
Unfortunately, this approach did not work when the researchers tried it with the northern white rhinoceros. Feedback within the team indicated that the next step might be to use rhinoceros versions of these particular genes that are normally used in the procedure.
Another issue involved in the goals of reviving rare animals is that when scientists reprogram genes, there is also the chance that the induced pluripotent stem cells could become cancerous ones. The good news is that other research teams have been hard at work to create techniques that make induced pluripotent stem cells without leaving gene copies behind.
Creating Sperm and Eggs from Dead Animals
The ultimate goal with these experiments is to eventually trigger the induced pluripotent stem cells into sperm and eggs. The zoo in San Diego has retained animal tissues as part of a special and unique project. The zoo currently has more than eight thousand samples from more than eight hundred different species.
Bringing Animals Back to Life
Researchers would like to see some of these animals brought ‘back to life’ to add genetic diversity to their captive breeding initiatives. It is an incredible challenge but would essentially be breeding animals that are dead – a surprising and unusual concept for most people to take on board but an exciting one all the same.