“Dodo eggs are much, much larger than Nicobar pigeon eggs, you couldn’t grow a dodo inside of a Nicobar egg,” said Jensen. Editing the Nicobar will require thousands of precise DNA changes simultaneously. So far, scientists have struggled to introduce just a single genetic change into quails. Most genetic tools are optimized for mammalian species, but those for birds are sorely lacking. The company plans to extract these flexible reproductive “blank slates” from developing Nicobars and edit their DNA sequences to better match those of the dodo using tools such as CRISPR. True to their name, these cells can transform into both sperm and egg-producing cells. Then there’s the problem of reintroducing a cloned embryo back into the body.Ĭolossal decided to go with a different method for assisted reproduction: using primordial germ cells (PGCs). This stage is hard to capture in avian species because eggs are encapsulated in a hard shell. The embryo is then brought to life inside the surrogate womb of a living species, a method akin to cloning.Ĭloning a species requires access to an egg cell that’s sufficiently developed so it can be fertilized. In mammals, the edited genome-one that resembles the extinct species-is transplanted into an egg cell of its closet cousin and developed into an embryo. By comparing the dodo’s genome sequences to that of the Nicobar, it’s now possible to hunt down DNA changes that define the dodo-and pinpoint genetic changes needed to transform a Nicobar into its long-extinct cousin. The two birds shared a common ancestor roughly 30 to 50 million years ago, wrote Shapiro in a 2016 study.Įarly last year, she announced that her team has sequenced the entire dodo genome from a museum sample, although the results have yet to be published in a scientific journal. Comparing the dodo’s mtDNA with that of their living cousins, the team honed in on the Nicobar pigeon, a peacock-colored bird that roams from the Indian Andamans to the Solomons and New Guinea, as their closest living relative. These genetic codes are passed down solely through the maternal line. Back in 2002, her team sequenced a chunk of the bird’s mitochondrial DNA (mtDNA), which lives inside the cell’s energy-producing factories, the mitochondria. Thanks to Shapiro, Colossal has already nailed the first two steps. Yeah, it’s not exactly a walk in the park. Finally, produce an embryo that can be brought to life in a surrogate species. Step three, screen for genetic differences, and replace the living animal’s DNA code with that of the extinct species. Step two, find its nearest living cousin. Step one, decode the extinct animal’s genome. The de-extinction playbook is already laid out. Whether it’ll work out, he added, remains to be seen. Thomas Jensen, a cell and molecular reproductive physiologist at Wells College, to Nature. “It’s incredibly exciting that there’s that kind of money available,” said Dr. Other experts in the field are cautiously optimistic, if just for the attention brought to conservation. A professor of ecology and evolutionary biology at the University of California, Santa Cruz, Shapiro has had a decades-long fascination with the extinct bird. Beth Shapiro, a scientific advisory board member at Colossal Biosciences. “A goal here is to create an animal that can be physically and psychologically well in the environment in which it lives,” said Dr. Even if the technology works, the resulting “hacked” species would raise a big philosophical question: at what point does resembling a dodo genetically equate to resurrecting the species?īut for Colossal Biosciences, the challenge is worth it. Whether they can fit into a whole new world-300 years later-is hotly debated. Similar to previous projects, resurrecting the iconic bird requires huge advances in genetic engineering, stem cell biology, artificial wombs, and animal husbandry. Founded by Harvard geneticist George Church and tech entrepreneur Ben Lamm in 2021, the company has ongoing projects to recreate the woolly mammoth and the thylacine, or Tasmanian tiger. Recently, a biotech company based in Dallas, Texas called Colossal Biosciences announced an audacious plan to “de-extinct” the dodo. The flightless bird vanished in the seventeenth century, and has since been the poster child for human-caused extinction.īut what if we can bring the iconic bird back? With a massive beak, googly eyes, rotund body, and disproportionately small feathered tail, the dodo is iconic for all the wrong reasons.
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