3 Cloned Mice, From Ordinary Cells

Scientists in Hawaii have cloned a trio of identical mice using ordinary cells rather than DNA extracted from the female reproductive system. This time, the cloned critters were male.

The clones grew using genetic material extracted from tail cells of adult male mice, but only one grew to adulthood, according to a study in the June issue of the journal Nature Genetics.

Researchers said their experiment demonstrates that cloning can be accomplished with the genetic material contained in the nucleus of somatic cells, or ordinary cells found throughout the body.

Previously, most cloning experiments, ranging from mice to sheep, used DNA extracted from female reproductive cells.

Scientists said somatic cells, such as tail cells, are more plentiful, and large amounts of their genetic material could be frozen and stored for later use.

That would help to make cloning a more efficient procedure in agriculture and commercial laboratory operations. It also might help conservationists rescue endangered species by enabling them to stockpile more of the genes of rare animals for cloning.

Other scientists said the cloning of male mice from tail cells was not a remarkable achievement. For example, bulls have been cloned using DNA from ear samples.

But the problems the Hawaii team encountered with mice eventually could improve the cloning of a variety of animals, they said.