Two weeks ago, DNA Science covered the plight of the northern white rhino, suggesting assisted reproductive technologies (ARTs) that might preserve the genomes of the nearly-extinct subspecies. A paper published last week, in Nature Communications, reports creating embryos by injecting northern white rhino sperm nuclei into southern white rhino oocytes (unfertilized eggs).
The hybrid rhino embryos developed to a key early stage, the hollowed-ball blastocyst. If they can survive transfer to surrogate southern rhinos and continue developing, it would demonstrate that at least one route to salvaging the subspecies may be possible. But it might not be enough.
The blastocysts are “the first in vitro produced rhinoceros embryos ever,” said co-author Thomas Hildebrandt, of the German Leibniz Institute for Zoo and Wildlife Research. The northern white rhino population is down to just two infertile females (Najin and her daughter Fatu). The last male, Sudan, died in March. The southern subspecies is some 21,000 animals strong. Yet ironically, the genomes of northern animals, albeit based on a handful of samples, are more diverse.
The hybrid embryos, harboring one southern and one northern genome, are halfway to the goal of re-establishing a founding population of the dwindling subspecies. Mating the hybrids for several generations, serially selecting offspring with the highest percentages of northern DNA, could approach reconstituting the genome of the northern white rhinoceros, given time and luck. This is classical genetics sprung from an assisted reproductive technology.
Continue reading at DNA Science, my blog for Public Library of Science. Read More
The hybrid rhino embryos developed to a key early stage, the hollowed-ball blastocyst. If they can survive transfer to surrogate southern rhinos and continue developing, it would demonstrate that at least one route to salvaging the subspecies may be possible. But it might not be enough.
The blastocysts are “the first in vitro produced rhinoceros embryos ever,” said co-author Thomas Hildebrandt, of the German Leibniz Institute for Zoo and Wildlife Research. The northern white rhino population is down to just two infertile females (Najin and her daughter Fatu). The last male, Sudan, died in March. The southern subspecies is some 21,000 animals strong. Yet ironically, the genomes of northern animals, albeit based on a handful of samples, are more diverse.
The hybrid embryos, harboring one southern and one northern genome, are halfway to the goal of re-establishing a founding population of the dwindling subspecies. Mating the hybrids for several generations, serially selecting offspring with the highest percentages of northern DNA, could approach reconstituting the genome of the northern white rhinoceros, given time and luck. This is classical genetics sprung from an assisted reproductive technology.
Continue reading at DNA Science, my blog for Public Library of Science. Read More
