FREQUENCY OF HEPATITIS-B VIRUS E-MINUS MUTANTS VARIES AMONG PATIENTS FROM DIFFERENT AREAS OF CHINA

Four hundred forty-six serum samples from HBsAg-positive chronic hepat itis B patients were collected from five areas in China (eastern coast al city, Shanghai; southwestern inland city, Chengdu; mid-inland city, Wuhan; southern island city, Haikou; and northeastern city, Changchun ). Precore stop codon variants (e-minus mutants) were screened using a rapid method of polymerase chain reaction (PCR) amplification of a pr ecore and partial core gene fragment (nucleotides 1785-2172), followed by dot-blot hybridization with specific oligonucleotide probes (M0, a nd M1 + M2). The sequence of the M0 probe covered the distal precore r egion of wild-type virus (nucleotides 1887-1908), and the sequences of the M1 and M2 probes were from sequences mutated at nt. 1898, (TGG--> TAG) with or without additional change at nt. 1901. A significantly lo wer incidence of the precore stop codon was found in anti-HBe-positive serum samples from Haikou (17.6%), whereas in other areas the percent ages of this mutation in anti-HBe positive sera ranged from 47.4% to 7 8.9%. In HBeAg-positive samples, the rate of e-minus mutant in coexist ence with wild-type virus was low in specimens from Haikou (9.5%) and Changchun (2.9%) compared to other areas in China. In contrast, coexis tence of mutant and wild-type virus was frequently detected in samples from Wuhan (50.0%). (C) 1997 Wiley-Liss, Inc.