The predominant genotypes of hepatitis B virus in Thailand

Theamboonlers, Apiradee; Jantaradsamee, P.; Kaew-in, Nopparat; Tangkijvanich, Pisit; Hirsch, Petra; Poovorawan, Yong

doi:10.1080/00034983.1999.11813479

Cited by 32 publications

(49 citation statements)

References 11 publications

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“…Genome sequence analysis is ideal to distinguish between closely related isolates, but it is a laborious and expensive technique. RFLP is a simple method to determine HBV strain variability, and it has been applied recently to determine genotypes by characterizing amplified fragments of HBV genome [Lindh et al, 1997[Lindh et al, , 2000Mizokami et al, 1999;Theamboonlers et al, 1999]. The RFLP method used in the present study allows the identification of the major HBV genotypes (A, D, and F) circulating in the South American population [Moraes et al, 1996;Blitz et al, 1998;Mbayed et al, 1998] and provides their subclassification into a larger number of RFLP patterns (Table I).…”

Section: Discussionmentioning

confidence: 95%

“…This technique, however, is not available to most research laboratories in developing countries. HBV genotyping by restriction fragment length polymorphism (RFLP) analysis is a simpler method for HBV strain characterization, and comparison between different RFLP patterns can be useful to elucidate transmission routes of HBV [Theamboonlers et al, 1999;De Castro et al, 2000;Lindh et al, 2000].…”

Section: Introductionmentioning

confidence: 99%

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Hepatitis B virus transmission in Brazilian hemodialysis units: Serological and molecular follow‐up

Teles¹,

Martins²,

Gomes³

et al. 2002

Journal of Medical Virology

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A serological and molecular study of hepatitis B virus (HBV) infection was carried out in dialysis units in Central Brazil. Between 1995 and 1999, serum samples from all HBsAg-positive hemodialysis patients (n = 43) were tested for HBeAg/anti-HBe and subtyping by monoclonal ELISA. HBV DNA was detected by PCR and positive samples were genotyped by restriction fragment polymorphism pattern (RFLP) methodology. TheHBsAg prevalence declined in this population during the survey period (12-5.8%). HBeAg and anti-HBe were detected in 23 (53.5%) and 18 (41.9%) sera, respectively. Thirty-six samples could be HBsAg subtyped: 21 were subtype ayw(3), 14 belonged to adw(2) and one was identified as adw(4). HBV DNA was present in 30 serum samples. Of these, 20 (66.7%) were genotype D, 9 (30%) genotype A, and 1 (3.3%) genotype F. In addition, the RFLP pattern could be determined in samples from 18/20 genotype D patients: D3 (10 strains), D7 (7 strains) and D4 (1 strain); from 8/9 genotype A patients: A1 (6 strains) and A3 (2 strains); and from the patient infected with genotype F: F1. Patterns D3 and D7 were associated closely with HBV infection in the two largest hemodialysis units studied. These findings confirm the value of the RFLP method as an effective molecular epidemiological tool for elucidating HBV transmission in hemodialysis units.

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Section: Discussionmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 99%

Hepatitis B virus transmission in Brazilian hemodialysis units: Serological and molecular follow‐up

Teles¹,

Martins²,

Gomes³

et al. 2002

Journal of Medical Virology

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“…HBV genotypes have distinct geographical distributions (11,21). In general, genotypes B and C are prevalent in Asia (8,26), whereas genotypes A and D prevail in Western countries (17). Genotype E is restricted to Africa, and genotype F prevails in Central America.…”

Section: Discussionmentioning

confidence: 99%

Clinical and Virological Aspects of Blood Donors Infected with Hepatitis B Virus Genotypes B and C

