Japanese researchers for the first time cloned a mouse from a freeze-dried skin cell. The technology can be used in nature conservation to restore endangered species. This is reported by The Guardian.
The discovery will allow countries to store animal skin cells as an “insurance policy” against their extinction. If a certain species is on the verge of extinction, clones can be created from the saved cells, which will increase its genetic diversity.
Many endangered species suffer from inbreeding (mating of related individuals), which carries risks of congenital diseases. Also, the loss of genetic diversity makes animals vulnerable to other threats, such as disease, which increases the pressure on a species on the brink of extinction.
The technology of freezing dried cells is simpler and cheaper than storing cells in liquid nitrogen. Another technology to restore the species could be the use of freeze-dried sperm, but it cannot be obtained from all animals.
“Developing countries will be able to store their own valuable genetic resources in their own countries. Also, even in endangered species where only males survive, this technology can be used to create females to revive the species,” says the professor from the University of Yamanashi in Japan, who led the project.
In the new work, scientists freeze-dried skin cells from the tails of mice and stored them for nine months before trying to clone them. The drying and freezing process killed the cells, but they were still viable for making embryos.
The first cloned mouse was named Dorami. After her, 74 more animals were created. To test the fertility of the clones, 9 females and 3 males were mated with normal mice. All females had offspring.
Despite the significance of the discovery, the transformation of cells into living organisms was not very effective. Scientists achieved success in creating healthy mice in only 0.2%-5.4%. Drying and freezing damaged the DNA in the cells. Some also lost the Y chromosome, causing female mice to form from male cells. However, the discovery may still help save species that only have males left.
The research was published in the journal Nature Communications.