The de-extinction concept became popular in the 1990s and since then, scientists have been trying to bring back extinct animals, like the Tasmanian tiger and now the Christmas Island rat.

Scientifically known as Rattus macleari, this species went extinct 119 years ago, most probably due to diseases brought over by European ships that visit their home on Christmas Island located in the Indian Ocean. But modern technology seems to have opened the possibility of bringing this animal back with other extinct animals.

Scientists Reveal Plans of Bringing Back Extinct Christmas Island Rat; But Should They De-Extinct Animals?
(Photo : Pixabay/blende12)
Scientists Reveal Plans of Bringing Back Extinct Christmas Island Rat; But Should They De-Extinct Animals?

De-Extinction of Christmas Island Rats

De-extinction efforts have mainly focused on grand animals, like dinosaurs and mammoths that went extinct around 65 million years ago and 4,000 years ago, respectively. But a new study led by scientists from the University of Copenhagen thought of bringing back the Christmas Island rat.

Science Daily reported that the team plans to use gene-editing, mainly the CRISPR tool, to sequence the genome of an extinct species. However, this is challenging because it is difficult to work with degraded DNA that does not yield all the genetic information needed to reconstruct the extinct animal's full genome.

Instead, they need to sequence the genome of a close relative of the extinct animal. In the Christmas Island rat's case, scientists would need to sequence the Norway brown rat as they share about 95% similar genome with them. Evolutionary geneticist Tom Gilbert from the university added that genome sequencing needed to be compared to a really good modern reference.

After DNA sequencing and matching the extinct animal's genome to its modern reference, the team will identify the parts that do not match and then use CRISPR to edit the DNA of the living species to that of the extinct animal.

However, some key genes related to olfaction are missing from the sequenced Christmas Island rat. That means a resurrected Christmas Island rat would likely have problems with processing odor. Gilbert said that it is still impossible to resurrect a perfect replica of the extinct Christmas Island rat with the current technology.

ALSO READ: Bringing Back Dinosaurs Using Amber-Encased DNA Could Also Bring Back Diseases, Scientist Warns

De-Extinction Technology Could Help Save Endangered Animals

The science of de-extinction is fascinating, but it might come as if scientists have not thought it through with respect to animal welfare, study co-author Ross MacPhee said.

Rather than bringing back long-extinct animals using CRISPR, it might be better to use the technology to make genetic tweaks to vulnerable or endangered living species to help them survive better in the wild, NBC News reported. For example, gene-editing in the endangered California condor could ensure their survival, so de-extinction would not be necessary. It also does not solve the cause of why these animals are at risk.

Wildlife ecology professor Susan Haig from the Oregon State University, who was not part of the study, supports MacPhee's idea of using the CRISPR technology on saving species on the brink of extinction rather than de-extinction efforts.

 RELATED ARTICLE: Scientists to Resurrect the Lost Species of Tasmanian Tiger, Extinct Marsupials Will Bring Balance Back in Tasmania's Ecosystem

Check out more news and information on De-Extinction in Science Times.