The world needs a biobank that holds tissues from endangered animals — a real-life equivalent of Noah’s ark — to save species from extinction, Ian Wilmut, creator of Dolly the sheep — the world’s first mammal cloned from an adult somatic cell — said Monday. Wilmut, an embryologist from the University of Edinburgh in the U.K., made the comments on the eve of the 20th anniversary of Dolly’s birth in 1996.
“The absolute minimum we should do is preserve tissues from these animals in such a way they can be thawed and grown again,” Wilmut reportedly said, referring to animals that are at risk of extinction.
Currently, one in four mammals, one in eight birds, one third of all amphibians are believed to be at risk of extinction — a huge majority of them pushed to the brink due to human activities such as anthropogenic climate change and deforestation.
The idea is to create a biobank of animal cells — sperms, eggs and tissues — similar to the Svalbard seed vault that is home to millions of plant seeds from across the globe. According to Wilmut, the preserved eggs and sperm can then be used to make viable embryos. However, he acknowledged that for that to happen, certain scientific hurdles would still need to be overcome, especially since the embryos would only be transplanted into a female member of another species.
Once this problem is tackled, there are two ways the stored cells can be used to create entire organisms — by inducing pluripotency, through which cells can be primed to differentiate into particular cell types, or through a technique known as CRISPR, wherein individual fragments of an organism’s DNA can be used to make incremental changes to living species over a period of several generations.
“We are looking some distance into the future, but people are beginning to develop abilities to produce gametes (sperm and egg cells) from iPS [induced pluripotent stem] cells,” Wilmut said. “I would presume that one day, with the species which are really studied, we will be able to produce gametes, and therefore embryos.”
So far, though, attempts to bring back extinct animals through cloning have been largely unsuccessful — although scientists have been successful in implanting the woolly mammoth's DNA in elephant cells isolated in a petri dish. For instance, in 2009, scientists cloned the Pyrenean ibex — a mountain goat that went extinct in 2000 — using DNA taken from preserved skin samples, but the newborn ibex died shortly after birth.