Epidemiological study of hepatitis B virus genotypes, core promoter and precore mutations of chronic hepatitis B infection in Hong Kong.
OBJECTIVE
We conducted a population study to document the prevalence of hepatitis B virus (HBV) genotypes in Hong Kong.


METHODS
HBV genotypes, core promoter (CP) and precore mutations were determined in 776 asymptomatic patients.


RESULTS
92.6% patients had single genotype [B (32.5%), C (62.5%)]. 99.1% of genotype B was subtype Ba. Patients with age <50 years had a lower prevalence of genotype B than patients with age >51 years (32.5% vs. 41%, respectively, P=0.028). Compared to patients with genotype C, patients with genotype B had a higher cumulative rate (P=0.018) and younger age (40.1 vs. 34.2 years, respectively, P=0.018) of HBeAg seroconversion. There were no differences in the HBV DNA levels between patients with genotypes B and C, and with wild-type and mutants of CP and precore regions. By multivariate analysis, patients with genotype C and with CP mutations had higher alanine aminotransferase (ALT) levels.


CONCLUSIONS
B and C were the two most common HBV genotypes in Hong Kong. The former had a higher chance of earlier HBeAg seroconversion and lower ALT levels. The prevalence of genotype B was lower in patients with age <50, probably related to influx of immigrants from China since 1949.
Yuen
Man-Fung
MF
Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, People's Republic of China.
Sablon
Erwin
E
Tanaka
Yasuhito
Y
Kato
Takanobu
T
Mizokami
Masashi
M
Doutreloigne
Joke
J
Yuan
He-Jun
HJ
Wong
Danny Ka-Ho
DK
Sum
Siu-Man
SM
Lai
Ching-Lung
CL
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000410:Alanine Transaminase / Q000097:blood; D001663:Bilirubin / Q000097:blood; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000097:blood; D005260:Female; D005838:Genotype; D006510:Hepatitis B Antibodies / Q000097:blood; D006513:Hepatitis B e Antigens / Q000235:genetics; D006515:Hepatitis B virus / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000453:epidemiology* / Q000276:immunology / Q000821:virology*; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D007223:Infant; D008099:Liver / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009154:Mutation; D015995:Prevalence; D011401:Promoter Regions, Genetic / Q000235:genetics; D012709:Serum Albumin
D004279:DNA, Viral; D006510:Hepatitis B Antibodies; D006513:Hepatitis B e Antigens; D012709:Serum Albumin; D000410:Alanine Transaminase; D001663:Bilirubin