TY - JOUR
T1 - Novel variants related to TT virus distributed widely in China
AU - Luo, Kangxian
AU - He, Haitang
AU - Liu, Zhihua
AU - Liu, Dingxie
AU - Xiao, Hong
AU - Jiang, Xiaojing
AU - Liang, Weifang
AU - Zhang, Lian
PY - 2002
Y1 - 2002
N2 - TTV is a DNA virus with high genetic heterogeneity. To investigate the novel isolates of the virus, blood samples were collected from subjects who lived in various parts of China and suffered from hepatitis or were asymptomatic carriers. Nested PCR was carried out to amplify a 3.2-kb fragment using primers deduced from the prototype TTV (TA278). The ten entire 3.2-kb nt sequences were aligned with isolate TA278, SANBAN, TUS01, and SENV retrieved from GenBank, and a phylogenetic tree was constructed by Neighbor-Joining method. The analysis indicated that five novel variants of the present study have not been described before, and all TTV-related isolates could be classified into three groups. The isolate TCHN-A, B and TUS01 were included in a group, and the remaining novel isolates together with SANBAN and TA278 clustered into another group, while SEN virus formed a distinct group. The genetic distances of the five novel variants were 0.5507-0.8476 to TA278, 0.4635-0.7877 to SANBAN, 0.6064-0.7834 to TUS01 and 0.6936-0.8236 to SENV. Of these novel variants, the ORF1 consisted of 426-772 aa and ORF2 of 141-156 aa. The nt identities of ORF1 and ORF2 between those variants and TA278, SANBAN, and TUS01 were 46.1-60.8 and 48.7-63.6%, and those of aa sequences were only 27.1-52.4 and 28.9-45.5%, respectively. The first 65 aa of ORF1 were rich in arginine and most conserved with homology of 56.5-70.0%. There was a hypervariable region from aa 286 to 403 with merely 17.7-27.0% of identity. Despite a low aa identity between TA278 and the variants, they have similar hydrophilicity profiles of ORF1. There were 2-10 N-glycosylation motifs found in these variants. In conclusion, despite the high divergence, sequences of all these isolates shared common genome organisation, ORF structure, hydrophilicity patterns, and some potential motifs with TTV prototype. It is suggested that various TTV and TTV-related isolates belong to a very large and complex family, which remains to be studied.
AB - TTV is a DNA virus with high genetic heterogeneity. To investigate the novel isolates of the virus, blood samples were collected from subjects who lived in various parts of China and suffered from hepatitis or were asymptomatic carriers. Nested PCR was carried out to amplify a 3.2-kb fragment using primers deduced from the prototype TTV (TA278). The ten entire 3.2-kb nt sequences were aligned with isolate TA278, SANBAN, TUS01, and SENV retrieved from GenBank, and a phylogenetic tree was constructed by Neighbor-Joining method. The analysis indicated that five novel variants of the present study have not been described before, and all TTV-related isolates could be classified into three groups. The isolate TCHN-A, B and TUS01 were included in a group, and the remaining novel isolates together with SANBAN and TA278 clustered into another group, while SEN virus formed a distinct group. The genetic distances of the five novel variants were 0.5507-0.8476 to TA278, 0.4635-0.7877 to SANBAN, 0.6064-0.7834 to TUS01 and 0.6936-0.8236 to SENV. Of these novel variants, the ORF1 consisted of 426-772 aa and ORF2 of 141-156 aa. The nt identities of ORF1 and ORF2 between those variants and TA278, SANBAN, and TUS01 were 46.1-60.8 and 48.7-63.6%, and those of aa sequences were only 27.1-52.4 and 28.9-45.5%, respectively. The first 65 aa of ORF1 were rich in arginine and most conserved with homology of 56.5-70.0%. There was a hypervariable region from aa 286 to 403 with merely 17.7-27.0% of identity. Despite a low aa identity between TA278 and the variants, they have similar hydrophilicity profiles of ORF1. There were 2-10 N-glycosylation motifs found in these variants. In conclusion, despite the high divergence, sequences of all these isolates shared common genome organisation, ORF structure, hydrophilicity patterns, and some potential motifs with TTV prototype. It is suggested that various TTV and TTV-related isolates belong to a very large and complex family, which remains to be studied.
KW - Genetic hetrogeneity
KW - TT virus
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U2 - 10.1002/jmv.2200
DO - 10.1002/jmv.2200
M3 - Article
C2 - 11920826
AN - SCOPUS:0036211405
SN - 0146-6615
VL - 67
SP - 118
EP - 126
JO - Journal of Medical Virology
JF - Journal of Medical Virology
IS - 1
ER -