A novel method based on ligase detection reaction for low abundant YIDD mutants detection in hepatitis B virus

A novel method based on ligase detection reaction (LDR) coupled with polymerase chain reaction (PCR) was used in this study to detect low abundant YIDD mutants in hepatitis B virus (HBV), which was able to detect 102 mutants from 108 wild type copies in plasmids and 103 from 107 in clinical serum samples. Direct sequencing and microarray hybridization were selected for sensitivity comparison together with this assay. By direct sequencing, 6 of 50 clinical specimens infected with HBV were found to be YIDD and the others to be YMDD, while by microarray hybridization, 28 specimens were detected to contain both YMDD and YIDD, and the others contained YMDD only, and with this assay, 31 specimens containing both YMDD and YIDD were detected with the others containing YMDD only, which indicated that the assay was relatively more sensitive.