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目的:分析并比较2016年浙江省温岭地区EV71型轻、重症手足口病(HFMD)患儿病毒分离株VP1和VP4区基因特征及进化关系。方法:研究对象为2016年浙江省温岭市第一人民医院分离鉴定的EV71型HFMD患儿，随机选取轻、重症HFMD患儿EV71病毒株各6例，进行VP1和VP4区基因扩增和测序，利用DNAStar和Mega 6.0软件对测序结果与美国国立生物信息中心公布的EV71典型基因代表株(A、B1～5、C1～4亚型)进行核苷酸和氨基酸比对分析，并构建系统进化树。结果:轻、重症手足口病患儿性别(χn 2＝14.51，n P<0.05)和年龄(n t＝2.82，n P<0.05)差异无统计学意义。两组EV71分离株的VP1区核苷酸同源性为95.8%～99.6%，氨基酸同源性为99.1%～100%；VP4区核苷酸同源性为95.0%～99.9%，氨基酸同源性为99.0%～100%，轻、重症EV71分离株同源性高。它们与典型C4a基因型代表株最接近，氨基酸同源性为：96.6%～100%(VP1)和94.3%～100%(VP4)。3例EV71型重症HFMD患儿分离株分别出现VP1区V170L突变(缬氨酸→亮氨酸)，VP1区A293S(丙氨酸→丝氨酸)以及VP4区T7A(苏氨酸→丙氨酸)，其他未见明显突变。n 结论:2016年浙江温岭地区轻、重症HFMD患儿EV71病毒分离株VP1和VP4区同源性高，且均属于C4a基因亚型。其中几个位点的氨基酸突变可能与浙江温岭地区HFMD患儿疾病危重有关。“,”Objective:To analyze and compare VP1 and VP4 genetic characteristics of human enterovirus 71(EV71) isolated from children with severe and mild hand-foot and mouth disease(HFMD).Methods:EV71 strains isolated from severe HFMD patients (6 cases) and mild HFMD patients (6 cases) in Taizhou district, Zhejiang province were included during 2016.Total virus RNA was extracted by Viral RNA Mini Extraction Kit, and reverse transcription polymerase chain reaction(RT-PCR) was used to amplify the sequence of the VP1 and VP4 genes of EV71.And then the sequencing results were compared with those of A, B, C genotype reference EV71 strains from GenBank by nucleotide alignment and amino acid alignment analysis.Results:There were no statistically significant differences in sex and age between the two groups(χn 2=14.51, n t=2.82, all n P<0.05). The homogeneity between EV71 strains from severe patients and mild patients was 95.8%~99.6% and 99.1%~100.0% for VP1 nucleotide sequences and amino acid sequences, respectively, while 95.0%~99.9% and 99.0%~100.0% for VP4 nucleotide sequences and amino acid sequences, respectively.The twelve EV71 strains isolated from HFMD patients in Taizhou shared the highest identity with EV71-genotype C, especially genotype C4a.In addition, compared with the mild patients, three respective strains from severe HFMD patients showed mutations at the residue 170 in the VP1 protein(V→L), residue 293 in the VP1 protein(A→S) and residue 7 in the VP4 protein(T→A).n Conclusion:All EV71 strains isolated from severe and mild HFMD patients in Taizhou district share high homology of nucleotide and amino sequence, and all of them belong to subgenogroup C4a.The mutations in the VP1 and VP4 of EV71 might be related to HFMD disease severity.