Heterogeneity analysis of the hepatitis B virus genome in intrauterine infection.
There are many factors leading to intrauterine infection with hepatitis B virus (HBV). These factors include viral structure, HBV mutations, HBV DNA level, placenta barrier, immune status of the mother, and susceptibility of the fetus. The purpose of this study was to investigate the possible relationship between intrauterine infection with and HBV mutations of the genome of the virus. In this study, HBsAg-positive mothers were divided into two groups: intrauterine infection group and non-infection group according to whether the newborn infants were infected or not. The intrauterine infection group included four pairs of mother and their newborn infants infected in utero, and non-infection group included five HBsAg-positive mothers. HBV sequences from the two groups were analyzed and compared. The predominant strains in the mothers and infants from the intrauterine infection group were not completely consistent. This suggested that both HBV predominant strains and minority strains in the mothers could infect their infants through intrauterine transmission. Some HBV mutations probably related to intrauterine infection were examined and it was found that the frequencies of mutations were low in isolates of the virus of infants from the intrauterine infection group and high in the non-infection group. These results suggest that some strains of HBV from the mother may be transmitted selectively to the fetus in utero because of viral heterogeneity. The strains without screened mutations such as P21L in the pre-S1 region may infect the fetus more readily.
Su
Hai-Xia
HX
Department of Epidemiology, Faculty of Preventive Medicine, Fourth Military Medical University, Xi'an, China.
Xu
De-Zhong
DZ
Li
Duan
D
Zhang
Jing-Xia
JX
Lu
Juan
J
Choi
Bernard C K
BC
Yan
Yong-Ping
YP
D000328:Adult; D019943:Amino Acid Substitution; D001483:Base Sequence; D004279:DNA, Viral / Q000097:blood; D005260:Female; D005315:Fetal Diseases / Q000821:virology; D006509:Hepatitis B / Q000635:transmission* / Q000821:virology*; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000235:genetics*; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D009154:Mutation; D010802:Phylogeny; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000821:virology; D014764:Viral Proteins
D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D014764:Viral Proteins