Abstract:
In Europe, most HTLV-1-infected individuals originate from highly endemic regions such as West Indies, sub-Saharan Africa, and South America. The only genuine endemic region for HTLV-1 in Europe is Romania where ATL series have been reported among Romanian patients. Our objective is to better understand the origin of this endemic focus based on a study of the genetic diversity of HTLV-1 in Romanians. DNA was obtained from PBMCs/buffy coats of 11 unrelated HTLV-1-infected individuals of Romanian origin. They include 9 ATL cases and 2 asymptomatic carriers. LTR sequences were obtained for all specimens. Complete genomic HTLV-1 sequences were obtained using four PCR series on 10 specimens. Phylogenetic trees were generated from multiple alignments using HTLV-1 prototypic sequences and the new generated sequences. Most of the complete LTR sequences (756-bp) showed low nucleotide diversity, ranging from 0% to 0.8% difference, and were closely related (less than 0.8% divergence) to the only previously characterized Romanian strain, RKI2. One strain, ROU7, diverged slightly (1.5% on average) from the others. Phylogenetic analyses both on partial LTR and the complete genome demonstrate that the 11 sequences belong to the HTLV-1a cosmopolitan genotype and 10 of them belong to the previously denominated a-TC Mozambique-Southern Africa A subgroup. In this study, we demonstrated that the HTLV-1 present in Romania most probably originated in Southern Africa. As most Romanian HTLV-1 strains are very closely related, we can assume that HTLV-1 has been introduced into the Romanian population recently. Further studies are ongoing to decipher the routes of arrival and dissemination of these HTLV-1 strains, and to date the emergence of this endemic focus in Central Europe.
摘要:
在欧洲,大多数HTLV-1感染的个体来自西印度群岛等高度流行的地区,撒哈拉以南非洲,和南美洲。欧洲唯一真正的HTLV-1流行地区是罗马尼亚,罗马尼亚患者中有ATL系列报道。我们的目标是根据对罗马尼亚人HTLV-1遗传多样性的研究,更好地了解这种特有重点的起源。DNA是从11个无关的罗马尼亚裔HTLV-1感染个体的PBMC/血沉棕黄层中获得的。其中包括9例ATL病例和2例无症状携带者。获得所有样本的LTR序列。在10个样本上使用四个PCR系列获得完整的基因组HTLV-1序列。使用HTLV-1原型序列和新产生的序列从多个比对产生系统发育树。大多数完整的LTR序列(756-bp)显示低核苷酸多样性,从0%到0.8%的差异,并且与以前唯一表征的罗马尼亚菌株密切相关(差异小于0.8%),RKI2.一株,ROU7,与其他略有不同(平均1.5%)。对部分LTR和完整基因组的系统发育分析表明,这11条序列属于HTLV-1a世界性基因型,其中10条属于先前命名的a-TC莫桑比克-南部非洲A亚组。在这项研究中,我们证明,罗马尼亚的HTLV-1很可能起源于南部非洲。由于大多数罗马尼亚HTLV-1菌株非常密切相关,我们可以假设HTLV-1最近被引入罗马尼亚人口中。正在进行进一步的研究,以破译这些HTLV-1菌株的到达和传播途径,到目前为止,这种地方性焦点出现在中欧。