TABLE 5.
Occurrence of mutations observed following experimental passages in naturally occurring IBDV genomes.
| IBDV segment | Viral protein | aasubstitutiona | Virus stock | number ofsamples where the substitution was found/total | Other IBDVstrains with similar residuesb |
| A | VP5 | Ser7Gly | rvv-p12 | 1/3 | Faragher 52/70 (cv, HG974565.1); USC2003 (vv, KU183665.1); USC2010 (vv, KU183667.1) |
| VP5 | His63Tyr | rCu-1-p12/DF-1/7DMA | 1/3 | 23/82 (serotype II, Z21971.1) | |
| VP5 | Ile74Phe | rCu-1-p12/B | 1/3 | Phenylalanine conserved in vvIBDV strains | |
| VP5 | Thr131Ala | rCu-1-p12/DF-1 | 1/3 | GX-NNZ-11 (vv, JX134483.1) | |
| VP5 | Arg133Trp | rCu-1-p12/B/7DMA | 1/3 | Tryptophane conserved in vvIBDV strains | |
| VP2 | *Pro222Leu | rCu-1-p12/B | 1/3 | 160019 (reassortant isolate, KY610529.1) | |
| VP2 | Gln249Arg | rCu-1-p12/DF-1 | 1/3 | IC-IBDV-Br (KC603937.1); P2 (cv, X84034.1); Gt (cv, DQ403248.1) | |
| VP2 | *Ala270Glu | rvv-p12 | 3/3 | UPM94/273 (vv, AF527039.1); OH (serotype II, U30818.1) | |
| VP2 | *Ala270Thr | rvv-p12/7DMA | 3/3 | Threonine highly conserved in cvIBDV strains | |
| VP4 | *Cys680Tyr | rCu-1-p12/B, rCu-1-p12/B/7DMA, rCu-1-p12/DF-1, rCu-1-p12/DF-1/7DMA | 8/12 | Tyrosine highly conserved in vvIBDV strains | |
| VP4 | Cys680Arg | rCu-1-p12/B | 1/3 | 23/82 (serotype II, Z21971.1) | |
| VP4 | *Ala713Thr | rCu-1-p5/ch, rCu-1-p12/B, rCu-1-p12/B/7DMA | 4/7 | Threonine presents in all sequences analyzed | |
| VP4 | Tyr741His | rvv-p12, rvv-p12/7DMA | 4/6 | 100056 (reassortant isolate, KU234528.1) | |
| B | VP1 | *Thr329Ala | rvv-p12/7DMA, rCu-1-p12/B/7DMA, rCu-1-p12/DF-1/7DMA | 9/9 | IBD13HeB01 (reassortant isolate, AKD94180.1) |
| VP1 | Val865Ala | rCu-1-p12/B/7DMA, rCu-1-p12/DF-1/7DMA | 2/6 | HBDY-1 (KX592159.1); OH (serotype II, U30819.1) |
aAmino acid (aa) substitution indicated using numbering of VP5 ORF, polyprotein or VP1 ORF. bThe IBDV classification belonging to serotype I [classical virulent (cv); very virulent (vv)], serotype II or defined as a reassortant isolate was indicated when it was possible. In brackets, Genbank accession numbers. *Dominant mutations.