Three live dire wolf pups have been born using reconstructed DNA. The extinct species had last roamed North America around 12,500 years ago. The milestone was reached by a Dallas-based biotech firm that focuses on genetic conservation. Ancient DNA samples from fossilised remains were analysed. Modern gene-editing tools were used to mimic key characteristics of the extinct predator. These pups were brought to life by implanting modified embryos into domestic dog surrogates. The young wolves have been named Romulus, Remus and Khaleesi.

Ancient DNA edited in lab to recreate species

According to a study shared by Colossal Biosciences, DNA samples had been collected from two ancient dire wolf fossils. One was a 13,000-year-old tooth, while the other was a 72,000-year-old skull fragment. These fragments were compared to modern wolf relatives and grey wolves were chosen for DNA alteration because of their evolutionary proximity. Gene sequences that were found only in dire wolves were isolated. These were introduced into the DNA of grey wolves through targeted editing.

Cloning technique used to implant embryos

The altered genetic material was inserted into grey wolf egg cells after removing their original nuclei. These prepared cells were placed inside domestic dogs. Each surrogate received multiple embryos. Interestingly, only one embryo survived in each of the first two dogs. Both gave birth by caesarean section, while the third pup was born in a second round of implantation.

Physical traits match fossil record

The new pups have been observed to develop features consistent with known dire wolf fossils. Thick white coats, larger teeth and body structure have been reported. These results came from identifying changes in 14 genes. The gene edits were introduced using CRISPR technology.

The same company had previously cloned red wolves. The team had also created “woolly mice” as part of a mammoth revival effort. The successful dire wolf birth marks a new phase in gene-driven species restoration.