It is one of the world’s most distinctive extinct animals and can be found on Tasmania‘s coat of arms, government logo, and even on the state’s licence plates.
Now, it might not be long before real Tasmanian Tigers – also known as thylacines – are seen once again.
Colossal Biosciences, a US-based startup, has taken a major step towards resurrecting the lost species.
The team has successfully reconstructed the animal’s genome with 99.99 per cent accuracy.
Ben Lamm, CEO of Colossal Biosciences told MailOnline: ‘We have not publicly set a date for the thylacine but as our announcement today shows, the team is making significant progress across many of the core research areas.’
In order to bring the Tasmanian Tiger back from extinction, scientists first need to reconstruct the species’ lost genome.
In a major step towards this goal, Colossal Biosciences has today announced the creation of the most complete Tasmanian Tiger genome ever made.
Using samples taken from an exceptionally well-preserved specimen, researchers were able to assemble the 3 billion bases within the Tasmanian Tiger genome with 99.9 per cent accuracy.
The genome now only has 45 gaps, which Colossal says will be closed within the coming months.
Since DNA is exceptionally fragile, it normally breaks down quickly after the organism dies.
However, since the last Tasmanian Tiger died less than 100 years ago, there are a number of extremely well-preserved specimens in museums across the world.
This allowed the researchers at Colossal Biosciences to extract long sections of DNA from the tissues of a 110-year-old Tasmanian Tiger head which had been skinned and placed in ethanol.
Dr Beth Shapiro, Colossal’s chief science officer, says: ‘The thylacine samples used for our new reference genome are among the best preserved ancient specimens my team has worked with.
‘It’s rare to have a sample that allows you to push the envelope in ancient DNA methods to such an extent.’
Dr Andre Pask, a member of Colossal’s Scientific Advisory Board and head of the Thylacine Integrated Genomic Restoration Research Laboratory at the University of Melbourne, said: ‘This exceptional sample provides a fantastic opportunity for us to understand gene expression in thylacines.
‘With this new resource in hand we will be able to determine what a thylacine could taste, what it could smell, what kind of vision it had and even how its brain functioned!’
Now that the Tasmanian Tiger genome has been reconstructed, the de-extinction process will begin by comparing this with their closest living relative, the fat-tailed dunnart.
Since their genomes are so similar, scientists hope to identify the ‘key genes’ which determine whether an organism becomes more like a Tasmanian Tiger or more like a dunnart.
Using gene editing techniques like CRISPR, scientists can cut and paste these key genes into the genome of the fat-tailed dunnart to create hybrid DNA.
Cells from the fat-tailed-dunnart are then chemically coaxed into becoming pluripotent stem cells – a type of cell which can transform into any type of tissue.
By inserting the hybrid DNA into these cells, scientists can grow eggs, sperm, or even embryos with the genetic potential to become Tasmanian Tigers.
Embryos or fertilised eggs can then be inserted into a surrogate fat-tailed dunnart mother who will carry the hybrid to term.
Once the embryo has developed and been born, the resulting animal should be identical to the once-extinct Tasmanian Tiger.
Colossal Biosciences says it has already started using the reconstructed genome to begin isolating some critical key genes.
For example, Colossal Biosciences has been focusing on the Tasmanian Tiger’s distinctive skull and jaw shape.
By comparing the reconstructed genome with the genomes of wolves and dogs, the scientists identified two sets of genes they are calling Thylacine Wolf Accelerated Regions (TWARs).
When three sections of the mouse genome were swapped out for TWARs, researchers found that they could change the shape of mice’s heads to be more like a Tasmanian tiger.
Sara Ord, director of species restoration at Colossal Biosciences, says: ‘This is crucial evidence of the power of Colossal’s approach and an important step toward Thylacine de-extinction.’
Colossal Biosciences is yet to say when the first Tasmanian Tigers will be born, but the company hints that it may be coming soon.
Speaking to MailOnline earlier this month, Mr Lamm said that the Tasmanian Tiger project could finish before the first Mammoths are born in 2028.
Although it is not yet confirmed, that could mean Tasmanian Tigers will be back from extinction within the next four years.
The company is so confident in hitting this goal that it is already planning for what to do with its newly born Tasmanian Tigers.
Mr Lamm says: ‘Colossal’s goal is for complete rewilding of the thylacine back into the ecosystem with a diverse enough population that the species will not only survive but thrive again in the wild.
‘Colossal in collaboration with conservation groups, ecologists, indigenous people representation, university, local representation among others is working to identify potential rewilding sites.’
Mr Lamm adds that several ecological surveys are already underway and that potential sites should be announced ‘in the next year or two’.
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