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A new microbicide built from two types of RNA has shown promise against HIV in lab experiments, but moving it toward becoming a marketable product is proving difficult. Alan Dove investigates what's interfering with this novel therapeutic RNA strategy.
The rat is the preferred model organism in many fields of biomedicine, such as toxicology testing. But when it comes to disease models, rats have been upstaged by mice, which traditionally were far easier to genetically engineer. Elie Dolgin follows the tale of the researchers who are bringing the rat back into the race.