Embryo Breakthrough Could Save Nearly Extinct White Rhinos

  • Embryo Breakthrough Could Save Nearly Extinct White Rhinos

Embryo Breakthrough Could Save Nearly Extinct White Rhinos

However, the southern white rhino has been considered one of the hallmark conservation success stories, with a population estimated by some groups to now exceed 20,000 individuals.

A team of global scientists has performed the first ever in vitro fertilisation for a rhinoceros and researchers say frozen sperm could be used to create new embryos.

However, even if the implantation of clean embryos in future will result in the appearance of healthy offspring, the Northern white Rhino is facing another big problem: lack of genetic diversity required for healthy populations. Additionally, the global team established stem cell lines from blastocysts of the SWR with typical features of embryonic stem cells. The desperate logic of mixing subspecies and applying assisted reproduction technology is also being discussed regarding the Sumatran rhino. Southern white rhinos are closely related to northern white rhinos and so their genetic pairing is ideal for potential IFV.

"Our results indicate that ART (assisted reproduction techniques) could be a viable strategy to rescue genes from the iconic, nearly extinct, northern white rhinoceros", the team wrote in the journal Nature Communications.

Earlier this year, the rather sad news was announced that the last male northern white rhino had died.

Najin and her daughter Fatu are the only remaining female northern white rhinos, who are confined at the conservancy. These genes might benefit the southern white rhinos that move into their relatives' former habitats, or confer advantages to living rhinos during disease outbreaks.

These researchers think so, and others around the world who have been involved in efforts to save the northern white rhino say it is an important step.

"It is important that we learn from the plight of the northern white rhino and we make sure what happened to it does not happen to other endangered species". They also envisioned to bringing already extinct species back from the dead.

This is why they have the ambitious plan to extract the eggs from living NWR females first and then breed the hybrid white rhinos. The team has tissue samples from northern white rhinos. Of these 13 eggs, four developed into hybrid embryos.

"The SWR and SWR x NWR hybrid embryos created by the team led by Professor Cesare Galli, who's the senior author from the Italian reproductive laboratory Avantea, were very high quality and the stem cells created from two of them expressed all of the genes you'd expect them to express", says Professor Renfree. The embryonic stem cell lines obtained in this study have now been transferred to Dr Diecke's lab, as they will serve as a blueprint to differentiate iPS cells into germ cells and eventually gametes.

"These are the first in vitro produced rhinoceros embryos ever".

Two of the blastocysts have now been cryopreserved and these frozen embryos could soon be implanted into a southern white rhino surrogate to produce a baby hybrid rhino; preserving at least some of the unique genetics of its northern cousin.

Details of their experiment are published in the journal Nature Communications on July 4.

Now that scientists know they can reliably collect eggs from female white rhinos, and that northern white rhino sperm can fertilize a white rhino egg in the lab, the next step is to go to Kenya and harvest eggs from the last two northern white rhinos on Earth.

If successful, this could see a calf born within three years in Kenya - and even more at Longleat Safari Park in Wiltshire.

In vitro fertilization is the last hope to save the northern white rhinos, a subspecies of white rhinos, since the last male died in March.