Reinserting the altered cell could cure the disease.

The hope was that the genetically altered cells would produce the missing blood factor and cure the children of their disease.

These genetically altered cells are put back into the animal from which they came.

Some of these slightly altered cells might produce specific metabolites or antibodies that could be detected early.

"It's the only way we can make a thorough study of the altered cells of your bodies."

Then start the cloning process by adding that altered cell to an egg.

That gene makes the altered cells resistant to the anticancer drug methotrexate.

After receiving the altered cells, patients will be treated with methotrexate.

This is because genetically altered cells end up peppered throughout the animal.

In a report in December, the altered cells were said to be flourishing, with no sign of cancerous growth.