High Conservation of Hepatitis B Virus Surface Genes during Maternal Vertical Transmission despite Active and Passive Vaccination

Objective: Our purpose was to explore the relationship between hepatitis B virus (HBV) gene heterogeneity and maternal vertical transmission. Methods: HBsAg-positive mothers and their neonates were selected and classified into a vertical infection neonate group (group N), a vertical infection mother group (group M) and a control group (group C). Serum HBsAg and HBeAg were examined. HBV gene fragments, including the pre-S1, and pre-S2 and S coding regions, were amplified and sequenced, and the genotype and serotype of the sequences were identified. Mutation sites and frequency of mutations were then compared between group N and group C. Results: A total of 104 HBV clone sequences were obtained. All obtained sequences belonged to genotype C and serotype adr. Upon comparing sequences between group N and group C, 4 nonsynonymous mutations were found with significant difference in mutation frequency (p ! 0.05). When the mothers were both HBsAg and HBeAg positive, 10 nonsynonymous mutations were found. The frequencies of these mutations were significantly lower in group N than in group C (p ! 0.05). Conclusion: The 10 HBV mutations were negatively associated Received: December 28, 2009 Accepted after revision: June 17, 2010 Published online: October 19, 2010 Yong-Ping Yan and De-Zhong Xu Department of Epidemiology , Fourth Military Medical University No. 17, Changle West Road, Xi’an 710033 (China) E-Mail yanyping @ fmmu.edu.cn, xudezh @ fmmu.edu.cn © 2010 S. Karger AG, Basel 0300–5526/11/0543–0122$38.00/0 Accessible online at: www.karger.com/int H.-X.S. and Y.-H.Z. contributed equally to this paper. D ow nl oa de d by : 54 .7 0. 40 .1 1 11 /1 9/ 20 17 1 2: 12 :4 7 P M