Premium
A case‐control study for differences among hepatitis B virus infections of genotypes A (subtypes Aa and Ae) and D
Author(s) -
Tanaka Yasuhito,
Hasegawa Izumi,
Kato Takanobu,
Orito Etsuro,
Hirashima Noboru,
Acharya Subrat K.,
Gish Robert G.,
Kramvis Anna,
Kew Michael C.,
Yoshihara Namiko,
Shrestha Santosh Man,
Khan Mobin,
Miyakawa Yuzo,
Mizokami Masashi
Publication year - 2004
Publication title -
hepatology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.488
H-Index - 361
eISSN - 1527-3350
pISSN - 0270-9139
DOI - 10.1002/hep.20365
Subject(s) - hbeag , hepatitis b virus , virology , genotype , medicine , virus , biology , hbsag , gene , genetics
Abstract There are two subtypes of hepatitis B virus genotype A (HBV/A) and they are provisionally designated Aa (“a” standing for Africa/Asia) and Ae (“e” for Europe). In a case‐control study, 78 HBV/Aa, 78HBV/Ae, and 78HBV/D carriers from several countries were compared. The prevalence of HBe antigen (HBeAg) in serum was significantly lower in carriers of HBV/Aa than in carriers of HBV/Ae (31% vs. 49%; P = .033), with a difference more obvious in the carriers aged 30 years or younger (34% vs. 67%; P = .029). HBV DNA levels in the carriers of HBV/Aa (median, 3.46 log copies/mL; 95% CI, 2.93–3.95) were significantly lower than those of carriers of HBV/Ae (6.09 log copies/mL; 95% CI, 4.24–7.64) or of carriers of HBV/D (5.48 log copies/mL; 95% CI, 4.06–7.02), regardless of the HBeAg status ( P < .001). The most specific and frequent substitutions in 54 HBV/Aa isolates were double substitutions for T1809 (100%) and T1812 (96%) immediately upstream of the precore initiation codon, which would interfere with the translation of HBeAg in HBV/Aa infections. They were not detected in 57 HBV/Ae or 61 HBV/D isolates examined. The double mutation in the core promoter (T1762/A1764) was more frequent in both HBV/Aa (50%) and HBV/Ae (44%) than in HBV/D isolates (25%; P < .01), whereas the precore mutation (A1896) occurred in HBV/D isolates only (48%; P < .0001). In conclusion, the clearance of HBeAg from serum may occur by different mechanisms in HBV/Aa, HBV/Ae, and HBV/D infections, which may influence clinical manifestations in the Western countries where both genotypes A and D are prevalent. (H EPATOLOGY 2004;40:747–755.)