Head and body lice splice genes to be different

摘要

You'd struggle to tell them apart. Human head and body lice look similar, appear to share the same genome and are believed to be the same species. But they've never been seen to interbreed outside of the lab. What's more, while head lice (Pediculus humanus capitis) are known to be harmless, body lice (P. humanus corporis) transmit bacteria that cause typhus and trench fever. "Something has to be different between them," says Araxi Urrutia of the University of Bath, UK. Now Urrutia and her team have evidence that, although their genes seem to be the same, the two lice read them differently. They do so through a process called alternative splicing. Many genes are split into segments of coding and non-coding DNA. When these genes are expressed to make proteins, they are first copied into RNA. At this point the non-coding segments are spliced out and the important pieces of information are stitched together.