Molecular epidemiology and transmission of HBV

liver411

J Med Virol 2003 Aug;70(4):520-8

Molecular epidemiology and transmission of hepatitis B virus in close family
contacts of HBV-related chronic liver disease patients.

Thakur V, Kazim SN, Guptan RC, Malhotra V, Sarin SK
Department of Gastroenterology, G.B. Pant Hospital, New Delhi, India.

[Medline record in process]


There is limited data on the patterns of HBV mutation in family contacts of
chronic liver disease (CLD) patients in India. DNA sequence analysis is an
important tool to study this viral epidemiology. Transmission and prevalence
of mutations in the S and pre-C gene region in HBV infected close family
contacts of HBV-related CLD patients were studied. Twelve HBsAg(+) index
patients and their 20 HBV DNA contacts were studied in detail. The S ORF and
the pre-C region were sequenced using direct PCR products. S-gene sequencing
included 32 specimens (12 index cases and all 20 contacts). Pre-C gene
sequencing included 26 specimens (12 index cases and all the 14 HBsAg(+)
contacts irrespective of their HBeAg status). More than 98% sequence
homology was found between the index patients and their contacts. The
in-depth study of 12 families revealed that the transmission pattern was
primarily horizontal in 6 (50%) and vertical in 2 (17%) families (P < 0.05).
The remaining four families had evidence of both horizontal and vertical
transmission. Mutations in the S-gene were found in 80% of HBsAg(+) and 17%
HBsAg(-) subjects (P < 0.05). A total of 22-point mutations at different
nucleotide positions were found. In these, 16 (72%) were mutation of the "a"
determinant region and 14 (64%) resulted in missense mutations. The
commonest S-gene mutations were T118V and A128V, present in 44 and 38%
specimens, respectively. T143M and G145R mutations in the second loop of the
"a" determinant were found in 9% of the specimens. Novel mutations, C137stp
and C138stp were found in only one HBsAg(-) subject. Mutations in the pre-C
gene were common (91%) in patients with HBeAg(-) phenotype. G1896A mutation
was found in 7 of 11 (64%) specimens changing amino acid tryptophane (W) to
stop codon. Other mutations were at codons 25 and 29. The results of the
study, demonstrate (1) clustering of Pre-C and S-gene mutations in the
families, (2) horizontal mode of transmission and a common source infection
appears to be frequent as evidenced by sequence homology and detailed
history, (3) T118V and A128V were the commonest mutations in the S-gene
region, while (4) M2 (G1896A) was the commonest pre-C gene mutation, and (5)
long-term follow-up evaluation of these mutations suggested. J. Med. Virol.
70:520-528, 2003. Copyright 2003 Wiley-Liss, Inc.

PMID: 12794713, UI: 22679368

安心

是医学报告吗？
治疗过程中的药物反应的记录吗？
看不懂！

安心

是试验系统没有好，不是您没有好吧，呵呵
见到您很高兴啊！