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Scientists are hoping to eliminate malaria（疟疾）by developing a genetically modified mosquito that cannot transmit the disease.Malaria has long troubled the populations of South America，Africa，and Asia，where mosquito bites infect up to 500 million people a year with this serious and sometimes fatal parasitic blood disease.For generations，scientists have been trying to eliminate malaria by developing new drugs and using pesticides（杀虫剂）to wipe out local mosquito populations.But these measures aren’t working—and some scientists，like Greg Lanzaro，say that because of drug resistance and population changes，malaria is actually more prevalent now than it was 20 years ago.Lanzaro says he has a better way to stop the spread of malaria：genetically modify mosquitoes so they are unable to carry the disease.
Lanzaro and his colleagues are planning a multi-year project to produce malaria-resistant mosquitoes—and he thinks they can do it within five years.“We can get foreign genes into mosquitoes and they go where they’re supposed to go，”Lanzaro says，pointing out that scientists have already succeeded in genetically engineering mosquitoes that cannot transmit malaria to birds and mice.And，he says，scientists are quickly making progress on genes that block transmission of the disease to humans as well.
The most difficult part scientifically，Lanzaro says，is figuring out how to get the lab-engineered mosquitoes to spread their genes into natural populations.After all，he points out，it’s useless to engineer mosquitoes in the lab that can’t transmit malaria when there are millions out in the wild.To solve this problem，Lanzaro wants to load up a mobile piece of DNA with the malaria-resistant gene，and then insert it into a group of mosquito embryos.The malaria-resistant gene would be integrated directly into the mosquitoes’DNA，making it impossible for those mosquitoes to transmit the parasite that causes malaria.In this way a small group of lab-raised mosquitoes could be released into the wild，and by interbreeding with wild mosquitoes，eventually transmit the beneficial gene to the entire population.
重点词汇：
eliminate 消除（v.）
malaria 疟疾（n.）
genetically modified 转基因的
transmit 传播；传递（v.）
infect 感染，传染（v.）
fatal 致命的（adj.）
parasitic 寄生的（adj.）
pesticide 杀虫剂（n.）
resistance 抵抗（n.）
prevalent 流行的；普遍的（adj.）
embryo 胚胎（n.）(https://www.daowen.com)
block 阻碍（v./n.）
release 发放；发行；释放（v./n.）
难句解析：
①But these measures aren’t working—and some scientists，like Greg Lanzaro，say that because of drug resistance and population changes，malaria is actually more prevalent now than it was 20 years ago.
【结构分析】破折号连接了两个分句，第一个分句为these measures aren’t working，此处work的意思是“起作用”。第二个分句中主语为scientists，谓语为say，宾语为that引导的从句，该从句中表语为比较级，是malaria流行程度now与20 years ago的比较，because of
是宾语从句中的原因状语。
②“We can get foreign genes into mosquitoes and they go where they’re supposed to go，”Lanzaro says，pointing out that scientists have already succeeded in genetically engineering mosquitoes that cannot transmit malaria to birds and mice.
【结构分析】本句的主干为Lanzaro says，pointing out是现在分词充当伴随状语，out后面是that引导的宾语从句，宾语从句的主干为scientists have succeeded in engineering mosquitoes，that cannot transmit malaria to birds and mice是mosquitoes的定语从句。
③After all，he points out，it’s useless to engineer mosquitoes in the lab that can’t transmit malaria when there are millions out in the wild.
【结构分析】本句的主干是“it is+形容词+to do”结构，it为形式主语，动词不定式为真正的主语，在动词不定式中，that引导的定语从句修饰先行词mosquitoes，when引导从句充当定语从句中的时间状语。
④The malaria-resistant gene would be integrated directly into the mosquitoes’DNA，making it impossible for those mosquitoes to transmit the parasite that causes malaria.
【结构分析】本句中的making it impossible结构是现在分词充当伴随状语，此处的it是形式宾语，后面的动词不定式为真正的宾语，for those mosquitoes to
中的mosquitoes为动词不定式中动作的逻辑主语。
全文翻译：
科学家们希望通过培育出能够阻止病毒传播的转基因蚊子来根除疟疾。疟疾长期困扰着南美洲、非洲和亚洲的居民。在这些地方每年有多达5亿的人口因蚊子叮咬而传染上这种严重的、有时甚至是致命的寄生虫性血液疾病。历代的科学家们一直试图通过研制新药或使用杀虫剂来消灭当地蚊子的方法来根除疟疾。但是这些方法都没有奏效——一些科学家，如格雷格·兰萨罗说，因为蚊子的抗药性以及其种群的演变，实际上疟疾现在的传播程度比20年前有过之而无不及。兰萨罗说他有一套更好的办法可以切断疟疾的传播：对蚊子进行基因改造，这样它们就无法携带疟疾的病原体。
兰萨罗和他的同事正在规划一个为期多年的项目，培育携带疟疾抗体的蚊子——他认为他们能够在五年内培育成功。兰萨罗说：“我们可以把异体基因植入蚊子体内，然后让它们飞到指定的地方。”兰萨罗指出科学家已经成功地在蚊子身上进行了基因改造，使它们无法将疟疾传播给鸟类和老鼠。同时他还说，科学家们很快地在研究基因方面取得了进展，以杜绝蚊子将疟疾也传播给人类。
兰萨罗说，科技上最困难的部分是想办法使抗疟疾基因从在实验室内接受了疟疾基因改造工程的蚊子传播到蚊子的自然种群中去。他指出，毕竟，当数百万的蚊子还能在野外传播疟疾时，在实验室中改造蚊子基因，使其不传播疟疾是没有用的。为了解决这个问题，兰萨罗打算将携带动态单体DNA的抗疟疾基因植入一组蚊子的胚胎中。抗疟疾基因将会直接和蚊子的DNA结合在一起，这就阻断了疟疾致病菌的传播。这样一来，一小群实验室培育的蚊子被释放到野地中，然后通过与野生蚊子交配繁殖，最终将有益的基因传播到整个种群中。