Figure 4: Genome comparison of the nucleotide sequences for the authentic HA gene from the duck-Fukushima strain (light green) and the synthetic HA gene (orange). The codon usage of the H5HA gene was optimized for the silkworms B mori. Amino acid sequence connecting the HA1 and HA2 molecules was changed from RERRRKRG to RDTRR to reduce virulency of Fukushima genome.