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. 2017 Dec 14;92(1):e01580-17. doi: 10.1128/JVI.01580-17

TABLE 5.

NA sequence variations of the NAI resistance-associated substitutions identified in human and avian influenza viruses of N1 to N9 NA subtypes

NA residuea WT amino acid (subtype) Amino acid substitution NA subtype Polymorphism(s) in database (frequency [%])b
Avian No. of sequences Human No. of sequences
147 N/G (N5/N8) I/V N1 G (99.76), R (0.24) 2,110 G (99.83), Q (0.11), R (0.06) 8,065
N4, N5, N8 G (86.37), N (13.63)c 3,258 G (100) 4
N2 G (98.78), D (0.65), S (0.58) 2,776 N (73.57), D (25.83), G (0.57), Y (0.02) 8,809
N3, N6, N7, N9 G (99.94), R (0.03), T (0.01), Q (0.01) 6,733 G (99.12), Q (0.88) 113
246 A (N6) F/V N1 S (99.76), N (0.19), G (0.05) 2,111 S (99.38), N (0.57), R (0.05) 8,061
N4, N5, N8 A (89.1), S (10.81)d, T (0.09) 3,276 A (100) 4
N2 A (99.96), S (0.04) 2,775 A (99.95), T (0.03), G (0.01) 8,808
N3, N6, N7, N9 A (99.91), T (0.03), V (0.01), S (0.01), P (0.01), G (0.01) 6,719 A (100) 125
427 I (N4) L N1 I (98.72), V (1.23), T (0.05) 2,108 I (85.11), V (14.87), M (0.01) 8,061
N4, N5, N8 I (99.97), V (0.03) 3,277 I (100) 4
N2 I (99.39), V (0.4), T (0.22) 2,771 I (99.93), V (0.05), M (0.01), T (0.01) 8,805
N3, N6, N7, N9 I (97.4), T (2.51), M (0.07), V (0.01) 6,692 I (100) 113
274 H Y N1 H (99.95), Y (0.047) 2,112 H (94.31), Y (5.672), N (0.012) 8,056
N4, N5, N8 H (99.96), R (0.016), Q (0.016) 6,176 H (100) 4
N2 H (100) 2,775 H (100) 8,808
N3, N6, N7, N9 H (99.97), N (0.014), R (0.014) 6,729 H (100) 125
a

Position numbers of amino acid substitutions are based on N2 numbering.

b

Data were obtained from the Influenza Research Database.

c

N is 100% in the N5 subtype (350/350).

d

S is 99.55% in the N4 subtype (225/226).