Genome Mapping Offers New Hope for Northern White Rhino Conservation.

In a significant advancement for conservation biology, an international team of scientists has mapped the complete genome of the northern white rhinoceros. This breakthrough offers renewed hope for reviving a species that is functionally extinct, with only two non-reproductive females, Najin and Fatu, remaining under protection at Kenya's Ol Pejeta Conservancy.

The research, published in the Proceedings of the National Academy of Sciences, was led by Jeanne Loring, a stem cell biologist at Scripps Research Institute, in collaboration with experts from the San Diego Zoo Wildlife Alliance and the Max Planck Institute for Molecular Genetics. The team utilized fibroblast cells collected in 1997 from Angalifu, a male northern white rhino who died in 2014, to assemble a high-quality reference genome. Due to stringent regulations on transporting rhino DNA across borders, sequencing was conducted on-site in California using a portable nanopore sequencer brought from Germany.

This reference genome serves as a vital benchmark for evaluating the genetic integrity of induced pluripotent stem cells (iPSCs) derived from northern white rhinos. Loring's team had previously generated iPSCs from the skin cells of nine rhinos, aiming to produce viable eggs and sperm for assisted reproduction. Upon comparison with the reference genome, one iPSC line exhibited a deletion of 30 million base pairs, impacting over 200 genes related to cell cycle regulation and tumor suppression. Such mutations are not unexpected, as iPSCs can accumulate genetic alterations during culture. The reference genome now enables researchers to identify and select stem cell lines with minimal harmful mutations for developing gametes.The Scientist

Desire Lee Dalton, a wildlife conservation geneticist at Teesside University not involved in the study, emphasized the importance of rigorous quality control in stem cell lines before their use in embryo implantation. "This kind of shows that you do have to have this rigorous quality control of these stem cell lines before you implant [embryos made from] them," she noted.

The study also compared the genomes of northern and southern white rhinoceroses, revealing a high degree of similarity. This finding supports the feasibility of using southern white rhinos as surrogate mothers for northern white rhino embryos, a strategy that has been proposed to aid in the species' recovery.

While the research marks a significant step toward conserving the northern white rhino, it also raises broader questions about de-extinction and conservation priorities. Dalton pointed out the ongoing debate in the scientific community regarding the focus on reviving extinct species versus protecting those currently endangered. "If they do bring [northern white rhinos] back, what are we going to change now that we didn't change back then that caused them to be extinct?" she questioned.

Loring clarified that the team's goal is not de-extinction in the traditional sense but rather preventing the complete loss of a species on the brink. "We are not going to try to de-extinct anything," she stated. "This is not the way that we would bring back a T. rex or a woolly mammoth or a dire wolf." Co-author Franz-Josef Müller expressed hope that their collaborative approach would inspire further solutions in conservation efforts.

This genomic mapping represents a pivotal advancement in the application of stem cell technology for wildlife conservation, offering a potential lifeline for the northern white rhinoceros and setting a precedent for similar initiatives aimed at preserving endangered species.

Source:https://www.the-scientist.com/rhino-genome-mapped-in-hopes-of-species-rescue-73047

This is non-financial/medical advice and made using AI so could be wrong.