VOA标准英语2012--Mosquitoes Genetically Modified to Prevent Malaria

Mosquitoes Genetically² Modified to Prevent Malaria³

There may soon be a new weapon in the fight against malaria - a genetically-modified mosquito that kills the disease-causing parasite⁴ once it becomes infected.

Malaria is a leading cause of death worldwide. The mosquito-borne illness was responsible for 655,000 deaths in 2010, according to the latest World Health Organization figures, most of them, young children in sub-Saharan Africa.

Researchers have genetically engineered mosquitoes to boost their immune system, thereby⁵ blocking transmission of the disease to humans.

The altered mosquitoes produce higher than normal levels of the immune system protein, Rel2. That activates⁶ a host of anti-parasitic molecules⁷ which, in turn, launch an all-out attack on the malaria parasite. The parasite enters the insect's gut⁸ after it takes a blood meal from infected humans.

“We’re basically attacking the parasite with multiple weapons at the same time as it is infecting the mosquito, and that will much make it more difficult for this parasite to develop resistance,” says George Dimopoulos at the Johns Hopkins University Malaria Research Institute in Baltimore, Maryland.

So far, the genetically modified, or GM, mosquitoes are breeding and living as long as normal mosquitoes. Dimopoulos says that’s good news because he hopes eventually to breed them with mosquitoes in the wild so off-spring are born with heightened immune systems.

While GM mosquitoes could be a powerful weapon against the dreaded⁹ disease Dimopoulos says it will remain only one tool in the fight against the deadly malaria parasite.

“Our approach, based on genetically-modified mosquitoes, will only work in areas where transmission of malaria is carried out by a single mosquito species and not multiple species of mosquitoes because we will not be able to genetically manipulate each one of them individually.”

Dimopoulos’s team worked with Anopheles gambiae mosquitoes, the principal carrier of the malaria parasite in Africa. They are continuing research to see whether the genetic¹ manipulation works on other species of mosquitos that transmit malaria parasites¹⁰.

1 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

2 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

3 malaria   

n.疟疾

参考例句：

• He had frequent attacks of malaria.他常患疟疾。
• Malaria is a kind of serious malady.疟疾是一种严重的疾病。

4 parasite   

n.寄生虫；寄生菌；食客

参考例句：

• The lazy man was a parasite on his family.那懒汉是家里的寄生虫。
• I don't want to be a parasite.I must earn my own way in life.我不想做寄生虫，我要自己养活自己。

5 thereby   

adv.因此，从而

参考例句：

• I have never been to that city,,ereby I don't know much about it.我从未去过那座城市，因此对它不怎么熟悉。
• He became a British citizen,thereby gaining the right to vote.他成了英国公民，因而得到了投票权。

6 activates   

使活动，起动，触发( activate的第三人称单数 )

参考例句：

• Activates the window and displays it in its current size and position. 激活窗口，保持当前的大小及位置不变。
• Pulling out the alarm switch activates alarm and pushing it deactivates it. 闹钟的开和关是通过拔出和按入闹铃开关实现的。

7 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

8 gut   

n.[pl.]胆量；内脏；adj.本能的；vt.取出内脏

参考例句：

• It is not always necessary to gut the fish prior to freezing.冷冻鱼之前并不总是需要先把内脏掏空。
• My immediate gut feeling was to refuse.我本能的直接反应是拒绝。

9 dreaded   

adj.令人畏惧的；害怕的v.害怕，恐惧，担心( dread的过去式和过去分词)

参考例句：

• The dreaded moment had finally arrived. 可怕的时刻终于来到了。
• He dreaded having to spend Christmas in hospital. 他害怕非得在医院过圣诞节不可。 来自《用法词典》

10 parasites   

寄生物( parasite的名词复数 )； 靠他人为生的人； 诸虫

参考例句：

• These symptoms may be referable to virus infection rather than parasites. 这些症状也许是由病毒感染引起的，而与寄生虫无关。
• Kangaroos harbor a vast range of parasites. 袋鼠身上有各种各样的寄生虫。