Genetic variation in IL28B predicts hepatitis C treatment-induced viral clearance

Hepatitis C is one of the most common infections in the world. Many of its estimated 170 million sufferers live with the disease for years with no serious symptoms, but in about one in four patients it leads to cirrhosis of the liver. The discovery of a biomarker that predicts an individual's response to hepatitis C treatment raises the possibility that clinical outcomes could be improved by raising patient compliance to the often demanding interferon treatment regime. The new marker is a 'single letter' genetic variant — a C (cytosine) replacing a T (thymidine) in a segment of DNA near the IL28B gene that encodes interleukin 28B (interferon-γ-3). This finding goes some way towards explaining the different treatment outcomes between individuals of European (high IL28B frequency), African and Asian ancestry. And importantly, it is of immediate clinical utility.