Rola-Łuszczak Marzena, Sakhawat Ali, Pluta Aneta, Ryło Anna, Bomba Arkadiusz, Bibi Nazia, Kuźmak Jacek
Department of Biochemistry, National Veterinary Research Institute, 24-100 Puławy, Poland.
National Veterinary Laboratories, Islamabad 45500, Pakistan.
Pathogens. 2021 Jul 19;10(7):910. doi: 10.3390/pathogens10070910.
Characterization of the global genetic diversity of the bovine leukemia virus (BLV) is an ongoing international research effort. Up to now BLV sequences have been classified into eleven distinct genotypes. Although BLV genotyping and molecular analysis of field isolates were reported in many countries, there is no report describing BLV genotypes present in cattle from Pakistan. In this study we examined 27 gene sequences from BLV-infected cattle coming from four farms located in Khyber Pakhtunkwa, Gilgit Baltisan and Punjab provinces. Phylogenetic analyses revealed the classification of Pakistani sequences into genotypes G1 and G6. The alignment with the FLK-BLV sequence revealed the presence of 45 mutations, namely, seven in genotype G1 and 33 in genotype G6. Five mutations were found in both, G1 and G6 genotypes. Twelve amino acid substitutions were found in the analyzed sequences, of which only one P264S was specific for sequences from Pakistan. Furthermore, a certain degree of nucleotide heterogeneity was identified by NGS. These results highlight the need for further study on the importance of genetic variability of BLV, especially in the context of its pathogenicity and potential effect on serological detection.
牛白血病病毒（BLV）全球遗传多样性的特征分析是一项正在进行的国际研究工作。到目前为止，BLV序列已被分为11个不同的基因型。尽管许多国家都报道了BLV基因分型和田间分离株的分子分析，但尚无关于巴基斯坦牛群中存在的BLV基因型的报道。在本研究中，我们检测了来自开伯尔-普赫图赫瓦省、吉尔吉特-巴尔蒂斯坦省和旁遮普省四个农场的27份感染BLV的牛的基因序列。系统发育分析显示巴基斯坦序列被分类为G1和G6基因型。与FLK-BLV序列比对发现存在45个突变，其中G1基因型中有7个，G6基因型中有33个。在G1和G6基因型中均发现了5个突变。在分析的序列中发现了12个氨基酸替换，其中只有一个P264S是巴基斯坦序列特有的。此外，通过二代测序（NGS）鉴定出一定程度的核苷酸异质性。这些结果凸显了进一步研究BLV遗传变异性重要性的必要性，特别是在其致病性及其对血清学检测潜在影响方面。
