Zehender Gianguglielmo, Ebranati Erika, Gabanelli Elena, Sorrentino Chiara, Lo Presti Alessandra, Tanzi Elisabetta, Ciccozzi Massimo, Galli Massimo
Gianguglielmo Zehender, Erika Ebranati, Elena Gabanelli, Chiara Sorrentino, Massimo Galli, L. Sacco Department of Biomedical and Clinical Sciences, University of Milan, 20157 Milan, Italy.
World J Gastroenterol. 2014 Jun 28;20(24):7622-34. doi: 10.3748/wjg.v20.i24.7622.
Hepatitis B virus (HBV) is the leading cause of liver disease and infects an estimated 240 million people worldwide. It is characterised by a high degree of genetic heterogeneity because of the use of a reverse transcriptase during viral replication. The ten genotypes (A-J) that have been described so far further segregate into a number of subgenotypes which have distinct ethno-geographic distribution. Genotypes A and D are ubiquitous and the most prevalent genotypes in Europe (mainly represented by subgenotypes D1-3 and A2); genotypes B and C are restricted to eastern Asia and Oceania; genotype E to central and western Africa; and genotypes H and F (classified into 4 subgenotypes) to Latin America and Alaska. This review summarises the data obtained by studying the global phylodynamics and phylogeography of HBV genotypes, particularly those concerning the origin and dispersion histories of genotypes A, D, E and F and their subgenotypes. The lack of any consensus concerning the HBV substitution rate and the conflicting data obtained using different calibration approaches make the time of origin and divergence of the various genotypes and subgenotypes largely uncertain. It is hypothesised that HBV evolutionary rates are time dependent, and that the changes depend on the main transmission routes of the genotypes and the dynamics of the infected populations.
乙型肝炎病毒（HBV）是肝脏疾病的主要病因，全球估计有2.4亿人受到感染。由于病毒复制过程中使用逆转录酶，其具有高度的遗传异质性。迄今为止已描述的10种基因型（A - J）进一步细分为多个具有不同种族地理分布的亚型。基因型A和D分布广泛，是欧洲最常见的基因型（主要由D1 - 3亚型和A2亚型代表）；基因型B和C局限于东亚和大洋洲；基因型E分布于中非和西非；基因型H和F（分为4个亚型）分布于拉丁美洲和阿拉斯加。本综述总结了通过研究HBV基因型的全球系统动力学和系统地理学所获得的数据，特别是关于基因型A、D、E和F及其亚型的起源和传播历史的数据。由于缺乏关于HBV替代率的共识，以及使用不同校准方法获得的相互矛盾的数据，使得各种基因型和亚型的起源时间和分化时间在很大程度上不确定。据推测，HBV进化速率是时间依赖性的，并且这些变化取决于基因型的主要传播途径和感染人群的动态变化。