et al. 2002

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Pathogenic and therapeutic differences among hepatitis B virus (HBV) genotypes have been documented. However, the association of virological characteristics with clinical differences among HBV genotypes remains unclear. We therefore studied the clinical and virological characteristics of Taiwanese volunteer blood donors infected with HBV genotypes B and C. HBV genotypes were determined in 300 candidate blood donors positive for HBV surface antigen (HBsAg), and sequences of the precore gene of the HBV genome were determined in 50 HBV e antigen (HBeAg)-positive and 50 HBeAg-negative blood donors. Of 300 HBsAg-positive blood donors, 10% had elevated serum aminotransferase levels and 27% were positive for HBeAg. HBV genotype distribution in 264 viremic carriers was as follows: B, 221 (83.7%); C, 39 (14.8%); F, 1 (0.4%); and mixed infection, 3 (1.1%). Blood donors with genotype C infection tended to have a higher frequency of HBeAg positivity and a higher serum HBV DNA level than those with genotype B infection. The frequency of precore stop codon mutation was significantly higher in HBeAg-negative blood donors than HBeAg-positive ones, irrespective of HBV genotypes. Meanwhile, only 5% of blood donors with genotype C infection had C-1858 strains. In conclusion, mixed infection of HBV genotypes indeed occurs, and genotype C has a higher serum HBV DNA level than genotype B. Precore stop codon mutation is common in HBeAg-negative HBV carriers, irrespective of HBV genotypes. In contrast, precore C-1858 strains are rarely identified in Taiwanese HBV genotype C.Hepatitis B virus (HBV) infection is a global health problem, and more than 350 million people of the world population are chronic carriers of the virus (7). The infection is associated with a wide clinical spectrum, ranging from acute or fulminant hepatitis to various forms of chronic infection, including asymptomatic carrier status, chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC) (3, 7). Although serological and genotypic classifications of HBV have been well documented (20, 24), the clinical significance of HBV genotypes in terms of clinical outcomes and therapeutic response to antiviral therapy in patients with chronic HBV infection remained largely unknown until recently. Our previous studies indicated that HBV genotypes B and C are the most prevalent viral strains in Taiwan, and genotype C is associated with the development of cirrhosis and HCC while genotype B may be associated with the development of HCC in young patients (8). In addition, HBV genotype C is associated with a higher frequency of core promoter mutation and a lower response rate to alpha interferon therapy compared to genotype B (10). Taken together, these data suggest the possible pathogenic and therapeutic differences among HBV genotypes. However, the association of virological characteristics, including efficiency of viral replication as well as viral genome variability, with these clinical differences among HBV genotypes remains unclear. We therefore studied the clinical fe...

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“…Overall, 99 of the 109 patients (91%) could be typed by laboratory procedures, (i) 87 were clearly typed using the RFLP method on a pre S amplicon between nucleotide (nt) 2823 and 80, according to Lindh algorithm [Lindh et al, 1998;Theamboonlers et al, 1999]; (ii) six could only be determined by sequencing because of a too small amount of material for RFLP analysis; (iii) the 6 remaining patients showed atypical RFPL patterns. Among these 6 atypical patterns, one was described previously by Lindh et al [1998] as an untypable (UT) pattern 1 (UT1), and the 5 others corresponded to 5 new patterns found in each HBV genotype.…”

Section: Hbv Genotypingmentioning

confidence: 99%

Significance of hepatitis B virus genotypes A to E in a cohort of patients with chronic hepatitis B in the Seine Saint Denis District of Paris (France)

et al. 2006

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The aim of this study was to examine the genetic variability of the hepatitis B virus (HBV) and its significance. HBV genotypes, core promoter and precore mutants were characterized in 109 consecutive patients with biopsy-proven HBV chronic hepatitis. Genotypes A (26.6%), B (12.8%), C (18.3%), D (18.3%), and E (14.7%) indicate a wide genotypic distribution. Patients were from Asia (30.3%), Europe (28.4%), Sub Saharan Africa (23.9%), the Caribbean (10.1%), North Africa (5.5%), and Madagascar (1.8%). HBV genotypes A and D (HBV/A and /D) infected all subgroups except Asian patients. HBV/B or /C were found in 97% of Asian patients, whereas HBV/E only infected sub-Saharan African and Caribbean patients. Differences according to genotypes were: an increased prevalence of anti-HBe antibodies in patients infected with HBV/D (P = 0.003), higher serum transaminases in patients infected with HBV/A and/D (P = 0.043), more severe liver fibrosis in patients infected with HBV/A, /C and/D (P = 0.02). Precore and core promoter mutants were found in 87% of anti-HBe positive patients, and were associated with HBV/D (P = 0.04) and severe liver fibrosis (P = 0.002). It is concluded that HBV genotypes A, B, C, D, and E circulate in the Seine Saint Denis District, reflecting the geographical origin of patients. HBV/A, /C and/D seem to be associated with more severe hepatic disease.

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The predominant genotypes of hepatitis B virus in Thailand

Cited by 32 publications

References 11 publications

Hepatitis B virus transmission in Brazilian hemodialysis units: Serological and molecular follow‐up

Hepatitis B virus transmission in Brazilian hemodialysis units: Serological and molecular follow‐up

Clinical and Virological Aspects of Blood Donors Infected with Hepatitis B Virus Genotypes B and C

Significance of hepatitis B virus genotypes A to E in a cohort of patients with chronic hepatitis B in the Seine Saint Denis District of Paris (France)

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