[Hepatitis B surface antigen terminates codon bias selection].
OBJECTIVE
To investigate the existence condition of hepatitis B surface antigen(HBsAg) termination codon bias.


METHODS
A total of 174 reference sequences of all kinds of Hepatitis B virus(HBV) genotypes were chosen from GenBank, and compared by BioEdit. Then secondary structure of RNA was constructed and analyzed together.


RESULTS
(1) There were two types of HBsAg termination codon: TAA and TGA in 174 reference sequences. TAA was in 124 cases (71.26%); and TGA in 50 cases (28.74%). (2) There was codon bias selection in HBsAg termination codon, and it could affect the secondary structure of RNA and amino acid sequence encoding protein.


CONCLUSIONS
HBsAg termination codon bias exists and may be related to RNA structure and the conservation of protein function in the evolutionary progress.
Hepatology Institute, Peking University People's Hospital, Beijing, China.
Jun Qiang
JQ
Li
Jing Hua
JH
Tian
Feng
F
Liu
Shao Cai
SC
Du
D001483:Base Sequence; D018388:Codon, Terminator / Q000235:genetics*; D005838:Genotype; D006514:Hepatitis B Surface Antigens / Q000235:genetics*; D006515:Hepatitis B virus / Q000235:genetics* / Q000276:immunology; D006801:Humans; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012313:RNA / Q000235:genetics; D015983:Selection Bias
D018388:Codon, Terminator; D006514:Hepatitis B Surface Antigens; D012313:RNA