Back to the (Frozen) Future

Flash back nearly 30 years ago to 1987. Gas was 89 cents a gallon, Ronald Reagan was president, “Dirty Dancing” was in theaters, Los Lobos had their hit single “La Bamba” and there were 50 northern white rhinos. Nola, the beloved rhino who lived at the Safari Park until her death in late 2015, was only a teenager. She lived with a small breeding group of other northern white rhinos at a zoo in the Czech Republic. But rhino populations were in trouble even back then, particularly Nola’s subspecies.

In 1987, San Diego Zoo Global Institute for Conservation Research (called CRES at the time) was just over a decade old and actively involved in saving species like the California condor. The Frozen Zoo® had already reached a landmark of over 900 living cell lines from dozens of mammal species thanks to the vision of Dr. Kurt Benirschke, founder of CRES and the Frozen Zoo®.  “Dr. B”, as he was fondly known, and his dedicated cell culturists were banking living cells from as many species as they could. There were even cell lines from four of the five existing rhino species, the only collection in the world able to claim that accomplishment. 

The problem was that rhino cells grew poorly; the secret to getting them to thrive needed to be figured out, and fast! All rhino species were in decline due to habitat loss and poaching for their horn. Although the technology wasn’t available yet, it was thought that cells derived from small pieces of skin would someday be the best hope for reviving imperiled species.

That same year, the Genetics Division at CRES received grant funding to hire a technician for one year. The goal for the tech was straightforward and challenging: figure out how to get rhino cells to thrive and determine the chromosome number in Sumatran and white rhinos. It was hard to imagine that so much was still unknown about such charismatic species. I was thrilled to be chosen for the position and rather surprised, too, since I had only come to see if I could volunteer my experience in cell culture and karyotyping (chromosome maps).  

Now to the present. With Nola’s death there are only three northern white rhinos remaining, all heavily guarded at a preserve in Kenya. None of them are able to reproduce due to age and health issues. It seems this subspecies is destined for extinction, an iconic animal disappearing during our lifetime. 

But there’s hope! Thanks to the far-sighted thinking of people like Dr. B, along with support from San Diego Zoo Global, the Frozen Zoo® has cell lines from 12 northern white rhinos collected over the past 35 years. Technology has finally caught up with the vision of using these cells in an ambitious attempt to rescue the subspecies. The recent discovery of methods that turned mouse skin cells into stem cells and then gametes (eggs and sperm) gives us hope that the same could be done with our banked rhino cells. You can read more about the rhino rescue project in the July 2016 issue of Zoonooz:

Back in 1987 I couldn’t have imagined where my project of getting the rhino cells to thrive would lead. I froze cells from Nola and others in her group way back in 1992 and now these cells are an important part of the rhino rescue project.  It’s rewarding to know that my contribution could help bring this amazing species back from the brink of extinction.

Thirty years have zipped by, and yes, I’m still adding cells to the Frozen Zoo®, but mainly overseeing a small team of super talented technicians who continue the hope for saving species with every cell line they add. 

The Frozen Zoo® now has nearly 10,000 individuals from 1,000 species of mammals, birds, reptiles and amphibians. We put a high priority on banking as many new species as possible.  Who knows what could be achieved in the future, using cells we are saving today! 

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