Tasmanian tiger head soaked for 110 years gives clues to species’ revival

Scientists created the most complete Tasmanian tiger genome ever from a head soaked in solution more than a century ago, providing a nearly complete DNA blueprint, Live Science reported on October 17. This is one of the breakthroughs to revive this extinct animal by the American company Colossal Biosciences.

Hổ Tasmania, hay Thylacine (Thylacinus cynocephalus), is a marsupial that became extinct in 1936 after decades of hunting by humans. They are predators at the top of the food chain, playing an important role in the ecosystem in Tasmania, Australia.

In the new study, a team of experts analyzed a 110-year-old Tasmanian tiger head that was skinned and preserved in ethanol. The specimen’s exceptional preservation allowed the team to reassemble most of the DNA sequence, as well as RNA sequences (molecules with a structure similar to DNA but with only one strand) that show which genes are active. in various tissues when the animal dies.

“You can absolutely get a great genome from old specimens. The genome provides the full blueprint for reviving the Tasmanian tiger, so getting a complete, high-quality genome is a help.” greatly helped that effort,” said Andrew Pask, professor of genetics and developmental biology at the University of Melbourne, Australia.

The newly assembled genome is similar in size to the human genome, consisting of 3 billion nucleotide base pairs – molecules that form the rungs of the DNA ladder. There are still 45 gaps in the DNA sequence that the team of scientists hope to fill in the coming months, as further sequencing is conducted.

The RNA fragments discovered in the immersed head will help the research team find genes that were activated in various tissues when the Tasmanian tiger was alive, helping them determine what the animal can taste, smell and see. , how the brain works. Compared to DNA, RNA is much less stable and easily damaged over time, so preserving RNA could help people understand the biology of the Tasmanian tiger in a way never thought possible, Pask said.

Previously, Colossal Biosciences announced another breakthrough in the Tasmanian tiger revival project that can be applied to the conservation of living species: A group of experts researching assisted reproductive technology (ART) has found a way stimulate ovulation in Sminthopsis crassicaudata – a small mouse-like marsupial and the closest living relative of the Tasmanian tiger. They can create many eggs at the same time for the research team to inject the Tasmanian tiger genome into when the genome is complete. They will also give Sminthopsis crassicaudata surrogacy to develop Tasmanian tiger embryos.

In addition, the research team is also working on an artificial intrauterine device to grow marsupial embryos. The device can now accommodate embryos from early to mid-pregnancy.