Genotyping and mutational analysis of occult hepatitis B virus infection in blood donors of Shaoxing

Abstract

To assess the molecular biological characteristics of occult hepatitis B virus (HBV) infected blood donors in Shaoxing. 8692 blood donors were screened using ELISA. The occult HBV infection was determined by DNA analysis among the HBsAg negative subjects. DNA sequencing and mutational analysis were further performed in the HBV DNA positive samples. The overall situation of occult HBV infection was hereby evaluated and the possible underlying mechanisms discussed. Among the 8644 HBsAg negative subjects out of 8692 blood donors, 8 were HBV DNA positive. The occult HBV infection rate was 0.92 per thousand (8/8692). Among the 8 samples, 6 were genotype C (75%) and 2 genotype B (25%). In addition, a specific mutation in "a" epitope was observed in 7 OBI virus strains by amino acid analysis. There were occult HBV infected among blood donors in Shaoxing, which is probably associated with the gene mutation of HBV virus.