Mice cloned for the first time in Spain

Washington, June 13 (ANI): Making one of the biggest breakthroughs in cloning, researchers at the Department of Cell Biology, Physiology and Immunology at Universitat Autonoma de Barcelona (UAB) have become the first one to clone mice in Spain.

The scientists created Cloe, Cleo and Clona-the three female brown-coloured mice that were born respectively on 12 May, 3 June and 10 June.

Using nuclear transfer techniques, the scientists collected mature oocytes, removed their chromosomes, and substituted them for the nucleus of an adult somatic cell.

The cloning of mice is part of a research meant to study new ways to improve the efficiency of the cloning process.

The researchers, who were in charge of cloning the mice, have said that all three of them are being suckled with other non-clones and their growth parameters are within normal range.

For cloning, the researchers collected oocytes and surrounding cumulus cells from several female mice.

They then extracted chromosomes from each of the oocytes and substituted it with a cell from the cumulus by cytoplasm injection.After reconstructing the oocytes, the researchers reactivated them by simulating the stimuli occurring during fecundation so as to induce embryonic development.

The cloned embryos were later transferred to receptor females.

The mice thus obtained were not only the first of their species cloned in Spain, but are the first animals to survive at birth and develop correctly.

The cloning of the mice forms part of a research aimed at discovering new ways of improving the efficiency of the cloning process.

The researchers are now studying whether the use of valproic acid could contribute to an increase in the success rate of nuclear transfer cloning, currently situated at approximately 1 percent for mice using standard procedures.

Valproic acid is an inhibitor of the enzyme histone deacetylase, located at the cell nucleus where the DNA is found.

The studies at UAB can not only be applied to reproductive cloning of animal models, but can also be used for the reprogramming of cells for therapeutic aims. (ANI)