Gene Nucleotide Amino acid position Amino acid substitutions in the internal genes of the virus Lwt1 L17-MDV LAIV candidate (# of passage) VN/H5N2 (0) VN/H5N2 (5) t/T/H5N2 ( 0) t/T/H5N2 (5) VN/H5N1- RG (0) VN/H5N1-RG (5) PB2 1459 478 Val Leu Leu Leu Leu Leu Leu Leu PB1 819 265 Lys Asn Asn Asn Asn Asn Asn Asn 1795 591 Val Ile Ile Ile Ile Ile Ile Ile PA 107 28 Leu Pro Pro Pro Pro Pro Pro Pro 1045 341 Val Leu Leu Leu Leu Leu Leu Leu NP NP gene of Len17-MDV(H2N2) does not contain coding mutations M1 68 15 Ile Val Val Val Val Val Val Val 457 144 Phe Leu Leu Leu Leu Leu Leu Leu NS2 798 100 Met Ile Ile Ile Ile Ile Ile Ile

Table 3: Genetic stability of coding mutations in the internal genes of H5-LAIV candidates after the 5-fold passages in the developing chick embryos at 32ºC.