Presence and integration of HBV DNA in mouse oocytes.
OBJECTIVE
Hepatitis B is a worldwide public health problem. To explore the feasibility of hepatitis B virus (HBV) vertical transmission via oocytes, the presence and integration of HBV DNA in mouse oocytes were studied.


METHODS
Genomic DNA was isolated and metaphases were prepared, respectively from mouse oocytes cocultured with pBR322-HBV DNA plasmids. PCR, Southern blot, dot hybridization and fluorescence in situ hybridization (FISH) were performed to explore the existence and integration of HBV DNA in oocytes.


RESULTS
PCR detected positive bands in the tested samples, and then Southern blot revealed clear hybridization signals in PCR products. Final washing solutions were collected for dot hybridization and no signal for HBV DNA was observed, which excluded the possibility that contamination of washing solutions gave rise to positive results of PCR and Southern blot. FISH demonstrated that 36 of 1,000 metaphases presented positive signals.


CONCLUSIONS
HBV DNA sequences are able to pass through the zona and oolemma to enter into oocytes and to integrate into their chromosomes. HBV DNA sequences might be brought into embryo via oocytes as vectors when they are fertilized with normal spermatozoa.
Huang
Tian-Hua
TH
Research Center of Reproductive Medicine, Shantou University Medical College, 22 Xinling Road, Shantou 515041, Guangdong Province, China. thhuang@stu.edu.cn
Zhang
Qing-Jian
QJ
Xie
Qing-Dong
QD
Zeng
Li-Ping
LP
Zeng
Xi-Fan
XF
D000818:Animals; D004279:DNA, Viral / Q000502:physiology; D005260:Female; D006509:Hepatitis B / Q000635:transmission* / Q000821:virology*; D006515:Hepatitis B virus / Q000235:genetics* / Q000254:growth & development*; D018445:Infectious Disease Transmission, Vertical; D051379:Mice; D009865:Oocytes / Q000821:virology*; D016662:Virus Integration
D004279:DNA, Viral