Naumann H, Schaefer S, Yoshida C F, Gaspar A M, Repp R, Gerlich W H
Institute of Medical Virology, Justus-Liebig-University, Giessen, Germany.
J Gen Virol. 1993 Aug;74 ( Pt 8):1627-32. doi: 10.1099/0022-1317-74-8-1627.
The complete genome of a hepatitis B virus (HBV) from Brazil that expressed the subtype adw4 of HBV surface antigen (HBsAg) was cloned and sequenced. The genome, termed w4B, consists of 3215 bp. The overall genetic organization of typical hepadnaviruses with four open reading frames including the preC region was found to be conserved. When comparing the w4B sequence with 19 complete HBV genomes it was, however, found to be more divergent (15%) than any other HBV sequence thus far reported. Until now, no more than 11% divergence has been reported. Distinct from the five known HBV genotypes A to E, w4B made up a new, sixth genotype. The importance of the conserved third start codon in the HBV X gene became apparent in isolate w4B. By mutation, this ATG was out of frame, and by what appears to have been a linked mutation, a new start site two codons downstream was re-established. The significance of several other mutations is discussed.
对一株来自巴西、表达乙型肝炎病毒（HBV）表面抗原（HBsAg）adw4亚型的HBV全基因组进行了克隆和测序。该基因组被命名为w4B，由3215个碱基对组成。发现具有包括前C区在内的四个开放阅读框的典型嗜肝DNA病毒的整体基因组织是保守的。然而，将w4B序列与19个完整的HBV基因组进行比较时，发现它比迄今为止报道的任何其他HBV序列差异更大（15%）。到目前为止，报道的差异不超过11%。与已知的A至E五种HBV基因型不同，w4B构成了一种新的第六基因型。在分离株w4B中，HBV X基因中保守的第三个起始密码子的重要性变得明显。通过突变，这个ATG发生了移码，并且通过一个似乎是连锁突变，在下游两个密码子处重新建立了一个新的起始位点。还讨论了其他几个突变的意义。
