It’s becoming increasingly difficult to keep up with technological and scientific advances that seem to be leaping forward at an accelerated pace. One of the latest animal cloning breakthroughs came from Japanese researchers at the Riken BioResource Centre in Tsukuba, Japan. (1)

According to an article in the June 26th edition of the Journal of Biology of Reproduction (5), Japanese scientists created a cloned mouse from a single drop of blood. Some scientists have commented that it’s just one small step in improving the animal cloning process while others believe it could be an important breakthrough.

The Japanese team took a drop of blood from a female mouse’s tail and created a clone. The research center announced that the cloned female mouse lived a full lifespan and reproduced offspring like any other normal mouse.

The process of animal cloning follows the method used for creating Dolly, the first sheep to successfully be cloned in 1996. This certainly isn’t the first mouse to ever be cloned. Previous clones have been created from donor cells taken from lymph nodes, liver and bone marrow.

There have been numerous other clones created using the Dolly technique. In fact, scientists at a similar institute most recently created over 600 “genetic copies of one mouse”. (2)

Unlike those clones, the Riken mouse clone method didn’t use a white blood cell taken from tissue, but from circulating blood drawn from the mouse’s tail. The other method required the death of the original animal in order to obtain the necessary genetic material that typically comes from tissue.

The objective of the Japanese team was to see if they could accomplish the same cloning results by using blood samples or more aptly, cell suspension (unattached cells) instead of the tissue (attached cells).

The method they used was non-invasive and the original mouse remained unaffected and alive after the procedure. The mouse clone is the first of its kind and clearly demonstrates that cloning can be achieved by using peripheral blood cells instead of tissue cells.









Animal Cloning

The science for animal cloning is known as SCNT (Somatic Cell Nuclear Transfer). SCNT technology uses a single cell to clone an animal.

For the cloned mouse, the cell used to create the clone was freshly collected “peripheral” blood obtained from the tail. This “noninvasive” method of collecting blood is considered more desirable for nuclear transfer, but had never been done.

Once collected, scientists then prepared the nucleated cell (leukocyte) suspension by lysing (dissolving) the red blood cells.

A nucleated cell suspension simply means that the cell used had a nucleus and was the type of cell that lived in the blood (suspended) and wasn’t the type of cell that’s attached as those found in tissue.

A leukocyte is a white blood cell as opposed to a red blood cell. Once the red cells were dissolved, the white cells were all that remained and the scientists then selected the leukocyte nuclei randomly.

The cell was then transferred into an egg cell that had the nuclear DNA removed. That enabled the new cell to essentially replace the original nuclear DNA, meaning that the mouse grew from the original mouse’s genetic material and thus produced a clone.

Since the cloned embryo contained the exact genes of the donor, it grew into a duplicate of the original. (2)