Send in the clones - 50 mice cloned from 1 original - Brief Article

Science World, Oct 19, 1998 by Maia Weinstock

Not long ago, Dolly, the world's first cloned sheep, had the spotlight all to herself. Then along came Gene, the first cloned calf (see SW 11/3/97). Now, center stage for clones (near-exact genetic duplicates) is a mob scene. Researchers at the University of Hawaii (UH) say they have created more than 50 mice clones, each one almost genetically identical to the next.

The latest mass creation was made possible by a new and improved cloning technique, called the Honolulu Technique, developed by UH researcher Teruhiko Wakayama. But although cloning techniques differ, the end result is the same: duplicates that are as similar as identical twins.

First, UH researchers selected a single adult cell from a female mouse to be cloned. The cell is a cumulus cell, which surrounds developing eggs in female mice. Using a tiny straw-like glass instrument called a micropipette, researchers sucked out the cell's nucleus, the part that houses genetic information. Next, they inserted the nucleus directly into an empty egg cell from another female mouse. No male sperm was used in the process.

After six hours, researchers added chemicals to induce fetal development. (By contrast, Dolly's egg was electrically shocked to induce development). Finally, the embryo, or developing egg, was implanted into a third "surrogate" mouse. surrogate mom carries a fetus, but has no genetic relationship to her baby.) Twenty days later a clone was born.

After the first batch of mice was born, Tony Perry, a researcher in the study, and his colleagues tested to see what would happen if they cloned a clone. Surprisingly, clones of clones seemed to be just as healthy as the clones of normal mice.

Why clone animals in the first place? The main reason is to develop organs that could be used for transplants in humans. In fact, the creators of Dolly and the UH mice are already working together to clone pigs for the animals' transplantable organs.