41.   T cells with the defective gene start to grow and then die.

42.   The defective gene has been identified, which gives researchers hope.

43.   The disease develops when a child inherits two copies of a defective gene, one from each parent.

44.   The flawed papers involved laboratory research on the role of a defective gene in producing acute leukemia.

45.   The mutant mouse had a basic daily rhythm about an hour longer than normal mice, caused by a single defective gene, which Takahashi named the Clock gene.

46.   The reason is that women can often compensate for a defective X chromosome gene if the counterpart gene on their second X chromosome is in working order.

47.   The same method can be applied to searching for defective genes that contribute to disease.

48.   The shot also worked for mice without the defective gene, although they lost less weight.

49.   The shot, containing a protein, also worked for mice without the defective gene, although they lost less weight.

50.   This protein is missing in individuals who have inherited two copies of the defective gene, one from the mother, one from the father.