Table 1.
Mutations in genetic groups 1–8 of A(H1N1)pdm09 with the specified reference strain belonging to the genetic group. The mutations in HA1 and HA2 are outlined, with mutations in HA2 highlighted in blue font.
| Group | Mutations | Reference Strain |
|---|---|---|
| 1 | A/California/07/2009 * | |
| 2 | N31D, S162N (+CHO), A186T in HA1, E47K and S124N in HA2 | - |
| 3 | A134T and S183P in HA1 | A/Hong Kong/3934/2011 |
| 4 | N125D in HA1 and E47K in HA2 | A/Christchurch/16/2010 |
| 5 | D97N, R205K, I216V, V249L in HA1 and E47K in HA2 | A/Astrakhan/1/2011 |
| 6 | D97N, S185T in HA1, E47K and S124N in HA2 | A/St. Petersburg/27/2011 |
| 6A | H138R, V249L in HA1 | A/St. Petersburg/27/2011 |
| 6B | D97N, S185T, S203T K163Q, A256T and K283E in HA1, and E47K, S124N, E172K in HA2 | A/Michigan/45/2015* |
| 6B.1 | S84N, S162N (+CHO) and I216T in HA1 | A/Michigan/45/2015* |
| 6B.2 | V152T and V173I in HA1 and E164G and D174E in HA2 | - |
| 6C | V234I in HA1; some viruses also have substitutions V30A and A186T in HA1; | - |
| 7 | S143G, S185T, A197T in HA1, E47K and S124N in HA2 | A/St. Petersburg/100/2011 |
| 8 | A186T, V272A in HA1, E47K, N146D, T147K and V193A in HA2 | - |
Note: * Vaccine strains.