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Basic Characteristics of Mutations
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Mutation Site
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T116N |
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Mutation Site Sentence
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Sequence analysis revealed an S gene mutant in HBsAg-seronegative serum with two consecutive amino acid substitutions: threonine115-to-isoleucine and threonine116-to-asparagine, whereas no amino acid substitution or deletion was found in the pre-S region. |
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Mutation Level
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Amino acid level |
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Mutation Type
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Nonsynonymous substitution |
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Gene/Protein/Region
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S |
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Standardized Encoding Gene
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S
|
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Genotype/Subtype
|
- |
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Viral Reference
|
-
|
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Functional Impact and Mechanisms
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Disease
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Hepatitis B, Chronic
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Immune
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- |
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Target Gene
|
-
|
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Clinical and Epidemiological Correlations
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Clinical Information
|
- |
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Treatment
|
- |
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Location
|
- |
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Literature Information
|
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PMID
|
9728561
|
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Title
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Emergence of an S gene mutant during thymosin alpha1 therapy in a patient with chronic hepatitis B
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Author
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Tang JH,Yeh CT,Chen TC,Hsieh SY,Chu CM,Liaw YF
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Journal
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The Journal of infectious diseases
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Journal Info
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1998 Sep;178(3):866-9
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Abstract
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The presence of a hepatitis B virus S gene mutant was investigated in a patient being treated with thymosin alpha1. He was seropositive for hepatitis B e antigen throughout therapy but was intermittently seronegative for hepatitis B surface antigen (HBsAg) by an RIA. Sequence analysis revealed an S gene mutant in HBsAg-seronegative serum with two consecutive amino acid substitutions: threonine115-to-isoleucine and threonine116-to-asparagine, whereas no amino acid substitution or deletion was found in the pre-S region. A site-directed mutagenesis experiment confirmed that these mutations were responsible for the failure to detect HBsAg. In summary, an S gene mutant was identified in an HBsAg-seronegative patient. The mutations were located outside the putative ""a"" determinant. The emergence of an S gene mutant during thymosin alpha1 treatment suggests that enhanced host immunity against HBsAg may play a role in its antiviral activity.
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Sequence Data
|
-
|