Section B
        Genetic engineering on a planetary used to be the stuff of science fiction dreams andsometimes nightmares. But now the potential has arrived. For the first time, discussions aboutquickly transforming entire ecosystems on a large scale are no longer hypothetical. Scientistsfrom the University of California, San Diego and the University of California, Irvineannounced that they had genetically engineered a breed of mosquito that not only blocksinfection by malaria parasites, but can quickly spread its antimalarial genes throughout itsspecies.__(36)__ . Since malaria kills hundreds of thousands of people annually, the potentialbenefit is obvious. __(37)_.
         There's a vast potential to easily introduce desirable changes in other wild species, alongwith farm animals and cultivated plant__(38)__. And the list is endless.But worries about pitfalls and mistakes are also widespread. Lessons from previousecological disruptions resonate in the minds of scientists and bioethicists. Unintended havocis sometimes caused when people wittingly or unwittingly transplant a species into anenvironment it's not native to.__(39)__.
The scientists say they recognize the potential pitfalls, and are keeping their worksafeguarded in the laboratory. With the impending arrival of this technology and the potentialto use it outside the lab, genetic engineering experts led by George Church of HarvardMedical School wrote a cautionary commentary in the journal Science. __(40)__(AB) During the course of study, people with the practice are sanguine toward the lucrativeresult. (AC) It warned of potential dangers and urged strict precautions. (AD) One could imagine algae engineered to grow more prolifically as a source of biofuel ordisease-resistant cattle. (AE) Without natural predators, the invasive species can run wild and produce undesiredeffects. (BC) In some areas, a single season might be enough to change the population. (BD) Other mosquito-borne diseases could possibly be controlled in this fashion as well.
【題組】36.