The putative secondary 5′UTR RNA structure of BEV-AN12 is shown in Fig. 1. Zell et al. reported that the 5′UTR of BEVs form additional cloverleaf structures and small stem loops between the 5′-cloverleaf structure and IRES, which clearly distinguish BEVs from other EVs . Similarly, our analysis revealed that all Japanese BEVs had BEV-specific structures (domains I* and I**). Domains II, III, IV, V and VI, which are the main domains of type 1 IRES directing cap-independent translation , were also observed in all Japanese BEVs.Fig. 1Secondary RNA structure of 5′UTR of BEV-AN12. Putative secondary RNA structure of 5′UTR of BEV-AN12 was predicted by Mfold. Domains I, I*, I**, II, III, IV, V and VI domain were predicted. Domains I* and I** conserved among BEVs are shown with a bold line. Yn-Xm-AUG motif conserved in domain VI is indicated by a bold line. Kozak consensus sequences with start codon are also indicated by a bold line