The analysis of the full-length sequence of HEV genotype IV

Objective To analyze the full-length sequence of HEV genotype Ⅳ and compare it with that of HEV genotype Ⅰ, Ⅱ and Ⅲ. Methods The fragments of HEV genotype Ⅳ were amplified with RT-PCR and the 5′ and 3′ ends were amplified with RACE. The PCR products were cloned and sequenced. Results The full-length sequence of HEV-T1 showed homogeneous of 74.8%-75.5%, 74.5% and 75.3%-76.3% with HEV genotype Ⅰ, Ⅱ and Ⅲ respectively. ORF1 protein of HEV-T1 has 85.0%-86.7%, 85.0% and 88.5%-88.7% identical to HEV genotype Ⅰ, Ⅱ and Ⅲ respectively with amino acid composition. ORF2 protein of HEV-T1 is homogenous by 91.6%-92.4%, 90.1% and 91.9%-93.0% to HEV Ⅰ, Ⅱ and Ⅲ respectively and ORF3 has 75.9%-77.8%, 75.0% and 79.6%-83.8% identical to HEV Ⅰ, Ⅱ and Ⅲ respectively. Conclusion This study provides the new molecular basis for the development of HEV diagnostic kit and vaccine.