The genetic makeup of HIV in semen differs from that of HIV in the bloodstream, according to a study published in the Public Library of Science online journal PLoS Pathogens and reported by The Seattle Times. Researchers at the University of North Carolina at Chapel Hill mapped the genomes of hundreds of viral samples taken from 16 Malawi men. It's the first study taking steps to prove the genetic difference. Current HIV research examines the virus in the blood, so it's hoped that study of seminal HIV will provide new information on how the virus is transmitted.

To read the Seattle Times article, click here.