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The recently extinct Pyrenean ibex has been resurrected by cloning cryopreserved tissue samples:
Pyrenean ibex, which have distinctive curved horns, were once common in northern Spain and in the French Pyrenees, but extensive hunting during the 19th century reduced their numbers to fewer than 100 individuals.They were eventually declared protected in 1973, but by 1981 just 30 remained in their last foothold in the Ordesa National Park in the Aragon District of the Pyrenees.
The last bucardo [Pyrenean ibex], a 13-year-old female known as Celia, was found dead in January 2000 by park rangers near the French border with her skull crushed.
Dr Folch and his colleagues, who were funded by the Aragon regional government, had, however, captured the bucardo the previous year and had taken a tissue sample from her ear for cryopreservation.
Using techniques similar to those used to clone Dolly the sheep, known as nuclear transfer, the researchers were able to transplant DNA from the tissue into eggs taken from domestic goats to create 439 embryos, of which 57 were implanted into surrogate females.
Just seven of the embryos resulted in pregnancies and only one of the goats finally gave birth to a female bucardo, which died a seven minutes later due to breathing difficulties, perhaps due to flaws in the DNA used to create the clone.
Despite the highly inefficient cloning process and death of the cloned bucardo, many scientists believe similar approaches may be the only way to save critically endangered species from disappearing.