**Colossal Biosciences Nears Breakthrough in Tasmanian Tiger De-Extinction**

Colossal Biosciences, renowned for its attempts to genetically engineer proxies for various iconic extinct species, has announced significant progress in its efforts to bring back the thylacine, commonly known as the Tasmanian tiger. This carnivorous marsupial, which was declared extinct in 1936 due to extensive hunting and habitat loss, might soon have a proxy species that closely resembles it.

In a monumental update, Colossal reported that the thylacine genome it reconstructed is now approximately 99.9% complete, with only 45 gaps remaining. These gaps are expected to be closed through further sequencing in the upcoming months. This progress follows a breakthrough last year when researchers, unaffiliated with Colossal, successfully recovered RNA from a thylacine for the first time, earning them notable recognition at the Gizmodo Science Fair.

Colossal stated that they managed to isolate long strands of RNA from a 110-year-old thylacine specimen preserved in ethanol. Back in 2022, the company had committed to the ambitious goal of "de-extincting" the thylacine. This process, due to the absence of living thylacines, involves creating proxy species that, although not 100% identical, will look and function much like the original animals in their natural habitats.

The thylacine, often referred to by its nicknames Tasmanian tiger and marsupial wolf, was the only member of its genus, Thylacinus cynocephalus, and shared no close relation with actual tigers or wolves. To achieve their goal, Colossal plans to genetically edit the cells of the fat-tailed dunnart, the thylacine's closest living relative, to recreate the nearest possible genetic match to the extinct species.

However, even with the genome nearing completion, some genetic parts might be irretrievably lost to time. Similar challenges were faced by other researchers who studied the extinct Christmas Island rat as a case study for de-extinction. Among them was a current member of Colossal’s advisory board who previously voiced concerns over the ethical and financial aspects of such projects, suggesting that resources could be better spent on conserving existing species.

Despite these ethical debates, Colossal continues to push boundaries in gene editing. Earlier this year, Gizmodo had an insightful conversation with Beth Shapiro, the company's chief science officer, about the various challenges and timelines associated with their de-extinction projects. Notably, the company had recently made a breakthrough by engineering elephant stem cells, marking a step forward in their endeavor to create mammoth-like, cold-resistant Asian elephants.

Colossal's efforts are not limited to ancient species alone. They have also made strides in improving the genetic resilience of extant species like the northern quoll against toxins from the invasive cane toad. By altering a single base in the quoll's genome, they significantly boosted its resistance to this lethal toxin, showcasing the potential advantages of genetic intervention.

As Colossal advances its multiple projects, the world watches closely to see if their work in gene editing heralds a new era of scientific achievement or repeats the mistakes of past environmental interventions.