Can frozen DNA help species survive extinction? San Diego’s Frozen Zoo, conservationists partner to put biodiversity banking on the map

Emily Alvarenga | The San Diego Union-Tribune

For nearly half a century, the San Diego Zoo Wildlife Alliance has been taking the fantasy world of “Jurassic Park” from fiction to reality — minus the dinosaurs and destruction.

As wildlife populations plummet and biodiversity is lost worldwide, the alliance has been working to collect and preserve genetic samples, taken during routine exams or after animals have died, from as many species as it can with what it calls its Frozen Zoo.

Now its conservation efforts are being recognized globally, as it was designated Wednesday by a major conservation group as its first-ever center focusing on gene banking to help rare and endangered species survive.

The Species Survival Commission of the International Union for Conservation of Nature — the world’s largest conservation organization — has partnered with the wildlife alliance to form the union’s newest Center for Species Survival.

It will be one of the organization’s just 17 such centers around the world and the only one to focus on a specific strategy to prevent species extinction, such as biodiversity banking, rather than on a particular species or environment.

The announcement is an indicator of the San Diego Zoo Wildlife Alliance’s progress in gene banking and the promise of its efforts in helping endangered wildlife survive through reproductive assistance, stem cell therapy and cloning.

In recent years, it has led to advances scientists hope could make cloning viable enough to help restore wildlife species — provided they prove capable of successfully breeding.

While there are “Jurassic Park” connections — the art director of Steven Spielberg’s film found inspiration from the Frozen Zoo and from the Safari Park’s entry gates — that work isn’t the stuff of science fiction.

Biodiversity banking, or biobanking, refers to the process of preserving living cells, tissue, eggs or sperm, seeds and other biomaterials. Those genetic materials are carefully frozen in liquid nitrogen so they can be studied and used for years to come.

“This loss of genetic diversity is our fault — it’s because of our actions — so we are actually resolving an ethical problem,” said Barbara Durrant, director of reproductive sciences at the San Diego Zoo Wildlife Alliance.

The survival of the northern white rhinoceros and dozens of other species could hinge on these preserved cells amassed in the last nearly 50 years, according to the organization’s researchers.

The local collection has become the largest and most diverse of its kind. To date, the Frozen Zoo contains nearly 11,000 living cell cultures representing about 1,280 different species and subspecies of rare and endangered animals.

Biodiversity banking not only preserves unrecoverable genetic diversity in wildlife species — potentially giving them better chances at withstanding environmental factors — but also expands the capacity for genetic research and rescue, making “an everlasting contribution to conservation,” Durrant explained.

“These cells should be here long after you and I are gone,” said Marlys Houck, curator of the Frozen Zoo.

Locally, a cloned Przewalski’s horse named Kurt born in August 2020 was among the first genetic milestones in the alliance’s efforts to help restore endangered animal populations.

He’s the world’s first successfully cloned Przewalski’s horse, a breed native to Mongolia and formerly extinct in the wild. They were reintroduced to their natural habitat in recent years and are now the only true wild horse left in the world.

Named for Kurt Benirschke, who founded the Frozen Zoo, the horse was cloned from skin cells taken from a stallion in 1980 and cryogenically safeguarded.

Now 3 years old, scientists hope Kurt can soon start helping to further safeguard his species by joining the herd of Przewalski’s horses at the park as part of a conservation and breeding program.

But before that can happen, Kurt has to learn how to be a wild horse. He’s spent the last year doing so in the Safari Park’s Central Asia field habitat alongside Holly, a female Przewalski’s who’s just a few months older.

Though not always easy — it includes some kicks to the face — learning the behavioral language will help him secure his place in the herd.