Rare horse cloned from cells taken from a stallion in 1980

Kurt, a tiny horse who is actually a clone, is seen in this September 1, 2020, photo provided by San Diego Zoo Global. CHRISTINE SIMMONS/SAN DIEGO ZOO GLOBAL VIA AP

Little Kurt looks like any other baby horse as he frolics playfully in his pen. He isn’t afraid to kick or head-butt an intruder who gets in his way and, when he’s hungry, dashes over to his mother for milk.

But 2-month-old Kurt differs from every other baby horse of his kind in one distinct way: He’s a clone.

The rare, endangered Przewalski’s horse was created from cells taken from a stallion that had sat frozen at the San Diego Zoo for 40 years before they were fused with an egg from a domestic horse.

With the egg’s nucleus removed, ensuring Kurt would be basically all Przewalski’s horse, they were implanted in the mare who would become his mom on August 6.

The result, officials say, was the world’s first cloned Przewalski’s horse.

Scientists have cloned nearly two dozen kinds of mammals, including dogs, cats, pigs, cows and polo ponies. In 2018, researchers in China created monkeys for the first time using the cloning techniques that produced Dolly the sheep.

The zoo sees Kurt’s birth as a milestone in efforts to restore the population of the horse also known as the Asiatic Wild Horse or Mongolian Wild Horse. The small, stocky animals (they stand only about 4 to 5 feet tall at the withers) are believed extinct in the wild and number only about 2,000 in zoos and wildlife habitats. Their limited gene pool puts them at a reproductive disadvantage.

“This colt is expected to be one of the most genetically important individuals of his species,” Bob Wiese, chief life sciences officer at San Diego Zoo Global, which operates the zoo, said in a statement. “We are hopeful that he will bring back genetic variation important for the future of the Przewalski’s horse population.”

Although only 2 months old, Kurt’s birth was made possible in 1980 when cells were taken from a 5-year-old stallion and put in deep freeze at San Diego’s Frozen Zoo facility. His father died in 1998.

Kurt was named for Kurt Benirschke, who played a key role in founding the Frozen Zoo with its extensive research program and cell cultures.

“A central tenet of the Frozen Zoo, when it was established by Dr. Benirschke, was that it would be used for purposes not possible at the time,” said Oliver Ryder, director of genetics at San Diego Zoo Global.