本研究对鹅细小病毒（Goose parvovirus，GPV）SYG61v弱毒疫苗株与5个分离于不同年代的GPV强毒株，在编码蛋白氨基酸序列及非编码调控区碱基序列进行了比对，确定了SYG61v的特征性突变位点，而5个强毒株中这些位点均高度保守。SYG61v株的VP1和Rep1蛋白，分别产生了11个和10个氨基酸位点突变。Rep1的10个突变氨基酸中，7个均处于Rep1蛋白羧基端的100个氨基酸范围内，而VP1蛋白中的10个突变氨基酸中，推测仅有1个位点处于病毒衣壳表面。在左侧末端倒置重复序列（inverted terminal repeat, ITR）与P9启动子之间非编码区，存在两段共7个碱基的连续碱基突变。SYG61v弱毒株中突变位点的确认为进一步明确他们各自在弱毒株毒力减弱中的作用奠定了基础。%s:In the present study, the amino acid sequences of the coding proteins and non-coding nucleotide sequences were compared between the attenuated vaccine strain SYG61v and five virulent strains of Goose parvovirus (GPV) with various isolation years. The typical amino acids and nucleotides alterations in SYG61v were identified, while all of these sites were conserved for five virulent strains. Eleven and ten amino acid mutations occurred in the VP1 and Rep1 protein, respectively. Within the 10 mutated amino acids for the Rep1 protein of SYG61v, seven were observed in the scope of carboxyl terminal 100 amino acids, and only one mutation site in the VP1 protein was believed to lie in the surface domain of viral capsid. In the non-coding region between the left inverted terminal repeat (ITR)and P9 promoter, two places of consecutive nucleotide mutations were found in the SYG61v. Identification of the mutations sites in the SYG61v strain could help to further explore which site alterations actually contribute the attenuation of the virulent GPV after adaptive passages in the eggs.
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