RNA from extinct Tasmanian tiger recovered for the first time

The Tasmanian tiger, a dog-sized striped carnivorous marsupial also called the thylacine, was an apex predator that hunted kangaroos and other prey and once roamed the Australian mainland and adjacent islands. Because of humans, the species is extinct.

But that doesn’t mean scientists have stopped learning about the subject.

For the first time, researchers announced, this Tuesday (19), that they recovered RNA — genetic material present in all living cells that has structural similarities to DNA — from the dissected skin and muscle of a Tasmanian tiger that has been stored since 1891, in a museum in Stockholm.

In recent years, scientists have extracted DNA from ancient animals and plants, some of them more than 2 million years old. But this study marked the first time that RNA — which is much less stable than DNA — was recovered from an extinct species.

Although not the focus of this research, the ability to extract, sequence and analyze ancient RNA could boost other scientists’ efforts to recreate extinct species. Recovering RNA from ancient viruses could also help decipher the cause of previous pandemics.

What is the difference between DNA and RNA?

DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) — biomolecular cousins ​​— are fundamental molecules in cell biology.

DNA is a double-stranded molecule that contains the genetic code of an organism, carrying the genes that give rise to all living beings.

RNA is a single-stranded molecule that carries the genetic information it receives from DNA, putting that information into practice. RNA synthesizes the set of proteins that an organism needs to live and works to regulate cellular metabolism.

“RNA sequencing gives insight into the true biology and regulation of metabolism that took place in the cells and tissues of Tasmanian tigers before they became extinct,” said geneticist and bioinformatician Emilio Mármol Sánchez of the Center for Paleogenetics and SciLifeLab in Sweden, author leader of the study published in the journal Genome Research.

“If we want to understand extinct species, we need to understand what genetic complements they have and also what the genes were doing and which were active,” said geneticist and study co-author Marc Friedländer of Stockholm University and SciLifeLab.