Gene therapy may be in its infancy, but great hopes for its potential to treat everything from cancer to Alzheimer’s to heart disease are forcing it to grow up fast. After two decades of lab research, gene treatments are increasingly making their way into human clinical trials. The bulk of research so far has focused on getting a gene to its destination and coaxing it to turn on once inside a cell. On their own, genes can’t pass through cell membranes, and much effort has been spent to trick cells into accepting foreign genes. The most efficient couriers are so-called viral vectors: viruses whose genomes have been swapped out for therapeutic genes. Like Trojan horses, they slip genes into target cells undetected. But as scientists are learning, there is no safe way to hijack a virus. The vectors sometimes trigger immune reactions. And once the genes are inside a cell, there is no way to be sure they will function as intended. Case in point: a Paris gene therapy trial to treat SCIDs, or the “bubble boy disease,” restored immune function in nine of 10 patients. But it was later revealed that two of them had developed leukemia.
【Group】What does the word “trigger” mean in the passage?
(A) Activate (B) Shoot (C) Turn off (D) Plug
31. My son’s decision hurt, but I deserved it—not simply because it highlighted my thoughtless reaction to his gesture, but because it triggered memories of another little boy.
Which of the following statements is true?
(A) My memories of my son were really hurtful.
(B) My son did something ungrateful to me and it served me right.
(C) No one was aware of my thoughtless response to my son’s goodwill.
(D) My son got hurt because I pulled the trigger accidentally.