Table 3.
Analysis of the selection pressure of Liaoning EA H1N1 SIVs.
| Gene Segment | Positive Selection Sites of 2020 EA H1N1 SIVs | Selection Pressure (dN/dS) | ||
|---|---|---|---|---|
| 2020 a | 2014–2016 | 2006–2013 | ||
| HA b | 60, 219, 361 | 0.193 | 0.160 | 0.215 |
| NA c | - | 0.209 | 0.164 | 0.190 |
| PB2 | 391, 661 | 0.125 | - | - |
| PB1 | 14, 364, 607, 673, 683 | 0.135 | - | - |
| PA | 436, 532 | 0.163 | - | - |
| NP | 113 | 0.121 | - | - |
| M1 | - | 0.243 | - | - |
| M2 | - | 0.491 | - | - |
| NS1 | 4, 51 | 0.539 | - | - |
| NS2 | - | 0.253 | - | - |
a Selection pressure and positive selection site assessments of the 2020 EA H1N1 SIVs internal genes (PB2, PB1, PA, NP, M1, M2, NS1, NS2), not including DL1007. b Selection pressure of 11 HA genes from P1, 22 HA genes from P2, and 24 HA genes from P3. The H3 numbering system was used. c Selection pressure of 11 NA genes from P1, 18 NA genes (except 4 N2 NA) from P2, and 24 NA genes from P3.