Gharbi-Khelifi Hakima, Ferre Virginie, Sdiri Khira, Berthome Mathilde, Fki Lamia, Harrath Rafik, Billaudel Sylviane, Aouni Mahjoub
Laboratoire des Maladies Transmissibles et Substances Biologiquement Actives, Faculté de Pharmacie de Monastir, rue Avicenne, 5000 Monastir, Tunisia.
J Virol Methods. 2006 Dec;138(1-2):109-16. doi: 10.1016/j.jviromet.2006.08.001. Epub 2006 Sep 26.
Tunisia is a highly endemic area for hepatitis A virus (HAV) infection. In the present study, the phylogenetic characterization of the VP1 gene (882 nucleotides) and of the VP1/2A junction (336 nucleotides) of Tunisian strains were examined. One hundred strains isolated from patient with anti-HAV IgM from 2001 to 2004 were amplified by RT-PCR, sequenced at the VP1 and at the VP1/2A junction and aligned with the published sequences to establish phylogenetic analysis. All Tunisian strains belong to genotype I with a greater presence of sub-genotype IA (98%) originate from most of Tunisian regions and 2% of sub-genotype IB. In addition, sub-genotype IA and IB strains formed 25 different clusters. Genetically similar strains were also identified between 2001 and 2004 isolated from the southern and the central part of Tunisia, suggesting that an indigenous strain has been circulating in the Tunisia. The genetic profile of the VP1 region showed that Tun159-02 and Tun40-03 clustered respectively in the IB and IA sub-genotype, however, analysis of VP1/2A junction revealed in contrast that Tun159-02 and Tun40-03 clustered respectively in IA and IB. This is the first report to identify sub-genotype IA in Tunisia and provides new data on the genetic relatedness of HAV from Tunisia and the distribution of sub-genotype IA in this part of the world.
突尼斯是甲型肝炎病毒（HAV）感染的高流行地区。在本研究中，对突尼斯毒株的VP1基因（882个核苷酸）和VP1/2A连接区（336个核苷酸）进行了系统发育特征分析。从2001年至2004年抗HAV IgM阳性患者中分离出的100株毒株通过RT-PCR进行扩增，对VP1和VP1/2A连接区进行测序，并与已发表序列进行比对以建立系统发育分析。所有突尼斯毒株均属于I型基因型，其中IA亚型占比更高（98%），来自突尼斯的大部分地区，IB亚型占2%。此外，IA和IB亚型毒株形成了25个不同的簇。在2001年至2004年期间，从突尼斯南部和中部分离出的毒株之间也鉴定出了基因相似的毒株，这表明突尼斯存在一种本土毒株在传播。VP1区域的基因图谱显示，Tun159 - 02和Tun40 - 03分别聚集在IB和IA亚型中，然而，VP1/2A连接区的分析结果却相反，Tun159 - 02和Tun40 - 03分别聚集在IA和IB亚型中。这是首次在突尼斯鉴定出IA亚型的报告，并提供了有关突尼斯HAV基因相关性以及该亚型在世界这一地区分布的新数据。
