By Will Dunham
Oct 14 (Reuters) - A US biotech company says it is making progress toward its goal of resurrecting the dodo, the famous flightless bird with a large hooked beak, and returning it to its native Indian Ocean island of Mauritius, where humans drove it to extinction in the 17th century.
Dallas-based Colossal Biosciences said on Wednesday it has used a newly developed AI platform to identify genetic changes that may be responsible for the dodo's distinctive craniofacial traits as its scientists
pursue gene-editing targets to bring back this lost species.
Colossal is planning to perform gene-editing to bring dodo traits into the cells of its closest living relative, the Nicobar pigeon. Native to some Southeast Asian islands, the Nicobar pigeon is known for its shimmering green and copper feathers and, unlike the dodo, can fly.
The company said it is in the final stages of its analysis of the dodo genome, now filled to 95%. It also said it has made an advance that should shorten the time needed to test whether a genetic edit produces the desired trait. The company did not announce a timeframe for hatching a dodo.
Colossal says it is dedicated to "de-extinction" — resurrecting vanished species. Last year, it said it had genetically engineered the dire wolf by editing the genes of the gray wolf, the extinct Ice Age predator's closest living relative, to add dire wolf traits.
Besides the dodo and dire wolf, Colossal has four other species on its de-extinction list: the woolly mammoth; the thylacine, also called the Tasmanian tiger; the bluebuck antelope; and the moa, a large flightless bird.
"The dodo is the world's best-known symbol of extinction caused by people. It disappeared within decades of humans arriving on Mauritius, largely because of the introduction of invasive species like rats and other animals they brought. Bringing it back shows extinction doesn't have to be permanent," Ben Lamm, Colossal's CEO and co-founder, told Reuters.
"The big hurdles ahead are proving which genetic changes really matter, making many of those edits in a bird and passing them to the next generation, and preparing a safe home for dodos on Mauritius," Lamm said.
The dodo was a ground-nesting bird about 3 feet (1 metre) tall and weighing up to about 50 pounds (23 kg). Having never encountered humans, dodos exhibited no fear of the people who reached Mauritius in the 16th century. Pressured by invasive species and human hunting, the last living dodo was seen in 1662. It has remained alive in popular culture including in Lewis Carroll's book "Alice's Adventures in Wonderland."
GENOMORPH PLATFORM
Ancient DNA is always broken into small pieces, so no ancient genome is perfectly complete, including that of the dodo.
The new AI platform Colossal built is called GenoMorph.
"The challenge was scientists only have one complete dodo genome, making it difficult to distinguish the genetic differences that made the dodo unique from ordinary genetic variation. GenoMorph effectively acts as a 'treasure map' for the dodo genome, narrowing hundreds of thousands of possible genetic changes into the targets most likely to explain its iconic beak and facial structure," Lamm said.
Beth Shapiro, Colossal's chief science officer, said GenoMorph finds likely gene-editing targets for species with very little surviving DNA. Normally scientists compare many genomes from one species to find the genes behind a trait, but this is not possible with the dodo, Shapiro said.
"So instead, GenoMorph studies how skulls and beaks develop across more than 70 living bird species and learns which genetic switches control their shape. It gave us a shortlist of about 2,300 candidates linked to beak size and shape. These targets are now being validated in the lab," Shapiro said.
Colossal said it has expanded its colony of Nicobar pigeons in Texas to 36 birds following successful breeding among established pairs. It said this should help in studying Nicobar pigeon development, reproduction and genetics.
Lamm said the company is working with Mauritian scientists, conservation groups and the Mauritius government on what bringing the dodo back to its native land might look like.
"Getting Mauritius ready for dodos also means removing invasive predators and restoring habitat, which helps the native species living there now," Lamm said. "No release sites will be chosen until the ecological work and community consultation are finalized, but it is Colossal's goal to put our dodos back into their natural habitats in Mauritius."
(Reporting by Will Dunham in Washington; Editing by Daniel Wallis)
