SCID Therapy

Basically scientists identified a functional gene from a donor and cloned it. Then they inserted the cloned gene into a harmless retrovirus. At the same time, they removed some of her white blood cells and cultured them in the laboratory. Then they let the retrovirus enter the cultured cells. Once they were sure that the cultured cells had integrated the new gene, they injected the engineered cells back into her where the virus entered other cells and incorporated the functional gene in her genome. The new gene then began to manufacture the enzyme that breaks down the adenosine. You can learn more about the various techniques used to work with DNA at the site indicated below. But first a few questions:

• How do you clone a gene?
• Why would they use a retrovirus as a vector to introduce a new gene into the young woman?
• Why did the scientists use white blood cells?
• How could the scientists prove that the cultured white blood cells had incorporated the new gene?
• If this young woman were to become pregnant, will the acquired enzyme be present in her child?
• Are there other ways a gene can be given to a patient?
• Just how safe is gene therapy?