英国研究人员在新一期美国《国家科学院院刊》上报告说，他们培育出一种无精蚊子，把这种无精蚊子大量投放到自然环境中可能有助于阻止疟疾传播。
疟疾由蚊子携带的疟原虫引起。随着抗药疟原虫的出现，控制疟疾日趋困难。许多科学家因此提出通过遗传学手段制造无精蚊子，让与其交配的雌蚊无法产生后代，从而根治疟疾。这一理论的关键在于，雌蚊能够不加区分地与这些雄蚊正常交配。
英国帝国理工学院贾尼斯·泰来易博士和同事报告说，他们通过注射一种蛋白质关闭制造精子所需的一种基因，在实验室中培育了100只无精疟蚊。结果发现，当雌蚊与这些雄蚊相遇之后，确实无法区分雄疟蚊是否绝育，仍正常与之交配并产卵，而卵由于没有受精，因此也不会孵化。
研究人员还惊讶地发现，与无精雄疟蚊交配之后，雌蚊就不愿意再次交配，这也有效减少了雌蚊所产卵受精的机会。
研究人员据此指出，投放大量无精蚊子到自然环境中，也许能阻止疟蚊数量增长并减少疟疾发生。不过，他们同时警告说，尽管无精蚊子将来或许能代替杀虫剂，但在让这种蚊子进入自然界之前仍需要进行更多的研究工作，如进一步了解疟蚊繁殖行为等。
疟疾是人类十大传染病之一。统计数据显示，全球每年有3亿人感染疟原虫，80万人死于疟疾，其中大部分集中在撒哈拉以南非洲地区。（生物谷Bioon.com）
Spermless males elicit large-scale female responses to mating in the malaria mosquito Anopheles gambiae
Thailayil, Janis; Magnusson, Kalle; Godfray, H. Charles J.; Crisanti, Andrea; Catteruccia, Flaminia
Anopheles gambiae sensu stricto is the major vector of malaria, a disease with devastating consequences for human health. Given the constant spread of thedisease, alternative approaches to the use of insecticides are urgently needed to control vector populations. Females of thisspecies undergo large behavioral changes after mating, which include a life-long refractoriness to further insemination andthe induction of egg laying in blood-fed individuals. Genetic control strategies aimed at impacting Anopheles fertility through the release of sterile males are being advocated to reduce the size of mosquito field populations. Suchstrategies depend on the ability of the released sterile males to mate successfully with wild females and to switch off thefemale receptivity to further copulation. Here we evaluate the role of sperm in regulating female behavioral responses aftermating in An. gambiae. We developed spermless males by RNAi silencing of a germ cell differentiation gene. These males mated successfully and preservedstandard accessory gland functions. Females mated to spermless males exhibited normal postcopulatory responses, which includedlaying large numbers of eggs upon blood feeding and becoming refractory to subsequent insemination. Moreover, spermless malesinduced transcriptional changes in female reproductive genes comparable to those elicited by fertile males. Our data demonstratethat, in contrast to Drosophila, targeting sperm in An. gambiae preserves normal male and female reproductive behavior for the traits and time frame analyzed and validate the use of approachesbased on incapacitation or elimination of sperm for genetic control of vector populations to block malaria transmission.
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