With global warming and environmental destruction, many animal species are at risk of extinction in the near future. In this context, japanese scientists have succeeded in clone a mouse from freeze-dried adult cells. These cells can be easily stored for long periodsand above all, the cloned mice have could have descendants.
Freezing preservation has been used for some time. Storage locations are called “frozen zoos” and they serve to store sperm, eggs, or other types of tissue at cryogenic temperatures. This technique can potentially revive extinct species or populations. However, those frozen zoos need a lot of energy. They are therefore very expensive and are not immune to power outages or natural disasters.
Japanese scientists have thus begun to study the possibility of using freeze-dried cells, i.e. cells from which water has been removed. The cells are kept in a more stable form and do not require extreme temperatures. We have already succeeded in preserving sperm with this technique, but according to experts, it is not easy to obtain healthy sperm from certain animals.
Cloning as an alternative
The researchers behind this new study have thus developed a method for cloning animals from freeze-dried somatic cells. This category includes all cells that are not sperm or eggs.
According to the scientists, the results were promising. Freeze-dried somatic cells could be stored for a period of up to 9 months at a more manageable temperature of -30°C. Also, the researchers were able to produce clones from these cells.
After rehydration, the nuclei of these cells were removed and placed in an oocyte to obtain a blastocyst. The blastocysts were then used to grow new embryonic stem cell lines which served to create embryos. The latter were finally placed in carrier mice which gave birth to cloned mice.
When the baby mice reached adulthood, they were able to have offspring. It means that their fertility remained intactand the technique is therefore suitable if one seeks to restore an extinct species.
Even though this method seems ideal, scientists have still encountered some problems. Somatic cells die during the freeze-drying process. Hence, there is more DNA damage than with other methods. After going through all the stages of the technique, the total success ratel of cloning a mouse from freeze-dried cells is only 0.02%.
Despite these problems, the researchers indicate that this technique is viable. Its stability and low cost are its main advantages.