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.’

Scientists from Colossal Biosciences say they have made a major breakthrough towards bringing the Tasmanian Tiger back from extinction. This graphic shows how this process will work

Scientists from Colossal Biosciences say they have made a major breakthrough towards bringing the Tasmanian Tiger back from extinction. This graphic shows how this process will work 

The last living Tasmanian Tiger, or Thylacine, died in captivity at Beumaris Zoo (pictured) in 1936

How to ‘de-extinct’ the Tasmanian Tiger

  1. Ancient DNA is recovered from Tasmanian Tiger remains preserved in ethanol.
  2. Scientists reconstruct the Tasmanian Tiger’s genome from the recovered samples.
  3. The genome is compared to that of a fat-tailed dunnart to identify which ‘target genes’ make them different.
  4. These target genes are inserted into fat-tailed dunnart DNA to create hybrid cells.
  5. Hybrid cells are used to create pluripotent stem cells which can be stimulated to become sexual gametes or embryos.
  6. Hybrid Tasmanian Tiger embryos are raised inside an artificial womb or in a fat-tailed dunnart.
  7. A living Tasmanian Tiger is born.

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.’ 

More than 100 years after the last Tasmanian Tiger died, researchers have now recreated the species genome with 99.9 per cent accuracy  

Because Tasmanian Tigers became extinct so recently, there are many well-preserved samples such as hides (pictured)

This is the first time that an ancient genome has been reconstructed with such accuracy and could soon pave the way for genetically engineering the first living Tasmanian Tigers 

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.

Scientists say this is the most complete genome ever created for an extinct animal. The genome only has 45 gaps which will be patched in the coming months 

By comparing these genes to the Tasmanian Tigers closest relative, the fat-tailed dunnart (pictured), the scientists hope to identify the ‘key genes’ which make the Tasmanian Tiger different to other animals 

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 has focussed on recreating the Tasmanian Tiger’s distinctive skull and jaw by identifying several  ‘key genes’ responsible for this distinctive feature 

Colossal Biosciences says its plan is to reintroduce the Tasmanian Tiger into Tasmania so it can re-establish self-sustaining breeding populations 

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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