Northern white rhinoceros: New hope for IVF rescue

A new study is hoping to save one of the last animals of its kind.

Victim of poaching, the northern white rhinoceros population was reduced to two females, both of which were unable to reproduce.

DNA evidence shows that the rhinoceros is more closely related than was thought to its southern white cousin.

According to scientists, the creation of rhinoceros hybrids with the help of IVF will likely have positive results, although this option is considered a last resort.

The white rhinoceros is divided into two divided populations living in northern and southern Africa about one million years ago.

However, an in-depth analysis of live rhinoceros DNA and museum specimens shows that northern and southern populations mix and sometimes reproduce after this date, perhaps 14,000 years ago.

"Although they started to diverge a million years ago, we show that they exchanged genes during this period, perhaps as recently as the last ice age, when the African savannah developed and allowed to reconnect the two populations, "continued Dr. Dr. Michael Bruford of Cardiff University told BBC News.

"So, if they exchanged genes recently, that may imply that they could do it now."

Cross-breeding using assisted reproductive technologies could potentially save the northern white rhinoceros from its current situation, he said.

How many white rhinos remain in the north and south?

The Northern White Rhino was once common throughout the north of the African continent, including Uganda, South Sudan, DRC and Chad.

Illegal hunting to satisfy demand for rhinoceros horn has caused a rapid decline in nature. The rhinoceros subspecies was declared extinct in the wild in 2008.

Earlier this year, Sudan, the last northern white rhino, died at 45 years old.

There are two women left – her daughter and granddaughter, who live at Ol Pejeta Conservancy in Kenya, where they are monitored at all times. However, both have health problems of their own and can not reproduce naturally.

The southern white rhino is found in southern Africa, including South Africa, Namibia and Zimbabwe.

The number of inhabitants dropped to a few hundred individuals about a century ago, but conservation efforts have allowed recovery. There are around 20,000 in protected areas and private game reserves.

What would it take to save the northern white rhino?

The survival of the northern white rhinoceros seems bleak and relies on highly controversial conservation efforts, which involve IVF and cloning.

There is still an invaluable supply of frozen white rhino sperm from the North, but nature's supporters are divided on how they should be used.

In July, a team took eggs from southern female rhinos – about 20,000 in the wild – and fertilized them with frozen sperm from a northern white rhinoceros to create hybrid embryos.

The new study suggests that this type of approach could pay off, as both rhinos are closer genetically than previously thought.

"We think it improves the chances," said Professor Bruford. "It's hard to predict what could happen if we cross the two subspecies, but given the current options for the Northern White Rhino, it becomes a more viable option if other approaches fail."

Other options include the use of frozen tissue from a larger pool of northern white rhinos to generate stem cells that can turn into ova and sperm.

This would avoid diluting the gene pool, but is more difficult to achieve.

The research, conducted by scientists from the United Kingdom, South Africa, the Czech Republic, Austria, Germany and the United States, is published in the journal Proceedings of the Royal Society of London B.

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