Daous Hala El, Mitoma Shuya, Elhanafy Eslam, Thi Nguyen Huyen, Thi Mai Ngan, Notsu Kosuke, Kaneko Chiho, Norimine Junzo, Sekiguchi Satoshi
Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, 5200 Kihara, Kiyotake-cho, Miyazaki 889-1692, Japan.
Faculty of Veterinary Medicine, Benha University, Moshtohor, Toukh, Qalyubia 13736, Egypt.
Animals (Basel). 2021 Mar 1;11(3):647. doi: 10.3390/ani11030647.
Enzootic bovine leukosis is a lethal neoplastic disease caused by bovine leukemia virus (BLV), belongs to family Retroviridae. The BLV proviral load (PVL) represents the quantity of BLV genome that has integrated into the host's genome in BLV-infected cells. Bovine leukocyte antigen () class II allelic polymorphisms are associated with PVLs in BLV-infected cattle. We sought to identify relationships between allelic heterozygosity and BLV PVLs among different cattle breeds. Blood samples from 598 BLV-infected cattle were quantified to determine their PVLs by real-time polymerase chain reaction. The results were confirmed by a BLV-enzyme-linked immunosorbent assay. Restriction fragment length polymorphism-polymerase chain reaction identified 22 alleles. Multivariate negative binomial regression modeling was used to test for associations between BLV PVLs and alleles. , , , , , , and alleles were significantly associated with low PVLs. was significantly associated with high PVLs. Some heterozygous allele combinations were associated with low PVLs , , , , and ; others were associated with high PVLs , , , , and . Interestingly, the heterozygous allele was always strongly and independently associated with low PVLs. This is the first reported evidence of an association between heterozygous allelic combinations and BLV PVLs.
地方流行性牛白血病是一种由牛白血病病毒（BLV）引起的致死性肿瘤疾病，该病毒属于逆转录病毒科。BLV前病毒载量（PVL）代表了在BLV感染细胞中整合到宿主基因组中的BLV基因组数量。牛白细胞抗原（）II类等位基因多态性与BLV感染牛的PVL相关。我们试图确定不同牛品种中等位基因杂合性与BLV PVL之间的关系。通过实时聚合酶链反应对598头BLV感染牛的血样进行定量，以确定它们的PVL。结果通过BLV酶联免疫吸附试验得到证实。限制性片段长度多态性聚合酶链反应鉴定出22个等位基因。使用多变量负二项回归模型来测试BLV PVL与等位基因之间的关联。、、、、、和等位基因与低PVL显著相关。与高PVL显著相关。一些杂合等位基因组合与低PVL相关（、、、和）；其他的与高PVL相关（、、、和）。有趣的是，杂合等位基因总是与低PVL强烈且独立相关。这是首次报道的杂合等位基因组合与BLV PVL之间存在关联的证据。
