In an effort to combat malaria, researchers at Imperial College London hope to take advantage of the female mosquito’s plight–and reduce the mosquito population–by engineering spermless males. They say the key is that the females don’t seem able to tell the difference; they still mate with the sterile males and proceed to lay eggs that never hatch.
This is an improvement over previous attempts to engineer sterile males, the team said, because that process often exposed the males to radiation, leaving them frail and unattractive to their female counterparts. In this latest achievement, the sterile males were just as attractive to females because the single difference from fertile males was an undetectable absence of sperm.
In work that was reported this week in the Proceedings of the National Academy of Sciences, entomologists injected 10,000 mosquito embryos with tiny fragments of RNA that turned off the gene “zpg,” which is key in sperm development.