AS WELL as carrying the paternal genome, sperm carry strands of RNA that could play a key role in embryonic development. The discovery might explain some forms of infertility and help improve techniques like cloning.
“Dad’s doing a little bit more than just adding his DNA,” says Stephen Krawetz of Wayne State University School of Medicine in Detroit, Michigan. He and his colleagues have already shown that, in addition to its payload of DNA, a sperm contains at least 3000 different types of RNA molecules, the blueprints for making proteins. Now, by fertilising hamster eggs with human sperm, they have proved that at least two different RNAs are released into the egg at the moment of conception (Nature,…
