Nature：一种能够预测丙肝治疗预后的生物标记被发现
丙肝是世界上最常见的传染病之一。在估计存在的1.7亿感染者中，很多人患病多年都无严重症候，但约四分之一患者会转化成肝硬化。
一种能够预测一个人对丙肝治疗之反应的生物标记的发现表明，有可能通过提高患者对经常要求非常严格的干扰素治疗方法的遵从性来提高临床治疗效果。
这一新发现的生物标记是一个“单字母”基因变异体，在IL28B基因附近的一个DNA片段上一个字母C（代表胞嘧啶）替换了一个字母T（代表胸腺嘧啶）；IL28B基因编码白介素28B（interferon-lambda-3）。这一发现在一定程度上可解释欧洲裔（高IL28B频率）、非洲裔和亚洲裔个体之间为什么治疗效果有所不同。而且重要的是，它还可以立即投入临床应用。
Nature 461 , 399-401 (17 September 2009)
doi :10.1038/nature08309
Genetic variation in IL28B predicts hepatitis C treatment-induced viral clearance
Chronic infection with hepatitis C virus (HCV) affects 170 million people worldwide and is the leading cause of cirrhosis in North America 1 . Although the recommended treatment for chronic infection involves a 48-week course of peginterferon-alpha-2b (PegIFN- alpha-2b) or-alpha-2a(PegIFN-2a) combined with ribavirin (RBV), it is well known that many patients will not be cured by treatment, and that patients of European ancestry have a significantly higher probability of being cured than patients of African ancestry. In addition to limited efficacy, treatment is often poorly tolerated because of side effects that prevent some patients from completing therapy. For these reasons, identification of the determinants of response to treatment is a high priority. Here we report that a genetic polymorphism near the IL28B gene, encoding interferon-lambda-3 (IFN-lambda-3), is associated with an approximately twofold change in response to treatment, both among patients of European ancestry ( P = 1.06x10 -25 ) and African-Americans ( P = 2.06x 10 -3 ). Because the genotype leading to better response is in substantially greater frequency in European than African populations, this genetic polymorphism also explains approximately half of the difference in response rates between African-Americans and patients of European ancestry.
