1.   Clinicians believe they can boost the success rate by combining interferons with ribavirin, a medicine that tricks the virus into making defective copies of itself.

2.   Descendants bred to have two defective copies of the Clock gene, one from each parent, had a daily rhythm four hours longer than normal.

3.   Geneticists in Cambridge, England, have discovered two severely obese children who each carry two defective copies of a gene called Ob.

4.   It is Nathan who teaches Kevin how to sweet-talk a defective copy machine into functioning.

5.   People with one copy can get infected, but they will remain disease-free much longer than people with no defective copies of the gene.

6.   The children inherited defective copies of a gene that makes leptin, a hormone that signals the brain on the amount of fat in the body.

7.   The gene for the allergen will be knocked out by replacing it with a defective copy.

8.   It occurs when a person inherits two defective copies of a gene called CFTR.

9.   Scientists targeted the gene after learning that people who have defective copies of the gene are resistant to HIV infection.