Mice Using Freeze-Dried Cells Cloned Using a Technique That Could Soon Help Animal Extinctions

Japanese researchers have recently produced cloned mice successfully using freeze-dried cells in an approach they believe could someday help conserve species and deal with challenges with the present biobanking methods.

The United Nations has cautioned that extinctions are revving worldwide, and at least one million species could vanish due to human-induced effects such as climate change, a Phys.org report specified.

Facilities have sprung up worldwide to preserve specimens from endangered species to stop future cloning.

Such samples are generally cryopreserved, using liquid nitrogen, or kept at low temperatures, which can be expensive and susceptible to power outages.

Freeze-Drying Somatic Cells

Typically, they involve egg and sperm cells, which can be a struggle or impossible in terms of harvest from infertile or old animals.

Researchers at the University of Yamanashi in Japan wanted to find out if they could deal with such challenges by freeze-drying somatic cells, any cell that is neither an egg nor sperm cell and trying to produce clones.

The scientists experimented with two types of mice cells and discovered that while freeze-drying killed them and resulted in substantial DNA damage, they could still generate cloned blastocysts, a ball of cells developing into an embryo.

The researchers extracted the stem cell lines used to produce 75 clone mice. One of the mice survived for one year and nine months, and the team was able to mate female and male clones with natural-born partners successfully and produced normal pups.

Mice Clones

The cloned mice produced fewer offspring than would have been expected from the natural-born ones, and one of the stem cell lines developed from male cells produced only female mice clones.

According to Professor Teruhiko Wakayama, from the University of Yamanashi's Faculty of Life and Environmental Sciences, who helped lead the research published in the Nature Communications journal, "improvement should be difficult.

The professor also said they believe that in the future, they will be able to reduce abnormalities and increase birth by looking for freeze-drying protectant agents and enhancing drying methods.

Some Disadvantages

While this is a promising technique, There are some other drawbacks, according to a similar Rfi report. The success rate of cloning mice from cells stored in liquid nitrogen, or an at very low temperatures from two to five percent, while the freeze-dried method is only 0.02 percent.

Wakayama explained that the technique is still in its early stages, comparing it to the research that produced the famous sheep clone, "Dolly," a single success after over 200 attempts.

The professor also said the most essential thing is that cloned mice have been produced from freeze-dried somatic cells, and a breakthrough has been achieved in this field.

Senior research fellow Simon Clulow from the University of Canberra's Centre for Conservation Ecology and Genomics added while this method is unlikely to replace "cryopreservation," it denotes a "very exciting advance" for researchers interested in biobanking threatened global diversity.

'Cryopreservation'

Clulow, who was not part of the study, continued explaining that it can be a struggle, not to mention, expensive, to work up cryopreservation protocols, and so substitutes, particularly those that are cheaper and robust, are very much welcome.

The study, a similar Tabbed News report specified, stored the freeze-dried cells at minus 30 degrees Celsius, but the researchers have previously shown freeze-dried mouse sperm can endure at least one year at room temperature.

This approach could ultimately enable genetic resources from all over the world to be stored cheaply and safely, said Wakayama.

Related information about freeze-dried mice is shown on Discover Magazine's YouTube video below:

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